Commit Graph

19835 Commits

Author SHA1 Message Date
Tejun Heo ffda22c1f3 time: use %*pb[l] to print bitmaps including cpumasks and nodemasks
printk and friends can now format bitmaps using '%*pb[l]'.  cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:37 -08:00
Tejun Heo 333470ee46 sched: use %*pb[l] to print bitmaps including cpumasks and nodemasks
printk and friends can now format bitmaps using '%*pb[l]'.  cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:37 -08:00
Tejun Heo ad853b48cb rcu: use %*pb[l] to print bitmaps including cpumasks and nodemasks
printk and friends can now format bitmaps using '%*pb[l]'.  cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:37 -08:00
Tejun Heo e8e6d97c9b cpuset: use %*pb[l] to print bitmaps including cpumasks and nodemasks
printk and friends can now format bitmaps using '%*pb[l]'.  cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.

* kernel/cpuset.c::cpuset_print_task_mems_allowed() used a static
  buffer which is protected by a dedicated spinlock.  Removed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:37 -08:00
Tejun Heo dfeb0750b6 kernfs: remove KERNFS_STATIC_NAME
When a new kernfs node is created, KERNFS_STATIC_NAME is used to avoid
making a separate copy of its name.  It's currently only used for sysfs
attributes whose filenames are required to stay accessible and unchanged.
There are rare exceptions where these names are allocated and formatted
dynamically but for the vast majority of cases they're consts in the
rodata section.

Now that kernfs is converted to use kstrdup_const() and kfree_const(),
there's little point in keeping KERNFS_STATIC_NAME around.  Remove it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:36 -08:00
Rafael J. Wysocki affe3e85ae timekeeping: Pass readout base to update_fast_timekeeper()
Modify update_fast_timekeeper() to take a struct tk_read_base
pointer as its argument (instead of a struct timekeeper pointer)
and update its kerneldoc comment to reflect that.

That will allow a struct tk_read_base that is not part of a
struct timekeeper to be passed to it in the next patch.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: John Stultz <john.stultz@linaro.org>
2015-02-13 23:49:36 +01:00
Rafael J. Wysocki 3810631332 PM / sleep: Re-implement suspend-to-idle handling
In preparation for adding support for quiescing timers in the final
stage of suspend-to-idle transitions, rework the freeze_enter()
function making the system wait on a wakeup event, the freeze_wake()
function terminating the suspend-to-idle loop and the mechanism by
which deep idle states are entered during suspend-to-idle.

First of all, introduce a simple state machine for suspend-to-idle
and make the code in question use it.

Second, prevent freeze_enter() from losing wakeup events due to race
conditions and ensure that the number of online CPUs won't change
while it is being executed.  In addition to that, make it force
all of the CPUs re-enter the idle loop in case they are in idle
states already (so they can enter deeper idle states if possible).

Next, drop cpuidle_use_deepest_state() and replace use_deepest_state
checks in cpuidle_select() and cpuidle_reflect() with a single
suspend-to-idle state check in cpuidle_idle_call().

Finally, introduce cpuidle_enter_freeze() that will simply find the
deepest idle state available to the given CPU and enter it using
cpuidle_enter().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2015-02-13 23:49:36 +01:00
Linus Torvalds a42cf70eb8 Trivial cleanups, mainly.
Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module update from Rusty Russell:
 "Trivial cleanups, mainly"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  module: Replace over-engineered nested sleep
  module: Annotate nested sleep in resolve_symbol()
  module: Remove double spaces in module verification taint message
  kernel/module.c: Free lock-classes if parse_args failed
  module: set ksymtab/kcrctab* section addresses to 0x0
2015-02-13 10:47:13 -08:00
Joe Perches 205bd3d23e printk: correct timeout comment, neaten MODULE_PARM_DESC
Neaten the MODULE_PARAM_DESC message.
Use 30 seconds in the comment for the zap console locks timeout.

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>
2015-02-12 18:54:13 -08:00
Cyril Bur 545a2bf742 kernel/sched/clock.c: add another clock for use with the soft lockup watchdog
When the hypervisor pauses a virtualised kernel the kernel will observe a
jump in timebase, this can cause spurious messages from the softlockup
detector.

Whilst these messages are harmless, they are accompanied with a stack
trace which causes undue concern and more problematically the stack trace
in the guest has nothing to do with the observed problem and can only be
misleading.

Futhermore, on POWER8 this is completely avoidable with the introduction
of the Virtual Time Base (VTB) register.

This patch (of 2):

This permits the use of arch specific clocks for which virtualised kernels
can use their notion of 'running' time, not the elpased wall time which
will include host execution time.

Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andrew Jones <drjones@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: chai wen <chaiw.fnst@cn.fujitsu.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Ben Zhang <benzh@chromium.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:13 -08:00
Andy Lutomirski f56141e3e2 all arches, signal: move restart_block to struct task_struct
If an attacker can cause a controlled kernel stack overflow, overwriting
the restart block is a very juicy exploit target.  This is because the
restart_block is held in the same memory allocation as the kernel stack.

Moving the restart block to struct task_struct prevents this exploit by
making the restart_block harder to locate.

Note that there are other fields in thread_info that are also easy
targets, at least on some architectures.

It's also a decent simplification, since the restart code is more or less
identical on all architectures.

[james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Miller <davem@davemloft.net>
Acked-by: Richard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.linux@gmail.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:12 -08:00
Rasmus Villemoes 8f4ab07f4b kernel/cpuset.c: Mark cpuset_init_current_mems_allowed as __init
The only caller of cpuset_init_current_mems_allowed is the __init
annotated build_all_zonelists_init, so we can also make the former __init.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vishnu Pratap Singh <vishnu.ps@samsung.com>
Cc: Pintu Kumar <pintu.k@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Li Zefan <lizefan@huawei.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>
2015-02-12 18:54:11 -08:00
Kirill A. Shutemov 2d2f5119b8 mm: do not use mm->nr_pmds on !MMU configurations
mm->nr_pmds doesn't make sense on !MMU configurations

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:10 -08:00
Vladimir Davydov 01e586598b cgroup: release css->id after css_free
Currently, we release css->id in css_release_work_fn, right before calling
css_free callback, so that when css_free is called, the id may have
already been reused for a new cgroup.

I am going to use css->id to create unique names for per memcg kmem
caches.  Since kmem caches are destroyed only on css_free, I need css->id
to be freed after css_free was called to avoid name clashes.  This patch
therefore moves css->id removal to css_free_work_fn.  To prevent
css_from_id from returning a pointer to a stale css, it makes
css_release_work_fn replace the css ptr at css_idr:css->id with NULL.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Acked-by: Tejun Heo <tj@kernel.org>
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>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:09 -08:00
Linus Torvalds 42cf0f203e Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:

 - clang assembly fixes from Ard

 - optimisations and cleanups for Aurora L2 cache support

 - efficient L2 cache support for secure monitor API on Exynos SoCs

 - debug menu cleanup from Daniel Thompson to allow better behaviour for
   multiplatform kernels

 - StrongARM SA11x0 conversion to irq domains, and pxa_timer

 - kprobes updates for older ARM CPUs

 - move probes support out of arch/arm/kernel to arch/arm/probes

 - add inline asm support for the rbit (reverse bits) instruction

 - provide an ARM mode secondary CPU entry point (for Qualcomm CPUs)

 - remove the unused ARMv3 user access code

 - add driver_override support to AMBA Primecell bus

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (55 commits)
  ARM: 8256/1: driver coamba: add device binding path 'driver_override'
  ARM: 8301/1: qcom: Use secondary_startup_arm()
  ARM: 8302/1: Add a secondary_startup that assumes ARM mode
  ARM: 8300/1: teach __asmeq that r11 == fp and r12 == ip
  ARM: kprobes: Fix compilation error caused by superfluous '*'
  ARM: 8297/1: cache-l2x0: optimize aurora range operations
  ARM: 8296/1: cache-l2x0: clean up aurora cache handling
  ARM: 8284/1: sa1100: clear RCSR_SMR on resume
  ARM: 8283/1: sa1100: collie: clear PWER register on machine init
  ARM: 8282/1: sa1100: use handle_domain_irq
  ARM: 8281/1: sa1100: move GPIO-related IRQ code to gpio driver
  ARM: 8280/1: sa1100: switch to irq_domain_add_simple()
  ARM: 8279/1: sa1100: merge both GPIO irqdomains
  ARM: 8278/1: sa1100: split irq handling for low GPIOs
  ARM: 8291/1: replace magic number with PAGE_SHIFT macro in fixup_pv code
  ARM: 8290/1: decompressor: fix a wrong comment
  ARM: 8286/1: mm: Fix dma_contiguous_reserve comment
  ARM: 8248/1: pm: remove outdated comment
  ARM: 8274/1: Fix DEBUG_LL for multi-platform kernels (without PL01X)
  ARM: 8273/1: Seperate DEBUG_UART_PHYS from DEBUG_LL on EP93XX
  ...
2015-02-12 08:51:56 -08:00
Linus Torvalds 41cbc01f6e The updates included in this pull request for ftrace are:
o Several clean ups to the code
 
    One such clean up was to convert to 64 bit time keeping, in the
    ring buffer benchmark code.
 
  o Adding of __print_array() helper macro for TRACE_EVENT()
 
  o Updating the sample/trace_events/ to add samples of different ways to
    make trace events. Lots of features have been added since the sample
    code was made, and these features are mostly unknown. Developers
    have been making their own hacks to do things that are already available.
 
  o Performance improvements. Most notably, I found a performance bug where
    a waiter that is waiting for a full page from the ring buffer will
    see that a full page is not available, and go to sleep. The sched
    event caused by it going to sleep would cause it to wake up again.
    It would see that there was still not a full page, and go back to sleep
    again, and that would wake it up again, until finally it would see a
    full page. This change has been marked for stable.
 
