Commit Graph

462 Commits

Author SHA1 Message Date
Yisheng Xie 78c72746f5 vmalloc: show lazy-purged vma info in vmallocinfo
When ioremap a 67112960 bytes vm_area with the vmallocinfo:
 [..]
 0xec79b000-0xec7fa000  389120 ftl_add_mtd+0x4d0/0x754 pages=94 vmalloc
 0xec800000-0xecbe1000 4067328 kbox_proc_mem_write+0x104/0x1c4 phys=8b520000 ioremap

we get the result:
 0xf1000000-0xf5001000 67112960 devm_ioremap+0x38/0x7c phys=40000000 ioremap

For the align for ioremap must be less than '1 << IOREMAP_MAX_ORDER':

	if (flags & VM_IOREMAP)
		align = 1ul << clamp_t(int, get_count_order_long(size),
			PAGE_SHIFT, IOREMAP_MAX_ORDER);

So it makes idiot like me a litte puzzled why this was a jump the
vm_area from 0xec800000-0xecbe1000 to 0xf1000000-0xf5001000, and leaving
0xed000000-0xf1000000 as a big hole.

This patch is to show all of vm_area, including vmas which are freeing
but still in the vmap_area_list, to make it more clear about why we will
get 0xf1000000-0xf5001000 in the above case.  And we will get a
vmallocinfo like:

 [..]
 0xec79b000-0xec7fa000  389120 ftl_add_mtd+0x4d0/0x754 pages=94 vmalloc
 0xec800000-0xecbe1000 4067328 kbox_proc_mem_write+0x104/0x1c4 phys=8b520000 ioremap
 [..]
 0xece7c000-0xece7e000    8192 unpurged vm_area
 0xece7e000-0xece83000   20480 vm_map_ram
 0xf0099000-0xf00aa000   69632 vm_map_ram

after this patch.

Link: http://lkml.kernel.org/r/1496649682-20710-1-git-send-email-xieyisheng1@huawei.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: zijun_hu <zijun_hu@htc.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-10 16:32:31 -07:00
Catalin Marinas 94f4a1618b mm: kmemleak: treat vm_struct as alternative reference to vmalloc'ed objects
Kmemleak requires that vmalloc'ed objects have a minimum reference count
of 2: one in the corresponding vm_struct object and the other owned by
the vmalloc() caller.  There are cases, however, where the original
vmalloc() returned pointer is lost and, instead, a pointer to vm_struct
is stored (see free_thread_stack()).  Kmemleak currently reports such
objects as leaks.

This patch adds support for treating any surplus references to an object
as additional references to a specified object.  It introduces the
kmemleak_vmalloc() API function which takes a vm_struct pointer and sets
its surplus reference passing to the actual vmalloc() returned pointer.
The __vmalloc_node_range() calling site has been modified accordingly.

Link: http://lkml.kernel.org/r/1495726937-23557-4-git-send-email-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: "Luis R. Rodriguez" <mcgrof@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:34 -07:00
Ard Biesheuvel 029c54b095 mm/vmalloc.c: huge-vmap: fail gracefully on unexpected huge vmap mappings
Existing code that uses vmalloc_to_page() may assume that any address
for which is_vmalloc_addr() returns true may be passed into
vmalloc_to_page() to retrieve the associated struct page.

This is not un unreasonable assumption to make, but on architectures
that have CONFIG_HAVE_ARCH_HUGE_VMAP=y, it no longer holds, and we need
to ensure that vmalloc_to_page() does not go off into the weeds trying
to dereference huge PUDs or PMDs as table entries.

Given that vmalloc() and vmap() themselves never create huge mappings or
deal with compound pages at all, there is no correct answer in this
case, so return NULL instead, and issue a warning.

When reading /proc/kcore on arm64, you will hit an oops as soon as you
hit the huge mappings used for the various segments that make up the
mapping of vmlinux.  With this patch applied, you will no longer hit the
oops, but the kcore contents willl be incorrect (these regions will be
zeroed out)

We are fixing this for kcore specifically, so it avoids vread() for
those regions.  At least one other problematic user exists, i.e.,
/dev/kmem, but that is currently broken on arm64 for other reasons.

Link: http://lkml.kernel.org/r/20170609082226.26152-1-ard.biesheuvel@linaro.org
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Laura Abbott <labbott@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: zhong jiang <zhongjiang@huawei.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-06-23 16:15:55 -07:00
Michal Hocko 8594a21cf7 mm, vmalloc: fix vmalloc users tracking properly
Commit 1f5307b1e0 ("mm, vmalloc: properly track vmalloc users") has
pulled asm/pgtable.h include dependency to linux/vmalloc.h and that
turned out to be a bad idea for some architectures.  E.g.  m68k fails
with

   In file included from arch/m68k/include/asm/pgtable_mm.h:145:0,
                    from arch/m68k/include/asm/pgtable.h:4,
                    from include/linux/vmalloc.h:9,
                    from arch/m68k/kernel/module.c:9:
   arch/m68k/include/asm/mcf_pgtable.h: In function 'nocache_page':
>> arch/m68k/include/asm/mcf_pgtable.h:339:43: error: 'init_mm' undeclared (first use in this function)
    #define pgd_offset_k(address) pgd_offset(&init_mm, address)

as spotted by kernel build bot. nios2 fails for other reason

  In file included from include/asm-generic/io.h:767:0,
                   from arch/nios2/include/asm/io.h:61,
                   from include/linux/io.h:25,
                   from arch/nios2/include/asm/pgtable.h:18,
                   from include/linux/mm.h:70,
                   from include/linux/pid_namespace.h:6,
                   from include/linux/ptrace.h:9,
                   from arch/nios2/include/uapi/asm/elf.h:23,
                   from arch/nios2/include/asm/elf.h:22,
                   from include/linux/elf.h:4,
                   from include/linux/module.h:15,
                   from init/main.c:16:
  include/linux/vmalloc.h: In function '__vmalloc_node_flags':
  include/linux/vmalloc.h:99:40: error: 'PAGE_KERNEL' undeclared (first use in this function); did you mean 'GFP_KERNEL'?

which is due to the newly added #include <asm/pgtable.h>, which on nios2
includes <linux/io.h> and thus <asm/io.h> and <asm-generic/io.h> which
again includes <linux/vmalloc.h>.

Tweaking that around just turns out a bigger headache than necessary.
This patch reverts 1f5307b1e0 and reimplements the original fix in a
different way.  __vmalloc_node_flags can stay static inline which will
cover vmalloc* functions.  We only have one external user
(kvmalloc_node) and we can export __vmalloc_node_flags_caller and
provide the caller directly.  This is much simpler and it doesn't really
need any games with header files.

[akpm@linux-foundation.org: coding-style fixes]
[mhocko@kernel.org: revert old comment]
  Link: http://lkml.kernel.org/r/20170509211054.GB16325@dhcp22.suse.cz
Fixes: 1f5307b1e0 ("mm, vmalloc: properly track vmalloc users")
Link: http://lkml.kernel.org/r/20170509153702.GR6481@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-12 15:57:15 -07:00
Linus Torvalds e47b40a235 arm64 2nd set of updates for 4.12:
- Silence module allocation failures when CONFIG_ARM*_MODULE_PLTS is
   enabled. This requires a check for __GFP_NOWARN in alloc_vmap_area()
 
 - Improve/sanitise user tagged pointers handling in the kernel
 
 - Inline asm fixes/cleanups
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull more arm64 updates from Catalin Marinas:

 - Silence module allocation failures when CONFIG_ARM*_MODULE_PLTS is
   enabled. This requires a check for __GFP_NOWARN in alloc_vmap_area()

 - Improve/sanitise user tagged pointers handling in the kernel

 - Inline asm fixes/cleanups

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Silence first allocation with CONFIG_ARM64_MODULE_PLTS=y
  ARM: Silence first allocation with CONFIG_ARM_MODULE_PLTS=y
  mm: Silence vmap() allocation failures based on caller gfp_flags
  arm64: uaccess: suppress spurious clang warning
  arm64: atomic_lse: match asm register sizes
  arm64: armv8_deprecated: ensure extension of addr
  arm64: uaccess: ensure extension of access_ok() addr
  arm64: ensure extension of smp_store_release value
  arm64: xchg: hazard against entire exchange variable
  arm64: documentation: document tagged pointer stack constraints
  arm64: entry: improve data abort handling of tagged pointers
  arm64: hw_breakpoint: fix watchpoint matching for tagged pointers
  arm64: traps: fix userspace cache maintenance emulation on a tagged pointer
2017-05-11 11:27:54 -07:00
Florian Fainelli 03497d761c mm: Silence vmap() allocation failures based on caller gfp_flags
If the caller has set __GFP_NOWARN don't print the following message:
vmap allocation for size 15736832 failed: use vmalloc=<size> to increase
size.

This can happen with the ARM/Linux or ARM64/Linux module loader built
with CONFIG_ARM{,64}_MODULE_PLTS=y which does a first attempt at loading
a large module from module space, then falls back to vmalloc space.

Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-05-11 14:41:26 +01:00
Michal Hocko 19809c2da2 mm, vmalloc: use __GFP_HIGHMEM implicitly
__vmalloc* allows users to provide gfp flags for the underlying
allocation.  This API is quite popular

  $ git grep "=[[:space:]]__vmalloc\|return[[:space:]]*__vmalloc" | wc -l
  77

The only problem is that many people are not aware that they really want
to give __GFP_HIGHMEM along with other flags because there is really no
reason to consume precious lowmemory on CONFIG_HIGHMEM systems for pages
which are mapped to the kernel vmalloc space.  About half of users don't
use this flag, though.  This signals that we make the API unnecessarily
too complex.

This patch simply uses __GFP_HIGHMEM implicitly when allocating pages to
be mapped to the vmalloc space.  Current users which add __GFP_HIGHMEM
are simplified and drop the flag.

Link: http://lkml.kernel.org/r/20170307141020.29107-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Cristopher Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:13 -07:00
Michal Hocko 1f5307b1e0 mm, vmalloc: properly track vmalloc users
__vmalloc_node_flags used to be static inline but this has changed by
"mm: introduce kv[mz]alloc helpers" because kvmalloc_node needs to use
it as well and the code is outside of the vmalloc proper.  I haven't
realized that changing this will lead to a subtle bug though.  The
function is responsible to track the caller as well.  This caller is
then printed by /proc/vmallocinfo.  If __vmalloc_node_flags is not
inline then we would get only direct users of __vmalloc_node_flags as
callers (e.g.  v[mz]alloc) which reduces usefulness of this debugging
feature considerably.  It simply doesn't help to see that the given
range belongs to vmalloc as a caller:

  0xffffc90002c79000-0xffffc90002c7d000   16384 vmalloc+0x16/0x18 pages=3 vmalloc N0=3
  0xffffc90002c81000-0xffffc90002c85000   16384 vmalloc+0x16/0x18 pages=3 vmalloc N1=3
  0xffffc90002c8d000-0xffffc90002c91000   16384 vmalloc+0x16/0x18 pages=3 vmalloc N1=3
  0xffffc90002c95000-0xffffc90002c99000   16384 vmalloc+0x16/0x18 pages=3 vmalloc N1=3

We really want to catch the _caller_ of the vmalloc function.  Fix this
issue by making __vmalloc_node_flags static inline again.

Link: http://lkml.kernel.org/r/20170502134657.12381-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:12 -07:00
Michal Hocko a7c3e901a4 mm: introduce kv[mz]alloc helpers
Patch series "kvmalloc", v5.

There are many open coded kmalloc with vmalloc fallback instances in the
tree.  Most of them are not careful enough or simply do not care about
the underlying semantic of the kmalloc/page allocator which means that
a) some vmalloc fallbacks are basically unreachable because the kmalloc
part will keep retrying until it succeeds b) the page allocator can
invoke a really disruptive steps like the OOM killer to move forward
which doesn't sound appropriate when we consider that the vmalloc
fallback is available.

As it can be seen implementing kvmalloc requires quite an intimate
knowledge if the page allocator and the memory reclaim internals which
strongly suggests that a helper should be implemented in the memory
subsystem proper.

Most callers, I could find, have been converted to use the helper
instead.  This is patch 6.  There are some more relying on __GFP_REPEAT
in the networking stack which I have converted as well and Eric Dumazet
was not opposed [2] to convert them as well.

[1] http://lkml.kernel.org/r/20170130094940.13546-1-mhocko@kernel.org
[2] http://lkml.kernel.org/r/1485273626.16328.301.camel@edumazet-glaptop3.roam.corp.google.com

This patch (of 9):

Using kmalloc with the vmalloc fallback for larger allocations is a
common pattern in the kernel code.  Yet we do not have any common helper
for that and so users have invented their own helpers.  Some of them are
really creative when doing so.  Let's just add kv[mz]alloc and make sure
it is implemented properly.  This implementation makes sure to not make
a large memory pressure for > PAGE_SZE requests (__GFP_NORETRY) and also
to not warn about allocation failures.  This also rules out the OOM
killer as the vmalloc is a more approapriate fallback than a disruptive
user visible action.

This patch also changes some existing users and removes helpers which
are specific for them.  In some cases this is not possible (e.g.
ext4_kvmalloc, libcfs_kvzalloc) because those seems to be broken and
require GFP_NO{FS,IO} context which is not vmalloc compatible in general
(note that the page table allocation is GFP_KERNEL).  Those need to be
fixed separately.

While we are at it, document that __vmalloc{_node} about unsupported gfp
mask because there seems to be a lot of confusion out there.
kvmalloc_node will warn about GFP_KERNEL incompatible (which are not
superset) flags to catch new abusers.  Existing ones would have to die
slowly.

[sfr@canb.auug.org.au: f2fs fixup]
  Link: http://lkml.kernel.org/r/20170320163735.332e64b7@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170306103032.2540-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>	[ext4 part]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:12 -07:00
Linus Torvalds c58d4055c0 A reasonably busy cycle for documentation this time around. There is a new
guide for user-space API documents, rather sparsely populated at the
 moment, but it's a start.  Markus improved the infrastructure for
 converting diagrams.  Mauro has converted much of the USB documentation
 over to RST.  Plus the usual set of fixes, improvements, and tweaks.
 
 There's a bit more than the usual amount of reaching out of Documentation/
 to fix comments elsewhere in the tree; I have acks for those where I could
 get them.
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Merge tag 'docs-4.12' of git://git.lwn.net/linux

Pull documentation update from Jonathan Corbet:
 "A reasonably busy cycle for documentation this time around. There is a
  new guide for user-space API documents, rather sparsely populated at
  the moment, but it's a start. Markus improved the infrastructure for
  converting diagrams. Mauro has converted much of the USB documentation
  over to RST. Plus the usual set of fixes, improvements, and tweaks.

  There's a bit more than the usual amount of reaching out of
  Documentation/ to fix comments elsewhere in the tree; I have acks for
  those where I could get them"

* tag 'docs-4.12' of git://git.lwn.net/linux: (74 commits)
  docs: Fix a couple typos
  docs: Fix a spelling error in vfio-mediated-device.txt
  docs: Fix a spelling error in ioctl-number.txt
  MAINTAINERS: update file entry for HSI subsystem
  Documentation: allow installing man pages to a user defined directory
  Doc/PM: Sync with intel_powerclamp code behavior
  zr364xx.rst: usb/devices is now at /sys/kernel/debug/
  usb.rst: move documentation from proc_usb_info.txt to USB ReST book
  convert philips.txt to ReST and add to media docs
  docs-rst: usb: update old usbfs-related documentation
  arm: Documentation: update a path name
  docs: process/4.Coding.rst: Fix a couple of document refs
  docs-rst: fix usb cross-references
  usb: gadget.h: be consistent at kernel doc macros
  usb: composite.h: fix two warnings when building docs
  usb: get rid of some ReST doc build errors
  usb.rst: get rid of some Sphinx errors
  usb/URB.txt: convert to ReST and update it
  usb/persist.txt: convert to ReST and add to driver-api book
  usb/hotplug.txt: convert to ReST and add to driver-api book
  ...
2017-05-02 10:21:17 -07:00
mchehab@s-opensource.com 0e056eb553 kernel-api.rst: fix a series of errors when parsing C files
./lib/string.c:134: WARNING: Inline emphasis start-string without end-string.
./mm/filemap.c:522: WARNING: Inline interpreted text or phrase reference start-string without end-string.
./mm/filemap.c:1283: ERROR: Unexpected indentation.
./mm/filemap.c:3003: WARNING: Inline interpreted text or phrase reference start-string without end-string.
./mm/vmalloc.c:1544: WARNING: Inline emphasis start-string without end-string.
./mm/page_alloc.c:4245: ERROR: Unexpected indentation.
./ipc/util.c:676: ERROR: Unexpected indentation.
./drivers/pci/irq.c:35: WARNING: Block quote ends without a blank line; unexpected unindent.
./security/security.c:109: ERROR: Unexpected indentation.
./security/security.c:110: WARNING: Definition list ends without a blank line; unexpected unindent.
./block/genhd.c:275: WARNING: Inline strong start-string without end-string.
./block/genhd.c:283: WARNING: Inline strong start-string without end-string.
./include/linux/clk.h:134: WARNING: Inline emphasis start-string without end-string.
./include/linux/clk.h:134: WARNING: Inline emphasis start-string without end-string.
./ipc/util.c:477: ERROR: Unknown target name: "s".

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-04-02 14:31:49 -06:00
Dmitry Vyukov 171012f561 mm: don't warn when vmalloc() fails due to a fatal signal
When vmalloc() fails it prints a very lengthy message with all the
details about memory consumption assuming that it happened due to OOM.

However, vmalloc() can also fail due to fatal signal pending.  In such
case the message is quite confusing because it suggests that it is OOM
but the numbers suggest otherwise.  The messages can also pollute
console considerably.

Don't warn when vmalloc() fails due to fatal signal pending.

Link: http://lkml.kernel.org/r/20170313114425.72724-1-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-16 16:56:18 -07:00
Kirill A. Shutemov c2febafc67 mm: convert generic code to 5-level paging
Convert all non-architecture-specific code to 5-level paging.

It's mostly mechanical adding handling one more page table level in
places where we deal with pud_t.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-03-09 11:48:47 -08:00
Ingo Molnar c3edc4010e sched/headers: Move task_struct::signal and task_struct::sighand types and accessors into <linux/sched/signal.h>
task_struct::signal and task_struct::sighand are pointers, which would normally make it
straightforward to not define those types in sched.h.

That is not so, because the types are accompanied by a myriad of APIs (macros and inline
functions) that dereference them.

Split the types and the APIs out of sched.h and move them into a new header, <linux/sched/signal.h>.

With this change sched.h does not know about 'struct signal' and 'struct sighand' anymore,
trying to put accessors into sched.h as a test fails the following way:

  ./include/linux/sched.h: In function ‘test_signal_types’:
  ./include/linux/sched.h:2461:18: error: dereferencing pointer to incomplete type ‘struct signal_struct’
                    ^

This reduces the size and complexity of sched.h significantly.

Update all headers and .c code that relied on getting the signal handling
functionality from <linux/sched.h> to include <linux/sched/signal.h>.

The list of affected files in the preparatory patch was partly generated by
grepping for the APIs, and partly by doing coverage build testing, both
all[yes|mod|def|no]config builds on 64-bit and 32-bit x86, and an array of
cross-architecture builds.

Nevertheless some (trivial) build breakage is still expected related to rare
Kconfig combinations and in-flight patches to various kernel code, but most
of it should be handled by this patch.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-03 01:43:37 +01:00
Miles Chen 199eaa05ad mm: cleanups for printing phys_addr_t and dma_addr_t
cleanup rest of dma_addr_t and phys_addr_t type casting in mm
use %pad for dma_addr_t
use %pa for phys_addr_t

Link: http://lkml.kernel.org/r/1486618489-13912-1-git-send-email-miles.chen@mediatek.com
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
Michal Hocko 5d17a73a2e vmalloc: back off when the current task is killed
__vmalloc_area_node() allocates pages to cover the requested vmalloc
size.  This can be a lot of memory.  If the current task is killed by
the OOM killer, and thus has an unlimited access to memory reserves, it
can consume all the memory theoretically.  Fix this by checking for
fatal_signal_pending and back off early.

Link: http://lkml.kernel.org/r/20170201092706.9966-4-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Michal Hocko a8e99259e7 mm, page_alloc: warn_alloc print nodemask
warn_alloc is currently used for to report an allocation failure or an
allocation stall.  We print some details of the allocation request like
the gfp mask and the request order.  We do not print the allocation
nodemask which is important when debugging the reason for the allocation
failure as well.  We alreaddy print the nodemask in the OOM report.

Add nodemask to warn_alloc and print it in warn_alloc as well.

Link: http://lkml.kernel.org/r/20170117091543.25850-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-22 16:41:30 -08:00
Geliang Tang 4583e77310 mm/vmalloc.c: use rb_entry_safe
Use rb_entry_safe() instead of open-coding it.

Link: http://lkml.kernel.org/r/81bb9820e5b9e4a1c596b3e76f88abf8c4a76cb0.1482221947.git.geliangtang@gmail.com
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-22 16:41:27 -08:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Joel Fernandes 763b218ddf mm: add preempt points into __purge_vmap_area_lazy()
Use cond_resched_lock to avoid holding the vmap_area_lock for a
potentially long time and thus creating bad latencies for various
workloads.

[hch: split from a larger patch by Joel, wrote the crappy changelog]
Link: http://lkml.kernel.org/r/1479474236-4139-11-git-send-email-hch@lst.de
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Dias <joaodias@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
Christoph Hellwig f9e0997767 mm: turn vmap_purge_lock into a mutex
The purge_lock spinlock causes high latencies with non RT kernel.  This
has been reported multiple times on lkml [1] [2] and affects
applications like audio.

This patch replaces it with a mutex to allow preemption while holding
the lock.

Thanks to Joel Fernandes for the detailed report and analysis as well as
an earlier attempt at fixing this issue.

[1] http://lists.openwall.net/linux-kernel/2016/03/23/29
[2] https://lkml.org/lkml/2016/10/9/59

Link: http://lkml.kernel.org/r/1479474236-4139-10-git-send-email-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Dias <joaodias@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
Christoph Hellwig 5803ed292e mm: mark all calls into the vmalloc subsystem as potentially sleeping
We will take a sleeping lock in later in this series, so this adds the
proper safeguards.

Link: http://lkml.kernel.org/r/1479474236-4139-9-git-send-email-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Dias <joaodias@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
Andrey Ryabinin bf22e37a64 mm: add vfree_atomic()
We are going to use sleeping lock for freeing vmap.  However some
vfree() users want to free memory from atomic (but not from interrupt)
context.  For this we add vfree_atomic() - deferred variation of vfree()
which can be used in any atomic context (except NMIs).

[akpm@linux-foundation.org: tweak comment grammar]
[aryabinin@virtuozzo.com: use raw_cpu_ptr() instead of this_cpu_ptr()]
  Link: http://lkml.kernel.org/r/1481553981-3856-1-git-send-email-aryabinin@virtuozzo.com
Link: http://lkml.kernel.org/r/1479474236-4139-5-git-send-email-hch@lst.de
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Jisheng Zhang <jszhang@marvell.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Dias <joaodias@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
Christoph Hellwig 0574ecd141 mm: refactor __purge_vmap_area_lazy()
Move the purge_lock synchronization to the callers, move the call to
purge_fragmented_blocks_allcpus at the beginning of the function to the
callers that need it, move the force_flush behavior to the caller that
needs it, and pass start and end by value instead of by reference.

No change in behavior.

Link: http://lkml.kernel.org/r/1479474236-4139-4-git-send-email-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Dias <joaodias@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
Christoph Hellwig 9c3acf6043 mm: remove free_unmap_vmap_area_addr()
Just inline it into the only caller.

Link: http://lkml.kernel.org/r/1479474236-4139-3-git-send-email-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Dias <joaodias@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
Christoph Hellwig c8eef01e2f mm: remove free_unmap_vmap_area_noflush()
Patch series "reduce latency in __purge_vmap_area_lazy", v2.

