Commit Graph

98 Commits

Author SHA1 Message Date
Ingo Molnar 7ae383be81 Merge branch 'linus' into x86/asm, before applying dependent patch
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08 13:33:33 +02:00
Andy Lutomirski aac82d3191 x86, paravirt, xen: Remove the 64-bit ->irq_enable_sysexit() pvop
We don't use irq_enable_sysexit on 64-bit kernels any more.
Remove all the paravirt and Xen machinery to support it on
64-bit kernels.

Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/8a03355698fe5b94194e9e7360f19f91c1b2cf1f.1428100853.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-22 08:07:45 +02:00
Kirill A. Shutemov 9823336833 x86: expose number of page table levels on Kconfig level
We would want to use number of page table level to define mm_struct.
Let's expose it as CONFIG_PGTABLE_LEVELS.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:49:02 -07:00
Masami Hiramatsu 8027197220 kprobes, x86: Prohibit probing on native_set_debugreg()/load_idt()
Since the kprobes uses do_debug for single stepping,
functions called from do_debug() before notify_die() must not
be probed.

And also native_load_idt() is called from paranoid_exit when
returning int3, this also must not be probed.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: virtualization@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/20140417081719.26341.65542.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:02:58 +02:00
Masami Hiramatsu 376e242429 kprobes: Introduce NOKPROBE_SYMBOL() macro to maintain kprobes blacklist
Introduce NOKPROBE_SYMBOL() macro which builds a kprobes
blacklist at kernel build time.

The usage of this macro is similar to EXPORT_SYMBOL(),
placed after the function definition:

  NOKPROBE_SYMBOL(function);

Since this macro will inhibit inlining of static/inline
functions, this patch also introduces a nokprobe_inline macro
for static/inline functions. In this case, we must use
NOKPROBE_SYMBOL() for the inline function caller.

When CONFIG_KPROBES=y, the macro stores the given function
address in the "_kprobe_blacklist" section.

Since the data structures are not fully initialized by the
macro (because there is no "size" information),  those
are re-initialized at boot time by using kallsyms.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/20140417081705.26341.96719.stgit@ltc230.yrl.intra.hitachi.co.jp
Cc: Alok Kataria <akataria@vmware.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christopher Li <sparse@chrisli.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jan-Simon Möller <dl9pf@gmx.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-sparse@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:02:56 +02:00
H. Peter Anvin f2a7b303d6 x86, paravirt: Remove duplicate definition for DEF_NATIVE
DEF_NATIVE() is defined in paravirt_types.h, remove duplicate
definition in paravirt.c

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Andi Kleen <ak@linux.kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/CA%2B55aFxVv==DC0JdS87V%2BcPr-twN%2BTujYg5XmgHOjJOAkZ4xwQ@mail.gmail.com
2013-09-04 09:46:43 -07:00
Andi Kleen 9a55fdbe94 x86, asmlinkage, paravirt: Add __visible/asmlinkage to xen paravirt ops
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1375740170-7446-13-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-06 14:20:56 -07:00
Linus Torvalds 1e2f5b598a Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 paravirt update from Ingo Molnar:
 "Various paravirtualization related changes - the biggest one makes
  guest support optional via CONFIG_HYPERVISOR_GUEST"

* 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, wakeup, sleep: Use pvops functions for changing GDT entries
  x86, xen, gdt: Remove the pvops variant of store_gdt.
  x86-32, gdt: Store/load GDT for ACPI S3 or hibernation/resume path is not needed
  x86-64, gdt: Store/load GDT for ACPI S3 or hibernate/resume path is not needed.
  x86: Make Linux guest support optional
  x86, Kconfig: Move PARAVIRT_DEBUG into the paravirt menu
2013-04-30 08:41:21 -07:00
Konrad Rzeszutek Wilk 357d122670 x86, xen, gdt: Remove the pvops variant of store_gdt.
The two use-cases where we needed to store the GDT were during ACPI S3 suspend
and resume. As the patches:
 x86/gdt/i386: store/load GDT for ACPI S3 or hibernation/resume path is not needed
 x86/gdt/64-bit: store/load GDT for ACPI S3 or hibernate/resume path is not needed.

have demonstrated - there are other mechanism by which the GDT is
saved and reloaded during early resume path.