    Other improvements include removing global locks from fast paths.
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Merge tag 'trace-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The updates included in this pull request for ftrace are:

   o Several clean ups to the code

     One such clean up was to convert to 64 bit time keeping, in the
     ring buffer benchmark code.

   o Adding of __print_array() helper macro for TRACE_EVENT()

   o Updating the sample/trace_events/ to add samples of different ways
     to make trace events.  Lots of features have been added since the
     sample code was made, and these features are mostly unknown.
     Developers have been making their own hacks to do things that are
     already available.

   o Performance improvements.  Most notably, I found a performance bug
     where a waiter that is waiting for a full page from the ring buffer
     will see that a full page is not available, and go to sleep.  The
     sched event caused by it going to sleep would cause it to wake up
     again.  It would see that there was still not a full page, and go
     back to sleep again, and that would wake it up again, until finally
     it would see a full page.  This change has been marked for stable.

  Other improvements include removing global locks from fast paths"

* tag 'trace-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ring-buffer: Do not wake up a splice waiter when page is not full
  tracing: Fix unmapping loop in tracing_mark_write
  tracing: Add samples of DECLARE_EVENT_CLASS() and DEFINE_EVENT()
  tracing: Add TRACE_EVENT_FN example
  tracing: Add TRACE_EVENT_CONDITION sample
  tracing: Update the TRACE_EVENT fields available in the sample code
  tracing: Separate out initializing top level dir from instances
  tracing: Make tracing_init_dentry_tr() static
  trace: Use 64-bit timekeeping
  tracing: Add array printing helper
  tracing: Remove newline from trace_printk warning banner
  tracing: Use IS_ERR() check for return value of tracing_init_dentry()
  tracing: Remove unneeded includes of debugfs.h and fs.h
  tracing: Remove taking of trace_types_lock in pipe files
  tracing: Add ref count to tracer for when they are being read by pipe
2015-02-12 08:37:41 -08:00
Paul Burton 9791554b45 MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS
Userland code may be built using an ABI which permits linking to objects
that have more restrictive floating point requirements. For example,
userland code may be built to target the O32 FPXX ABI. Such code may be
linked with other FPXX code, or code built for either one of the more
restrictive FP32 or FP64. When linking with more restrictive code, the
overall requirement of the process becomes that of the more restrictive
code. The kernel has no way to know in advance which mode the process
will need to be executed in, and indeed it may need to change during
execution. The dynamic loader is the only code which will know the
overall required mode, and so it needs to have a means to instruct the
kernel to switch the FP mode of the process.

This patch introduces 2 new options to the prctl syscall which provide
such a capability. The FP mode of the process is represented as a
simple bitmask combining a number of mode bits mirroring those present
in the hardware. Userland can either retrieve the current FP mode of
the process:

  mode = prctl(PR_GET_FP_MODE);

or modify the current FP mode of the process:

  err = prctl(PR_SET_FP_MODE, new_mode);

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matthew Fortune <matthew.fortune@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8899/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-02-12 12:30:29 +01:00
Linus Torvalds 8cc748aa76 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security layer updates from James Morris:
 "Highlights:

   - Smack adds secmark support for Netfilter
   - /proc/keys is now mandatory if CONFIG_KEYS=y
   - TPM gets its own device class
   - Added TPM 2.0 support
   - Smack file hook rework (all Smack users should review this!)"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (64 commits)
  cipso: don't use IPCB() to locate the CIPSO IP option
  SELinux: fix error code in policydb_init()
  selinux: add security in-core xattr support for pstore and debugfs
  selinux: quiet the filesystem labeling behavior message
  selinux: Remove unused function avc_sidcmp()
  ima: /proc/keys is now mandatory
  Smack: Repair netfilter dependency
  X.509: silence asn1 compiler debug output
  X.509: shut up about included cert for silent build
  KEYS: Make /proc/keys unconditional if CONFIG_KEYS=y
  MAINTAINERS: email update
  tpm/tpm_tis: Add missing ifdef CONFIG_ACPI for pnp_acpi_device
  smack: fix possible use after frees in task_security() callers
  smack: Add missing logging in bidirectional UDS connect check
  Smack: secmark support for netfilter
  Smack: Rework file hooks
  tpm: fix format string error in tpm-chip.c
  char/tpm/tpm_crb: fix build error
  smack: Fix a bidirectional UDS connect check typo
  smack: introduce a special case for tmpfs in smack_d_instantiate()
  ...
2015-02-11 20:25:11 -08:00
Linus Torvalds 7184487f14 Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit
Pull audit fix from Paul Moore:
 "Just one patch from the audit tree for v3.20, and a very minor one at
  that.