This patch (of 10):

Sort out the long lock hold times in __purge_vmap_area_lazy.  It is
based on a patch from Joel.

Inline free_unmap_vmap_area_noflush() it into the only caller.

Link: http://lkml.kernel.org/r/1479474236-4139-2-git-send-email-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jisheng Zhang <jszhang@marvell.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Dias <joaodias@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
zijun_hu 3f5000693f mm/vmalloc.c: simplify /proc/vmallocinfo implementation
Many seq_file helpers exist for simplifying implementation of virtual
files especially, for /proc nodes.  however, the helpers for iteration
over list_head are available but aren't adopted to implement
/proc/vmallocinfo currently.

Simplify /proc/vmallocinfo implementation by using existing seq_file
helpers.

Link: http://lkml.kernel.org/r/57FDF2E5.1000201@zoho.com
Signed-off-by: zijun_hu <zijun_hu@htc.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:07 -08:00
Michal Hocko 7877cdcc38 mm: consolidate warn_alloc_failed users
warn_alloc_failed is currently used from the page and vmalloc
allocators.  This is a good reuse of the code except that vmalloc would
appreciate a slightly different warning message.  This is already
handled by the fmt parameter except that

  "%s: page allocation failure: order:%u, mode:%#x(%pGg)"

is printed anyway.  This might be quite misleading because it might be a
vmalloc failure which leads to the warning while the page allocator is
not the culprit here.  Fix this by always using the fmt string and only
print the context that makes sense for the particular context (e.g.
order makes only very little sense for the vmalloc context).

Rename the function to not miss any user and also because a later patch
will reuse it also for !failure cases.

Link: http://lkml.kernel.org/r/20160929084407.7004-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07 18:46:29 -07:00
zijun_hu 252e5c6e2e mm/vmalloc.c: fix align value calculation error
It causes double align requirement for __get_vm_area_node() if parameter
size is power of 2 and VM_IOREMAP is set in parameter flags, for example
size=0x10000 -> fls_long(0x10000)=17 -> align=0x20000

get_count_order_long() is implemented and can be used instead of
fls_long() for fixing the bug, for example size=0x10000 ->
get_count_order_long(0x10000)=16 -> align=0x10000

[akpm@linux-foundation.org: s/get_order_long()/get_count_order_long()/]
[zijun_hu@zoho.com: fixes]
 Link: http://lkml.kernel.org/r/57AABC8B.1040409@zoho.com
[akpm@linux-foundation.org: locate get_count_order_long() next to get_count_order()]
[akpm@linux-foundation.org: move get_count_order[_long] definitions to pick up fls_long()]
[zijun_hu@htc.com: move out get_count_order[_long]() from __KERNEL__ scope]
 Link: http://lkml.kernel.org/r/57B2C4CE.80303@zoho.com
Link: http://lkml.kernel.org/r/fc045ecf-20fa-0722-b3ac-9a6140488fad@zoho.com
Signed-off-by: zijun_hu <zijun_hu@htc.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: zijun_hu <zijun_hu@htc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07 18:46:26 -07:00
Vladimir Davydov 4949148ad4 mm: charge/uncharge kmemcg from generic page allocator paths
Currently, to charge a non-slab allocation to kmemcg one has to use
alloc_kmem_pages helper with __GFP_ACCOUNT flag.  A page allocated with
this helper should finally be freed using free_kmem_pages, otherwise it
won't be uncharged.

This API suits its current users fine, but it turns out to be impossible
to use along with page reference counting, i.e.  when an allocation is
supposed to be freed with put_page, as it is the case with pipe or unix
socket buffers.

To overcome this limitation, this patch moves charging/uncharging to
generic page allocator paths, i.e.  to __alloc_pages_nodemask and
free_pages_prepare, and zaps alloc/free_kmem_pages helpers.  This way,
one can use any of the available page allocation functions to get the
allocated page charged to kmemcg - it's enough to pass __GFP_ACCOUNT,
just like in case of kmalloc and friends.  A charged page will be
automatically uncharged on free.

To make it possible, we need to mark pages charged to kmemcg somehow.
To avoid introducing a new page flag, we make use of page->_mapcount for
marking such pages.  Since pages charged to kmemcg are not supposed to
be mapped to userspace, it should work just fine.  There are other
(ab)users of page->_mapcount - buddy and balloon pages - but we don't
conflict with them.

In case kmemcg is compiled out or not used at runtime, this patch
introduces no overhead to generic page allocator paths.  If kmemcg is
used, it will be plus one gfp flags check on alloc and plus one
page->_mapcount check on free, which shouldn't hurt performance, because
the data accessed are hot.

Link: http://lkml.kernel.org/r/a9736d856f895bcb465d9f257b54efe32eda6f99.1464079538.git.vdavydov@virtuozzo.com
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Guillermo Julián Moreno 65ee03c4b9 mm: fix overflow in vm_map_ram()
When remapping pages accounting for 4G or more memory space, the
operation 'count << PAGE_SHIFT' overflows as it is performed on an
integer.  Solution: cast before doing the bitshift.

[akpm@linux-foundation.org: fix vm_unmap_ram() also]
[akpm@linux-foundation.org: fix vmap() as well, per Guillermo]
Link: http://lkml.kernel.org/r/etPan.57175fb3.7a271c6b.2bd@naudit.es
Signed-off-by: Guillermo Julián Moreno <guillermo.julian@naudit.es>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-03 15:06:22 -07:00
Linus Torvalds 1d6da87a32 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull drm updates from Dave Airlie:
 "Here's the main drm pull request for 4.7, it's been a busy one, and
  I've been a bit more distracted in real life this merge window.  Lots
  more ARM drivers, not sure if it'll ever end.  I think I've at least
  one more coming the next merge window.

  But changes are all over the place, support for AMD Polaris GPUs is in
  here, some missing GM108 support for nouveau (found in some Lenovos),
  a bunch of MST and skylake fixes.

  I've also noticed a few fixes from Arnd in my inbox, that I'll try and
  get in asap, but I didn't think they should hold this up.

  New drivers:
   - Hisilicon kirin display driver
   - Mediatek MT8173 display driver
   - ARC PGU - bitstreamer on Synopsys ARC SDP boards
   - Allwinner A13 initial RGB output driver
   - Analogix driver for DisplayPort IP found in exynos and rockchip

  DRM Core:
   - UAPI headers fixes and C++ safety
   - DRM connector reference counting
   - DisplayID mode parsing for Dell 5K monitors
   - Removal of struct_mutex from drivers
   - Connector registration cleanups
   - MST robustness fixes
   - MAINTAINERS updates
   - Lockless GEM object freeing
   - Generic fbdev deferred IO support

  panel:
   - Support for a bunch of new panels

  i915:
   - VBT refactoring
   - PLL computation cleanups
   - DSI support for BXT
   - Color manager support
   - More atomic patches
   - GEM improvements
   - GuC fw loading fixes
   - DP detection fixes
   - SKL GPU hang fixes
   - Lots of BXT fixes

  radeon/amdgpu:
   - Initial Polaris support
   - GPUVM/Scheduler/Clock/Power improvements
   - ASYNC pageflip support
   - New mesa feature support

  nouveau:
   - GM108 support
   - Power sensor support improvements
   - GR init + ucode fixes.
   - Use GPU provided topology information

  vmwgfx:
   - Add host messaging support

  gma500:
   - Some cleanups and fixes

  atmel:
   - Bridge support
   - Async atomic commit support

  fsl-dcu:
   - Timing controller for LCD support
   - Pixel clock polarity support

  rcar-du:
   - Misc fixes

  exynos:
   - Pipeline clock support
   - Exynoss4533 SoC support
   - HW trigger mode support
   - export HDMI_PHY clock
   - DECON5433 fixes
   - Use generic prime functions
   - use DMA mapping APIs

  rockchip:
   - Lots of little fixes

  vc4:
   - Render node support
   - Gamma ramp support
   - DPI output support

  msm:
   - Mostly cleanups and fixes
   - Conversion to generic struct fence

  etnaviv:
   - Fix for prime buffer handling
   - Allow hangcheck to be coalesced with other wakeups

  tegra:
   - Gamme table size fix"

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (1050 commits)
  drm/edid: add displayid detailed 1 timings to the modelist. (v1.1)
  drm/edid: move displayid validation to it's own function.
  drm/displayid: Iterate over all DisplayID blocks
  drm/edid: move displayid tiled block parsing into separate function.
  drm: Nuke ->vblank_disable_allowed
  drm/vmwgfx: Report vmwgfx version to vmware.log
  drm/vmwgfx: Add VMWare host messaging capability
  drm/vmwgfx: Kill some lockdep warnings
  drm/nouveau/gr/gf100-: fix race condition in fecs/gpccs ucode
  drm/nouveau/core: recognise GM108 chipsets
  drm/nouveau/gr/gm107-: fix touching non-existent ppcs in attrib cb setup
  drm/nouveau/gr/gk104-: share implementation of ppc exception init
  drm/nouveau/gr/gk104-: move rop_active_fbps init to nonctx
  drm/nouveau/bios/pll: check BIT table version before trying to parse it
  drm/nouveau/bios/pll: prevent oops when limits table can't be parsed
  drm/nouveau/volt/gk104: round up in gk104_volt_set
  drm/nouveau/fb/gm200: setup mmu debug buffer registers at init()
  drm/nouveau/fb/gk20a,gm20b: setup mmu debug buffer registers at init()
  drm/nouveau/fb/gf100-: allocate mmu debug buffers
  drm/nouveau/fb: allow chipset-specific actions for oneinit()
  ...
2016-05-23 11:48:48 -07:00
Chris Wilson 80c4bd7a5e mm/vmalloc: keep a separate lazy-free list
When mixing lots of vmallocs and set_memory_*() (which calls
vm_unmap_aliases()) I encountered situations where the performance
degraded severely due to the walking of the entire vmap_area list each
invocation.

One simple improvement is to add the lazily freed vmap_area to a
separate lockless free list, such that we then avoid having to walk the
full list on each purge.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Roman Pen <r.peniaev@gmail.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Roman Pen <r.peniaev@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20 17:58:30 -07:00
Daniel Vetter 3970285319 Linux 4.6-rc3
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Merge tag 'v4.6-rc3' into drm-intel-next-queued

Linux 4.6-rc3

Backmerge requested by Chris Wilson to make his patches apply cleanly.
Tiny conflict in vmalloc.c with the (properly acked and all) patch in
drm-intel-next:

commit 4da56b99d9
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Mon Apr 4 14:46:42 2016 +0100

    mm/vmap: Add a notifier for when we run out of vmap address space

and Linus' tree.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2016-04-11 19:25:13 +02:00
Chris Wilson 4da56b99d9 mm/vmap: Add a notifier for when we run out of vmap address space
vmaps are temporary kernel mappings that may be of long duration.
Reusing a vmap on an object is preferrable for a driver as the cost of
setting up the vmap can otherwise dominate the operation on the object.
However, the vmap address space is rather limited on 32bit systems and
so we add a notification for vmap pressure in order for the driver to
release any cached vmappings.

The interface is styled after the oom-notifier where the callees are
passed a pointer to an unsigned long counter for them to indicate if they
have freed any space.

v2: Guard the blocking notifier call with gfpflags_allow_blocking()
v3: Correct typo in forward declaration and move to head of file

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Roman Peniaev <r.peniaev@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Andrew Morton <akpm@linux-foundation.org> # for inclusion via DRM
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1459777603-23618-3-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2016-04-05 11:12:04 +01:00
Shawn Lin a1c0b1a074 mm/vmalloc: use PAGE_ALIGNED() to check PAGE_SIZE alignment
We have PAGE_ALIGNED() in mm.h, so let's use it instead of IS_ALIGNED()
for checking PAGE_SIZE aligned case.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Joe Perches 756a025f00 mm: coalesce split strings
Kernel style prefers a single string over split strings when the string is
'user-visible'.

Miscellanea:

 - Add a missing newline
 - Realign arguments

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Tejun Heo <tj@kernel.org>	[percpu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Joonsoo Kim f48d97f340 mm/vmalloc: query dynamic DEBUG_PAGEALLOC setting
As CONFIG_DEBUG_PAGEALLOC can be enabled/disabled via kernel parameters
we can optimize some cases by checking the enablement state.

This is follow-up work for Christian's Optimize CONFIG_DEBUG_PAGEALLOC:

  https://lkml.org/lkml/2016/1/27/194

Remaining work is to make sparc to be aware of this but it looks not
easy for me so I skip that in this series.

This patch (of 5):

We can disable debug_pagealloc processing even if the code is complied
with CONFIG_DEBUG_PAGEALLOC.  This patch changes the code to query
whether it is enabled or not in runtime.

[akpm@linux-foundation.org: update comment, per David.  Adjust comment to use 80 cols]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Wang Xiaoqiang 61e165578d mm/vmalloc.c: use macro IS_ALIGNED to judge the aligment
Just cleanup, no functional change.

Signed-off-by: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
David Rientjes 244d63ee34 mm, vmalloc: remove VM_VPAGES
VM_VPAGES is unnecessary, it's easier to check is_vmalloc_addr() when
reading /proc/vmallocinfo.

[akpm@linux-foundation.org: remove VM_VPAGES reference via kvfree()]
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-14 16:00:49 -08:00
Geliang Tang 6219c2a2ec mm/vmalloc.c: use list_{next,first}_entry
To make the intention clearer, use list_{next,first}_entry instead of
list_entry.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-14 16:00:49 -08:00
Vladimir Davydov 37f08dda29 vmalloc: allow to account vmalloc to memcg
Make vmalloc family functions allocate vmalloc area pages with
alloc_kmem_pages so that if __GFP_ACCOUNT is set they will be accounted
to memcg.  This is needed, at least, to account alloc_fdmem allocations.

Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-14 16:00:49 -08:00
Jerome Marchand 7511c3ede7 mm: vmalloc: don't remove inexistent guard hole in remove_vm_area()
Commit 71394fe501 ("mm: vmalloc: add flag preventing guard hole
allocation") missed a spot.  Currently remove_vm_area() decreases vm->size
to "remove" the guard hole page, even when it isn't present.  All but one
users just free the vm_struct rigth away and never access vm->size anyway.

Don't touch the size in remove_vm_area() and have __vunmap() use the
proper get_vm_area_size() helper.

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-20 16:17:32 -08:00
Mel Gorman dd56b04642 mm: page_alloc: hide some GFP internals and document the bits and flag combinations
Andrew stated the following

	We have quite a history of remote parts of the kernel using
	weird/wrong/inexplicable combinations of __GFP_ flags.	I tend
	to think that this is because we didn't adequately explain the
	interface.

	And I don't think that gfp.h really improved much in this area as
	a result of this patchset.  Could you go through it some time and
	decide if we've adequately documented all this stuff?

This patches first moves some GFP flag combinations that are part of the MM
internals to mm/internal.h. The rest of the patch documents the __GFP_FOO
bits under various headings and then documents the flag combinations. It
will not help callers that are brain damaged but the clarity might motivate
some fixes and avoid future mistakes.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Mel Gorman d0164adc89 mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd
__GFP_WAIT has been used to identify atomic context in callers that hold
spinlocks or are in interrupts.  They are expected to be high priority and
have access one of two watermarks lower than "min" which can be referred
to as the "atomic reserve".  __GFP_HIGH users get access to the first
lower watermark and can be called the "high priority reserve".

Over time, callers had a requirement to not block when fallback options
were available.  Some have abused __GFP_WAIT leading to a situation where
an optimisitic allocation with a fallback option can access atomic
reserves.

This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
cannot sleep and have no alternative.  High priority users continue to use
__GFP_HIGH.  __GFP_DIRECT_RECLAIM identifies callers that can sleep and
are willing to enter direct reclaim.  __GFP_KSWAPD_RECLAIM to identify
callers that want to wake kswapd for background reclaim.  __GFP_WAIT is
redefined as a caller that is willing to enter direct reclaim and wake
kswapd for background reclaim.

This patch then converts a number of sites

o __GFP_ATOMIC is used by callers that are high priority and have memory
  pools for those requests. GFP_ATOMIC uses this flag.

o Callers that have a limited mempool to guarantee forward progress clear
  __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
  into this category where kswapd will still be woken but atomic reserves
  are not used as there is a one-entry mempool to guarantee progress.

o Callers that are checking if they are non-blocking should use the
  helper gfpflags_allow_blocking() where possible. This is because
  checking for __GFP_WAIT as was done historically now can trigger false
  positives. Some exceptions like dm-crypt.c exist where the code intent
  is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
  flag manipulations.

o Callers that built their own GFP flags instead of starting with GFP_KERNEL
  and friends now also need to specify __GFP_KSWAPD_RECLAIM.

The first key hazard to watch out for is callers that removed __GFP_WAIT
and was depending on access to atomic reserves for inconspicuous reasons.
In some cases it may be appropriate for them to use __GFP_HIGH.

The second key hazard is callers that assembled their own combination of
GFP flags instead of starting with something like GFP_KERNEL.  They may
now wish to specify __GFP_KSWAPD_RECLAIM.  It's almost certainly harmless
if it's missed in most cases as other activity will wake kswapd.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Alexander Kuleshov 891c49abfb mm/vmalloc: use offset_in_page macro
linux/mm.h provides offset_in_page() macro.  Let's use already predefined
macro instead of (addr & ~PAGE_MASK).

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05 19:34:48 -08:00
Linus Torvalds a5ad88ce8c mm: get rid of 'vmalloc_info' from /proc/meminfo
It turns out that at least some versions of glibc end up reading
/proc/meminfo at every single startup, because glibc wants to know the
amount of memory the machine has.  And while that's arguably insane,
it's just how things are.

And it turns out that it's not all that expensive most of the time, but
the vmalloc information statistics (amount of virtual memory used in the
vmalloc space, and the biggest remaining chunk) can be rather expensive
to compute.

The 'get_vmalloc_info()' function actually showed up on my profiles as
4% of the CPU usage of "make test" in the git source repository, because
the git tests are lots of very short-lived shell-scripts etc.

It turns out that apparently this same silly vmalloc info gathering
shows up on the facebook servers too, according to Dave Jones.  So it's
not just "make test" for git.

We had two patches to just cache the information (one by me, one by
Ingo) to mitigate this issue, but the whole vmalloc information of of
rather dubious value to begin with, and people who *actually* want to
know what the situation is wrt the vmalloc area should just look at the
much more complete /proc/vmallocinfo instead.

In fact, according to my testing - and perhaps more importantly,
according to that big search engine in the sky: Google - there is
nothing out there that actually cares about those two expensive fields:
VmallocUsed and VmallocChunk.

So let's try to just remove them entirely.  Actually, this just removes
the computation and reports the numbers as zero for now, just to try to
be minimally intrusive.

If this breaks anything, we'll obviously have to re-introduce the code
to compute this all and add the caching patches on top.  But if given
the option, I'd really prefer to just remove this bad idea entirely
rather than add even more code to work around our historical mistake
that likely nobody really cares about.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-01 17:09:15 -08:00
Roman Pen 7d61bfe8fd mm/vmalloc: get rid of dirty bitmap inside vmap_block structure
In original implementation of vm_map_ram made by Nick Piggin there were
two bitmaps: alloc_map and dirty_map.  None of them were used as supposed
to be: finding a suitable free hole for next allocation in block.
vm_map_ram allocates space sequentially in block and on free call marks
pages as dirty, so freed space can't be reused anymore.

Actually it would be very interesting to know the real meaning of those
bitmaps, maybe implementation was incomplete, etc.

But long time ago Zhang Yanfei removed alloc_map by these two commits:

  mm/vmalloc.c: remove dead code in vb_alloc
     3fcd76e802
  mm/vmalloc.c: remove alloc_map from vmap_block
     b8e748b6c3

In this patch I replaced dirty_map with two range variables: dirty min and
max.  These variables store minimum and maximum position of dirty space in
a block, since we need only to know the dirty range, not exact position of
dirty pages.

Why it was made?  Several reasons: at first glance it seems that
vm_map_ram allocator concerns about fragmentation thus it uses bitmaps for
finding free hole, but it is not true.  To avoid complexity seems it is
better to use something simple, like min or max range values.  Secondly,
code also becomes simpler, without iteration over bitmap, just comparing
values in min and max macros.  Thirdly, bitmap occupies up to 1024 bits
(4MB is a max size of a block).  Here I replaced the whole bitmap with two
longs.

Finally vm_unmap_aliases should be slightly faster and the whole
vmap_block structure occupies less memory.

Signed-off-by: Roman Pen <r.peniaev@gmail.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Christoph Lameter <cl@linux.com>
Cc: Gioh Kim <gioh.kim@lge.com>
Cc: Rob Jones <rob.jones@codethink.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:18 -07:00
Roman Pen cf725ce274 mm/vmalloc: occupy newly allocated vmap block just after allocation
Previous implementation allocates new vmap block and repeats search of a
free block from the very beginning, iterating over the CPU free list.

Why it can be better??

1. Allocation can happen on one CPU, but search can be done on another CPU.
   In worst case we preallocate amount of vmap blocks which is equal to
   CPU number on the system.

2. In previous patch I added newly allocated block to the tail of free list
   to avoid soon exhaustion of virtual space and give a chance to occupy
   blocks which were allocated long time ago.  Thus to find newly allocated
   block all the search sequence should be repeated, seems it is not efficient.

In this patch newly allocated block is occupied right away, address of
virtual space is returned to the caller, so there is no any need to repeat
the search sequence, allocation job is done.

Signed-off-by: Roman Pen <r.peniaev@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Christoph Lameter <cl@linux.com>
Cc: Gioh Kim <gioh.kim@lge.com>
Cc: Rob Jones <rob.jones@codethink.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:18 -07:00
Roman Pen 68ac546f26 mm/vmalloc: fix possible exhaustion of vmalloc space caused by vm_map_ram allocator
Recently I came across high fragmentation of vm_map_ram allocator:
vmap_block has free space, but still new blocks continue to appear.
Further investigation showed that certain mapping/unmapping sequences
can exhaust vmalloc space.  On small 32bit systems that's not a big
problem, cause purging will be called soon on a first allocation failure
(alloc_vmap_area), but on 64bit machines, e.g.  x86_64 has 45 bits of
vmalloc space, that can be a disaster.

1) I came up with a simple allocation sequence, which exhausts virtual
   space very quickly:

  while (iters) {

                /* Map/unmap big chunk */
                vaddr = vm_map_ram(pages, 16, -1, PAGE_KERNEL);
                vm_unmap_ram(vaddr, 16);

                /* Map/unmap small chunks.
                 *
                 * -1 for hole, which should be left at the end of each block
                 * to keep it partially used, with some free space available */
                for (i = 0; i < (VMAP_BBMAP_BITS - 16) / 8 - 1; i++) {
                        vaddr = vm_map_ram(pages, 8, -1, PAGE_KERNEL);
                        vm_unmap_ram(vaddr, 8);
                }
  }

The idea behind is simple:

 1. We have to map a big chunk, e.g. 16 pages.

 2. Then we have to occupy the remaining space with smaller chunks, i.e.
    8 pages. At the end small hole should remain to keep block in free list,
    but do not let big chunk to occupy remaining space.

 3. Goto 1 - allocation request of 16 pages can't be completed (only 8 slots
    are left free in the block in the #2 step), new block will be allocated,
    all further requests will lay into newly allocated block.