Hence we do not need to worry about the pvops call-chain for saving the
GDT and can and can eliminate it. The other areas where the store_gdt is
used are never going to be hit when running under the pvops platforms.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/1365194544-14648-4-git-send-email-konrad.wilk@oracle.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-11 15:40:38 -07:00
Boris Ostrovsky 511ba86e1d x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metal
Invoking arch_flush_lazy_mmu_mode() results in calls to
preempt_enable()/disable() which may have performance impact.

Since lazy MMU is not used on bare metal we can patch away
arch_flush_lazy_mmu_mode() so that it is never called in such
environment.

[ hpa: the previous patch "Fix vmalloc_fault oops during lazy MMU
  updates" may cause a minor performance regression on
  bare metal.  This patch resolves that performance regression.  It is
  somewhat unclear to me if this is a good -stable candidate. ]

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: http://lkml.kernel.org/r/1364045796-10720-2-git-send-email-konrad.wilk@oracle.com
Tested-by: Josh Boyer <jwboyer@redhat.com>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org> SEE NOTE ABOVE
2013-04-10 11:25:10 -07:00
Andre Przywara 1f975f78c8 x86, pvops: Remove hooks for {rd,wr}msr_safe_regs
There were paravirt_ops hooks for the full register set variant of
{rd,wr}msr_safe which are actually not used by anyone anymore. Remove
them to make the code cleaner and avoid silent breakages when the pvops
members were uninitialized. This has been boot-tested natively and under
Xen with PVOPS enabled and disabled on one machine.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Link: http://lkml.kernel.org/r/1338562358-28182-2-git-send-email-bp@amd64.org
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-06-07 11:41:08 -07:00
Alex Shi c6ae41e7d4 x86: replace percpu_xxx funcs with this_cpu_xxx
Since percpu_xxx() serial functions are duplicated with this_cpu_xxx().
Removing percpu_xxx() definition and replacing them by this_cpu_xxx()
in code. There is no function change in this patch, just preparation for
later percpu_xxx serial function removing.

On x86 machine the this_cpu_xxx() serial functions are same as
__this_cpu_xxx() without no unnecessary premmpt enable/disable.

Thanks for Stephen Rothwell, he found and fixed a i386 build error in
the patch.

Also thanks for Andrew Morton, he kept updating the patchset in Linus'
tree.

Signed-off-by: Alex Shi <alex.shi@intel.com>
Acked-by: Christoph Lameter <cl@gentwo.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2012-05-14 14:15:31 -07:00
Linus Torvalds 0195c00244 Disintegrate and delete asm/system.h
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Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system

Pull "Disintegrate and delete asm/system.h" from David Howells:
 "Here are a bunch of patches to disintegrate asm/system.h into a set of
  separate bits to relieve the problem of circular inclusion
  dependencies.

  I've built all the working defconfigs from all the arches that I can
  and made sure that they don't break.

  The reason for these patches is that I recently encountered a circular
  dependency problem that came about when I produced some patches to
  optimise get_order() by rewriting it to use ilog2().

  This uses bitops - and on the SH arch asm/bitops.h drags in
  asm-generic/get_order.h by a circuituous route involving asm/system.h.

  The main difficulty seems to be asm/system.h.  It holds a number of
  low level bits with no/few dependencies that are commonly used (eg.
  memory barriers) and a number of bits with more dependencies that
  aren't used in many places (eg.  switch_to()).

  These patches break asm/system.h up into the following core pieces:

    (1) asm/barrier.h

        Move memory barriers here.  This already done for MIPS and Alpha.

    (2) asm/switch_to.h

        Move switch_to() and related stuff here.

    (3) asm/exec.h

        Move arch_align_stack() here.  Other process execution related bits
        could perhaps go here from asm/processor.h.

    (4) asm/cmpxchg.h

        Move xchg() and cmpxchg() here as they're full word atomic ops and
        frequently used by atomic_xchg() and atomic_cmpxchg().

    (5) asm/bug.h

        Move die() and related bits.

    (6) asm/auxvec.h

        Move AT_VECTOR_SIZE_ARCH here.

  Other arch headers are created as needed on a per-arch basis."

Fixed up some conflicts from other header file cleanups and moving code
around that has happened in the meantime, so David's testing is somewhat
weakened by that.  We'll find out anything that got broken and fix it..

* tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits)
  Delete all instances of asm/system.h
  Remove all #inclusions of asm/system.h
  Add #includes needed to permit the removal of asm/system.h
  Move all declarations of free_initmem() to linux/mm.h
  Disintegrate asm/system.h for OpenRISC
  Split arch_align_stack() out from asm-generic/system.h
  Split the switch_to() wrapper out of asm-generic/system.h
  Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h
  Create asm-generic/barrier.h
  Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h
  Disintegrate asm/system.h for Xtensa
  Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]
  Disintegrate asm/system.h for Tile
  Disintegrate asm/system.h for Sparc
  Disintegrate asm/system.h for SH
  Disintegrate asm/system.h for Score
  Disintegrate asm/system.h for S390
  Disintegrate asm/system.h for PowerPC
  Disintegrate asm/system.h for PA-RISC
  Disintegrate asm/system.h for MN10300
  ...
2012-03-28 15:58:21 -07:00
David Howells f05e798ad4 Disintegrate asm/system.h for X86
Disintegrate asm/system.h for X86.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
cc: x86@kernel.org
2012-03-28 18:11:12 +01:00
Linus Torvalds ed2d265d12 The following text was taken from the original review request:
"[RFC - PATCH 0/7] consolidation of BUG support code."
 		https://lkml.org/lkml/2012/1/26/525
 --
 
 The changes shown here are to unify linux's BUG support under
 the one <linux/bug.h> file.  Due to historical reasons, we have
 some BUG code in bug.h and some in kernel.h -- i.e. the support for
 BUILD_BUG in linux/kernel.h predates the addition of linux/bug.h,
 but old code in kernel.h wasn't moved to bug.h at that time.  As
 a band-aid, kernel.h was including <asm/bug.h> to pseudo link them.
 
 This has caused confusion[1] and general yuck/WTF[2] reactions.
 Here is an example that violates the principle of least surprise:
 
       CC      lib/string.o
       lib/string.c: In function 'strlcat':
       lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
       make[2]: *** [lib/string.o] Error 1
       $
       $ grep linux/bug.h lib/string.c
       #include <linux/bug.h>
       $
 
 We've included <linux/bug.h> for the BUG infrastructure and yet we
 still get a compile fail!  [We've not kernel.h for BUILD_BUG_ON.]
 Ugh - very confusing for someone who is new to kernel development.
 
 With the above in mind, the goals of this changeset are:
 
 1) find and fix any include/*.h files that were relying on the
    implicit presence of BUG code.
 2) find and fix any C files that were consuming kernel.h and
    hence relying on implicitly getting some/all BUG code.
 3) Move the BUG related code living in kernel.h to <linux/bug.h>
 4) remove the asm/bug.h from kernel.h to finally break the chain.
 
 During development, the order was more like 3-4, build-test, 1-2.
 But to ensure that git history for bisect doesn't get needless
 build failures introduced, the commits have been reorderd to fix
 the problem areas in advance.
 
 [1]  https://lkml.org/lkml/2012/1/3/90
 [2]  https://lkml.org/lkml/2012/1/17/414
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Merge tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Pull <linux/bug.h> cleanup from Paul Gortmaker:
 "The changes shown here are to unify linux's BUG support under the one
  <linux/bug.h> file.  Due to historical reasons, we have some BUG code
  in bug.h and some in kernel.h -- i.e.  the support for BUILD_BUG in
  linux/kernel.h predates the addition of linux/bug.h, but old code in
  kernel.h wasn't moved to bug.h at that time.  As a band-aid, kernel.h
  was including <asm/bug.h> to pseudo link them.

  This has caused confusion[1] and general yuck/WTF[2] reactions.  Here
  is an example that violates the principle of least surprise:

      CC      lib/string.o
      lib/string.c: In function 'strlcat':
      lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
      make[2]: *** [lib/string.o] Error 1
      $
      $ grep linux/bug.h lib/string.c
      #include <linux/bug.h>
      $

  We've included <linux/bug.h> for the BUG infrastructure and yet we
  still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh -
  very confusing for someone who is new to kernel development.

  With the above in mind, the goals of this changeset are:

  1) find and fix any include/*.h files that were relying on the
     implicit presence of BUG code.
  2) find and fix any C files that were consuming kernel.h and hence
     relying on implicitly getting some/all BUG code.
  3) Move the BUG related code living in kernel.h to <linux/bug.h>
  4) remove the asm/bug.h from kernel.h to finally break the chain.

  During development, the order was more like 3-4, build-test, 1-2.  But
  to ensure that git history for bisect doesn't get needless build
  failures introduced, the commits have been reorderd to fix the problem
  areas in advance.