  The patch simply removes an old, unused field from the audit_krule
  structure, a private audit-only struct.  In audit related news, we did
  a proper overhaul of the audit pathname code and removed the nasty
  getname()/putname() hacks for audit, you should see those patches in
  Al's vfs tree if you haven't already.

  That's it for audit this time, let's hope for a quiet -rcX series"

* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
  audit: remove vestiges of vers_ops
2015-02-11 20:07:47 -08:00
Linus Torvalds 59d53737a8 Merge branch 'akpm' (patches from Andrew)
Merge second set of updates from Andrew Morton:
 "More of MM"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (83 commits)
  mm/nommu.c: fix arithmetic overflow in __vm_enough_memory()
  mm/mmap.c: fix arithmetic overflow in __vm_enough_memory()
  vmstat: Reduce time interval to stat update on idle cpu
  mm/page_owner.c: remove unnecessary stack_trace field
  Documentation/filesystems/proc.txt: describe /proc/<pid>/map_files
  mm: incorporate read-only pages into transparent huge pages
  vmstat: do not use deferrable delayed work for vmstat_update
  mm: more aggressive page stealing for UNMOVABLE allocations
  mm: always steal split buddies in fallback allocations
  mm: when stealing freepages, also take pages created by splitting buddy page
  mincore: apply page table walker on do_mincore()
  mm: /proc/pid/clear_refs: avoid split_huge_page()
  mm: pagewalk: fix misbehavior of walk_page_range for vma(VM_PFNMAP)
  mempolicy: apply page table walker on queue_pages_range()
  arch/powerpc/mm/subpage-prot.c: use walk->vma and walk_page_vma()
  memcg: cleanup preparation for page table walk
  numa_maps: remove numa_maps->vma
  numa_maps: fix typo in gather_hugetbl_stats
  pagemap: use walk->vma instead of calling find_vma()
  clear_refs: remove clear_refs_private->vma and introduce clear_refs_test_walk()
  ...
2015-02-11 18:23:28 -08:00
Linus Torvalds d3f180ea1a powerpc updates for 3.20
Including:
 
 - Update of all defconfigs
 - Addition of a bunch of config options to modernise our defconfigs
 - Some PS3 updates from Geoff
 - Optimised memcmp for 64 bit from Anton
 - Fix for kprobes that allows 'perf probe' to work from Naveen
 - Several cxl updates from Ian & Ryan
 - Expanded support for the '24x7' PMU from Cody & Sukadev
 - Freescale updates from Scott:
   "Highlights include 8xx optimizations, some more work on datapath device
    tree content, e300 machine check support, t1040 corenet error reporting,
    and various cleanups and fixes."
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Merge tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull powerpc updates from Michael Ellerman:

 - Update of all defconfigs

 - Addition of a bunch of config options to modernise our defconfigs

 - Some PS3 updates from Geoff

 - Optimised memcmp for 64 bit from Anton

 - Fix for kprobes that allows 'perf probe' to work from Naveen

 - Several cxl updates from Ian & Ryan

 - Expanded support for the '24x7' PMU from Cody & Sukadev

 - Freescale updates from Scott:
    "Highlights include 8xx optimizations, some more work on datapath
     device tree content, e300 machine check support, t1040 corenet
     error reporting, and various cleanups and fixes"

* tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (102 commits)
  cxl: Add missing return statement after handling AFU errror
  cxl: Fail AFU initialisation if an invalid configuration record is found
  cxl: Export optional AFU configuration record in sysfs
  powerpc/mm: Warn on flushing tlb page in kernel context
  powerpc/powernv: Add OPAL soft-poweroff routine
  powerpc/perf/hv-24x7: Document sysfs event description entries
  powerpc/perf/hv-gpci: add the remaining gpci requests
  powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated
  powerpc/perf/hv-24x7: parse catalog and populate sysfs with events
  perf: define EVENT_DEFINE_RANGE_FORMAT_LITE helper
  perf: add PMU_EVENT_ATTR_STRING() helper
  perf: provide sysfs_show for struct perf_pmu_events_attr
  powerpc/kernel: Avoid initializing device-tree pointer twice
  powerpc: Remove old compile time disabled syscall tracing code
  powerpc/kernel: Make syscall_exit a local label
  cxl: Fix device_node reference counting
  powerpc/mm: bail out early when flushing TLB page
  powerpc: defconfigs: add MTD_SPI_NOR (new dependency for M25P80)
  perf/powerpc: reset event hw state when adding it to the PMU
  powerpc/qe: Use strlcpy()
  ...
2015-02-11 18:15:38 -08:00
Linus Torvalds b3d6524ff7 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:

 - The remaining patches for the z13 machine support: kernel build
   option for z13, the cache synonym avoidance, SMT support,
   compare-and-delay for spinloops and the CES5S crypto adapater.