To have some measurement numbers for all further tests I setup ftrace and
enabled 4 basic calls in a function profile:

        echo vm_map_ram              > /sys/kernel/debug/tracing/set_ftrace_filter;
        echo alloc_vmap_area        >> /sys/kernel/debug/tracing/set_ftrace_filter;
        echo vm_unmap_ram           >> /sys/kernel/debug/tracing/set_ftrace_filter;
        echo free_vmap_block        >> /sys/kernel/debug/tracing/set_ftrace_filter;

So for this scenario I got these results:

BEFORE (all new blocks are put to the head of a free list)
# cat /sys/kernel/debug/tracing/trace_stat/function0
  Function                               Hit    Time            Avg             s^2
  --------                               ---    ----            ---             ---
  vm_map_ram                          126000    30683.30 us     0.243 us        30819.36 us
  vm_unmap_ram                        126000    22003.24 us     0.174 us        340.886 us
  alloc_vmap_area                       1000    4132.065 us     4.132 us        0.903 us

AFTER (all new blocks are put to the tail of a free list)
# cat /sys/kernel/debug/tracing/trace_stat/function0
  Function                               Hit    Time            Avg             s^2
  --------                               ---    ----            ---             ---
  vm_map_ram                          126000    28713.13 us     0.227 us        24944.70 us
  vm_unmap_ram                        126000    20403.96 us     0.161 us        1429.872 us
  alloc_vmap_area                        993    3916.795 us     3.944 us        29.370 us
  free_vmap_block                        992    654.157 us      0.659 us        1.273 us

SUMMARY:

The most interesting numbers in those tables are numbers of block
allocations and deallocations: alloc_vmap_area and free_vmap_block
calls, which show that before the change blocks were not freed, and
virtual space and physical memory (vmap_block structure allocations,
etc) were consumed.

Average time which were spent in vm_map_ram/vm_unmap_ram became slightly
better.  That can be explained with a reasonable amount of blocks in a
free list, which we need to iterate to find a suitable free block.

2) Another scenario is a random allocation:

  while (iters) {

                /* Randomly take number from a range [1..32/64] */
                nr = rand(1, VMAP_MAX_ALLOC);
                vaddr = vm_map_ram(pages, nr, -1, PAGE_KERNEL);
                vm_unmap_ram(vaddr, nr);
  }

I chose mersenne twister PRNG to generate persistent random state to
guarantee that both runs have the same random sequence.  For each
vm_map_ram call random number from [1..32/64] was taken to represent
amount of pages which I do map.

I did 10'000 vm_map_ram calls and got these two tables:

BEFORE (all new blocks are put to the head of a free list)

# cat /sys/kernel/debug/tracing/trace_stat/function0
  Function                               Hit    Time            Avg             s^2
  --------                               ---    ----            ---             ---
  vm_map_ram                           10000    10170.01 us     1.017 us        993.609 us
  vm_unmap_ram                         10000    5321.823 us     0.532 us        59.789 us
  alloc_vmap_area                        420    2150.239 us     5.119 us        3.307 us
  free_vmap_block                         37    159.587 us      4.313 us        134.344 us

AFTER (all new blocks are put to the tail of a free list)

# cat /sys/kernel/debug/tracing/trace_stat/function0
  Function                               Hit    Time            Avg             s^2
  --------                               ---    ----            ---             ---
  vm_map_ram                           10000    7745.637 us     0.774 us        395.229 us
  vm_unmap_ram                         10000    5460.573 us     0.546 us        67.187 us
  alloc_vmap_area                        414    2201.650 us     5.317 us        5.591 us
  free_vmap_block                        412    574.421 us      1.394 us        15.138 us

SUMMARY:

'BEFORE' table shows, that 420 blocks were allocated and only 37 were
freed.  Remained 383 blocks are still in a free list, consuming virtual
space and physical memory.

'AFTER' table shows, that 414 blocks were allocated and 412 were really
freed.  2 blocks remained in a free list.

So fragmentation was dramatically reduced.  Why? Because when we put
newly allocated block to the head, all further requests will occupy new
block, regardless remained space in other blocks.  In this scenario all
requests come randomly.  Eventually remained free space will be less
than requested size, free list will be iterated and it is possible that
nothing will be found there - finally new block will be created.  So
exhaustion in random scenario happens for the maximum possible
allocation size: 32 pages for 32-bit system and 64 pages for 64-bit
system.

Also average cost of vm_map_ram was reduced from 1.017 us to 0.774 us.
Again this can be explained by iteration through smaller list of free
blocks.

3) Next simple scenario is a sequential allocation, when the allocation
   order is increased for each block.  This scenario forces allocator to
   reach maximum amount of partially free blocks in a free list:

  while (iters) {

                /* Populate free list with blocks with remaining space */
                for (order = 0; order <= ilog2(VMAP_MAX_ALLOC); order++) {
                        nr = VMAP_BBMAP_BITS / (1 << order);

                        /* Leave a hole */
                        nr -= 1;

                        for (i = 0; i < nr; i++) {
                                vaddr = vm_map_ram(pages, (1 << order), -1, PAGE_KERNEL);
                                vm_unmap_ram(vaddr, (1 << order));
                }

                /* Completely occupy blocks from a free list */
                for (order = 0; order <= ilog2(VMAP_MAX_ALLOC); order++) {
                        vaddr = vm_map_ram(pages, (1 << order), -1, PAGE_KERNEL);
                        vm_unmap_ram(vaddr, (1 << order));
                }
  }

Results which I got:

BEFORE (all new blocks are put to the head of a free list)

# cat /sys/kernel/debug/tracing/trace_stat/function0
  Function                               Hit    Time            Avg             s^2
  --------                               ---    ----            ---             ---
  vm_map_ram                         2032000    399545.2 us     0.196 us        467123.7 us
  vm_unmap_ram                       2032000    363225.7 us     0.178 us        111405.9 us
  alloc_vmap_area                       7001    30627.76 us     4.374 us        495.755 us
  free_vmap_block                       6993    7011.685 us     1.002 us        159.090 us

AFTER (all new blocks are put to the tail of a free list)

# cat /sys/kernel/debug/tracing/trace_stat/function0
  Function                               Hit    Time            Avg             s^2
  --------                               ---    ----            ---             ---
  vm_map_ram                         2032000    394259.7 us     0.194 us        589395.9 us
  vm_unmap_ram                       2032000    292500.7 us     0.143 us        94181.08 us
  alloc_vmap_area                       7000    31103.11 us     4.443 us        703.225 us
  free_vmap_block                       7000    6750.844 us     0.964 us        119.112 us

SUMMARY:

No surprises here, almost all numbers are the same.

Fixing this fragmentation problem I also did some improvements in a
allocation logic of a new vmap block: occupy block immediately and get
rid of extra search in a free list.

Also I replaced dirty bitmap with min/max dirty range values to make the
logic simpler and slightly faster, since two longs comparison costs
less, than loop thru bitmap.

This patchset raises several questions:

 Q: Think the problem you comments is already known so that I wrote comments
    about it as "it could consume lots of address space through fragmentation".
    Could you tell me about your situation and reason why it should be avoided?
                                                                     Gioh Kim

 A: Indeed, there was a commit 364376383 which adds explicit comment about
    fragmentation.  But fragmentation which is described in this comment caused
    by mixing of long-lived and short-lived objects, when a whole block is pinned
    in memory because some page slots are still in use.  But here I am talking
    about blocks which are free, nobody uses them, and allocator keeps them alive
    forever, continuously allocating new blocks.

 Q: I think that if you put newly allocated block to the tail of a free
    list, below example would results in enormous performance degradation.

    new block: 1MB (256 pages)

    while (iters--) {
      vm_map_ram(3 or something else not dividable for 256) * 85
      vm_unmap_ram(3) * 85
    }

    On every iteration, it needs newly allocated block and it is put to the
    tail of a free list so finding it consumes large amount of time.
                                                                    Joonsoo Kim

 A: Second patch in current patchset gets rid of extra search in a free list,
    so new block will be immediately occupied..

    Also, the scenario above is impossible, cause vm_map_ram allocates virtual
    range in orders, i.e. 2^n.  I.e. passing 3 to vm_map_ram you will allocate
    4 slots in a block and 256 slots (capacity of a block) of course dividable
    on 4, so block will be completely occupied.

    But there is a worst case which we can achieve: each free block has a hole
    equal to order size.

    The maximum size of allocation is 64 pages for 64-bit system
    (if you try to map more, original alloc_vmap_area will be called).

    So the maximum order is 6.  That means that worst case, before allocator
    makes a decision to allocate a new block, is to iterate 7 blocks:

    HEAD
    1st block - has 1  page slot  free (order 0)
    2nd block - has 2  page slots free (order 1)
    3rd block - has 4  page slots free (order 2)
    4th block - has 8  page slots free (order 3)
    5th block - has 16 page slots free (order 4)
    6th block - has 32 page slots free (order 5)
    7th block - has 64 page slots free (order 6)
    TAIL

    So the worst scenario on 64-bit system is that each CPU queue can have 7
    blocks in a free list.

    This can happen only and only if you allocate blocks increasing the order.
    (as I did in the function written in the comment of the first patch)
    This is weird and rare case, but still it is possible.  Afterwards you will
    get 7 blocks in a list.

    All further requests should be placed in a newly allocated block or some
    free slots should be found in a free list.
    Seems it does not look dramatically awful.

This patch (of 3):

If suitable block can't be found, new block is allocated and put into a
head of a free list, so on next iteration this new block will be found
first.

That's bad, because old blocks in a free list will not get a chance to be
fully used, thus fragmentation will grow.

Let's consider this simple example:

 #1 We have one block in a free list which is partially used, and where only
    one page is free:

    HEAD |xxxxxxxxx-| TAIL
                   ^
                   free space for 1 page, order 0

 #2 New allocation request of order 1 (2 pages) comes, new block is allocated
    since we do not have free space to complete this request. New block is put
    into a head of a free list:

    HEAD |----------|xxxxxxxxx-| TAIL

 #3 Two pages were occupied in a new found block:

    HEAD |xx--------|xxxxxxxxx-| TAIL
          ^
          two pages mapped here

 #4 New allocation request of order 0 (1 page) comes.  Block, which was created
    on #2 step, is located at the beginning of a free list, so it will be found
    first:

  HEAD |xxX-------|xxxxxxxxx-| TAIL
          ^                 ^
          page mapped here, but better to use this hole

It is obvious, that it is better to complete request of #4 step using the
old block, where free space is left, because in other case fragmentation
will be highly increased.

But fragmentation is not only the case.  The worst thing is that I can
easily create scenario, when the whole vmalloc space is exhausted by
blocks, which are not used, but already dirty and have several free pages.

Let's consider this function which execution should be pinned to one CPU:

static void exhaust_virtual_space(struct page *pages[16], int iters)
{
        /* Firstly we have to map a big chunk, e.g. 16 pages.
         * Then we have to occupy the remaining space with smaller
         * chunks, i.e. 8 pages. At the end small hole should remain.
         * So at the end of our allocation sequence block looks like
         * this:
         *                XX  big chunk
         * |XXxxxxxxx-|    x  small chunk
         *                 -  hole, which is enough for a small chunk,
         *                    but is not enough for a big chunk
         */
        while (iters--) {
                int i;
                void *vaddr;

                /* Map/unmap big chunk */
                vaddr = vm_map_ram(pages, 16, -1, PAGE_KERNEL);
                vm_unmap_ram(vaddr, 16);

                /* Map/unmap small chunks.
                 *
                 * -1 for hole, which should be left at the end of each block
                 * to keep it partially used, with some free space available */
                for (i = 0; i < (VMAP_BBMAP_BITS - 16) / 8 - 1; i++) {
                        vaddr = vm_map_ram(pages, 8, -1, PAGE_KERNEL);
                        vm_unmap_ram(vaddr, 8);
                }
        }
}

On every iteration new block (1MB of vm area in my case) will be
allocated and then will be occupied, without attempt to resolve small
allocation request using previously allocated blocks in a free list.

In case of random allocation (size should be randomly taken from the
range [1..64] in 64-bit case or [1..32] in 32-bit case) situation is the
same: new blocks continue to appear if maximum possible allocation size
(32 or 64) passed to the allocator, because all remaining blocks in a
free list do not have enough free space to complete this allocation
request.

In summary if new blocks are put into the head of a free list eventually
virtual space will be exhausted.

In current patch I simply put newly allocated block to the tail of a
free list, thus reduce fragmentation, giving a chance to resolve
allocation request using older blocks with possible holes left.

Signed-off-by: Roman Pen <r.peniaev@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Christoph Lameter <cl@linux.com>
Cc: Gioh Kim <gioh.kim@lge.com>
Cc: Rob Jones <rob.jones@codethink.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:18 -07:00
Toshi Kani b9820d8f39 mm: change vunmap to tear down huge KVA mappings
Change vunmap_pmd_range() and vunmap_pud_range() to tear down huge KVA
mappings when they are set.  pud_clear_huge() and pmd_clear_huge() return
zero when no-operation is performed, i.e.  huge page mapping was not used.

These changes are only enabled when CONFIG_HAVE_ARCH_HUGE_VMAP is defined
on the architecture.

[akpm@linux-foundation.org: use consistent code layout]
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:49:04 -07:00
Toshi Kani 0f616be120 mm: change __get_vm_area_node() to use fls_long()
ioremap() and its related interfaces are used to create I/O mappings to
memory-mapped I/O devices.  The mapping sizes of the traditional I/O
devices are relatively small.  Non-volatile memory (NVM), however, has
many GB and is going to have TB soon.  It is not very efficient to create
large I/O mappings with 4KB.

This patchset extends the ioremap() interfaces to transparently create I/O
mappings with huge pages whenever possible.  ioremap() continues to use
4KB mappings when a huge page does not fit into a requested range.  There
is no change necessary to the drivers using ioremap().  A requested
physical address must be aligned by a huge page size (1GB or 2MB on x86)
for using huge page mapping, though.  The kernel huge I/O mapping will
improve performance of NVM and other devices with large memory, and reduce
the time to create their mappings as well.

On x86, MTRRs can override PAT memory types with a 4KB granularity.  When
using a huge page, MTRRs can override the memory type of the huge page,
which may lead a performance penalty.  The processor can also behave in an
undefined manner if a huge page is mapped to a memory range that MTRRs
have mapped with multiple different memory types.  Therefore, the mapping
code falls back to use a smaller page size toward 4KB when a mapping range
is covered by non-WB type of MTRRs.  The WB type of MTRRs has no affect on
the PAT memory types.

The patchset introduces HAVE_ARCH_HUGE_VMAP, which indicates that the arch
supports huge KVA mappings for ioremap().  User may specify a new kernel
option "nohugeiomap" to disable the huge I/O mapping capability of
ioremap() when necessary.

Patch 1-4 change common files to support huge I/O mappings.  There is no
change in the functinalities unless HAVE_ARCH_HUGE_VMAP is defined on the
architecture of the system.

Patch 5-6 implement the HAVE_ARCH_HUGE_VMAP funcs on x86, and set
HAVE_ARCH_HUGE_VMAP on x86.

This patch (of 6):

__get_vm_area_node() takes unsigned long size, which is a 64-bit value on
a 64-bit kernel.  However, fls(size) simply ignores the upper 32-bit.
Change to use fls_long() to handle the size properly.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:49:04 -07:00
Andrey Ryabinin a5af5aa8b6 kasan, module, vmalloc: rework shadow allocation for modules
Current approach in handling shadow memory for modules is broken.

Shadow memory could be freed only after memory shadow corresponds it is no
longer used.  vfree() called from interrupt context could use memory its
freeing to store 'struct llist_node' in it:

    void vfree(const void *addr)
    {
    ...
        if (unlikely(in_interrupt())) {
            struct vfree_deferred *p = this_cpu_ptr(&vfree_deferred);
            if (llist_add((struct llist_node *)addr, &p->list))
                    schedule_work(&p->wq);

Later this list node used in free_work() which actually frees memory.
Currently module_memfree() called in interrupt context will free shadow
before freeing module's memory which could provoke kernel crash.

So shadow memory should be freed after module's memory.  However, such
deallocation order could race with kasan_module_alloc() in module_alloc().

Free shadow right before releasing vm area.  At this point vfree()'d
memory is not used anymore and yet not available for other allocations.
New VM_KASAN flag used to indicate that vm area has dynamically allocated
shadow memory so kasan frees shadow only if it was previously allocated.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-03-12 18:46:08 -07:00
Andrey Ryabinin cb9e3c292d mm: vmalloc: pass additional vm_flags to __vmalloc_node_range()
For instrumenting global variables KASan will shadow memory backing memory
for modules.  So on module loading we will need to allocate memory for
shadow and map it at address in shadow that corresponds to the address
allocated in module_alloc().

__vmalloc_node_range() could be used for this purpose, except it puts a
guard hole after allocated area.  Guard hole in shadow memory should be a
problem because at some future point we might need to have a shadow memory
at address occupied by guard hole.  So we could fail to allocate shadow
for module_alloc().

Now we have VM_NO_GUARD flag disabling guard page, so we need to pass into
__vmalloc_node_range().  Add new parameter 'vm_flags' to
__vmalloc_node_range() function.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:42 -08:00
Andrey Ryabinin 71394fe501 mm: vmalloc: add flag preventing guard hole allocation
For instrumenting global variables KASan will shadow memory backing memory
for modules.  So on module loading we will need to allocate memory for
shadow and map it at address in shadow that corresponds to the address
allocated in module_alloc().

__vmalloc_node_range() could be used for this purpose, except it puts a
guard hole after allocated area.  Guard hole in shadow memory should be a
problem because at some future point we might need to have a shadow memory
at address occupied by guard hole.  So we could fail to allocate shadow
for module_alloc().

Add a new vm_struct flag 'VM_NO_GUARD' indicating that vm area doesn't
have a guard hole.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrey Konovalov <adech.fo@gmail.com>
Cc: Yuri Gribov <tetra2005@gmail.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:42 -08:00
Dmitry Vyukov 7e5b528b4c mm/vmalloc.c: fix memory ordering bug
Read memory barriers must follow the read operations.

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 12:42:49 -08:00
Pintu Kumar 0cbc8533b7 mm/vmalloc.c: replace printk with pr_warn
This patch replaces printk(KERN_WARNING..) with pr_warn.
Thus it also reduces one line extra because of formatting.

Signed-off-by: Pintu Kumar <pintu.k@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10 17:41:05 -08:00
Rob Jones 703394c100 mm/vmalloc.c: use seq_open_private() instead of seq_open()
Using seq_open_private() removes boilerplate code from vmalloc_open().

The resultant code is shorter and easier to follow.

However, please note that seq_open_private() call kzalloc() rather than
kmalloc() which may affect timing due to the memory initialisation
overhead.

Signed-off-by: Rob Jones <rob.jones@codethink.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09 22:25:56 -04:00
WANG Chao f6f8ed4735 mm/vmalloc.c: clean up map_vm_area third argument
Currently map_vm_area() takes (struct page *** pages) as third argument,
and after mapping, it moves (*pages) to point to (*pages +
nr_mappped_pages).

It looks like this kind of increment is useless to its caller these
days.  The callers don't care about the increments and actually they're
trying to avoid this by passing another copy to map_vm_area().

The caller can always guarantee all the pages can be mapped into vm_area
as specified in first argument and the caller only cares about whether
map_vm_area() fails or not.

This patch cleans up the pointer movement in map_vm_area() and updates
its callers accordingly.

Signed-off-by: WANG Chao <chaowang@redhat.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:19 -07:00
David Rientjes 930f036b4f mm, vmalloc: constify allocation mask
tmp_mask in the __vmalloc_area_node() iteration never changes so it can
be moved into function scope and marked with const.  This causes the
movl and orl to only be done once per call rather than area->nr_pages
times.

nested_gfp can also be marked const.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:18 -07:00
Eric Dumazet 660654f90e mm/vmalloc.c: add a schedule point to vmalloc()
It is not uncommon on busy servers to get stuck hundred of ms in
vmalloc() calls (like file descriptor expansions).

Add a cond_resched() to __vmalloc_area_node() to be gentle to
other tasks.

[akpm@linux-foundation.org: only do it for __GFP_WAIT, per David]
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Hugh Dickins <hughd@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:18 -07:00
Joonsoo Kim 474750aba8 vmalloc: use rcu list iterator to reduce vmap_area_lock contention
Richard Yao reported a month ago that his system have a trouble with
vmap_area_lock contention during performance analysis by /proc/meminfo.
Andrew asked why his analysis checks /proc/meminfo stressfully, but he
didn't answer it.

  https://lkml.org/lkml/2014/4/10/416

Although I'm not sure that this is right usage or not, there is a
solution reducing vmap_area_lock contention with no side-effect.  That
is just to use rcu list iterator in get_vmalloc_info().

rcu can be used in this function because all RCU protocol is already
respected by writers, since Nick Piggin commit db64fe0225 ("mm:
rewrite vmap layer") back in linux-2.6.28

Specifically :
   insertions use list_add_rcu(),
   deletions use list_del_rcu() and kfree_rcu().

Note the rb tree is not used from rcu reader (it would not be safe),
only the vmap_area_list has full RCU protection.

Note that __purge_vmap_area_lazy() already uses this rcu protection.

        rcu_read_lock();
        list_for_each_entry_rcu(va, &vmap_area_list, list) {
                if (va->flags & VM_LAZY_FREE) {
                        if (va->va_start < *start)
                                *start = va->va_start;
                        if (va->va_end > *end)
                                *end = va->va_end;
                        nr += (va->va_end - va->va_start) >> PAGE_SHIFT;
                        list_add_tail(&va->purge_list, &valist);
                        va->flags |= VM_LAZY_FREEING;
                        va->flags &= ~VM_LAZY_FREE;
                }
        }
        rcu_read_unlock();

Peter:

: While rcu list traversal over the vmap_area_list is safe, this may
: arrive at different results than the spinlocked version. The rcu list
: traversal version will not be a 'snapshot' of a single, valid instant
: of the entire vmap_area_list, but rather a potential amalgam of
: different list states.

Joonsoo:

: Yes, you are right, but I don't think that we should be strict here.
: Meminfo is already not a 'snapshot' at specific time.  While we try to get
: certain stats, the other stats can change.  And, although we may arrive at
: different results than the spinlocked version, the difference would not be
: large and would not make serious side-effect.

[edumazet@google.com: add more commit description]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reported-by: Richard Yao <ryao@gentoo.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Zhang Yanfei <zhangyanfei.yes@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:15 -07:00
Minchan Kim 93ef6d6ca1 mm/vmalloc.c: export unmap_kernel_range()
zsmalloc needs exported unmap_kernel_range for building as a module.  See
https://lkml.org/lkml/2013/1/18/487

I didn't send a patch to make unmap_kernel_range exportable at that time
because zram was staging stuff and I thought VM function exporting for
staging stuff makes no sense.

Now zsmalloc was promoted.  If we can't build zsmalloc as module, it means
we can't build zram as module, either.  Additionally, buddy map_vm_area is
already exported so let's export unmap_kernel_range to help his buddy.

Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:14 -07:00
Fabian Frederick f4527c9086 mm/vmalloc.c: replace seq_printf by seq_puts
Replace seq_printf where possible

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:04 -07:00
Christoph Lameter 7c8e0181e6 mm: replace __get_cpu_var uses with this_cpu_ptr
Replace places where __get_cpu_var() is used for an address calculation
with this_cpu_ptr().

Signed-off-by: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:03 -07:00
Gioh Kim 3643763834 mm/vmalloc.c: enhance vm_map_ram() comment
vm_map_ram() has a fragmentation problem when it cannot purge a
chunk(ie, 4M address space) if there is a pinning object in that
addresss space.  So it could consume all VMALLOC address space easily.

We can fix the fragmentation problem by using vmap instead of
vm_map_ram() but vmap() is known to be slow compared to vm_map_ram().
Minchan said vm_map_ram is 5 times faster than vmap in his tests.  So I
thought we should fix fragment problem of vm_map_ram because our
proprietary GPU driver has used it heavily.

On second thought, it's not an easy because we should reuse freed space
for solving the problem and it could make more IPI and bitmap operation
for searching hole.  It could mitigate API's goal which is very fast
mapping.  And even fragmentation problem wouldn't show in 64 bit
machine.