	[1]  https://lkml.org/lkml/2012/1/3/90
	[2]  https://lkml.org/lkml/2012/1/17/414"

Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul
and linux-next.

* tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
  kernel.h: doesn't explicitly use bug.h, so don't include it.
  bug: consolidate BUILD_BUG_ON with other bug code
  BUG: headers with BUG/BUG_ON etc. need linux/bug.h
  bug.h: add include of it to various implicit C users
  lib: fix implicit users of kernel.h for TAINT_WARN
  spinlock: macroize assert_spin_locked to avoid bug.h dependency
  x86: relocate get/set debugreg fcns to include/asm/debugreg.
2012-03-24 10:08:39 -07:00
Paul Gortmaker 50af5ead3b bug.h: add include of it to various implicit C users
With bug.h currently living right in linux/kernel.h there
are files that use BUG_ON and friends but are not including
the header explicitly.  Fix them up so we can remove the
presence in kernel.h file.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-29 17:15:08 -05:00
Ingo Molnar c5905afb0e static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]()
So here's a boot tested patch on top of Jason's series that does
all the cleanups I talked about and turns jump labels into a
more intuitive to use facility. It should also address the
various misconceptions and confusions that surround jump labels.

Typical usage scenarios:

        #include <linux/static_key.h>

        struct static_key key = STATIC_KEY_INIT_TRUE;

        if (static_key_false(&key))
                do unlikely code
        else
                do likely code

Or:

        if (static_key_true(&key))
                do likely code
        else
                do unlikely code

The static key is modified via:

        static_key_slow_inc(&key);
        ...
        static_key_slow_dec(&key);

The 'slow' prefix makes it abundantly clear that this is an
expensive operation.

I've updated all in-kernel code to use this everywhere. Note
that I (intentionally) have not pushed through the rename
blindly through to the lowest levels: the actual jump-label
patching arch facility should be named like that, so we want to
decouple jump labels from the static-key facility a bit.

On non-jump-label enabled architectures static keys default to
likely()/unlikely() branches.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jason Baron <jbaron@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: a.p.zijlstra@chello.nl
Cc: mathieu.desnoyers@efficios.com
Cc: davem@davemloft.net
Cc: ddaney.cavm@gmail.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24 10:05:59 +01:00
Linus Torvalds 06e727d2a5 Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-tip
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-tip:
  x86-64: Rework vsyscall emulation and add vsyscall= parameter
  x86-64: Wire up getcpu syscall
  x86: Remove unnecessary compile flag tweaks for vsyscall code
  x86-64: Add vsyscall:emulate_vsyscall trace event
  x86-64: Add user_64bit_mode paravirt op
  x86-64, xen: Enable the vvar mapping
  x86-64: Work around gold bug 13023
  x86-64: Move the "user" vsyscall segment out of the data segment.
  x86-64: Pad vDSO to a page boundary
2011-08-12 20:46:24 -07:00
Andy Lutomirski 318f5a2a67 x86-64: Add user_64bit_mode paravirt op
Three places in the kernel assume that the only long mode CPL 3
selector is __USER_CS.  This is not true on Xen -- Xen's sysretq
changes cs to the magic value 0xe033.

Two of the places are corner cases, but as of "x86-64: Improve
vsyscall emulation CS and RIP handling"
(c9712944b2), vsyscalls will segfault
if called with Xen's extra CS selector.  This causes a panic when
older init builds die.

It seems impossible to make Xen use __USER_CS reliably without
taking a performance hit on every system call, so this fixes the
tests instead with a new paravirt op.  It's a little ugly because
ptrace.h can't include paravirt.h.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Link: http://lkml.kernel.org/r/f4fcb3947340d9e96ce1054a432f183f9da9db83.1312378163.git.luto@mit.edu
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-08-04 16:13:49 -07:00
Glauber Costa 3c404b578f KVM guest: Add a pv_ops stub for steal time
This patch adds a function pointer in one of the many paravirt_ops
structs, to allow guests to register a steal time function. Besides
a steal time function, we also declare two jump_labels. They will be
used to allow the steal time code to be easily bypassed when not
in use.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Eric B Munson <emunson@mgebm.net>
CC: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-07-14 12:59:44 +03:00
Andrea Arcangeli 331127f799 thp: add pmd paravirt ops
Paravirt ops pmd_update/pmd_update_defer/pmd_set_at.  Not all might be
necessary (vmware needs pmd_update, Xen needs set_pmd_at, nobody needs
pmd_update_defer), but this is to keep full simmetry with pte paravirt
ops, which looks cleaner and simpler from a common code POV.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:39 -08:00
Alok Kataria b0f4c062fb x86, paravirt: Remove alloc_pmd_clone hook, only used by VMI
VMI was the only user of the alloc_pmd_clone hook, given that VMI
is now removed we can also remove this hook.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
LKML-Reference: <1282608357.19396.36.camel@ank32.eng.vmware.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-08-23 17:09:44 -07:00
Ian Campbell dad52fc011 x86, paravirt: Remove kmap_atomic_pte paravirt op.
Now that both Xen and VMI disable allocations of PTE pages from high
memory this paravirt op serves no further purpose.