 - The ftrace support for function tracing with the gcc hotpatch option.
   This touches common code Makefiles, Steven is ok with the changes.

 - The hypfs file system gets an extension to access diagnose 0x0c data
   in user space for performance analysis for Linux running under z/VM.

 - The iucv hvc console gets wildcard spport for the user id filtering.

 - The cacheinfo code is converted to use the generic infrastructure.

 - Cleanup and bug fixes.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (42 commits)
  s390/process: free vx save area when releasing tasks
  s390/hypfs: Eliminate hypfs interval
  s390/hypfs: Add diagnose 0c support
  s390/cacheinfo: don't use smp_processor_id() in preemptible context
  s390/zcrypt: fixed domain scanning problem (again)
  s390/smp: increase maximum value of NR_CPUS to 512
  s390/jump label: use different nop instruction
  s390/jump label: add sanity checks
  s390/mm: correct missing space when reporting user process faults
  s390/dasd: cleanup profiling
  s390/dasd: add locking for global_profile access
  s390/ftrace: hotpatch support for function tracing
  ftrace: let notrace function attribute disable hotpatching if necessary
  ftrace: allow architectures to specify ftrace compile options
  s390: reintroduce diag 44 calls for cpu_relax()
  s390/zcrypt: Add support for new crypto express (CEX5S) adapter.
  s390/zcrypt: Number of supported ap domains is not retrievable.
  s390/spinlock: add compare-and-delay to lock wait loops
  s390/tape: remove redundant if statement
  s390/hvc_iucv: add simple wildcard matches to the iucv allow filter
  ...
2015-02-11 17:42:32 -08:00
Kirill A. Shutemov b30fe6c7ce mm: fix false-positive warning on exit due mm_nr_pmds(mm)
The problem is that we check nr_ptes/nr_pmds in exit_mmap() which happens
*before* pgd_free().  And if an arch does pte/pmd allocation in
pgd_alloc() and frees them in pgd_free() we see offset in counters by the
time of the checks.

We tried to workaround this by offsetting expected counter value according
to FIRST_USER_ADDRESS for both nr_pte and nr_pmd in exit_mmap().  But it
doesn't work in some cases:

1. ARM with LPAE enabled also has non-zero USER_PGTABLES_CEILING, but
   upper addresses occupied with huge pmd entries, so the trick with
   offsetting expected counter value will get really ugly: we will have
   to apply it nr_pmds, but not nr_ptes.

2. Metag has non-zero FIRST_USER_ADDRESS, but doesn't do allocation
   pte/pmd page tables allocation in pgd_alloc(), just setup a pgd entry
   which is allocated at boot and shared accross all processes.

The proposal is to move the check to check_mm() which happens *after*
pgd_free() and do proper accounting during pgd_alloc() and pgd_free()
which would bring counters to zero if nothing leaked.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Tyler Baker <tyler.baker@linaro.org>
Tested-by: Tyler Baker <tyler.baker@linaro.org>
Tested-by: Nishanth Menon <nm@ti.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 17:06:04 -08:00
Kirill A. Shutemov dc6c9a35b6 mm: account pmd page tables to the process
Dave noticed that unprivileged process can allocate significant amount of
memory -- >500 MiB on x86_64 -- and stay unnoticed by oom-killer and
memory cgroup.  The trick is to allocate a lot of PMD page tables.  Linux
kernel doesn't account PMD tables to the process, only PTE.

The use-cases below use few tricks to allocate a lot of PMD page tables
while keeping VmRSS and VmPTE low.  oom_score for the process will be 0.