Another option is that the user should separate long-life and short-life
object and use vmap for long-life but vm_map_ram for short-life.  If we
inform the user about the characteristic of vm_map_ram the user can
choose one according to the page lifetime.

Let's add some notice messages to user.

[akpm@linux-foundation.org: tweak comment text]
Signed-off-by: Gioh Kim <gioh.kim@lge.com>
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:35:55 -07:00
Gideon Israel Dsouza 3b32123d73 mm: use macros from compiler.h instead of __attribute__((...))
To increase compiler portability there is <linux/compiler.h> which
provides convenience macros for various gcc constructs.  Eg: __weak for
__attribute__((weak)).  I've replaced all instances of gcc attributes with
the right macro in the memory management (/mm) subsystem.

[akpm@linux-foundation.org: while-we're-there consistency tweaks]
Signed-off-by: Gideon Israel Dsouza <gidisrael@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:35:54 -07:00
malc add688fbd3 Revert "mm/vmalloc: interchage the implementation of vmalloc_to_{pfn,page}"
Revert commit ece86e222d, which was intended as a small performance
improvement.

Despite the claim that the patch doesn't introduce any functional
changes in fact it does.

The "no page" path behaves different now.  Originally, vmalloc_to_page
might return NULL under some conditions, with new implementation it
returns pfn_to_page(0) which is not the same as NULL.

Simple test shows the difference.

test.c

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>

int __init myi(void)
{
	struct page *p;
	void *v;

	v = vmalloc(PAGE_SIZE);
	/* trigger the "no page" path in vmalloc_to_page*/
	vfree(v);

	p = vmalloc_to_page(v);

	pr_err("expected val = NULL, returned val = %p", p);

	return -EBUSY;
}

void __exit mye(void)
{

}
module_init(myi)
module_exit(mye)

Before interchange:
expected val = NULL, returned val =   (null)

After interchange:
expected val = NULL, returned val = c7ebe000

Signed-off-by: Vladimir Murzin <murzin.v@gmail.com>
Cc: Jianyu Zhan <nasa4836@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-27 21:02:39 -08:00
Jianyu Zhan ece86e222d mm/vmalloc: interchage the implementation of vmalloc_to_{pfn,page}
Currently we are implementing vmalloc_to_pfn() as a wrapper around
vmalloc_to_page(), which is implemented as follow:

 1. walks the page talbes to generates the corresponding pfn,
 2. then converts the pfn to struct page,
 3. returns it.

And vmalloc_to_pfn() re-wraps vmalloc_to_page() to get the pfn.

This seems too circuitous, so this patch reverses the way: implement
vmalloc_to_page() as a wrapper around vmalloc_to_pfn().  This makes
vmalloc_to_pfn() and vmalloc_to_page() slightly more efficient.

No functional change.

Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Cc: Vladimir Murzin <murzin.v@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:44 -08:00
Catalin Marinas 7f88f88f83 mm: kmemleak: avoid false negatives on vmalloc'ed objects
Commit 248ac0e194 ("mm/vmalloc: remove guard page from between vmap
blocks") had the side effect of making vmap_area.va_end member point to
the next vmap_area.va_start.  This was creating an artificial reference
to vmalloc'ed objects and kmemleak was rarely reporting vmalloc() leaks.

This patch marks the vmap_area containing pointers explicitly and
reduces the min ref_count to 2 as vm_struct still contains a reference
to the vmalloc'ed object.  The kmemleak add_scan_area() function has
been improved to allow a SIZE_MAX argument covering the rest of the
object (for simpler calling sites).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:07 +09:00
Wanpeng Li b82225f3ff revert mm/vmalloc.c: emit the failure message before return
Don't warn twice in __vmalloc_area_node and __vmalloc_node_range if
__vmalloc_area_node allocation failure.  This patch reverts commit
46c001a275 ("mm/vmalloc.c: emit the failure message before return").

Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:05 +09:00
Wanpeng Li af12346cda mm/vmalloc: revert "mm/vmalloc.c: check VM_UNINITIALIZED flag in s_show instead of show_numa_info"
The VM_UNINITIALIZED/VM_UNLIST flag introduced by f5252e009d ("mm:
avoid null pointer access in vm_struct via /proc/vmallocinfo") is used
to avoid accessing the pages field with unallocated page when
show_numa_info() is called.

This patch moves the check just before show_numa_info in order that some
messages still can be dumped via /proc/vmallocinfo.  This patch reverts
commit d157a55815 ("mm/vmalloc.c: check VM_UNINITIALIZED flag in
s_show instead of show_numa_info");

Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:05 +09:00
Wanpeng Li c2ce8c142c mm/vmalloc: fix show vmap_area information race with vmap_area tear down
There is a race window between vmap_area tear down and show vmap_area
information.

	A                                                B

remove_vm_area
spin_lock(&vmap_area_lock);
va->vm = NULL;
va->flags &= ~VM_VM_AREA;
spin_unlock(&vmap_area_lock);
						spin_lock(&vmap_area_lock);
						if (va->flags & (VM_LAZY_FREE | VM_LAZY_FREEZING))
							return 0;
						if (!(va->flags & VM_VM_AREA)) {
							seq_printf(m, "0x%pK-0x%pK %7ld vm_map_ram\n",
								(void *)va->va_start, (void *)va->va_end,
								va->va_end - va->va_start);
							return 0;
						}
free_unmap_vmap_area(va);
	flush_cache_vunmap
	free_unmap_vmap_area_noflush
		unmap_vmap_area
		free_vmap_area_noflush
			va->flags |= VM_LAZY_FREE

The assumption !VM_VM_AREA represents vm_map_ram allocation is
introduced by d4033afdf8 ("mm, vmalloc: iterate vmap_area_list,
instead of vmlist, in vmallocinfo()").

However, !VM_VM_AREA also represents vmap_area is being tear down in
race window mentioned above.  This patch fix it by don't dump any
information for !VM_VM_AREA case and also remove (VM_LAZY_FREE |
VM_LAZY_FREEING) check since they are not possible for !VM_VM_AREA case.

Suggested-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:05 +09:00
Wanpeng Li 3722e13cff mm/vmalloc: don't set area->caller twice
The caller address has already been set in set_vmalloc_vm(), there's no
need to set it again in __vmalloc_area_node.

Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:05 +09:00
Jianguo Wu 4b90951c0b mm/vmalloc: use NUMA_NO_NODE
Use more appropriate "if (node == NUMA_NO_NODE)" instead of "if (node < 0)"

Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:02 +09:00
Wanpeng Li 762216ab4e mm/vmalloc: use wrapper function get_vm_area_size to caculate size of vm area
Use wrapper function get_vm_area_size to calculate size of vm area.

Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:58:02 -07:00
Joonsoo Kim b136be5e0b mm, vmalloc: use well-defined find_last_bit() func
Our intention in here is to find last_bit within the region to flush.
There is well-defined function, find_last_bit() for this purpose and its
performance may be slightly better than current implementation.  So change
it.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:57:34 -07:00
Joonsoo Kim 6b70f7dff8 mm, vmalloc: remove useless variable in vmap_block
vbq in vmap_block isn't used. So remove it.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:57:33 -07:00
Zhang Yanfei bcb615a81b mm/vmalloc.c: fix an overflow bug in alloc_vmap_area()
When searching a vmap area in the vmalloc space, we use (addr + size -
1) to check if the value is less than addr, which is an overflow.  But
we assign (addr + size) to vmap_area->va_end.

So if we come across the below case:

  (addr + size - 1) : not overflow
  (addr + size)     : overflow

we will assign an overflow value (e.g 0) to vmap_area->va_end, And this
will trigger BUG in __insert_vmap_area, causing system panic.

So using (addr + size) to check the overflow should be the correct
behaviour, not (addr + size - 1).

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Reported-by: Ghennadi Procopciuc <unix140@gmail.com>
Tested-by: Daniel Baluta <dbaluta@ixiacom.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:23 -07:00
Oleg Nesterov 59d3132f8a vfree: don't schedule free_work() if llist_add() returns false
vfree() only needs schedule_work(&p->wq) if p->list was empty, otherwise
vfree_deferred->wq is already pending or it is running and didn't do
llist_del_all() yet.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:22 -07:00
Zhang Yanfei d157a55815 mm/vmalloc.c: check VM_UNINITIALIZED flag in s_show instead of show_numa_info
We should check the VM_UNITIALIZED flag in s_show().  If this flag is
set, that said, the vm_struct is not fully initialized.  So it is
unnecessary to try to show the information contained in vm_struct.

We checked this flag in show_numa_info(), but I think it's better to
check it earlier.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:21 -07:00
Zhang Yanfei 20fc02b477 mm/vmalloc.c: rename VM_UNLIST to VM_UNINITIALIZED
VM_UNLIST was used to indicate that the vm_struct is not listed in
vmlist.

But after commit 4341fa4547 ("mm, vmalloc: remove list management of
vmlist after initializing vmalloc"), the meaning of this flag changed.
It now means the vm_struct is not fully initialized.  So renaming it to
VM_UNINITIALIZED seems more reasonable.

Also change clear_vm_unlist to clear_vm_uninitialized_flag.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:21 -07:00
Zhang Yanfei 46c001a275 mm/vmalloc.c: emit the failure message before return
Use goto to jump to the fail label to give a failure message before
returning NULL.  This makes the failure handling in this function
consistent.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:21 -07:00
Zhang Yanfei b8e748b6c3 mm/vmalloc.c: remove alloc_map from vmap_block
As we have removed the dead code in the vb_alloc, it seems there is no
place to use the alloc_map.  So there is no reason to maintain the
alloc_map in vmap_block.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:21 -07:00
Zhang Yanfei 9da3f59fbd mm/vmalloc.c: remove unused purge_fragmented_blocks_thiscpu
This function is nowhere used now, so remove it.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:21 -07:00
Zhang Yanfei 3fcd76e802 mm/vmalloc.c: remove dead code in vb_alloc
Space in a vmap block that was once allocated is considered dirty and
not made available for allocation again before the whole block is
recycled.  The result is that free space within a vmap block is always
contiguous.

So if a vmap block has enough free space for allocation, the allocation
is impossible to fail.  Thus, the fragmented block purging was never
invoked from vb_alloc().  So remove this dead code.

[ Same patches also sent by:

    Chanho Min <chanho.min@lge.com>
    Johannes Weiner <hannes@cmpxchg.org>

  but git doesn't do "multiple authors" ]

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:20 -07:00
Dan Carpenter ab15d9b4cb mm/vmalloc.c: unbreak __vunmap()
There is an extra semi-colon so the function always returns.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:20 -07:00
Zhang Yanfei 0f2d4a8e27 mm, vmalloc: use clamp() to simplify code
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:40 -07:00
Zhang Yanfei f6d480059b mm, vmalloc: remove insert_vmalloc_vm()
Now this function is nowhere used, we can remove it directly.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:40 -07:00
Zhang Yanfei 3645cb4a4e mm, vmalloc: call setup_vmalloc_vm() instead of insert_vmalloc_vm()
Here we pass flags with only VM_ALLOC bit set, it is unnecessary to call
clear_vm_unlist to clear VM_UNLIST bit.  So use setup_vmalloc_vm instead
of insert_vmalloc_vm.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:40 -07:00
Zhang Yanfei d82b1d8576 mm, vmalloc: only call setup_vmalloc_vm() only in __get_vm_area_node()
Now for insert_vmalloc_vm, it only calls the two functions:

 - setup_vmalloc_vm: fill vm_struct and vmap_area instances
 - clear_vm_unlist: clear VM_UNLIST bit in vm_struct->flags

So in __get_vm_area_node(), if VM_UNLIST bit unset in flags, that is the
else branch here, we don't need to clear VM_UNLIST bit for vm->flags since
this bit is obviously not set.  That is to say, we could only call
setup_vmalloc_vm instead of insert_vmalloc_vm here.  And then we could
even remove the if test here.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:40 -07:00
HATAYAMA Daisuke e69e9d4aee vmalloc: introduce remap_vmalloc_range_partial
We want to allocate ELF note segment buffer on the 2nd kernel in vmalloc
space and remap it to user-space in order to reduce the risk that memory
allocation fails on system with huge number of CPUs and so with huge ELF
note segment that exceeds 11-order block size.

Although there's already remap_vmalloc_range for the purpose of
remapping vmalloc memory to user-space, we need to specify user-space
range via vma.
 Mmap on /proc/vmcore needs to remap range across multiple objects, so
the interface that requires vma to cover full range is problematic.

This patch introduces remap_vmalloc_range_partial that receives user-space
range as a pair of base address and size and can be used for mmap on
/proc/vmcore case.

remap_vmalloc_range is rewritten using remap_vmalloc_range_partial.

[akpm@linux-foundation.org: use PAGE_ALIGNED()]
Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Lisa Mitchell <lisa.mitchell@hp.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:30 -07:00
HATAYAMA Daisuke cef2ac3f6c vmalloc: make find_vm_area check in range
Currently, __find_vmap_area searches for the kernel VM area starting at
a given address.  This patch changes this behavior so that it searches
for the kernel VM area to which the address belongs.  This change is
needed by remap_vmalloc_range_partial to be introduced in later patch
that receives any position of kernel VM area as target address.

This patch changes the condition (addr > va->va_start) to the equivalent
(addr >= va->va_end) by taking advantage of the fact that each kernel VM
area is non-overlapping.

Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Lisa Mitchell <lisa.mitchell@hp.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:30 -07:00
Andrew Morton c9fcee5132 mm/vmalloc.c: add vfree comment
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 18:38:27 -07:00
Linus Torvalds 20b4fb4852 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS updates from Al Viro,

Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).

7kloc removed.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
  don't bother with deferred freeing of fdtables
  proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
  proc: Make the PROC_I() and PDE() macros internal to procfs
  proc: Supply a function to remove a proc entry by PDE
  take cgroup_open() and cpuset_open() to fs/proc/base.c
  ppc: Clean up scanlog
  ppc: Clean up rtas_flash driver somewhat
  hostap: proc: Use remove_proc_subtree()
  drm: proc: Use remove_proc_subtree()
  drm: proc: Use minor->index to label things, not PDE->name
  drm: Constify drm_proc_list[]
  zoran: Don't print proc_dir_entry data in debug
  reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
  proc: Supply an accessor for getting the data from a PDE's parent
  airo: Use remove_proc_subtree()
  rtl8192u: Don't need to save device proc dir PDE
  rtl8187se: Use a dir under /proc/net/r8180/
  proc: Add proc_mkdir_data()
  proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
  proc: Move PDE_NET() to fs/proc/proc_net.c
  ...
2013-05-01 17:51:54 -07:00
Atsushi Kumagai 13ba3fcbbe kexec, vmalloc: export additional vmalloc layer information
Now, vmap_area_list is exported as VMCOREINFO for makedumpfile to get
the start address of vmalloc region (vmalloc_start).  The address which
contains vmalloc_start value is represented as below:

  vmap_area_list.next - OFFSET(vmap_area.list) + OFFSET(vmap_area.va_start)

However, both OFFSET(vmap_area.va_start) and OFFSET(vmap_area.list)
aren't exported as VMCOREINFO.

So this patch exports them externally with small cleanup.

[akpm@linux-foundation.org: vmalloc.h should include list.h for list_head]
Signed-off-by: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:34 -07:00
Joonsoo Kim 4341fa4547 mm, vmalloc: remove list management of vmlist after initializing vmalloc
Now, there is no need to maintain vmlist after initializing vmalloc.  So
remove related code and data structure.

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:34 -07:00
Joonsoo Kim f1c4069e1d mm, vmalloc: export vmap_area_list, instead of vmlist
Although our intention is to unexport internal structure entirely, but
there is one exception for kexec.  kexec dumps address of vmlist and
makedumpfile uses this information.

We are about to remove vmlist, then another way to retrieve information
of vmalloc layer is needed for makedumpfile.  For this purpose, we
export vmap_area_list, instead of vmlist.

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:34 -07:00
Joonsoo Kim d4033afdf8 mm, vmalloc: iterate vmap_area_list, instead of vmlist, in vmallocinfo()
This patch is a preparatory step for removing vmlist entirely.  For
above purpose, we change iterating a vmap_list codes to iterating a
vmap_area_list.  It is somewhat trivial change, but just one thing
should be noticed.

Using vmap_area_list in vmallocinfo() introduce ordering problem in SMP
system.  In s_show(), we retrieve some values from vm_struct.
vm_struct's values is not fully setup when va->vm is assigned.  Full
setup is notified by removing VM_UNLIST flag without holding a lock.
When we see that VM_UNLIST is removed, it is not ensured that vm_struct
has proper values in view of other CPUs.  So we need smp_[rw]mb for
ensuring that proper values is assigned when we see that VM_UNLIST is
removed.

Therefore, this patch not only change a iteration list, but also add a
appropriate smp_[rw]mb to right places.

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:34 -07:00
Joonsoo Kim f98782ddd3 mm, vmalloc: iterate vmap_area_list in get_vmalloc_info()
This patch is a preparatory step for removing vmlist entirely.  For
above purpose, we change iterating a vmap_list codes to iterating a
vmap_area_list.  It is somewhat trivial change, but just one thing
should be noticed.

vmlist is lack of information about some areas in vmalloc address space.
For example, vm_map_ram() allocate area in vmalloc address space, but it
doesn't make a link with vmlist.  To provide full information about
vmalloc address space is better idea, so we don't use va->vm and use
vmap_area directly.  This makes get_vmalloc_info() more precise.

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:34 -07:00
Joonsoo Kim e81ce85f96 mm, vmalloc: iterate vmap_area_list, instead of vmlist in vread/vwrite()
Now, when we hold a vmap_area_lock, va->vm can't be discarded.  So we can
safely access to va->vm when iterating a vmap_area_list with holding a
vmap_area_lock.  With this property, change iterating vmlist codes in
vread/vwrite() to iterating vmap_area_list.

There is a little difference relate to lock, because vmlist_lock is mutex,
but, vmap_area_lock is spin_lock.  It may introduce a spinning overhead
during vread/vwrite() is executing.  But, these are debug-oriented
functions, so this overhead is not real problem for common case.

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:34 -07:00
Joonsoo Kim c69480adee mm, vmalloc: protect va->vm by vmap_area_lock
Inserting and removing an entry to vmlist is linear time complexity, so
it is inefficient.  Following patches will try to remove vmlist
entirely.  This patch is preparing step for it.

For removing vmlist, iterating vmlist codes should be changed to
iterating a vmap_area_list.  Before implementing that, we should make
sure that when we iterate a vmap_area_list, accessing to va->vm doesn't
cause a race condition.  This patch ensure that when iterating a
vmap_area_list, there is no race condition for accessing to vm_struct.

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:33 -07:00
Joonsoo Kim db3808c1ba mm, vmalloc: move get_vmalloc_info() to vmalloc.c
Now get_vmalloc_info() is in fs/proc/mmu.c.  There is no reason that this
code must be here and it's implementation needs vmlist_lock and it iterate
a vmlist which may be internal data structure for vmalloc.

It is preferable that vmlist_lock and vmlist is only used in vmalloc.c
for maintainability. So move the code to vmalloc.c

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:33 -07:00
Al Viro 32fcfd4071 make vfree() safe to call from interrupt contexts
A bunch of RCU callbacks want to be able to do vfree() and end up with
rather kludgy schemes.  Just let vfree() do the right thing - put the
victim on llist and schedule actual __vunmap() via schedule_work(), so
that it runs from non-interrupt context.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-10 21:18:21 -04:00
David Rientjes 00ef2d2f84 mm: use NUMA_NO_NODE
Make a sweep through mm/ and convert code that uses -1 directly to using
the more appropriate NUMA_NO_NODE.

Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 17:50:21 -08:00
Kirill A. Shutemov e5adfffc85 mm: use IS_ENABLED(CONFIG_NUMA) instead of NUMA_BUILD
We don't need custom NUMA_BUILD anymore, since we have handy
IS_ENABLED().

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-11 17:22:22 -08:00
Kees Cook 45ec16908e mm: use %pK for /proc/vmallocinfo
In the paranoid case of sysctl kernel.kptr_restrict=2, mask the kernel
virtual addresses in /proc/vmallocinfo too.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Brad Spengler <spender@grsecurity.net>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:23:03 +09:00
Konstantin Khlebnikov 314e51b985 mm: kill vma flag VM_RESERVED and mm->reserved_vm counter
A long time ago, in v2.4, VM_RESERVED kept swapout process off VMA,
currently it lost original meaning but still has some effects:

 | effect                 | alternative flags
-+------------------------+---------------------------------------------
1| account as reserved_vm | VM_IO
2| skip in core dump      | VM_IO, VM_DONTDUMP
3| do not merge or expand | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP
4| do not mlock           | VM_IO, VM_DONTEXPAND, VM_HUGETLB, VM_PFNMAP

This patch removes reserved_vm counter from mm_struct.  Seems like nobody
cares about it, it does not exported into userspace directly, it only
reduces total_vm showed in proc.

Thus VM_RESERVED can be replaced with VM_IO or pair VM_DONTEXPAND | VM_DONTDUMP.

remap_pfn_range() and io_remap_pfn_range() set VM_IO|VM_DONTEXPAND|VM_DONTDUMP.
remap_vmalloc_range() set VM_DONTEXPAND | VM_DONTDUMP.

[akpm@linux-foundation.org: drivers/vfio/pci/vfio_pci.c fixup]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:22:19 +09:00
Jan Kara aa91c4d898 mm: make vb_alloc() more foolproof
If someone calls vb_alloc() (or vm_map_ram() for that matter) to allocate
0 bytes (0 pages), get_order() returns BITS_PER_LONG - PAGE_CACHE_SHIFT
and interesting stuff happens.  So make debugging such problems easier and
warn about 0-size allocation.

[akpm@linux-foundation.org: use WARN_ON-return-value feature]
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 18:42:39 -07:00
Hong zhi guo 92ca922f0a vmalloc: walk vmap_areas by sorted list instead of rb_next()
There's a walk by repeating rb_next to find a suitable hole.  Could be
simply replaced by walk on the sorted vmap_area_list.  More simpler and
efficient.

Mutation of the list and tree only happens in pair within
__insert_vmap_area and __free_vmap_area, under protection of
vmap_area_lock.  The patch code is also under vmap_area_lock, so the list
walk is safe, and consistent with the tree walk.

Tested on SMP by repeating batch of vmalloc anf vfree for random sizes and
rounds for hours.

Signed-off-by: Hong Zhiguo <honkiko@gmail.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 18:42:39 -07:00
Linus Torvalds 6f51f51582 Merge branch 'for-linus-for-3.6-rc1' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping
Pull DMA-mapping updates from Marek Szyprowski:
 "Those patches are continuation of my earlier work.

  They contains extensions to DMA-mapping framework to remove limitation
  of the current ARM implementation (like limited total size of DMA
  coherent/write combine buffers), improve performance of buffer sharing
  between devices (attributes to skip cpu cache operations or creation
  of additional kernel mapping for some specific use cases) as well as
  some unification of the common code for dma_mmap_attrs() and
  dma_mmap_coherent() functions.  All extensions have been implemented
  and tested for ARM architecture."

* 'for-linus-for-3.6-rc1' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
  ARM: dma-mapping: add support for DMA_ATTR_SKIP_CPU_SYNC attribute
  common: DMA-mapping: add DMA_ATTR_SKIP_CPU_SYNC attribute
  ARM: dma-mapping: add support for dma_get_sgtable()
  common: dma-mapping: introduce dma_get_sgtable() function
  ARM: dma-mapping: add support for DMA_ATTR_NO_KERNEL_MAPPING attribute
  common: DMA-mapping: add DMA_ATTR_NO_KERNEL_MAPPING attribute
  common: dma-mapping: add support for generic dma_mmap_* calls
  ARM: dma-mapping: fix error path for memory allocation failure
  ARM: dma-mapping: add more sanity checks in arm_dma_mmap()
  ARM: dma-mapping: remove custom consistent dma region
  mm: vmalloc: use const void * for caller argument
  scatterlist: add sg_alloc_table_from_pages function
2012-07-30 10:11:31 -07:00
Marek Szyprowski e9da6e9905 ARM: dma-mapping: remove custom consistent dma region
This patch changes dma-mapping subsystem to use generic vmalloc areas
for all consistent dma allocations. This increases the total size limit
of the consistent allocations and removes platform hacks and a lot of
duplicated code.