This effectively reverts ce6234b5 "add kmap_atomic_pte for mapping
highpte pages".

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
LKML-Reference: <1267204562-11844-3-git-send-email-ian.campbell@citrix.com>
Acked-by: Alok Kataria <akataria@vmware.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-27 14:41:35 -08:00
Linus Torvalds 78f28b7c55 Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (38 commits)
  x86: Move get/set_wallclock to x86_platform_ops
  x86: platform: Fix section annotations
  x86: apic namespace cleanup
  x86: Distangle ioapic and i8259
  x86: Add Moorestown early detection
  x86: Add hardware_subarch ID for Moorestown
  x86: Add early platform detection
  x86: Move tsc_init to late_time_init
  x86: Move tsc_calibration to x86_init_ops
  x86: Replace the now identical time_32/64.c by time.c
  x86: time_32/64.c unify profile_pc
  x86: Move calibrate_cpu to tsc.c
  x86: Make timer setup and global variables the same in time_32/64.c
  x86: Remove mca bus ifdef from timer interrupt
  x86: Simplify timer_ack magic in time_32.c
  x86: Prepare unification of time_32/64.c
  x86: Remove do_timer hook
  x86: Add timer_init to x86_init_ops
  x86: Move percpu clockevents setup to x86_init_ops
  x86: Move xen_post_allocator_init into xen_pagetable_setup_done
  ...

Fix up conflicts in arch/x86/include/asm/io_apic.h
2009-09-18 14:05:47 -07:00
Feng Tang 7bd867dfb4 x86: Move get/set_wallclock to x86_platform_ops
get/set_wallclock() have already a set of platform dependent
implementations (default, EFI, paravirt). MRST will add another
variant.

Moving them to platform ops simplifies the existing code and minimizes
the effort to integrate new variants.

Signed-off-by: Feng Tang <feng.tang@intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-09-16 14:34:50 +02:00
Borislav Petkov 177fed1ee8 x86, msr: Rewrite AMD rd/wrmsr variants
Switch them to native_{rd,wr}msr_safe_regs and remove
pv_cpu_ops.read_msr_amd.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
LKML-Reference: <1251705011-18636-2-git-send-email-petkovbb@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-31 15:14:28 -07:00
Borislav Petkov 132ec92f3f x86, msr: Add rd/wrmsr interfaces with preset registers
native_{rdmsr,wrmsr}_safe_regs are two new interfaces which allow
presetting of a subset of eight x86 GPRs before executing the rd/wrmsr
instructions. This is needed at least on AMD K8 for accessing an erratum
workaround MSR.

Originally based on an idea by H. Peter Anvin.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
LKML-Reference: <1251705011-18636-1-git-send-email-petkovbb@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-31 15:14:26 -07:00
Thomas Gleixner 2d826404f0 x86: Move tsc_calibration to x86_init_ops
TSC calibration is modified by the vmware hypervisor and paravirt by
separate means. Moorestown wants to add its own calibration routine as
well. So make calibrate_tsc a proper x86_init_ops function and
override it by paravirt or by the early setup of the vmware
hypervisor.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:47 +02:00
Thomas Gleixner 845b3944bb x86: Add timer_init to x86_init_ops
The timer init code is convoluted with several quirks and the paravirt
timer chooser. Figuring out which code path is actually taken is not
for the faint hearted.

Move the numaq TSC quirk to tsc_pre_init x86_init_ops function and
replace the paravirt time chooser and the remaining x86 quirk with a
simple x86_init_ops function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner 736decac64 x86: Move percpu clockevents setup to x86_init_ops
paravirt overrides the setup of the default apic timers as per cpu
timers. Moorestown needs to override that as well.