	#include <errno.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <unistd.h>
	#include <sys/mman.h>
	#include <sys/prctl.h>

	#define PUD_SIZE (1UL << 30)
	#define PMD_SIZE (1UL << 21)

	#define NR_PUD 130000

	int main(void)
	{
		char *addr = NULL;
		unsigned long i;

		prctl(PR_SET_THP_DISABLE);
		for (i = 0; i < NR_PUD ; i++) {
			addr = mmap(addr + PUD_SIZE, PUD_SIZE, PROT_WRITE|PROT_READ,
					MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
			if (addr == MAP_FAILED) {
				perror("mmap");
				break;
			}
			*addr = 'x';
			munmap(addr, PMD_SIZE);
			mmap(addr, PMD_SIZE, PROT_WRITE|PROT_READ,
					MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED, -1, 0);
			if (addr == MAP_FAILED)
				perror("re-mmap"), exit(1);
		}
		printf("PID %d consumed %lu KiB in PMD page tables\n",
				getpid(), i * 4096 >> 10);
		return pause();
	}

The patch addresses the issue by account PMD tables to the process the
same way we account PTE.

The main place where PMD tables is accounted is __pmd_alloc() and
free_pmd_range(). But there're few corner cases:

 - HugeTLB can share PMD page tables. The patch handles by accounting
   the table to all processes who share it.

 - x86 PAE pre-allocates few PMD tables on fork.

 - Architectures with FIRST_USER_ADDRESS > 0. We need to adjust sanity
   check on exit(2).

Accounting only happens on configuration where PMD page table's level is
present (PMD is not folded).  As with nr_ptes we use per-mm counter.  The
counter value is used to calculate baseline for badness score by
oom-killer.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: David Rientjes <rientjes@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 17:06:04 -08:00
Michal Hocko c32b3cbe0d oom, PM: make OOM detection in the freezer path raceless
Commit 5695be142e ("OOM, PM: OOM killed task shouldn't escape PM
suspend") has left a race window when OOM killer manages to
note_oom_kill after freeze_processes checks the counter.  The race
window is quite small and really unlikely and partial solution deemed
sufficient at the time of submission.

Tejun wasn't happy about this partial solution though and insisted on a
full solution.  That requires the full OOM and freezer's task freezing
exclusion, though.  This is done by this patch which introduces oom_sem
RW lock and turns oom_killer_disable() into a full OOM barrier.

oom_killer_disabled check is moved from the allocation path to the OOM
level and we take oom_sem for reading for both the check and the whole
OOM invocation.

oom_killer_disable() takes oom_sem for writing so it waits for all
currently running OOM killer invocations.  Then it disable all the further
OOMs by setting oom_killer_disabled and checks for any oom victims.
Victims are counted via mark_tsk_oom_victim resp.  unmark_oom_victim.  The
last victim wakes up all waiters enqueued by oom_killer_disable().
Therefore this function acts as the full OOM barrier.

The page fault path is covered now as well although it was assumed to be
safe before.  As per Tejun, "We used to have freezing points deep in file
system code which may be reacheable from page fault." so it would be
better and more robust to not rely on freezing points here.  Same applies
to the memcg OOM killer.

out_of_memory tells the caller whether the OOM was allowed to trigger and
the callers are supposed to handle the situation.  The page allocation
path simply fails the allocation same as before.  The page fault path will
retry the fault (more on that later) and Sysrq OOM trigger will simply
complain to the log.

Normally there wouldn't be any unfrozen user tasks after
try_to_freeze_tasks so the function will not block. But if there was an
OOM killer racing with try_to_freeze_tasks and the OOM victim didn't
finish yet then we have to wait for it. This should complete in a finite
time, though, because

	- the victim cannot loop in the page fault handler (it would die
	  on the way out from the exception)
	- it cannot loop in the page allocator because all the further
	  allocation would fail and __GFP_NOFAIL allocations are not
	  acceptable at this stage
	- it shouldn't be blocked on any locks held by frozen tasks
	  (try_to_freeze expects lockless context) and kernel threads and
	  work queues are not frozen yet

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Suggested-by: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 17:06:03 -08:00
Michal Hocko 35536ae170 PM: convert printk to pr_* equivalent
While touching this area let's convert printk to pr_*.  This also makes
the printing of continuation lines done properly.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 17:06:03 -08:00
Michal Hocko 49550b6055 oom: add helpers for setting and clearing TIF_MEMDIE
This patchset addresses a race which was described in the changelog for
5695be142e ("OOM, PM: OOM killed task shouldn't escape PM suspend"):

: PM freezer relies on having all tasks frozen by the time devices are
: getting frozen so that no task will touch them while they are getting
: frozen.  But OOM killer is allowed to kill an already frozen task in order
: to handle OOM situtation.  In order to protect from late wake ups OOM
: killer is disabled after all tasks are frozen.  This, however, still keeps
: a window open when a killed task didn't manage to die by the time
: freeze_processes finishes.

The original patch hasn't closed the race window completely because that
would require a more complex solution as it can be seen by this patchset.

The primary motivation was to close the race condition between OOM killer
and PM freezer _completely_.  As Tejun pointed out, even though the race
condition is unlikely the harder it would be to debug weird bugs deep in
the PM freezer when the debugging options are reduced considerably.  I can
only speculate what might happen when a task is still runnable
unexpectedly.