Atomic allocations are served from special pool preallocated on boot,
because vmalloc areas cannot be reliably created in atomic context.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
2012-07-30 12:25:45 +02:00
Marek Szyprowski 5e6cafc83e mm: vmalloc: use const void * for caller argument
'const void *' is a safer type for caller function type. This patch
updates all references to caller function type.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
2012-07-30 12:25:44 +02:00
Cong Wang a8e5202d09 vmalloc: remove KM_USER0 from comments
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-07-24 15:27:33 +08:00
KyongHo dbda591d92 mm: fix faulty initialization in vmalloc_init()
The transfer of ->flags causes some of the static mapping virtual
addresses to be prematurely freed (before the mapping is removed) because
VM_LAZY_FREE gets "set" if tmp->flags has VM_IOREMAP set.  This might
cause subsequent vmalloc/ioremap calls to fail because it might allocate
one of the freed virtual address ranges that aren't unmapped.

va->flags has different types of flags from tmp->flags.  If a region with
VM_IOREMAP set is registered with vm_area_add_early(), it will be removed
by __purge_vmap_area_lazy().

Fix vmalloc_init() to correctly initialize vmap_area for the given
vm_struct.

Also initialise va->vm.  If it is not set, find_vm_area() for the early
vm regions will always fail.

Signed-off-by: KyongHo Cho <pullip.cho@samsung.com>
Cc: "Olav Haugan" <ohaugan@codeaurora.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29 16:22:24 -07:00
Thomas Meyer 4d67d86053 mm: use kcalloc() instead of kzalloc() to allocate array
The advantage of kcalloc is, that will prevent integer overflows which
could result from the multiplication of number of elements and size and
it is also a bit nicer to read.

The semantic patch that makes this change is available in
https://lkml.org/lkml/2011/11/25/107

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29 16:22:19 -07:00
Cong Wang 9b04c5fec4 mm: remove the second argument of k[un]map_atomic()
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-20 21:48:27 +08:00
Kautuk Consul f1db7afd91 mm/vmalloc.c: eliminate extra loop in pcpu_get_vm_areas error path
If either of the vas or vms arrays are not properly kzalloced, then the
code jumps to the err_free label.

The err_free label runs a loop to check and free each of the array members
of the vas and vms arrays which is not required for this situation as none
of the array members have been allocated till this point.

Eliminate the extra loop we have to go through by introducing a new label
err_free2 and then jumping to it.

[akpm@linux-foundation.org: remove now-unneeded tests]
Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-12 20:13:10 -08:00
Minchan Kim db1aecafef mm/vmalloc.c: change void* into explict vm_struct*
vmap_area->private is void* but we don't use the field for various purpose
but use only for vm_struct.  So change it to a vm_struct* with naming to
improve for readability and type checking.

Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:46 -08:00
Russell King 2e0e943436 Merge branch 'devel-stable' into for-linus
Conflicts:
	arch/arm/kernel/setup.c
	arch/arm/mach-shmobile/board-kota2.c
2012-01-05 13:24:33 +00:00
Kautuk Consul 0006526d78 mm/vmalloc.c: remove static declaration of va from __get_vm_area_node
Static storage is not required for the struct vmap_area in
__get_vm_area_node.

Removing "static" to store this variable on the stack instead.

Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-20 10:25:04 -08:00
Mel Gorman 1368edf064 mm: vmalloc: check for page allocation failure before vmlist insertion
Commit f5252e00 ("mm: avoid null pointer access in vm_struct via
/proc/vmallocinfo") adds newly allocated vm_structs to the vmlist after
it is fully initialised.  Unfortunately, it did not check that
__vmalloc_area_node() successfully populated the area.  In the event of
allocation failure, the vmalloc area is freed but the pointer to freed
memory is inserted into the vmlist leading to a a crash later in
get_vmalloc_info().

This patch adds a check for ____vmalloc_area_node() failure within
__vmalloc_node_range.  It does not use "goto fail" as in the previous
error path as a warning was already displayed by __vmalloc_area_node()
before it called vfree in its failure path.

Credit goes to Luciano Chavez for doing all the real work of identifying
exactly where the problem was.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Luciano Chavez <lnx1138@linux.vnet.ibm.com>
Tested-by: Luciano Chavez <lnx1138@linux.vnet.ibm.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>		[3.1.x+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-12-09 07:50:29 -08:00
Russell King 73829af71f Merge branch 'vmalloc' of git://git.linaro.org/people/nico/linux into devel-stable 2011-12-05 23:27:59 +00:00
Nicolas Pitre be9b7335e7 mm: add vm_area_add_early()
The existing vm_area_register_early() allows for early vmalloc space
allocation.  However upcoming cleanups in the ARM architecture require
that some fixed locations in the vmalloc area be reserved also very early.

The name "vm_area_register_early" would have been a good name for the
reservation part without the allocation.  Since it is already in use with
different semantics, let's create vm_area_add_early() instead.

Both vm_area_register_early() and vm_area_add_early() can be used together
meaning that the former is now implemented using the later where it is
ensured that no conflicting areas are added, but no attempt is made to
make the allocation scheme in vm_area_register_early() more sophisticated.
After all, you must know what you're doing when using those functions.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org
2011-11-18 13:51:22 -05:00
David Vrabel cd12909cb5 xen: map foreign pages for shared rings by updating the PTEs directly
When mapping a foreign page with xenbus_map_ring_valloc() with the
GNTTABOP_map_grant_ref hypercall, set the GNTMAP_contains_pte flag and
pass a pointer to the PTE (in init_mm).

After the page is mapped, the usual fault mechanism can be used to
update additional MMs.  This allows the vmalloc_sync_all() to be
removed from alloc_vm_area().

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
[v1: Squashed fix by Michal for no-mmu case]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
2011-11-16 12:13:08 -05:00
Joe Perches de7d2b567d mm/vmalloc.c: report more vmalloc failures
Some vmalloc failure paths do not report OOM conditions.

Add warn_alloc_failed, which also does a dump_stack, to those failure
paths.

This allows more site specific vmalloc failure logging message printks to
be removed.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:48 -07:00
Joe Perches 3ee9a4f086 mm: neaten warn_alloc_failed
Add __attribute__((format (printf...) to the function to validate format
and arguments.  Use vsprintf extension %pV to avoid any possible message
interleaving.  Coalesce format string.  Convert printks/pr_warning to
pr_warn.

[akpm@linux-foundation.org: use the __printf() macro]
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:48 -07:00
Mitsuo Hayasaka f5252e009d mm: avoid null pointer access in vm_struct via /proc/vmallocinfo
The /proc/vmallocinfo shows information about vmalloc allocations in
vmlist that is a linklist of vm_struct.  It, however, may access pages
field of vm_struct where a page was not allocated.  This results in a null
pointer access and leads to a kernel panic.

Why this happens: In __vmalloc_node_range() called from vmalloc(), newly
allocated vm_struct is added to vmlist at __get_vm_area_node() and then,
some fields of vm_struct such as nr_pages and pages are set at
__vmalloc_area_node().  In other words, it is added to vmlist before it is
fully initialized.  At the same time, when the /proc/vmallocinfo is read,
it accesses the pages field of vm_struct according to the nr_pages field
at show_numa_info().  Thus, a null pointer access happens.

The patch adds the newly allocated vm_struct to the vmlist *after* it is
fully initialized.  So, it can avoid accessing the pages field with
unallocated page when show_numa_info() is called.

Signed-off-by: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: <stable@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:47 -07:00
David Vrabel 461ae488ec mm: sync vmalloc address space page tables in alloc_vm_area()
Xen backend drivers (e.g., blkback and netback) would sometimes fail to
map grant pages into the vmalloc address space allocated with
alloc_vm_area().  The GNTTABOP_map_grant_ref would fail because Xen could
not find the page (in the L2 table) containing the PTEs it needed to
update.

(XEN) mm.c:3846:d0 Could not find L1 PTE for address fbb42000

netback and blkback were making the hypercall from a kernel thread where
task->active_mm != &init_mm and alloc_vm_area() was only updating the page
tables for init_mm.  The usual method of deferring the update to the page
tables of other processes (i.e., after taking a fault) doesn't work as a
fault cannot occur during the hypercall.

This would work on some systems depending on what else was using vmalloc.

Fix this by reverting ef691947d8 ("vmalloc: remove vmalloc_sync_all()
from alloc_vm_area()") and add a comment to explain why it's needed.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Keir Fraser <keir.xen@gmail.com>
Cc: <stable@kernel.org>		[3.0.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-14 18:09:38 -07:00
Clemens Ladisch f982f91516 mm: fix wrong vmap address calculations with odd NR_CPUS values
Commit db64fe0225 ("mm: rewrite vmap layer") introduced code that does
address calculations under the assumption that VMAP_BLOCK_SIZE is a
power of two.  However, this might not be true if CONFIG_NR_CPUS is not
set to a power of two.

Wrong vmap_block index/offset values could lead to memory corruption.
However, this has never been observed in practice (or never been
diagnosed correctly); what caught this was the BUG_ON in vb_alloc() that
checks for inconsistent vmap_block indices.

To fix this, ensure that VMAP_BLOCK_SIZE always is a power of two.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=31572
Reported-by: Pavel Kysilka <goldenfish@linuxsoft.cz>
Reported-by: Matias A. Fonzo <selk@dragora.org>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: 2.6.28+ <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-14 12:32:52 -07:00
Arun Sharma 60063497a9 atomic: use <linux/atomic.h>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:47 -07:00
Lai Jiangshan 22a3c7d188 vmalloc,rcu: Convert call_rcu(rcu_free_vb) to kfree_rcu()
The rcu callback rcu_free_vb() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(rcu_free_vb).

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-07-20 14:10:18 -07:00
Lai Jiangshan 14769de93f vmalloc,rcu: Convert call_rcu(rcu_free_va) to kfree_rcu()
The rcu callback rcu_free_va() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(rcu_free_va).

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-07-20 14:10:17 -07:00
Linus Torvalds dc7acbb251 Merge branch 'upstream/tidy-xen-mmu-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'upstream/tidy-xen-mmu-2.6.39' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen: fix compile without CONFIG_XEN_DEBUG_FS
  Use arbitrary_virt_to_machine() to deal with ioremapped pud updates.
  Use arbitrary_virt_to_machine() to deal with ioremapped pmd updates.
  xen/mmu: remove all ad-hoc stats stuff
  xen: use normal virt_to_machine for ptes
  xen: make a pile of mmu pvop functions static
  vmalloc: remove vmalloc_sync_all() from alloc_vm_area()
  xen: condense everything onto xen_set_pte
  xen: use mmu_update for xen_set_pte_at()
  xen: drop all the special iomap pte paths.
2011-05-26 19:01:15 -07:00
Dave Hansen 22943ab116 mm: print vmalloc() state after allocation failures
I was tracking down a page allocation failure that ended up in vmalloc().
Since vmalloc() uses 0-order pages, if somebody asks for an insane amount
of memory, we'll still get a warning with "order:0" in it.  That's not
very useful.

During recovery, vmalloc() also nicely frees all of the memory that it got
up to the point of the failure.  That is wonderful, but it also quickly
hides any issues.  We have a much different sitation if vmalloc()
repeatedly fails 10GB in to:

	vmalloc(100 * 1<<30);

versus repeatedly failing 4096 bytes in to a:

	vmalloc(8192);

This patch will print out messages that look like this:

[   68.123503] vmalloc: allocation failure, allocated 6680576 of 13426688 bytes
[   68.124218] bash: page allocation failure: order:0, mode:0xd2
[   68.124811] Pid: 3770, comm: bash Not tainted 2.6.39-rc3-00082-g85f2e68-dirty #333
[   68.125579] Call Trace:
[   68.125853]  [<ffffffff810f6da6>] warn_alloc_failed+0x146/0x170
[   68.126464]  [<ffffffff8107e05c>] ? printk+0x6c/0x70
[   68.126791]  [<ffffffff8112b5d4>] ? alloc_pages_current+0x94/0xe0
[   68.127661]  [<ffffffff8111ed37>] __vmalloc_node_range+0x237/0x290
...

The 'order' variable is added for clarity when calling warn_alloc_failed()
to avoid having an unexplained '0' as an argument.

The 'tmp_mask' is because adding an open-coded '| __GFP_NOWARN' would take
us over 80 columns for the alloc_pages_node() call.  If we are going to
add a line, it might as well be one that makes the sucker easier to read.

As a side issue, I also noticed that ctl_ioctl() does vmalloc() based
solely on an unverified value passed in from userspace.  Granted, it's
under CAP_SYS_ADMIN, but it still frightens me a bit.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:22 -07:00
Johannes Weiner 248ac0e194 mm/vmalloc: remove guard page from between vmap blocks
The vmap allocator is used to, among other things, allocate per-cpu vmap
blocks, where each vmap block is naturally aligned to its own size.
Obviously, leaving a guard page after each vmap area forbids packing vmap
blocks efficiently and can make the kernel run out of possible vmap blocks
long before overall vmap space is exhausted.

The new interface to map a user-supplied page array into linear vmalloc
space (vm_map_ram) insists on allocating from a vmap block (instead of
falling back to a custom area) when the area size is below a certain
threshold.  With heavy users of this interface (e.g.  XFS) and limited
vmalloc space on 32-bit, vmap block exhaustion is a real problem.

Remove the guard page from the core vmap allocator.  vmalloc and the old
vmap interface enforce a guard page on their own at a higher level.

Note that without this patch, we had accidental guard pages after those
vm_map_ram areas that happened to be at the end of a vmap block, but not
between every area.  This patch removes this accidental guard page only.

If we want guard pages after every vm_map_ram area, this should be done
separately.  And just like with vmalloc and the old interface on a
different level, not in the core allocator.

Mel pointed out: "If necessary, the guard page could be reintroduced as a
debugging-only option (CONFIG_DEBUG_PAGEALLOC?).  Otherwise it seems
reasonable."

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Dave Chinner <david@fromorbit.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:11 -07:00
Jeremy Fitzhardinge ef691947d8 vmalloc: remove vmalloc_sync_all() from alloc_vm_area()
There's no need for it: it will get faulted into the current pagetable
as needed.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-05-20 14:14:32 -07:00
Namhyung Kim a42931bf9c vmalloc: remove confusing comment on vwrite()
KM_USER1 is never used for vwrite() path so the caller doesn't need to
guarantee it is not used.  Only the caller should guarantee is KM_USER0
and it is commented already.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:09 -07:00
Nick Piggin 89699605fe mm: vmap area cache
Provide a free area cache for the vmalloc virtual address allocator, based
on the algorithm used by the user virtual memory allocator.

This reduces the number of rbtree operations and linear traversals over
the vmap extents in order to find a free area, by starting off at the last
point that a free area was found.

The free area cache is reset if areas are freed behind it, or if we are
searching for a smaller area or alignment than last time.  So allocation
patterns are not changed (verified by corner-case and random test cases in
userspace testing).

This solves a regression caused by lazy vunmap TLB purging introduced in
db64fe02 (mm: rewrite vmap layer).  That patch will leave extents in the
vmap allocator after they are vunmapped, and until a significant number
accumulate that can be flushed in a single batch.  So in a workload that
vmalloc/vfree frequently, a chain of extents will build up from
VMALLOC_START address, which have to be iterated over each time (giving an
O(n) type of behaviour).

After this patch, the search will start from where it left off, giving
closer to an amortized O(1).

This is verified to solve regressions reported Steven in GFS2, and Avi in
KVM.

Hugh's update:

: I tried out the recent mmotm, and on one machine was fortunate to hit
: the BUG_ON(first->va_start < addr) which seems to have been stalling
: your vmap area cache patch ever since May.

: I can get you addresses etc, I did dump a few out; but once I stared
: at them, it was easier just to look at the code: and I cannot see how
: you would be so sure that first->va_start < addr, once you've done
: that addr = ALIGN(max(...), align) above, if align is over 0x1000
: (align was 0x8000 or 0x4000 in the cases I hit: ioremaps like Steve).

: I originally got around it by just changing the
: 		if (first->va_start < addr) {
: to
: 		while (first->va_start < addr) {
: without thinking about it any further; but that seemed unsatisfactory,
: why would we want to loop here when we've got another very similar
: loop just below it?

: I am never going to admit how long I've spent trying to grasp your
: "while (n)" rbtree loop just above this, the one with the peculiar
: 		if (!first && tmp->va_start < addr + size)
: in.  That's unfamiliar to me, I'm guessing it's designed to save a
: subsequent rb_next() in a few circumstances (at risk of then setting
: a wrong cached_hole_size?); but they did appear few to me, and I didn't
: feel I could sign off something with that in when I don't grasp it,
: and it seems responsible for extra code and mistaken BUG_ON below it.

: I've reverted to the familiar rbtree loop that find_vma() does (but
: with va_end >= addr as you had, to respect the additional guard page):
: and then (given that cached_hole_size starts out 0) I don't see the
: need for any complications below it.  If you do want to keep that loop
: as you had it, please add a comment to explain what it's trying to do,
: and where addr is relative to first when you emerge from it.

: Aren't your tests "size <= cached_hole_size" and
: "addr + size > first->va_start" forgetting the guard page we want
: before the next area?  I've changed those.

: I have not changed your many "addr + size - 1 < addr" overflow tests,
: but have since come to wonder, shouldn't they be "addr + size < addr"
: tests - won't the vend checks go wrong if addr + size is 0?

: I have added a few comments - Wolfgang Wander's 2.6.13 description of
: 1363c3cd86 Avoiding mmap fragmentation
: helped me a lot, perhaps a pointer to that would be good too.  And I found
: it easier to understand when I renamed cached_start slightly and moved the
: overflow label down.

: This patch would go after your mm-vmap-area-cache.patch in mmotm.
: Trivially, nobody is going to get that BUG_ON with this patch, and it
: appears to work fine on my machines; but I have not given it anything like
: the testing you did on your original, and may have broken all the
: performance you were aiming for.  Please take a look and test it out
: integrate with yours if you're satisfied - thanks.

[akpm@linux-foundation.org: add locking comment]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reported-and-tested-by: Steven Whitehouse <swhiteho@redhat.com>
Reported-and-tested-by: Avi Kivity <avi@redhat.com>
Tested-by: "Barry J. Marson" <bmarson@redhat.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Linus Torvalds 52cfd503ad Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (59 commits)
  ACPI / PM: Fix build problems for !CONFIG_ACPI related to NVS rework
  ACPI: fix resource check message
  ACPI / Battery: Update information on info notification and resume
  ACPI: Drop device flag wake_capable
  ACPI: Always check if _PRW is present before trying to evaluate it
  ACPI / PM: Check status of power resources under mutexes
  ACPI / PM: Rename acpi_power_off_device()
  ACPI / PM: Drop acpi_power_nocheck
  ACPI / PM: Drop acpi_bus_get_power()
  Platform / x86: Make fujitsu_laptop use acpi_bus_update_power()
  ACPI / Fan: Rework the handling of power resources
  ACPI / PM: Register power resource devices as soon as they are needed
  ACPI / PM: Register acpi_power_driver early
  ACPI / PM: Add function for updating device power state consistently
  ACPI / PM: Add function for device power state initialization
  ACPI / PM: Introduce __acpi_bus_get_power()
  ACPI / PM: Introduce function for refcounting device power resources
  ACPI / PM: Add functions for manipulating lists of power resources
  ACPI / PM: Prevent acpi_power_get_inferred_state() from making changes
  ACPICA: Update version to 20101209
  ...
2011-01-13 20:15:35 -08:00
Tobias Klauser ddf9c6d472 vmalloc: remove redundant unlikely()
IS_ERR() already implies unlikely(), so it can be omitted here.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:36 -08:00
David Rientjes d0a21265df mm: unify module_alloc code for vmalloc
Four architectures (arm, mips, sparc, x86) use __vmalloc_area() for
module_init().  Much of the code is duplicated and can be generalized in a
globally accessible function, __vmalloc_node_range().

__vmalloc_node() now calls into __vmalloc_node_range() with a range of
[VMALLOC_START, VMALLOC_END) for functionally equivalent behavior.

Each architecture may then use __vmalloc_node_range() directly to remove
the duplication of code.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:34 -08:00
David Rientjes ec3f64fc9c mm: remove gfp mask from pcpu_get_vm_areas
pcpu_get_vm_areas() only uses GFP_KERNEL allocations, so remove the gfp_t
formal and use the mask internally.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:34 -08:00
David Rientjes e5a5623b28 mm: remove unused get_vm_area_node
get_vm_area_node() is unused in the kernel and can thus be removed.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:34 -08:00
Joe Perches 62c70bce8a mm: convert sprintf_symbol to %pS
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Jiri Kosina <trivial@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:33 -08:00
Huang Ying 81e88fdc43 ACPI, APEI, Generic Hardware Error Source POLL/IRQ/NMI notification type support
Generic Hardware Error Source provides a way to report platform
hardware errors (such as that from chipset). It works in so called
"Firmware First" mode, that is, hardware errors are reported to
firmware firstly, then reported to Linux by firmware. This way, some
non-standard hardware error registers or non-standard hardware link
can be checked by firmware to produce more valuable hardware error
information for Linux.

This patch adds POLL/IRQ/NMI notification types support.

Because the memory area used to transfer hardware error information
from BIOS to Linux can be determined only in NMI, IRQ or timer
handler, but general ioremap can not be used in atomic context, so a
special version of atomic ioremap is implemented for that.

Known issue:

- Error information can not be printed for recoverable errors notified
  via NMI, because printk is not NMI-safe. Will fix this via delay
  printing to IRQ context via irq_work or make printk NMI-safe.

v2:

- adjust printk format per comments.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2011-01-12 03:06:19 -05:00
Jeremy Fitzhardinge 64141da587 vmalloc: eagerly clear ptes on vunmap
On stock 2.6.37-rc4, running:

  # mount lilith:/export /mnt/lilith
  # find  /mnt/lilith/ -type f -print0 | xargs -0 file

crashes the machine fairly quickly under Xen.  Often it results in oops
messages, but the couple of times I tried just now, it just hung quietly
and made Xen print some rude messages:

    (XEN) mm.c:2389:d80 Bad type (saw 7400000000000001 != exp
    3000000000000000) for mfn 1d7058 (pfn 18fa7)
    (XEN) mm.c:964:d80 Attempt to create linear p.t. with write perms
    (XEN) mm.c:2389:d80 Bad type (saw 7400000000000010 != exp
    1000000000000000) for mfn 1d2e04 (pfn 1d1fb)
    (XEN) mm.c:2965:d80 Error while pinning mfn 1d2e04

Which means the domain tried to map a pagetable page RW, which would
allow it to map arbitrary memory, so Xen stopped it.  This is because
vm_unmap_ram() left some pages mapped in the vmalloc area after NFS had
finished with them, and those pages got recycled as pagetable pages
while still having these RW aliases.

Removing those mappings immediately removes the Xen-visible aliases, and
so it has no problem with those pages being reused as pagetable pages.
Deferring the TLB flush doesn't upset Xen because it can flush the TLB
itself as needed to maintain its invariants.

When unmapping a region in the vmalloc space, clear the ptes
immediately.  There's no point in deferring this because there's no
amortization benefit.

The TLBs are left dirty, and they are flushed lazily to amortize the
cost of the IPIs.