Move it to x86_init_ops setup and create a separate x86_cpuinit struct
which holds the function for the secondary evtl. hotplugabble CPUs.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner 030cb6c00d x86: Move paravirt pagetable_setup to x86_init_ops
Replace more paravirt hackery by proper x86_init_ops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner 6f30c1ac3f x86: Move paravirt banner printout to x86_init_ops
Replace another obscure paravirt magic and move it to
x86_init_ops. Such a hook is also useful for embedded and special
hardware.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner 42bbdb43b1 x86: Replace ARCH_SETUP by a proper x86_init_ops
ARCH_SETUP is a horrible leftover from the old arch/i386 mach support
code. It still has a lonely user in xen. Move it to x86_init_ops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner 66bcaf0bde x86: Move irq_init to x86_init_ops
irq_init is overridden by x86_quirks and by paravirts. Unify the whole
mess and make it an unconditional x86_init_ops function which defaults
to the standard function and can be overridden by the early platform
code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner 6b18ae3e2f x86: Move memory_setup to x86_init_ops
memory_setup is overridden by x86_quirks and by paravirts with weak
functions and quirks. Unify the whole mess and make it an
unconditional x86_init_ops function which defaults to the standard
function and can be overridden by the early platform code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
Linus Torvalds be15f9d63b Merge branch 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (42 commits)
  xen: cache cr0 value to avoid trap'n'emulate for read_cr0
  xen/x86-64: clean up warnings about IST-using traps
  xen/x86-64: fix breakpoints and hardware watchpoints
  xen: reserve Xen start_info rather than e820 reserving
  xen: add FIX_TEXT_POKE to fixmap
  lguest: update lazy mmu changes to match lguest's use of kvm hypercalls
  xen: honour VCPU availability on boot
  xen: add "capabilities" file
  xen: drop kexec bits from /sys/hypervisor since kexec isn't implemented yet
  xen/sys/hypervisor: change writable_pt to features
  xen: add /sys/hypervisor support
  xen/xenbus: export xenbus_dev_changed
  xen: use device model for suspending xenbus devices
  xen: remove suspend_cancel hook
  xen/dev-evtchn: clean up locking in evtchn
  xen: export ioctl headers to userspace
  xen: add /dev/xen/evtchn driver
  xen: add irq_from_evtchn
  xen: clean up gate trap/interrupt constants
  xen: set _PAGE_NX in __supported_pte_mask before pagetable construction
  ...
2009-06-10 16:16:27 -07:00
Jeremy Fitzhardinge b4ecc12699 x86: Fix performance regression caused by paravirt_ops on native kernels
Xiaohui Xin and some other folks at Intel have been looking into what's
behind the performance hit of paravirt_ops when running native.

It appears that the hit is entirely due to the paravirtualized
spinlocks introduced by:

 | commit 8efcbab674
 | Date:   Mon Jul 7 12:07:51 2008 -0700
 |
 |     paravirt: introduce a "lock-byte" spinlock implementation

The extra call/return in the spinlock path is somehow
causing an increase in the cycles/instruction of somewhere around 2-7%
(seems to vary quite a lot from test to test).  The working theory is
that the CPU's pipeline is getting upset about the
call->call->locked-op->return->return, and seems to be failing to
speculate (though I haven't seen anything definitive about the precise
reasons).  This doesn't entirely make sense, because the performance
hit is also visible on unlock and other operations which don't involve
locked instructions.  But spinlock operations clearly swamp all the
other pvops operations, even though I can't imagine that they're
nearly as common (there's only a .05% increase in instructions
executed).

If I disable just the pv-spinlock calls, my tests show that pvops is
identical to non-pvops performance on native (my measurements show that
it is actually about .1% faster, but Xiaohui shows a .05% slowdown).

Summary of results, averaging 10 runs of the "mmperf" test, using a
no-pvops build as baseline:

		nopv		Pv-nospin	Pv-spin
CPU cycles	100.00%		99.89%		102.18%
instructions	100.00%		100.10%		100.15%
CPI		100.00%		99.79%		102.03%
cache ref	100.00%		100.84%		100.28%
cache miss	100.00%		90.47%		88.56%
cache miss rate	100.00%		89.72%		88.31%
branches	100.00%		99.93%		100.04%
branch miss	100.00%		103.66%		107.72%
branch miss rt	100.00%		103.73%		107.67%
wallclock	100.00%		99.90%		102.20%

The clear effect here is that the 2% increase in CPI is
directly reflected in the final wallclock time.