On a plus side and as a side effect the oom enable/disable has a better
(full barrier) semantic without polluting hot paths.

I have tested the series in KVM with 100M RAM:
- many small tasks (20M anon mmap) which are triggering OOM continually
- s2ram which resumes automatically is triggered in a loop
	echo processors > /sys/power/pm_test
	while true
	do
		echo mem > /sys/power/state
		sleep 1s
	done
- simple module which allocates and frees 20M in 8K chunks. If it sees
  freezing(current) then it tries another round of allocation before calling
  try_to_freeze
- debugging messages of PM stages and OOM killer enable/disable/fail added
  and unmark_oom_victim is delayed by 1s after it clears TIF_MEMDIE and before
  it wakes up waiters.
- rebased on top of the current mmotm which means some necessary updates
  in mm/oom_kill.c. mark_tsk_oom_victim is now called under task_lock but
  I think this should be OK because __thaw_task shouldn't interfere with any
  locking down wake_up_process. Oleg?

As expected there are no OOM killed tasks after oom is disabled and
allocations requested by the kernel thread are failing after all the tasks
are frozen and OOM disabled.  I wasn't able to catch a race where
oom_killer_disable would really have to wait but I kinda expected the race
is really unlikely.

[  242.609330] Killed process 2992 (mem_eater) total-vm:24412kB, anon-rss:2164kB, file-rss:4kB
[  243.628071] Unmarking 2992 OOM victim. oom_victims: 1
[  243.636072] (elapsed 2.837 seconds) done.
[  243.641985] Trying to disable OOM killer
[  243.643032] Waiting for concurent OOM victims
[  243.644342] OOM killer disabled
[  243.645447] Freezing remaining freezable tasks ... (elapsed 0.005 seconds) done.
[  243.652983] Suspending console(s) (use no_console_suspend to debug)
[  243.903299] kmem_eater: page allocation failure: order:1, mode:0x204010
[...]
[  243.992600] PM: suspend of devices complete after 336.667 msecs
[  243.993264] PM: late suspend of devices complete after 0.660 msecs
[  243.994713] PM: noirq suspend of devices complete after 1.446 msecs
[  243.994717] ACPI: Preparing to enter system sleep state S3
[  243.994795] PM: Saving platform NVS memory
[  243.994796] Disabling non-boot CPUs ...

The first 2 patches are simple cleanups for OOM.  They should go in
regardless the rest IMO.

Patches 3 and 4 are trivial printk -> pr_info conversion and they should
go in ditto.

The main patch is the last one and I would appreciate acks from Tejun and
Rafael.  I think the OOM part should be OK (except for __thaw_task vs.
task_lock where a look from Oleg would appreciated) but I am not so sure I
haven't screwed anything in the freezer code.  I have found several
surprises there.

This patch (of 5):

This patch is just a preparatory and it doesn't introduce any functional
change.

Note:
I am utterly unhappy about lowmemory killer abusing TIF_MEMDIE just to
wait for the oom victim and to prevent from new killing. This is
just a side effect of the flag. The primary meaning is to give the oom
victim access to the memory reserves and that shouldn't be necessary
here.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-11 17:06:03 -08:00
Paul E. McKenney c0135d07b0 rcu: Clear need_qs flag to prevent splat
If the scheduling-clock interrupt sets the current tasks need_qs flag,
but if the current CPU passes through a quiescent state in the meantime,
then rcu_preempt_qs() will fail to clear the need_qs flag, which can fool
RCU into thinking that additional rcu_read_unlock_special() processing
is needed.  This commit therefore clears the need_qs flag before checking
for additional processing.

For this problem to occur, we need rcu_preempt_data.passed_quiesce equal
to true and current->rcu_read_unlock_special.b.need_qs also equal to true.
This condition can occur as follows:

1.	CPU 0 is aware of the current preemptible RCU grace period,
	but has not yet passed through a quiescent state.  Among other
	things, this means that rcu_preempt_data.passed_quiesce is false.

2.	Task A running on CPU 0 enters a preemptible RCU read-side
	critical section.

3.	CPU 0 takes a scheduling-clock interrupt, which notices the
	RCU read-side critical section and the need for a quiescent state,
	and thus sets current->rcu_read_unlock_special.b.need_qs to true.

4.	Task A is preempted, enters the scheduler, eventually invoking
	rcu_preempt_note_context_switch() which in turn invokes
	rcu_preempt_qs().

	Because rcu_preempt_data.passed_quiesce is false,
	control enters the body of the "if" statement, which sets
	rcu_preempt_data.passed_quiesce to true.