This specific motivation for this patch is an oops-causing regression
since 2.6.36 when using NFS under Xen, triggered by the NFS client's use
of vm_map_ram() introduced in 56e4ebf877 ("NFS: readdir with vmapped
pages") .  XFS also uses vm_map_ram() and could cause similar problems.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Bryan Schumaker <bjschuma@netapp.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Alex Elder <aelder@sgi.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-02 14:51:15 -08:00
Dave Young e1ca7788de mm: add vzalloc() and vzalloc_node() helpers
Add vzalloc() and vzalloc_node() to encapsulate the
vmalloc-then-memset-zero operation.

Use __GFP_ZERO to zero fill the allocated memory.

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Greg Ungerer <gerg@snapgear.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:10 -07:00
Namhyung Kim e199b5d1fe vmalloc: annotate lock context change on s_start/stop()
s_start() and s_stop() grab/release vmlist_lock but were missing proper
annotations.  Add them.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:10 -07:00
Namhyung Kim 170168d0a3 vmalloc: rename temporary variable in __insert_vmap_area()
Rename redundant 'tmp' to fix following sparse warnings:

 mm/vmalloc.c:296:34: warning: symbol 'tmp' shadows an earlier one
 mm/vmalloc.c:293:24: originally declared here

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:10 -07:00
Linus Torvalds 0fc0531e0a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: update comments to reflect that percpu allocations are always zero-filled
  percpu: Optimize __get_cpu_var()
  x86, percpu: Optimize this_cpu_ptr
  percpu: clear memory allocated with the km allocator
  percpu: fix build breakage on s390 and cleanup build configuration tests
  percpu: use percpu allocator on UP too
  percpu: reduce PCPU_MIN_UNIT_SIZE to 32k
  vmalloc: pcpu_get/free_vm_areas() aren't needed on UP

Fixed up trivial conflicts in include/linux/percpu.h
2010-10-22 17:31:36 -07:00
Cliff Wickman 3ee48b6af4 mm, x86: Saving vmcore with non-lazy freeing of vmas
During the reading of /proc/vmcore the kernel is doing
ioremap()/iounmap() repeatedly. And the buildup of un-flushed
vm_area_struct's is causing a great deal of overhead. (rb_next()
is chewing up most of that time).

This solution is to provide function set_iounmap_nonlazy(). It
causes a subsequent call to iounmap() to immediately purge the
vma area (with try_purge_vmap_area_lazy()).

With this patch we have seen the time for writing a 250MB
compressed dump drop from 71 seconds to 44 seconds.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: kexec@lists.infradead.org
Cc: <stable@kernel.org>
LKML-Reference: <E1OwHZ4-0005WK-Tw@eag09.americas.sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-17 09:11:56 +02:00
Tejun Heo 4f8b02b4e5 vmalloc: pcpu_get/free_vm_areas() aren't needed on UP
These functions are used only by percpu memory allocator on SMP.
Don't build them on UP.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Reviewed-by: Chrsitoph Lameter <cl@linux.com>
2010-09-08 11:10:47 +02:00
Linus Torvalds 26f0cf9181 Merge branch 'stable/xen-swiotlb-0.8.6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/xen-swiotlb-0.8.6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  x86: Detect whether we should use Xen SWIOTLB.
  pci-swiotlb-xen: Add glue code to setup dma_ops utilizing xen_swiotlb_* functions.
  swiotlb-xen: SWIOTLB library for Xen PV guest with PCI passthrough.
  xen/mmu: inhibit vmap aliases rather than trying to clear them out
  vmap: add flag to allow lazy unmap to be disabled at runtime
  xen: Add xen_create_contiguous_region
  xen: Rename the balloon lock
  xen: Allow unprivileged Xen domains to create iomap pages
  xen: use _PAGE_IOMAP in ioremap to do machine mappings

Fix up trivial conflicts (adding both xen swiotlb and xen pci platform
driver setup close to each other) in drivers/xen/{Kconfig,Makefile} and
include/xen/xen-ops.h
2010-08-12 09:09:41 -07:00
Kulikov Vasiliy 51980ac9e7 mm/vmalloc.c: check kmalloc() return value
kmalloc() may fail, if so return -ENOMEM.

Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:45:03 -07:00
Julia Lawall e7d8634079 mm: use ERR_CAST
Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)).  The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
type T;
T x;
identifier f;
@@

T f (...) { <+...
- ERR_PTR(PTR_ERR(x))
+ x
 ...+> }

@@
expression x;
@@

- ERR_PTR(PTR_ERR(x))
+ ERR_CAST(x)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09 20:44:54 -07:00
Jeremy Fitzhardinge a0d40c8025 vmap: add flag to allow lazy unmap to be disabled at runtime
Add a flag to force lazy_max_pages() to zero to prevent any outstanding
mapped pages.  We'll need this for Xen.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Nick Piggin <npiggin@suse.de>
2010-07-27 11:49:09 -04:00
Kenji Kaneshige ffa71f33a8 x86, ioremap: Fix incorrect physical address handling in PAE mode
Current x86 ioremap() doesn't handle physical address higher than
32-bit properly in X86_32 PAE mode. When physical address higher than
32-bit is passed to ioremap(), higher 32-bits in physical address is
cleared wrongly. Due to this bug, ioremap() can map wrong address to
linear address space.

In my case, 64-bit MMIO region was assigned to a PCI device (ioat
device) on my system. Because of the ioremap()'s bug, wrong physical
address (instead of MMIO region) was mapped to linear address space.
Because of this, loading ioatdma driver caused unexpected behavior
(kernel panic, kernel hangup, ...).

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
LKML-Reference: <4C1AE680.7090408@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-07-09 11:42:03 -07:00
Nick Piggin 02b709df81 mm: purge fragmented percpu vmap blocks
Improve handling of fragmented per-CPU vmaps.  We previously don't free
up per-CPU maps until all its addresses have been used and freed.  So
fragmented blocks could fill up vmalloc space even if they actually had
no active vmap regions within them.

Add some logic to allow all CPUs to have these blocks purged in the case
of failure to allocate a new vm area, and also put some logic to trim
such blocks of a current CPU if we hit them in the allocation path (so
as to avoid a large build up of them).

Christoph reported some vmap allocation failures when using the per CPU
vmap APIs in XFS, which cannot be reproduced after this patch and the
previous bug fix.

Cc: linux-mm@kvack.org
Cc: stable@kernel.org
Tested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Nick Piggin <npiggin@suse.de>
--
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-02-02 12:50:47 -08:00
Nick Piggin de5604231c mm: percpu-vmap fix RCU list walking
RCU list walking of the per-cpu vmap cache was broken.  It did not use
RCU primitives, and also the union of free_list and rcu_head is
obviously wrong (because free_list is indeed the list we are RCU
walking).

While we are there, remove a couple of unused fields from an earlier
iteration.

These APIs aren't actually used anywhere, because of problems with the
XFS conversion.  Christoph has now verified that the problems are solved
with these patches.  Also it is an exported interface, so I think it
will be good to be merged now (and Christoph wants to get the XFS
changes into their local tree).

Cc: stable@kernel.org
Cc: linux-mm@kvack.org
Tested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Nick Piggin <npiggin@suse.de>
--
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-02-02 12:50:47 -08:00
Yongseok Koh 88f5004430 vmalloc: remove BUG_ON due to racy counting of VM_LAZY_FREE
In free_unmap_area_noflush(), va->flags is marked as VM_LAZY_FREE first, and
then vmap_lazy_nr is increased atomically.

But, in __purge_vmap_area_lazy(), while traversing of vmap_are_list, nr
is counted by checking VM_LAZY_FREE is set to va->flags.  After counting
the variable nr, kernel reads vmap_lazy_nr atomically and checks a
BUG_ON condition whether nr is greater than vmap_lazy_nr to prevent
vmap_lazy_nr from being negative.

The problem is that, if interrupted right after marking VM_LAZY_FREE,
increment of vmap_lazy_nr can be delayed.  Consequently, BUG_ON
condition can be met because nr is counted more than vmap_lazy_nr.

It is highly probable when vmalloc/vfree are called frequently.  This
scenario have been verified by adding delay between marking VM_LAZY_FREE
and increasing vmap_lazy_nr in free_unmap_area_noflush().

Even the vmap_lazy_nr is for checking high watermark, it never be the
strict watermark.  Although the BUG_ON condition is to prevent
vmap_lazy_nr from being negative, vmap_lazy_nr is signed variable.  So,
it could go down to negative value temporarily.

Consequently, removing the BUG_ON condition is proper.

A possible BUG_ON message is like the below.

   kernel BUG at mm/vmalloc.c:517!
   invalid opcode: 0000 [#1] SMP
   EIP: 0060:[<c04824a4>] EFLAGS: 00010297 CPU: 3
   EIP is at __purge_vmap_area_lazy+0x144/0x150
   EAX: ee8a8818 EBX: c08e77d4 ECX: e7c7ae40 EDX: c08e77ec
   ESI: 000081fe EDI: e7c7ae60 EBP: e7c7ae64 ESP: e7c7ae3c
   DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
   Call Trace:
   [<c0482ad9>] free_unmap_vmap_area_noflush+0x69/0x70
   [<c0482b02>] remove_vm_area+0x22/0x70
   [<c0482c15>] __vunmap+0x45/0xe0
   [<c04831ec>] vmalloc+0x2c/0x30
   Code: 8d 59 e0 eb 04 66 90 89 cb 89 d0 e8 87 fe ff ff 8b 43 20 89 da 8d 48 e0 8d 43 20 3b 04 24 75 e7 fe 05 a8 a5 a3 c0 e9 78 ff ff ff <0f> 0b eb fe 90 8d b4 26 00 00 00 00 56 89 c6 b8 ac a5 a3 c0 31
   EIP: [<c04824a4>] __purge_vmap_area_lazy+0x144/0x150 SS:ESP 0068:e7c7ae3c

[ See also http://marc.info/?l=linux-kernel&m=126335856228090&w=2 ]

Signed-off-by: Yongseok Koh <yongseok.koh@samsung.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-21 07:20:06 -08:00
Jan Beulich 976d6dfbb0 vmalloc(): adjust gfp mask passed on nested vmalloc() invocation
- avoid wasting more precious resources (DMA or DMA32 pools), when
  being called through vmalloc_32{,_user}()
- explicitly allow using high memory here even if the outer allocation
  request doesn't allow it

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:13 -08:00
Linus Torvalds d0316554d3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits)
  m68k: rename global variable vmalloc_end to m68k_vmalloc_end
  percpu: add missing per_cpu_ptr_to_phys() definition for UP
  percpu: Fix kdump failure if booted with percpu_alloc=page
  percpu: make misc percpu symbols unique
  percpu: make percpu symbols in ia64 unique
  percpu: make percpu symbols in powerpc unique
  percpu: make percpu symbols in x86 unique
  percpu: make percpu symbols in xen unique
  percpu: make percpu symbols in cpufreq unique
  percpu: make percpu symbols in oprofile unique
  percpu: make percpu symbols in tracer unique
  percpu: make percpu symbols under kernel/ and mm/ unique
  percpu: remove some sparse warnings
  percpu: make alloc_percpu() handle array types
  vmalloc: fix use of non-existent percpu variable in put_cpu_var()
  this_cpu: Use this_cpu_xx in trace_functions_graph.c
  this_cpu: Use this_cpu_xx for ftrace
  this_cpu: Use this_cpu_xx in nmi handling
  this_cpu: Use this_cpu operations in RCU
  this_cpu: Use this_cpu ops for VM statistics
  ...

Fix up trivial (famous last words) global per-cpu naming conflicts in
	arch/x86/kvm/svm.c
	mm/slab.c
2009-12-14 09:58:24 -08:00
Tejun Heo 3f04ba8595 vmalloc: fix use of non-existent percpu variable in put_cpu_var()
vmalloc used non-existent percpu variable vmap_cpu_blocks instead of
the intended vmap_block_queue.  This went unnoticed because
put_cpu_var() didn't evaluate the parameter.  Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@suse.de>
2009-10-29 22:34:12 +09:00
Alexey Dobriyan d43c36dc6b headers: remove sched.h from interrupt.h
After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-10-11 11:20:58 -07:00
Linus Torvalds b924f9599d Merge branch 'sparc-perf-events-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sparc-perf-events-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  mm, perf_event: Make vmalloc_user() align base kernel virtual address to SHMLBA
  perf_event: Provide vmalloc() based mmap() backing
2009-10-08 12:05:50 -07:00
David Miller 2dca6999ee mm, perf_event: Make vmalloc_user() align base kernel virtual address to SHMLBA
When a vmalloc'd area is mmap'd into userspace, some kind of
co-ordination is necessary for this to work on platforms with cpu
D-caches which can have aliases.

Otherwise kernel side writes won't be seen properly in userspace
and vice versa.

If the kernel side mapping and the user side one have the same
alignment, modulo SHMLBA, this can work as long as VM_SHARED is
shared of VMA and for all current users this is true.  VM_SHARED
will force SHMLBA alignment of the user side mmap on platforms with
D-cache aliasing matters.

The bulk of this patch is just making it so that a specific
alignment can be passed down into __get_vm_area_node().  All
existing callers pass in '1' which preserves existing behavior.
vmalloc_user() gives SHMLBA for the alignment.

As a side effect this should get the video media drivers and other
vmalloc_user() users into more working shape on such systems.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <200909211922.n8LJMYjw029425@imap1.linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-08 17:02:31 +02:00
Jaswinder Singh Rajput 3700c155af mm: includecheck fix: vmalloc.c
fix the following 'make includecheck' warning:

  mm/vmalloc.c: linux/highmem.h is included more than once.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-08 07:36:38 -07:00
KAMEZAWA Hiroyuki 81ac3ad906 kcore: register module area in generic way
Some archs define MODULED_VADDR/MODULES_END which is not in VMALLOC area.
This is handled only in x86-64.  This patch make it more generic.  And we
can use vread/vwrite to access the area.  Fix it.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 07:39:42 -07:00
Jan Beulich 4481374ce8 mm: replace various uses of num_physpages by totalram_pages
Sizing of memory allocations shouldn't depend on the number of physical
pages found in a system, as that generally includes (perhaps a huge amount
of) non-RAM pages.  The amount of what actually is usable as storage
should instead be used as a basis here.

Some of the calculations (i.e.  those not intending to use high memory)
should likely even use (totalram_pages - totalhigh_pages).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:38 -07:00
KAMEZAWA Hiroyuki d0107eb073 kcore: fix vread/vwrite to be aware of holes
vread/vwrite access vmalloc area without checking there is a page or not.
In most case, this works well.

In old ages, the caller of get_vm_ara() is only IOREMAP and there is no
memory hole within vm_struct's [addr...addr + size - PAGE_SIZE] (
-PAGE_SIZE is for a guard page.)

After per-cpu-alloc patch, it uses get_vm_area() for reserve continuous
virtual address but remap _later_.  There tend to be a hole in valid
vmalloc area in vm_struct lists.  Then, skip the hole (not mapped page) is
necessary.  This patch updates vread/vwrite() for avoiding memory hole.

Routines which access vmalloc area without knowing for which addr is used
are
  - /proc/kcore
  - /dev/kmem

kcore checks IOREMAP, /dev/kmem doesn't.  After this patch, IOREMAP is
checked and /dev/kmem will avoid to read/write it.  Fixes to /proc/kcore
will be in the next patch in series.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Mike Smith <scgtrp@gmail.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:34 -07:00
KAMEZAWA Hiroyuki dd32c27998 vmalloc: unmap vmalloc area after hiding it
vmap area should be purged after vm_struct is removed from the list
because vread/vwrite etc...believes the range is valid while it's on
vm_struct list.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Mike Smith <scgtrp@gmail.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:33 -07:00
Figo.zhang bf88c8c83e vmalloc.c: fix double error checking
There is no need for double error checking.

Signed-off-by: Figo.zhang <figo1802@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:30 -07:00
Tejun Heo ca23e405e0 vmalloc: implement pcpu_get_vm_areas()
To directly use spread NUMA memories for percpu units, percpu
allocator will be updated to allow sparsely mapping units in a chunk.
As the distances between units can be very large, this makes
allocating single vmap area for each chunk undesirable.  This patch
implements pcpu_get_vm_areas() and pcpu_free_vm_areas() which
allocates and frees sparse congruent vmap areas.

pcpu_get_vm_areas() take @offsets and @sizes array which define
distances and sizes of vmap areas.  It scans down from the top of
vmalloc area looking for the top-most address which can accomodate all
the areas.  The top-down scan is to avoid interacting with regular
vmallocs which can push up these congruent areas up little by little
ending up wasting address space and page table.

To speed up top-down scan, the highest possible address hint is
maintained.  Although the scan is linear from the hint, given the
usual large holes between memory addresses between NUMA nodes, the
scanning is highly likely to finish after finding the first hole for
the last unit which is scanned first.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@suse.de>
2009-08-14 15:00:52 +09:00
Tejun Heo cf88c79006 vmalloc: separate out insert_vmalloc_vm()
Separate out insert_vmalloc_vm() from __get_vm_area_node().
insert_vmalloc_vm() initializes vm_struct from vmap_area and inserts
it into vmlist.  insert_vmalloc_vm() only initializes fields which can
be determined from @vm, @flags and @caller The rest should be
initialized by the caller.  For __get_vm_area_node(), all other fields
just need to be cleared and this is done by using kzalloc instead of
kmalloc.

This will be used to implement pcpu_get_vm_areas().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@suse.de>
2009-08-14 15:00:52 +09:00
Linus Torvalds 512626a04e Merge branch 'for-linus' of git://linux-arm.org/linux-2.6
* 'for-linus' of git://linux-arm.org/linux-2.6:
  kmemleak: Add the corresponding MAINTAINERS entry
  kmemleak: Simple testing module for kmemleak
  kmemleak: Enable the building of the memory leak detector
  kmemleak: Remove some of the kmemleak false positives
  kmemleak: Add modules support
  kmemleak: Add kmemleak_alloc callback from alloc_large_system_hash
  kmemleak: Add the vmalloc memory allocation/freeing hooks
  kmemleak: Add the slub memory allocation/freeing hooks
  kmemleak: Add the slob memory allocation/freeing hooks
  kmemleak: Add the slab memory allocation/freeing hooks
  kmemleak: Add documentation on the memory leak detector
  kmemleak: Add the base support

Manual conflict resolution (with the slab/earlyboot changes) in:
	drivers/char/vt.c
	init/main.c
	mm/slab.c
2009-06-11 14:15:57 -07:00
Pekka Enberg 43ebdac42f vmalloc: use kzalloc() instead of alloc_bootmem()
We can call vmalloc_init() after kmem_cache_init() and use kzalloc() instead of
the bootmem allocator when initializing vmalloc data structures.

Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Nick Piggin <npiggin@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2009-06-11 19:17:05 +03:00
Catalin Marinas 89219d37a2 kmemleak: Add the vmalloc memory allocation/freeing hooks
This patch adds the callbacks to kmemleak_(alloc|free) functions from
vmalloc/vfree.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-06-11 17:03:30 +01:00
Ralph Wuerthner 2498ce42d3 alloc_vmap_area: fix memory leak
If alloc_vmap_area() fails the allocated struct vmap_area has to be freed.

Signed-off-by: Ralph Wuerthner <ralphw@linux.vnet.ibm.com>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-06 16:36:10 -07:00
MinChan Kim d086817dc0 vmap: remove needless lock and list in vmap
vmap's dirty_list is unused.  It's for optimizing flushing.  but Nick
didn't write the code yet.  so, we don't need it until time as it is
needed.

This patch removes vmap_block's dirty_list and codes related to it.

Signed-off-by: MinChan Kim <minchan.kim@gmail.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01 08:59:11 -07:00
Ingo Molnar 91d75e209b Merge branch 'x86/core' into core/percpu 2009-03-04 02:29:19 +01:00
Ingo Molnar 55f2b78995 Merge branch 'x86/urgent' into x86/pat 2009-03-01 12:47:58 +01:00
Vegard Nossum cbb766766f mm: fix lazy vmap purging (use-after-free error)
I just got this new warning from kmemcheck:

    WARNING: kmemcheck: Caught 32-bit read from freed memory (c7806a60)
    a06a80c7ecde70c1a04080c700000000a06709c1000000000000000000000000
     f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f f
     ^

    Pid: 0, comm: swapper Not tainted (2.6.29-rc4 #230)
    EIP: 0060:[<c1096df7>] EFLAGS: 00000286 CPU: 0
    EIP is at __purge_vmap_area_lazy+0x117/0x140
    EAX: 00070f43 EBX: c7806a40 ECX: c1677080 EDX: 00027b66
    ESI: 00002001 EDI: c170df0c EBP: c170df00 ESP: c178830c
     DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
    CR0: 80050033 CR2: c7806b14 CR3: 01775000 CR4: 00000690
    DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
    DR6: 00004000 DR7: 00000000
     [<c1096f3e>] free_unmap_vmap_area_noflush+0x6e/0x70
     [<c1096f6a>] remove_vm_area+0x2a/0x70
     [<c1097025>] __vunmap+0x45/0xe0
     [<c10970de>] vunmap+0x1e/0x30
     [<c1008ba5>] text_poke+0x95/0x150
     [<c1008ca9>] alternatives_smp_unlock+0x49/0x60
     [<c171ef47>] alternative_instructions+0x11b/0x124
     [<c171f991>] check_bugs+0xbd/0xdc
     [<c17148c5>] start_kernel+0x2ed/0x360
     [<c171409e>] __init_begin+0x9e/0xa9
     [<ffffffff>] 0xffffffff

It happened here:

    $ addr2line -e vmlinux -i c1096df7
    mm/vmalloc.c:540

Code:

	list_for_each_entry(va, &valist, purge_list)
		__free_vmap_area(va);

It's this instruction:

    mov    0x20(%ebx),%edx

Which corresponds to a dereference of va->purge_list.next:

    (gdb) p ((struct vmap_area *) 0)->purge_list.next
    Cannot access memory at address 0x20

It seems that we should use "safe" list traversal here, as the element
is freed inside the loop. Please verify that this is the right fix.

Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-27 16:26:21 -08:00
Nick Piggin 7766970cc1 mm: vmap fix overflow
The new vmap allocator can wrap the address and get confused in the case
of large allocations or VMALLOC_END near the end of address space.

Problem reported by Christoph Hellwig on a 32-bit XFS workload.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-27 16:26:21 -08:00
Ingo Molnar ecc25fbd6b Merge branches 'x86/apic', 'x86/defconfig', 'x86/memtest', 'x86/mm' and 'linus' into x86/core 2009-02-26 06:31:32 +01:00
Peter Zijlstra 34754b69a6 x86: make vmap yell louder when it is used under irqs_disabled()
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 16:38:34 +01:00
Ingo Molnar 0edcf8d692 Merge branch 'tj-percpu' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into core/percpu
Conflicts:
	arch/x86/include/asm/pgtable.h
2009-02-24 21:52:45 +01:00
Tejun Heo c0c0a29379 vmalloc: add @align to vm_area_register_early()
Impact: allow larger alignment for early vmalloc area allocation

Some early vmalloc users might want larger alignment, for example, for
custom large page mapping.  Add @align to vm_area_register_early().
While at it, drop docbook comment on non-existent @size.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
2009-02-24 11:57:21 +09:00
Tejun Heo f6fcba7014 vmalloc: call flush_cache_vunmap() from unmap_kernel_range()
Impact: proper vcache flush on unmap_kernel_range()

flush_cache_vunmap() should be called before pages are unmapped.  Add
a call to it in unmap_kernel_range().

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Nick Piggin <npiggin@suse.de>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-20 17:57:49 -08:00
Tejun Heo 8fc4898500 vmalloc: add un/map_kernel_range_noflush()
Impact: two more public map/unmap functions

Implement map_kernel_range_noflush() and unmap_kernel_range_noflush().
These functions respectively map and unmap address range in kernel VM
area but doesn't do any vcache or tlb flushing.  These will be used by
new percpu allocator.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
2009-02-20 16:29:08 +09:00
Tejun Heo f0aa661790 vmalloc: implement vm_area_register_early()
Impact: allow multiple early vm areas

There are places where kernel VM area needs to be allocated before
vmalloc is initialized.  This is done by allocating static vm_struct,
initializing several fields and linking it to vmlist and later vmalloc
initialization picking up these from vmlist.  This is currently done
manually and if there's more than one such areas, there's no defined
way to arbitrate who gets which address.