(The other interesting effect is that the more ops are
out of line calls via pvops, the lower the cache access
and miss rates.  Not too surprising, but it suggests that
the non-pvops kernel is over-inlined.  On the flipside,
the branch misses go up correspondingly...)

So, what's the fix?

Paravirt patching turns all the pvops calls into direct calls, so
_spin_lock etc do end up having direct calls.  For example, the compiler
generated code for paravirtualized _spin_lock is:

<_spin_lock+0>:		mov    %gs:0xb4c8,%rax
<_spin_lock+9>:		incl   0xffffffffffffe044(%rax)
<_spin_lock+15>:	callq  *0xffffffff805a5b30
<_spin_lock+22>:	retq

The indirect call will get patched to:
<_spin_lock+0>:		mov    %gs:0xb4c8,%rax
<_spin_lock+9>:		incl   0xffffffffffffe044(%rax)
<_spin_lock+15>:	callq <__ticket_spin_lock>
<_spin_lock+20>:	nop; nop		/* or whatever 2-byte nop */
<_spin_lock+22>:	retq

One possibility is to inline _spin_lock, etc, when building an
optimised kernel (ie, when there's no spinlock/preempt
instrumentation/debugging enabled).  That will remove the outer
call/return pair, returning the instruction stream to a single
call/return, which will presumably execute the same as the non-pvops
case.  The downsides arel 1) it will replicate the
preempt_disable/enable code at eack lock/unlock callsite; this code is
fairly small, but not nothing; and 2) the spinlock definitions are
already a very heavily tangled mass of #ifdefs and other preprocessor
magic, and making any changes will be non-trivial.

The other obvious answer is to disable pv-spinlocks.  Making them a
separate config option is fairly easy, and it would be trivial to
enable them only when Xen is enabled (as the only non-default user).
But it doesn't really address the common case of a distro build which
is going to have Xen support enabled, and leaves the open question of
whether the native performance cost of pv-spinlocks is worth the
performance improvement on a loaded Xen system (10% saving of overall
system CPU when guests block rather than spin).  Still it is a
reasonable short-term workaround.

[ Impact: fix pvops performance regression when running native ]

Analysed-by: "Xin Xiaohui" <xiaohui.xin@intel.com>
Analysed-by: "Li Xin" <xin.li@intel.com>
Analysed-by: "Nakajima Jun" <jun.nakajima@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Xen-devel <xen-devel@lists.xensource.com>
LKML-Reference: <4A0B62F7.5030802@goop.org>
[ fixed the help text ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-15 20:07:42 +02:00
Jeremy Fitzhardinge 38f4b8c0da Merge commit 'origin/master' into for-linus/xen/master
* commit 'origin/master': (4825 commits)
  Fix build errors due to CONFIG_BRANCH_TRACER=y
  parport: Use the PCI IRQ if offered
  tty: jsm cleanups
  Adjust path to gpio headers
  KGDB_SERIAL_CONSOLE check for module
  Change KCONFIG name
  tty: Blackin CTS/RTS
  Change hardware flow control from poll to interrupt driven
  Add support for the MAX3100 SPI UART.
  lanana: assign a device name and numbering for MAX3100
  serqt: initial clean up pass for tty side
  tty: Use the generic RS485 ioctl on CRIS
  tty: Correct inline types for tty_driver_kref_get()
  splice: fix deadlock in splicing to file
  nilfs2: support nanosecond timestamp
  nilfs2: introduce secondary super block
  nilfs2: simplify handling of active state of segments
  nilfs2: mark minor flag for checkpoint created by internal operation
  nilfs2: clean up sketch file
  nilfs2: super block operations fix endian bug
  ...

Conflicts:
	arch/x86/include/asm/thread_info.h
	arch/x86/lguest/boot.c
	drivers/xen/manage.c
2009-04-07 13:34:16 -07:00
Jeremy Fitzhardinge ab2f75f0b7 x86/paravirt: use percpu_ rather than __get_cpu_var
Impact: minor optimisation

percpu_read/write is a slightly more direct way of getting
to percpu data.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-03-29 23:36:04 -07:00
Jeremy Fitzhardinge 2829b44927 x86/paravirt: allow preemption with lazy mmu mode
Impact: remove obsolete checks, simplification

Lift restrictions on preemption with lazy mmu mode, as it is now allowed.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2009-03-29 23:36:02 -07:00
Jeremy Fitzhardinge 224101ed69 x86/paravirt: finish change from lazy cpu to context switch start/end
Impact: fix lazy context switch API

Pass the previous and next tasks into the context switch start
end calls, so that the called functions can properly access the
task state (esp in end_context_switch, in which the next task
is not yet completely current).