This patch implements vm_area_register_early(), which takes vm_area
struct with flags and size initialized, assigns address to it and puts
it on the vmlist.  This way, multiple early vm areas can determine
which addresses they should use.  The only current user - alpha mm
init - is converted to use it.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-02-20 16:29:08 +09:00
Tejun Heo 734269521e vmalloc: call flush_cache_vunmap() from unmap_kernel_range()
Impact: proper vcache flush on unmap_kernel_range()

flush_cache_vunmap() should be called before pages are unmapped.  Add
a call to it in unmap_kernel_range().

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-02-20 16:29:07 +09:00
Benjamin Herrenschmidt c296861291 vmalloc: add __get_vm_area_caller()
We have get_vm_area_caller() and __get_vm_area() but not
__get_vm_area_caller()

On powerpc, I use __get_vm_area() to separate the ranges of addresses
given to vmalloc vs.  ioremap (various good reasons for that) so in order
to be able to implement the new caller tracking in /proc/vmallocinfo, I
need a "_caller" variant of it.

(akpm: needed for ongoing powerpc development, so merge it early)

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-18 15:37:53 -08:00
Andrew Morton 46666d8ac4 revert "mm: vmalloc use mutex for purge"
Revert commit e97a630eb0 ("mm: vmalloc use
mutex for purge")

Bryan Donlan reports:

: After testing 2.6.29-rc1 on xen-x86 with a btrfs root filesystem, I
: got the OOPS quoted below and a hard freeze shortly after boot.
: Boot messages and config are attached.
:
: ------------[ cut here ]------------
: Kernel BUG at c05ef80d [verbose debug info unavailable]
: invalid opcode: 0000 [#1] SMP
: last sysfs file: /sys/block/xvdc/size
: Modules linked in:
:
: Pid: 0, comm: swapper Not tainted (2.6.29-rc1 #6)
: EIP: 0061:[<c05ef80d>] EFLAGS: 00010087 CPU: 2
: EIP is at schedule+0x7cd/0x950
: EAX: d5aeca80 EBX: 00000002 ECX: 00000000 EDX: d4cb9a40
: ESI: c12f5600 EDI: d4cb9a40 EBP: d6033fa4 ESP: d6033ef4
:  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0069
: Process swapper (pid: 0, ti=d6032000 task=d6020b70 task.ti=d6032000)
: Stack:
:  000d85bc 00000000 000186a0 00000000 0dd11410 c0105417 c12efe00 0dc367c3
:  00000011 c0105d46 d5a5d310 deadbeef d4cb9a40 c07cc600 c05f1340 c12e0060
:  deadbeef d6020b70 d6020d08 00000002 c014377d 00000000 c12f5600 00002c22
: Call Trace:
:  [<c0105417>] xen_force_evtchn_callback+0x17/0x30
:  [<c0105d46>] check_events+0x8/0x12
:  [<c05f1340>] _spin_unlock_irqrestore+0x20/0x40
:  [<c014377d>] hrtimer_start_range_ns+0x12d/0x2e0
:  [<c014c4f6>] tick_nohz_restart_sched_tick+0x146/0x160
:  [<c0107485>] cpu_idle+0xa5/0xc0

and bisected it to this commit.

Let's remove it now while we have a think about the problem.

Reported-by: Bryan Donlan <bdonlan@gmail.com>
Tested-by: Christophe Saout <christophe@saout.de>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-15 16:39:40 -08:00
Ivan Kokshaysky 822c18f2e3 alpha: fix vmalloc breakage
On alpha, we have to map some stuff in the VMALLOC space very early in the
boot process (to make SRM console callbacks work and so on, see
arch/alpha/mm/init.c).  For old VM allocator, we just manually placed a
vm_struct onto the global vmlist and this worked for ages.

Unfortunately, the new allocator isn't aware of this, so it constantly
tries to allocate the VM space which is already in use, making vmalloc on
alpha defunct.

This patch forces KVA to import vmlist entries on init.

[akpm@linux-foundation.org: remove unneeded check (per Johannes)]
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-15 16:39:35 -08:00
Nick Piggin cd52858c73 mm: vmalloc make lazy unmapping configurable
Lazy unmapping in the vmalloc code has now opened the possibility for use
after free bugs to go undetected.  We can catch those by forcing an unmap
and flush (which is going to be slow, but that's what happens).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:01 -08:00
Nick Piggin e97a630eb0 mm: vmalloc use mutex for purge
The vmalloc purge lock can be a mutex so we can sleep while a purge is
going on (purge involves a global kernel TLB invalidate, so it can take
quite a while).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:01 -08:00
Glauber Costa 8487784833 mm: vmalloc improve vmallocinfo
If we do that, output of files like /proc/vmallocinfo will show things
like "vmalloc_32", "vmalloc_user", or whomever the caller was as the
caller.  This info is not as useful as the real caller of the allocation.

So, proposal is to call __vmalloc_node node directly, with matching
parameters to save the caller information

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:01 -08:00
Glauber Costa c1279c4ef3 mm: vmalloc tweak failure printk
If we can't service a vmalloc allocation, show size of the allocation that
actually failed.  Useful for debugging.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:01 -08:00
Adam Lackorzynski 2e4e27c7d0 vmalloc.c: fix flushing in vmap_page_range()
The flush_cache_vmap in vmap_page_range() is called with the end of the
range twice.  The following patch fixes this for me.

Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-04 13:33:20 -08:00
Hugh Dickins 9c24624727 KSYM_SYMBOL_LEN fixes
Miles Lane tailing /sys files hit a BUG which Pekka Enberg has tracked
to my 966c8c12dc sprint_symbol(): use
less stack exposing a bug in slub's list_locations() -
kallsyms_lookup() writes a 0 to namebuf[KSYM_NAME_LEN-1], but that was
beyond the end of page provided.

The 100 slop which list_locations() allows at end of page looks roughly
enough for all the other stuff it might print after the symbol before
it checks again: break out KSYM_SYMBOL_LEN earlier than before.

Latencytop and ftrace and are using KSYM_NAME_LEN buffers where they
need KSYM_SYMBOL_LEN buffers, and vmallocinfo a 2*KSYM_NAME_LEN buffer
where it wants a KSYM_SYMBOL_LEN buffer: fix those before anyone copies
them.

[akpm@linux-foundation.org: ftrace.h needs module.h]
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc Miles Lane <miles.lane@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:54 -08:00
Nick Piggin b29acbdcf8 mm: vmalloc fix lazy unmapping cache aliasing
Jim Radford has reported that the vmap subsystem rewrite was sometimes
causing his VIVT ARM system to behave strangely (seemed like going into
infinite loops trying to fault in pages to userspace).

We determined that the problem was most likely due to a cache aliasing
issue.  flush_cache_vunmap was only being called at the moment the page
tables were to be taken down, however with lazy unmapping, this can happen
after the page has subsequently been freed and allocated for something
else.  The dangling alias may still have dirty data attached to it.

The fix for this problem is to do the cache flushing when the caller has
called vunmap -- it would be a bug for them to write anything else to the
mapping at that point.

That appeared to solve Jim's problems.

Reported-by: Jim Radford <radford@blackbean.org>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-01 19:55:23 -08:00
Glauber Costa 0ae15132a4 mm: vmalloc search restart fix
Current vmalloc restart search for a free area in case we can't find one.
The reason is there are areas which are lazily freed, and could be
possibly freed now.  However, current implementation start searching the
tree from the last failing address, which is pretty much by definition at
the end of address space.  So, we fail.

The proposal of this patch is to restart the search from the beginning of
the requested vstart address.  This fixes the regression in running KVM
virtual machines for me, described in http://lkml.org/lkml/2008/10/28/349,
caused by commit db64fe0225.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-19 18:49:58 -08:00
Nick Piggin 496850e5f5 mm: vmalloc failure flush fix
An initial vmalloc failure should start off a synchronous flush of lazy
areas, in case someone is in progress flushing them already, which could
cause us to return an allocation failure even if there is plenty of KVA
free.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-19 18:49:58 -08:00
Nick Piggin f011c2dae6 mm: vmalloc allocator off by one
Fix off by one bug in the KVA allocator that can leave gaps in the address
space.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-19 18:49:58 -08:00
Jeremy Fitzhardinge 9b46333406 vmap: cope with vm_unmap_aliases before vmalloc_init()
Xen can end up calling vm_unmap_aliases() before vmalloc_init() has
been called.  In this case its safe to make it a simple no-op.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Linux Memory Management List <linux-mm@kvack.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-07 10:05:59 +01:00
Russell King ab4f2ee130 [ARM] fix naming of MODULE_START / MODULE_END
As of 73bdf0a60e, the kernel needs
to know where modules are located in the virtual address space.
On ARM, we located this region between MODULE_START and MODULE_END.
Unfortunately, everyone else calls it MODULES_VADDR and MODULES_END.
Update ARM to use the same naming, so is_vmalloc_or_module_addr()
can work properly.  Also update the comment on mm/vmalloc.c to
reflect that ARM also places modules in a separate region from the
vmalloc space.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-11-06 17:13:47 +00:00
Randy Dunlap e99c97ade5 mm: fix kernel-doc function notation
Delete excess kernel-doc notation in mm/ subdirectory.
Actually this is a kernel-doc notation fix.

Warning(/var/linsrc/linux-2.6.27-git10//mm/vmalloc.c:902): Excess function parameter or struct member 'returns' description in 'vm_map_ram'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-30 11:38:46 -07:00
Alexey Dobriyan 5f6a6a9c4e proc: move /proc/vmallocinfo to mm/vmalloc.c
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
2008-10-23 15:48:28 +04:00
Huang Weiyi a50c22eed5 mm: remove duplicated #include's
Removed duplicated #include <linux/vmalloc.h> in mm/vmalloc.c and
"internal.h" in mm/memory.c.

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 16:17:42 -07:00
Linus Torvalds b9d7ccf56b Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86 ACPI: fix breakage of resume on 64-bit UP systems with SMP kernel
  Introduce is_vmalloc_or_module_addr() and use with DEBUG_VIRTUAL
2008-10-20 13:27:05 -07:00
Nick Piggin db64fe0225 mm: rewrite vmap layer
Rewrite the vmap allocator to use rbtrees and lazy tlb flushing, and
provide a fast, scalable percpu frontend for small vmaps (requires a
slightly different API, though).

The biggest problem with vmap is actually vunmap.  Presently this requires
a global kernel TLB flush, which on most architectures is a broadcast IPI
to all CPUs to flush the cache.  This is all done under a global lock.  As
the number of CPUs increases, so will the number of vunmaps a scaled
workload will want to perform, and so will the cost of a global TLB flush.
 This gives terrible quadratic scalability characteristics.

Another problem is that the entire vmap subsystem works under a single
lock.  It is a rwlock, but it is actually taken for write in all the fast
paths, and the read locking would likely never be run concurrently anyway,
so it's just pointless.

This is a rewrite of vmap subsystem to solve those problems.  The existing
vmalloc API is implemented on top of the rewritten subsystem.

The TLB flushing problem is solved by using lazy TLB unmapping.  vmap
addresses do not have to be flushed immediately when they are vunmapped,
because the kernel will not reuse them again (would be a use-after-free)
until they are reallocated.  So the addresses aren't allocated again until
a subsequent TLB flush.  A single TLB flush then can flush multiple
vunmaps from each CPU.

XEN and PAT and such do not like deferred TLB flushing because they can't
always handle multiple aliasing virtual addresses to a physical address.
They now call vm_unmap_aliases() in order to flush any deferred mappings.
That call is very expensive (well, actually not a lot more expensive than
a single vunmap under the old scheme), however it should be OK if not
called too often.

The virtual memory extent information is stored in an rbtree rather than a
linked list to improve the algorithmic scalability.

There is a per-CPU allocator for small vmaps, which amortizes or avoids
global locking.

To use the per-CPU interface, the vm_map_ram / vm_unmap_ram interfaces
must be used in place of vmap and vunmap.  Vmalloc does not use these
interfaces at the moment, so it will not be quite so scalable (although it
will use lazy TLB flushing).

As a quick test of performance, I ran a test that loops in the kernel,
linearly mapping then touching then unmapping 4 pages.  Different numbers
of tests were run in parallel on an 4 core, 2 socket opteron.  Results are
in nanoseconds per map+touch+unmap.

threads           vanilla         vmap rewrite
1                 14700           2900
2                 33600           3000
4                 49500           2800
8                 70631           2900

So with a 8 cores, the rewritten version is already 25x faster.

In a slightly more realistic test (although with an older and less
scalable version of the patch), I ripped the not-very-good vunmap batching
code out of XFS, and implemented the large buffer mapping with vm_map_ram
and vm_unmap_ram...  along with a couple of other tricks, I was able to
speed up a large directory workload by 20x on a 64 CPU system.  I believe
vmap/vunmap is actually sped up a lot more than 20x on such a system, but
I'm running into other locks now.  vmap is pretty well blown off the
profiles.

Before:
1352059 total                                      0.1401
798784 _write_lock                              8320.6667 <- vmlist_lock
529313 default_idle                             1181.5022
 15242 smp_call_function                         15.8771  <- vmap tlb flushing
  2472 __get_vm_area_node                         1.9312  <- vmap
  1762 remove_vm_area                             4.5885  <- vunmap
   316 map_vm_area                                0.2297  <- vmap
   312 kfree                                      0.1950
   300 _spin_lock                                 3.1250
   252 sn_send_IPI_phys                           0.4375  <- tlb flushing
   238 vmap                                       0.8264  <- vmap
   216 find_lock_page                             0.5192
   196 find_next_bit                              0.3603
   136 sn2_send_IPI                               0.2024
   130 pio_phys_write_mmr                         2.0312
   118 unmap_kernel_range                         0.1229

After:
 78406 total                                      0.0081
 40053 default_idle                              89.4040
 33576 ia64_spinlock_contention                 349.7500
  1650 _spin_lock                                17.1875
   319 __reg_op                                   0.5538
   281 _atomic_dec_and_lock                       1.0977
   153 mutex_unlock                               1.5938
   123 iget_locked                                0.1671
   117 xfs_dir_lookup                             0.1662
   117 dput                                       0.1406
   114 xfs_iget_core                              0.0268
    92 xfs_da_hashname                            0.1917
    75 d_alloc                                    0.0670
    68 vmap_page_range                            0.0462 <- vmap
    58 kmem_cache_alloc                           0.0604
    57 memset                                     0.0540
    52 rb_next                                    0.1625
    50 __copy_user                                0.0208
    49 bitmap_find_free_region                    0.2188 <- vmap
    46 ia64_sn_udelay                             0.1106
    45 find_inode_fast                            0.1406
    42 memcmp                                     0.2188
    42 finish_task_switch                         0.1094
    42 __d_lookup                                 0.0410
    40 radix_tree_lookup_slot                     0.1250
    37 _spin_unlock_irqrestore                    0.3854
    36 xfs_bmapi                                  0.0050
    36 kmem_cache_free                            0.0256
    35 xfs_vn_getattr                             0.0322
    34 radix_tree_lookup                          0.1062
    33 __link_path_walk                           0.0035
    31 xfs_da_do_buf                              0.0091
    30 _xfs_buf_find                              0.0204
    28 find_get_page                              0.0875
    27 xfs_iread                                  0.0241
    27 __strncpy_from_user                        0.2812
    26 _xfs_buf_initialize                        0.0406
    24 _xfs_buf_lookup_pages                      0.0179
    24 vunmap_page_range                          0.0250 <- vunmap
    23 find_lock_page                             0.0799
    22 vm_map_ram                                 0.0087 <- vmap
    20 kfree                                      0.0125
    19 put_page                                   0.0330
    18 __kmalloc                                  0.0176
    17 xfs_da_node_lookup_int                     0.0086
    17 _read_lock                                 0.0885
    17 page_waitqueue                             0.0664

vmap has gone from being the top 5 on the profiles and flushing the crap
out of all TLBs, to using less than 1% of kernel time.

[akpm@linux-foundation.org: cleanups, section fix]
[akpm@linux-foundation.org: fix build on alpha]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:32 -07:00
Linus Torvalds 73bdf0a60e Introduce is_vmalloc_or_module_addr() and use with DEBUG_VIRTUAL
Impact: crash on module insertion with CONFIG_DEBUG_VIRTUAL

We would incorrectly BUG due to:

   VIRTUAL_BUG_ON(!is_vmalloc_addr(vmalloc_addr) &&
   	          !is_module_address(addr));

... because, at least on x86-64, is_module_address() doesn't do what
it should.  This patch introduces is_vmalloc_or_module_addr(), which
is what we really want anyway, and uses it instead.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-16 03:25:58 -07:00
Ingo Molnar 8daf14cf56 Merge branches 'x86/xen', 'x86/build', 'x86/microcode', 'x86/mm-debug-v2', 'x86/memory-corruption-check', 'x86/early-printk', 'x86/xsave', 'x86/ptrace-v2', 'x86/quirks', 'x86/setup', 'x86/spinlocks' and 'x86/signal' into x86/core-v2 2008-10-12 15:50:02 +02:00
Arjan van de Ven 4c8573e25f Use WARN() in mm/vmalloc.c
Use WARN() instead of a printk+WARN_ON() pair; this way the message becomes
part of the warning section for better reporting/collection.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:07 -07:00
Eric Dumazet a47a126ad5 vmallocinfo: add NUMA information
Christoph recently added /proc/vmallocinfo file to get information about
vmalloc allocations.

This patch adds NUMA specific information, giving number of pages
allocated on each memory node.

This should help to check that vmalloc() is able to respect NUMA policies.

Example of output on a four nodes machine (one cpu per node)

1) network hash tables are evenly spreaded on four nodes (OK) (Same
   point for inodes and dentries hash tables)

2) iptables tables (x_tables) are correctly allocated on each cpu node
   (OK).

3) sys_swapon() allocates its memory from one node only.

4) each loaded module is using memory on one node.

Sysadmins could tune their setup to change points 3) and 4) if necessary.

grep "pages="  /proc/vmallocinfo
0xffffc20000000000-0xffffc20000201000 2101248 alloc_large_system_hash+0x204/0x2c0 pages=512 vmalloc N0=128 N1=128 N2=128 N3=128
0xffffc20000201000-0xffffc20000302000 1052672 alloc_large_system_hash+0x204/0x2c0 pages=256 vmalloc N0=64 N1=64 N2=64 N3=64
0xffffc2000031a000-0xffffc2000031d000   12288 alloc_large_system_hash+0x204/0x2c0 pages=2 vmalloc N1=1 N2=1
0xffffc2000031f000-0xffffc2000032b000   49152 cramfs_uncompress_init+0x2e/0x80 pages=11 vmalloc N0=3 N1=3 N2=2 N3=3
0xffffc2000033e000-0xffffc20000341000   12288 sys_swapon+0x640/0xac0 pages=2 vmalloc N0=2
0xffffc20000341000-0xffffc20000344000   12288 xt_alloc_table_info+0xfe/0x130 [x_tables] pages=2 vmalloc N0=2
0xffffc20000344000-0xffffc20000347000   12288 xt_alloc_table_info+0xfe/0x130 [x_tables] pages=2 vmalloc N1=2
0xffffc20000347000-0xffffc2000034a000   12288 xt_alloc_table_info+0xfe/0x130 [x_tables] pages=2 vmalloc N2=2
0xffffc2000034a000-0xffffc2000034d000   12288 xt_alloc_table_info+0xfe/0x130 [x_tables] pages=2 vmalloc N3=2
0xffffc20004381000-0xffffc20004402000  528384 alloc_large_system_hash+0x204/0x2c0 pages=128 vmalloc N0=32 N1=32 N2=32 N3=32
0xffffc20004402000-0xffffc20004803000 4198400 alloc_large_system_hash+0x204/0x2c0 pages=1024 vmalloc vpages N0=256 N1=256 N2=256 N3=256
0xffffc20004803000-0xffffc20004904000 1052672 alloc_large_system_hash+0x204/0x2c0 pages=256 vmalloc N0=64 N1=64 N2=64 N3=64
0xffffc20004904000-0xffffc20004bec000 3047424 sys_swapon+0x640/0xac0 pages=743 vmalloc vpages N0=743
0xffffffffa0000000-0xffffffffa000f000   61440 sys_init_module+0xc27/0x1d00 pages=14 vmalloc N1=14
0xffffffffa000f000-0xffffffffa0014000   20480 sys_init_module+0xc27/0x1d00 pages=4 vmalloc N0=4
0xffffffffa0014000-0xffffffffa0017000   12288 sys_init_module+0xc27/0x1d00 pages=2 vmalloc N0=2
0xffffffffa0017000-0xffffffffa0022000   45056 sys_init_module+0xc27/0x1d00 pages=10 vmalloc N1=10
0xffffffffa0022000-0xffffffffa0028000   24576 sys_init_module+0xc27/0x1d00 pages=5 vmalloc N3=5
0xffffffffa0028000-0xffffffffa0050000  163840 sys_init_module+0xc27/0x1d00 pages=39 vmalloc N1=39
0xffffffffa0050000-0xffffffffa0052000    8192 sys_init_module+0xc27/0x1d00 pages=1 vmalloc N1=1
0xffffffffa0052000-0xffffffffa0056000   16384 sys_init_module+0xc27/0x1d00 pages=3 vmalloc N1=3
0xffffffffa0056000-0xffffffffa0081000  176128 sys_init_module+0xc27/0x1d00 pages=42 vmalloc N3=42
0xffffffffa0081000-0xffffffffa00ae000  184320 sys_init_module+0xc27/0x1d00 pages=44 vmalloc N3=44
0xffffffffa00ae000-0xffffffffa00b1000   12288 sys_init_module+0xc27/0x1d00 pages=2 vmalloc N3=2
0xffffffffa00b1000-0xffffffffa00b9000   32768 sys_init_module+0xc27/0x1d00 pages=7 vmalloc N0=7
0xffffffffa00b9000-0xffffffffa00c4000   45056 sys_init_module+0xc27/0x1d00 pages=10 vmalloc N3=10
0xffffffffa00c6000-0xffffffffa00e0000  106496 sys_init_module+0xc27/0x1d00 pages=25 vmalloc N2=25
0xffffffffa00e0000-0xffffffffa00f1000   69632 sys_init_module+0xc27/0x1d00 pages=16 vmalloc N2=16
0xffffffffa00f1000-0xffffffffa00f4000   12288 sys_init_module+0xc27/0x1d00 pages=2 vmalloc N3=2
0xffffffffa00f4000-0xffffffffa00f7000   12288 sys_init_module+0xc27/0x1d00 pages=2 vmalloc N3=2

[akpm@linux-foundation.org: fix comment]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:17 -07:00
Ingo Molnar 7aa413def7 x86, MM: virtual address debug, cleanups
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-19 13:33:11 +02:00
Jiri Slaby 59ea746337 MM: virtual address debug
Add some (configurable) expensive sanity checking to catch wrong address
translations on x86.

- create linux/mmdebug.h file to be able include this file in
  asm headers to not get unsolvable loops in header files
- __phys_addr on x86_32 became a function in ioremap.c since
  PAGE_OFFSET, is_vmalloc_addr and VMALLOC_* non-constasts are undefined
  if declared in page_32.h
- add __phys_addr_const for initializing doublefault_tss.__cr3

Tested on 386, 386pae, x86_64 and x86_64 numa=fake=2.