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2009-03-29 23:36:01 -07:00
Jeremy Fitzhardinge b407fc57b8 x86/paravirt: flush pending mmu updates on context switch
Impact: allow preemption during lazy mmu updates

If we're in lazy mmu mode when context switching, leave
lazy mmu mode, but remember the task's state in
TIF_LAZY_MMU_UPDATES.  When we resume the task, check this
flag and re-enter lazy mmu mode if its set.

This sets things up for allowing lazy mmu mode while preemptible,
though that won't actually be active until the next change.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2009-03-29 23:36:00 -07:00
Jeremy Fitzhardinge 7fd7d83d49 x86/pvops: replace arch_enter_lazy_cpu_mode with arch_start_context_switch
Impact: simplification, prepare for later changes

Make lazy cpu mode more specific to context switching, so that
it makes sense to do more context-switch specific things in
the callbacks.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2009-03-29 23:35:59 -07:00
Jeremy Fitzhardinge b8bcfe997e x86/paravirt: remove lazy mode in interrupts
Impact: simplification, robustness

Make paravirt_lazy_mode() always return PARAVIRT_LAZY_NONE
when in an interrupt.  This prevents interrupt code from
accidentally inheriting an outer lazy state, and instead
does everything synchronously.  Outer batched operations
are left deferred.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
2009-03-29 23:35:38 -07:00
Jeremy Fitzhardinge 71ff49d71b x86: with the last user gone, remove set_pte_present
Impact: cleanup

set_pte_present() is no longer used, directly or indirectly,
so remove it.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
LKML-Reference: <1237406613-2929-2-git-send-email-jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-19 14:04:19 +01:00
Ingo Molnar 8e6dafd6c7 x86: refactor x86_quirks support
Impact: cleanup

Make x86_quirks support more transparent. The highlevel
methods are now named:

  extern void x86_quirk_pre_intr_init(void);
  extern void x86_quirk_intr_init(void);

  extern void x86_quirk_trap_init(void);

  extern void x86_quirk_pre_time_init(void);
  extern void x86_quirk_time_init(void);

This makes it clear that if some platform extension has to
do something here that it is considered ... weird, and is
discouraged.

Also remove arch_hooks.h and move it into setup.h (and other
header files where appropriate).

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-23 00:08:11 +01:00
Ingo Molnar 7032e86967 Merge branches 'x86/paravirt', 'x86/pat', 'x86/setup-v2', 'x86/subarch', 'x86/uaccess' and 'x86/urgent' into x86/core 2009-02-13 09:47:32 +01:00
Thomas Gleixner 34b0900d32 x86: warn if arch_flush_lazy_mmu_cpu is called in preemptible context
Impact: Catch cases where lazy MMU state is active in a preemtible context

arch_flush_lazy_mmu_cpu() has been changed to disable preemption so
the checks in enter/leave will never trigger. Put the preemtible()
check into arch_flush_lazy_mmu_cpu() to catch such cases.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-02-12 23:11:58 +01:00
Jeremy Fitzhardinge d85cf93da6 x86/paravirt: make arch_flush_lazy_mmu/cpu disable preemption
Impact: avoid access to percpu vars in preempible context

They are intended to be used whenever there's the possibility
that there's some stale state which is going to be overwritten
with a queued update, or to force a state change when we may be
in lazy mode.  Either way, we could end up calling it with
preemption enabled, so wrap the functions in their own little
preempt-disable section so they can be safely called in any
context (though preemption should never be enabled if we're actually
in a lazy state).

(Move out of line to avoid #include dependencies.)
    
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-02-12 23:11:58 +01:00
Jeremy Fitzhardinge da5de7c22e x86/paravirt: use callee-saved convention for pte_val/make_pte/etc
Impact: Optimization

In the native case, pte_val, make_pte, etc are all just identity
functions, so there's no need to clobber a lot of registers over them.

(This changes the 32-bit callee-save calling convention to return both
EAX and EDX so functions can return 64-bit values.)

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-01-30 14:51:45 -08:00