Contains Andi's enable numa virtual address debug patch.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-19 13:31:42 +02:00
Randy Dunlap c85d194bfd docbook: fix vmalloc missing parameter notation
Fix vmalloc kernel-doc warning:

Warning(linux-2.6.25-git14//mm/vmalloc.c:555): No description found for parameter 'caller'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-01 08:03:59 -07:00
Thomas Gleixner 3ac7fe5a4a infrastructure to debug (dynamic) objects
We can see an ever repeating problem pattern with objects of any kind in the
kernel:

1) freeing of active objects
2) reinitialization of active objects

Both problems can be hard to debug because the crash happens at a point where
we have no chance to decode the root cause anymore.  One problem spot are
kernel timers, where the detection of the problem often happens in interrupt
context and usually causes the machine to panic.

While working on a timer related bug report I had to hack specialized code
into the timer subsystem to get a reasonable hint for the root cause.  This
debug hack was fine for temporary use, but far from a mergeable solution due
to the intrusiveness into the timer code.

The code further lacked the ability to detect and report the root cause
instantly and keep the system operational.

Keeping the system operational is important to get hold of the debug
information without special debugging aids like serial consoles and special
knowledge of the bug reporter.

The problems described above are not restricted to timers, but timers tend to
expose it usually in a full system crash.  Other objects are less explosive,
but the symptoms caused by such mistakes can be even harder to debug.

Instead of creating specialized debugging code for the timer subsystem a
generic infrastructure is created which allows developers to verify their code
and provides an easy to enable debug facility for users in case of trouble.

The debugobjects core code keeps track of operations on static and dynamic
objects by inserting them into a hashed list and sanity checking them on
object operations and provides additional checks whenever kernel memory is
freed.

The tracked object operations are:
- initializing an object
- adding an object to a subsystem list
- deleting an object from a subsystem list

Each operation is sanity checked before the operation is executed and the
subsystem specific code can provide a fixup function which allows to prevent
the damage of the operation.  When the sanity check triggers a warning message
and a stack trace is printed.

The list of operations can be extended if the need arises.  For now it's
limited to the requirements of the first user (timers).

The core code enqueues the objects into hash buckets.  The hash index is
generated from the address of the object to simplify the lookup for the check
on kfree/vfree.  Each bucket has it's own spinlock to avoid contention on a
global lock.

The debug code can be compiled in without being active.  The runtime overhead
is minimal and could be optimized by asm alternatives.  A kernel command line
option enables the debugging code.

Thanks to Ingo Molnar for review, suggestions and cleanup patches.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:53 -07:00
Christoph Lameter 2301696932 vmallocinfo: add caller information
Add caller information so that /proc/vmallocinfo shows where the allocation
request for a slice of vmalloc memory originated.

Results in output like this:

0xffffc20000000000-0xffffc20000801000 8392704 alloc_large_system_hash+0x127/0x246 pages=2048 vmalloc vpages
0xffffc20000801000-0xffffc20000806000   20480 alloc_large_system_hash+0x127/0x246 pages=4 vmalloc
0xffffc20000806000-0xffffc20000c07000 4198400 alloc_large_system_hash+0x127/0x246 pages=1024 vmalloc vpages
0xffffc20000c07000-0xffffc20000c0a000   12288 alloc_large_system_hash+0x127/0x246 pages=2 vmalloc
0xffffc20000c0a000-0xffffc20000c0c000    8192 acpi_os_map_memory+0x13/0x1c phys=cff68000 ioremap
0xffffc20000c0c000-0xffffc20000c0f000   12288 acpi_os_map_memory+0x13/0x1c phys=cff64000 ioremap
0xffffc20000c10000-0xffffc20000c15000   20480 acpi_os_map_memory+0x13/0x1c phys=cff65000 ioremap
0xffffc20000c16000-0xffffc20000c18000    8192 acpi_os_map_memory+0x13/0x1c phys=cff69000 ioremap
0xffffc20000c18000-0xffffc20000c1a000    8192 acpi_os_map_memory+0x13/0x1c phys=fed1f000 ioremap
0xffffc20000c1a000-0xffffc20000c1c000    8192 acpi_os_map_memory+0x13/0x1c phys=cff68000 ioremap
0xffffc20000c1c000-0xffffc20000c1e000    8192 acpi_os_map_memory+0x13/0x1c phys=cff68000 ioremap
0xffffc20000c1e000-0xffffc20000c20000    8192 acpi_os_map_memory+0x13/0x1c phys=cff68000 ioremap
0xffffc20000c20000-0xffffc20000c22000    8192 acpi_os_map_memory+0x13/0x1c phys=cff68000 ioremap
0xffffc20000c22000-0xffffc20000c24000    8192 acpi_os_map_memory+0x13/0x1c phys=cff68000 ioremap
0xffffc20000c24000-0xffffc20000c26000    8192 acpi_os_map_memory+0x13/0x1c phys=e0081000 ioremap
0xffffc20000c26000-0xffffc20000c28000    8192 acpi_os_map_memory+0x13/0x1c phys=e0080000 ioremap
0xffffc20000c28000-0xffffc20000c2d000   20480 alloc_large_system_hash+0x127/0x246 pages=4 vmalloc
0xffffc20000c2d000-0xffffc20000c31000   16384 tcp_init+0xd5/0x31c pages=3 vmalloc
0xffffc20000c31000-0xffffc20000c34000   12288 alloc_large_system_hash+0x127/0x246 pages=2 vmalloc
0xffffc20000c34000-0xffffc20000c36000    8192 init_vdso_vars+0xde/0x1f1
0xffffc20000c36000-0xffffc20000c38000    8192 pci_iomap+0x8a/0xb4 phys=d8e00000 ioremap
0xffffc20000c38000-0xffffc20000c3a000    8192 usb_hcd_pci_probe+0x139/0x295 [usbcore] phys=d8e00000 ioremap
0xffffc20000c3a000-0xffffc20000c3e000   16384 sys_swapon+0x509/0xa15 pages=3 vmalloc
0xffffc20000c40000-0xffffc20000c61000  135168 e1000_probe+0x1c4/0xa32 phys=d8a20000 ioremap
0xffffc20000c61000-0xffffc20000c6a000   36864 _xfs_buf_map_pages+0x8e/0xc0 vmap
0xffffc20000c6a000-0xffffc20000c73000   36864 _xfs_buf_map_pages+0x8e/0xc0 vmap
0xffffc20000c73000-0xffffc20000c7c000   36864 _xfs_buf_map_pages+0x8e/0xc0 vmap
0xffffc20000c7c000-0xffffc20000c7f000   12288 e1000e_setup_tx_resources+0x29/0xbe pages=2 vmalloc
0xffffc20000c80000-0xffffc20001481000 8392704 pci_mmcfg_arch_init+0x90/0x118 phys=e0000000 ioremap
0xffffc20001481000-0xffffc20001682000 2101248 alloc_large_system_hash+0x127/0x246 pages=512 vmalloc
0xffffc20001682000-0xffffc20001e83000 8392704 alloc_large_system_hash+0x127/0x246 pages=2048 vmalloc vpages
0xffffc20001e83000-0xffffc20002204000 3674112 alloc_large_system_hash+0x127/0x246 pages=896 vmalloc vpages
0xffffc20002204000-0xffffc2000220d000   36864 _xfs_buf_map_pages+0x8e/0xc0 vmap
0xffffc2000220d000-0xffffc20002216000   36864 _xfs_buf_map_pages+0x8e/0xc0 vmap
0xffffc20002216000-0xffffc2000221f000   36864 _xfs_buf_map_pages+0x8e/0xc0 vmap
0xffffc2000221f000-0xffffc20002228000   36864 _xfs_buf_map_pages+0x8e/0xc0 vmap
0xffffc20002228000-0xffffc20002231000   36864 _xfs_buf_map_pages+0x8e/0xc0 vmap
0xffffc20002231000-0xffffc20002234000   12288 e1000e_setup_rx_resources+0x35/0x122 pages=2 vmalloc
0xffffc20002240000-0xffffc20002261000  135168 e1000_probe+0x1c4/0xa32 phys=d8a60000 ioremap
0xffffc20002261000-0xffffc2000270c000 4894720 sys_swapon+0x509/0xa15 pages=1194 vmalloc vpages
0xffffffffa0000000-0xffffffffa0022000  139264 module_alloc+0x4f/0x55 pages=33 vmalloc
0xffffffffa0022000-0xffffffffa0029000   28672 module_alloc+0x4f/0x55 pages=6 vmalloc
0xffffffffa002b000-0xffffffffa0034000   36864 module_alloc+0x4f/0x55 pages=8 vmalloc
0xffffffffa0034000-0xffffffffa003d000   36864 module_alloc+0x4f/0x55 pages=8 vmalloc
0xffffffffa003d000-0xffffffffa0049000   49152 module_alloc+0x4f/0x55 pages=11 vmalloc
0xffffffffa0049000-0xffffffffa0050000   28672 module_alloc+0x4f/0x55 pages=6 vmalloc

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:21 -07:00
Christoph Lameter a10aa57987 vmalloc: show vmalloced areas via /proc/vmallocinfo
Implement a new proc file that allows the display of the currently allocated
vmalloc memory.

It allows to see the users of vmalloc.  That is important if vmalloc space is
scarce (i386 for example).

And it's going to be important for the compound page fallback to vmalloc.
Many of the current users can be switched to use compound pages with fallback.
 This means that the number of users of vmalloc is reduced and page tables no
longer necessary to access the memory.  /proc/vmallocinfo allows to review how
that reduction occurs.

If memory becomes fragmented and larger order allocations are no longer
possible then /proc/vmallocinfo allows to see which compound page allocations
fell back to virtual compound pages.  That is important for new users of
virtual compound pages.  Such as order 1 stack allocation etc that may
fallback to virtual compound pages in the future.

/proc/vmallocinfo permissions are made readable-only-by-root to avoid possible
information leakage.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: CONFIG_MMU=n build fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:21 -07:00
Randy Dunlap 7682486b3e mm: fix various kernel-doc comments
Fix various kernel-doc notation in mm/:

filemap.c: add function short description; convert 2 to kernel-doc
fremap.c: change parameter 'prot' to @prot
pagewalk.c: change "-" in function parameters to ":"
slab.c: fix short description of kmem_ptr_validate()
swap.c: fix description & parameters of put_pages_list()
swap_state.c: fix function parameters
vmalloc.c: change "@returns" to "Returns:" since that is not a parameter

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-19 18:53:35 -07:00
Martin Schwidefsky 2f569afd9c CONFIG_HIGHPTE vs. sub-page page tables.
Background: I've implemented 1K/2K page tables for s390.  These sub-page
page tables are required to properly support the s390 virtualization
instruction with KVM.  The SIE instruction requires that the page tables
have 256 page table entries (pte) followed by 256 page status table entries
(pgste).  The pgstes are only required if the process is using the SIE
instruction.  The pgstes are updated by the hardware and by the hypervisor
for a number of reasons, one of them is dirty and reference bit tracking.
To avoid wasting memory the standard pte table allocation should return
1K/2K (31/64 bit) and 2K/4K if the process is using SIE.

Problem: Page size on s390 is 4K, page table size is 1K or 2K.  That means
the s390 version for pte_alloc_one cannot return a pointer to a struct
page.  Trouble is that with the CONFIG_HIGHPTE feature on x86 pte_alloc_one
cannot return a pointer to a pte either, since that would require more than
32 bit for the return value of pte_alloc_one (and the pte * would not be
accessible since its not kmapped).

Solution: The only solution I found to this dilemma is a new typedef: a
pgtable_t.  For s390 pgtable_t will be a (pte *) - to be introduced with a
later patch.  For everybody else it will be a (struct page *).  The
additional problem with the initialization of the ptl lock and the
NR_PAGETABLE accounting is solved with a constructor pgtable_page_ctor and
a destructor pgtable_page_dtor.  The page table allocation and free
functions need to call these two whenever a page table page is allocated or
freed.  pmd_populate will get a pgtable_t instead of a struct page pointer.
 To get the pgtable_t back from a pmd entry that has been installed with
pmd_populate a new function pmd_pgtable is added.  It replaces the pmd_page
call in free_pte_range and apply_to_pte_range.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:42 -08:00
Robert Bragg 5dc3318528 mm: don't allow ioremapping of ranges larger than vmalloc space
When running with a 16M IOREMAP_MAX_ORDER (on armv7) we found that the
vmlist search routine in __get_vm_area_node can mistakenly allow a driver
to ioremap a range larger than vmalloc space.

If at the time of the ioremap all existing vmlist areas sit below the
determined alignment then the search routine continues past all entries and
exits the for loop - straight into the found: label - without ever testing
for integer wrapping or that the requested size fits.

We were seeing a driver successfully ioremap 128M of flash even though
there was only 120M of vmalloc space.  From that point the system was left
with the remainder of the first 16M of space to vmalloc/ioremap within.

Signed-off-by: Robert Bragg <robert@sixbynine.org>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:18 -08:00
Adrian Bunk e31d9eb5c1 make __vmalloc_area_node() static
__vmalloc_area_node() can become static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:17 -08:00
Christoph Lameter bf53d6f8fa vmalloc: clean up page array indexing
The page array is repeatedly indexed both in vunmap and vmalloc_area_node().
Add a temporary variable to make it easier to read (and easier to patch
later).

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:14 -08:00
Christoph Lameter b3bdda02aa vmalloc: add const to void* parameters
Make vmalloc functions work the same way as kfree() and friends that
take a const void * argument.

[akpm@linux-foundation.org: fix consts, coding-style]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:14 -08:00
Christoph Lameter 48667e7a43 Move vmalloc_to_page() to mm/vmalloc.
We already have page table manipulation for vmalloc in vmalloc.c. Move the
vmalloc_to_page() function there as well.

Move the definitions for vmalloc related functions in mm.h to a newly created
section.  A better place would be vmalloc.h but mm.h is basic and may depend
on these functions.  An alternative would be to include vmalloc.h in mm.h
(like done for vmstat.h).

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:13 -08:00
Simon Arlott 183ff22bb6 spelling fixes: mm/
Spelling fixes in mm/.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 01:27:18 +02:00
Christoph Lameter 6cb062296f Categorize GFP flags
The function of GFP_LEVEL_MASK seems to be unclear.  In order to clear up
the mystery we get rid of it and replace GFP_LEVEL_MASK with 3 sets of GFP
flags:

GFP_RECLAIM_MASK	Flags used to control page allocator reclaim behavior.

GFP_CONSTRAINT_MASK	Flags used to limit where allocations can occur.

GFP_SLAB_BUG_MASK	Flags that the slab allocator BUG()s on.

These replace the uses of GFP_LEVEL mask in the slab allocators and in
vmalloc.c.

The use of the flags not included in these sets may occur as a result of a
slab allocation standing in for a page allocation when constructing scatter
gather lists.  Extraneous flags are cleared and not passed through to the
page allocator.  __GFP_MOVABLE/RECLAIMABLE, __GFP_COLD and __GFP_COMP will
now be ignored if passed to a slab allocator.

Change the allocation of allocator meta data in SLAB and vmalloc to not
pass through flags listed in GFP_CONSTRAINT_MASK.  SLAB already removes the
__GFP_THISNODE flag for such allocations.  Generalize that to also cover
vmalloc.  The use of GFP_CONSTRAINT_MASK also includes __GFP_HARDWALL.

The impact of allocator metadata placement on access latency to the
cachelines of the object itself is minimal since metadata is only
referenced on alloc and free.  The attempt is still made to place the meta
data optimally but we consistently allow fallback both in SLAB and vmalloc
(SLUB does not need to allocate metadata like that).

Allocator metadata may serve multiple in kernel users and thus should not
be subject to the limitations arising from a single allocation context.

[akpm@linux-foundation.org: fix fallback_alloc()]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:42:59 -07:00
Rusty Russell 5992b6dac0 lguest: export symbols for lguest as a module
lguest does some fairly lowlevel things to support a host, which
normal modules don't need:

math_state_restore:
	When the guest triggers a Device Not Available fault, we need
	to be able to restore the FPU

__put_task_struct:
	We need to hold a reference to another task for inter-guest
	I/O, and put_task_struct() is an inline function which calls
	__put_task_struct.

access_process_vm:
	We need to access another task for inter-guest I/O.

map_vm_area & __get_vm_area:
	We need to map the switcher shim (ie. monitor) at 0xFFC01000.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:52 -07:00
Benjamin Herrenschmidt 7ac674f527 vmalloc_32 should use GFP_KERNEL
I've noticed lots of failures of vmalloc_32 on machines where it
shouldn't have failed unless it was doing an atomic operation.

Looking closely, I noticed that:

#if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
#define GFP_VMALLOC32 GFP_DMA32
#elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
#define GFP_VMALLOC32 GFP_DMA
#else
#define GFP_VMALLOC32 GFP_KERNEL
#endif

Which seems to be incorrect, it should always -or- in the DMA flags
on top of GFP_KERNEL, thus this patch.

This fixes frequent errors launchin X with the nouveau DRM for example.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:50 -07:00
Jeremy Fitzhardinge 5f4352fbff Allocate and free vmalloc areas
Allocate/release a chunk of vmalloc address space:
 alloc_vm_area reserves a chunk of address space, and makes sure all
 the pagetables are constructed for that address range - but no pages.

 free_vm_area releases the address space range.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ian Pratt <ian.pratt@xensource.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: "Jan Beulich" <JBeulich@novell.com>
Cc: "Andi Kleen" <ak@muc.de>
2007-07-18 08:47:41 -07:00
Christoph Lameter 94f6030ca7 Slab allocators: Replace explicit zeroing with __GFP_ZERO
kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing
variant in the past.  But with __GFP_ZERO it is possible now to do zeroing
while allocating.

Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever
we can.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:02 -07:00
Benjamin Herrenschmidt c19c03fc74 [POWERPC] unmap_vm_area becomes unmap_kernel_range for the public
This makes unmap_vm_area static and a wrapper around a new
exported unmap_kernel_range that takes an explicit range instead
of a vm_area struct.

This makes it more versatile for code that wants to play with kernel
page tables outside of the standard vmalloc area.

(One example is some rework of the PowerPC PCI IO space mapping
code that depends on that patch and removes some code duplication
and horrible abuse of forged struct vm_struct).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-06-14 22:29:56 +10:00
Benjamin Herrenschmidt d55e2ca873 Make __vunmap static
__vunmap doesn't seem to be used outside of mm/vmalloc.c, and has
no prototype in any header so let's make it static

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-17 05:23:04 -07:00
Christoph Hellwig 1eeb66a1bb move die notifier handling to common code
This patch moves the die notifier handling to common code.  Previous
various architectures had exactly the same code for it.  Note that the new
code is compiled unconditionally, this should be understood as an appel to
the other architecture maintainer to implement support for it aswell (aka
sprinkling a notify_die or two in the proper place)

arm had a notifiy_die that did something totally different, I renamed it to
arm_notify_die as part of the patch and made it static to the file it's
declared and used at.  avr32 used to pass slightly less information through
this interface and I brought it into line with the other architectures.

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix vmalloc_sync_all bustage]
[bryan.wu@analog.com: fix vmalloc_sync_all in nommu]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:04 -07:00
Andi Kleen 0d08e0d3a9 [PATCH] x86-64: Fix vmalloc_32 to really allocate <4GB on 64bit platforms
Ugly ifdef, but should handle all 64bit platforms that have suitable
zones. On some like Altix it's probably impossible without IOMMU
use to get memory <4GB this way,  but they have to live with that.
Signed-off-by: Andi Kleen <ak@suse.de>
2007-05-02 19:27:12 +02:00
Robert P. J. Day 72fd4a35a8 [PATCH] Numerous fixes to kernel-doc info in source files.
A variety of (mostly) innocuous fixes to the embedded kernel-doc content in
source files, including:

  * make multi-line initial descriptions single line
  * denote some function names, constants and structs as such
  * change erroneous opening '/*' to '/**' in a few places
  * reword some text for clarity

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:32 -08:00
OGAWA Hirofumi 31be830953 [PATCH] Fix strange size check in __get_vm_area_node()
Recently, __get_vm_area_node() was changed like following

 	if (unlikely(!area))
 		return NULL;

-	if (unlikely(!size)) {
-		kfree (area);
+	if (unlikely(!size))
 		return NULL;
-	}

It is leaking `area', also original code seems strange already.
Probably, we wanted to do this patch.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-16 11:43:38 -08:00
Eric Dumazet 2b4ac44e7c [PATCH] vmalloc: optimization, cleanup, bugfixes
- reorder 'struct vm_struct' to speedup lookups on CPUS with small cache
  lines.  The fields 'next,addr,size' should be now in the same cache line,
  to speedup lookups.

- One minor cleanup in __get_vm_area_node()

- Bugfixes in vmalloc_user() and vmalloc_32_user() NULL returns from
  __vmalloc() and __find_vm_area() were not tested.

[akpm@osdl.org: remove redundant BUG_ONs]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-13 07:40:42 -08:00
Giridhar Pemmasani 5211e6e6c6 [PATCH] Fix GFP_HIGHMEM slab panic
As reported by Martin J. Bligh <mbligh@google.com>, we let through some
non-slab bits to slab allocation through __get_vm_area_node when doing a
vmalloc.

I haven't been able to reproduce this, although I understand why it
happens: vmalloc allocates memory with

GFP_KERNEL | __GFP_HIGHMEM

and commit 52fd24ca1d resulted in the same
flags are passed down to cache_alloc_refill, causing the BUG.  The
following patch fixes it.

Note that when calling kmalloc_node, I am masking off __GFP_HIGHMEM with
GFP_LEVEL_MASK, whereas __vmalloc_area_node does the same with

~(__GFP_HIGHMEM | __GFP_ZERO).

IMHO, using GFP_LEVEL_MASK is preferable, but either should fix this
problem.

Signed-off-by: Giridhar Pemmasani (pgiri@yahoo.com)
Cc: Martin J. Bligh <mbligh@google.com>
Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-29 08:01:58 -08:00
Giridhar Pemmasani 52fd24ca1d [PATCH] __vmalloc with GFP_ATOMIC causes 'sleeping from invalid context'
If __vmalloc is called to allocate memory with GFP_ATOMIC in atomic
context, the chain of calls results in __get_vm_area_node allocating memory
for vm_struct with GFP_KERNEL, causing the 'sleeping from invalid context'
warning.  This patch fixes it by passing the gfp flags along so
__get_vm_area_node allocates memory for vm_struct with the same flags.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28 11:30:52 -07:00
Andrew Morton 286e1ea3ac [PATCH] vmalloc(): don't pass __GFP_ZERO to slab
A recent change to the vmalloc() code accidentally resulted in us passing
__GFP_ZERO into the slab allocator.  But we only wanted __GFP_ZERO for the
actual pages whcih are being vmalloc()ed, and passing __GFP_ZERO into slab is
not a rational thing to ask for.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17 08:18:44 -07:00
Michael Opdenacker c1c8897f83 Spelling fix: "control" instead of "cotrol"
This patch against fixes a spelling mistake ("control" instead of "cotrol").

Signed-off-by: Michael Opdenacker <michael@free-electrons.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 23:21:02 +02:00
Rolf Eike Beer d24afc57d5 [PATCH] Mark __remove_vm_area() static
The function is exported but not used from anywhere else.  It's also marked as
"not for driver use" so noone out there should really care.

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:13 -07:00
Rolf Eike Beer ead04089b1 [PATCH] Fix kerneldoc comments in mm/vmalloc.c
The empty line between the short description and the first argument
description causes a section to appear twice in the generated manpage.
Also the short description should really be short: the script can't handle
multiple lines.

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:13 -07:00
Adrian Bunk b221385bc4 [PATCH] mm/: make functions static
This patch makes the following needlessly global functions static:
 - slab.c: kmem_find_general_cachep()
 - swap.c: __page_cache_release()
 - vmalloc.c: __vmalloc_node()

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:45 -07:00
Jan Kiszka 8757d5fa6b [PATCH] mm: fix oom roll-back of __vmalloc_area_node
__vunmap must not rely on area->nr_pages when picking the release methode
for area->pages.  It may be too small when __vmalloc_area_node failed early
due to lacking memory.  Instead, use a flag in vmstruct to differentiate.

Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14 21:53:51 -07:00