5.	At this point, CPU 0 takes an interrupt.  The interrupt
	handler contains an RCU read-side critical section, and
	the rcu_read_unlock() notes that current->rcu_read_unlock_special
	is nonzero, and thus invokes rcu_read_unlock_special().

6.	Once in rcu_read_unlock_special(), the fact that
	current->rcu_read_unlock_special.b.need_qs is true becomes
	apparent, so rcu_read_unlock_special() invokes rcu_preempt_qs().
	Recursively, given that we interrupted out of that same
	function in the preceding step.

7.	Because rcu_preempt_data.passed_quiesce is now true,
	rcu_preempt_qs() does nothing, and simply returns.

8.	Upon return to rcu_read_unlock_special(), it is noted that
	current->rcu_read_unlock_special is still nonzero (because
	the interrupted rcu_preempt_qs() had not yet gotten around
	to clearing current->rcu_read_unlock_special.b.need_qs).

9.	Execution proceeds to the WARN_ON_ONCE(), which notes that
	we are in an interrupt handler and thus duly splats.

The solution, as noted above, is to make rcu_read_unlock_special()
clear out current->rcu_read_unlock_special.b.need_qs after calling
rcu_preempt_qs().  The interrupted rcu_preempt_qs() will clear it again,
but this is harmless.  The worst that happens is that we clobber another
attempt to set this field, but this is not a problem because we just
got done reporting a quiescent state.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Fix embarrassing build bug noted by Sasha Levin. ]
Tested-by: Sasha Levin <sasha.levin@oracle.com>
2015-02-11 15:46:43 -08:00
Steven Rostedt (Red Hat) 1e0d6714ac ring-buffer: Do not wake up a splice waiter when page is not full
When an application connects to the ring buffer via splice, it can only
read full pages. Splice does not work with partial pages. If there is
not enough data to fill a page, the splice command will either block
or return -EAGAIN (if set to nonblock).

Code was added where if the page is not full, to just sleep again.
The problem is, it will get woken up again on the next event. That
is, when something is written into the ring buffer, if there is a waiter
it will wake it up. The waiter would then check the buffer, see that
it still does not have enough data to fill a page and go back to sleep.
To make matters worse, when the waiter goes back to sleep, it could
cause another event, which would wake it back up again to see it
doesn't have enough data and sleep again. This produces a tremendous
overhead and fills the ring buffer with noise.

For example, recording sched_switch on an idle system for 10 seconds
produces 25,350,475 events!!!

Create another wait queue for those waiters wanting full pages.
When an event is written, it only wakes up waiters if there's a full
page of data. It does not wake up the waiter if the page is not yet
full.

After this change, recording sched_switch on an idle system for 10
seconds produces only 800 events. Getting rid of 25,349,675 useless
events (99.9969% of events!!), is something to take seriously.

Cc: stable@vger.kernel.org # 3.16+
Cc: Rabin Vincent <rabin@rab.in>
Fixes: e30f53aad2 "tracing: Do not busy wait in buffer splice"
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-02-11 07:41:42 -05:00
Peter Zijlstra 9cc019b8c9 module: Replace over-engineered nested sleep
Since the introduction of the nested sleep warning; we've established
that the occasional sleep inside a wait_event() is fine.

wait_event() loops are invariant wrt. spurious wakeups, and the
occasional sleep has a similar effect on them. As long as its occasional
its harmless.

Therefore replace the 'correct' but verbose wait_woken() thing with
a simple annotation to shut up the warning.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-11 15:02:04 +10:30
Peter Zijlstra d64810f561 module: Annotate nested sleep in resolve_symbol()
Because wait_event() loops are safe vs spurious wakeups we can allow the
occasional sleep -- which ends up being very similar.

Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-11 15:02:04 +10:30
Linus Torvalds c5ce28df0e Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) More iov_iter conversion work from Al Viro.

    [ The "crypto: switch af_alg_make_sg() to iov_iter" commit was
      wrong, and this pull actually adds an extra commit on top of the
      branch I'm pulling to fix that up, so that the pre-merge state is
      ok.   - Linus ]

 2) Various optimizations to the ipv4 forwarding information base trie
    lookup implementation.  From Alexander Duyck.

 3) Remove sock_iocb altogether, from CHristoph Hellwig.

 4) Allow congestion control algorithm selection via routing metrics.
    From Daniel Borkmann.

 5) Make ipv4 uncached route list per-cpu, from Eric Dumazet.

 6) Handle rfs hash collisions more gracefully, also from Eric Dumazet.

 7) Add xmit_more support to r8169, e1000, and e1000e drivers.  From
    Florian Westphal.

 8) Transparent Ethernet Bridging support for GRO, from Jesse Gross.

 9) Add BPF packet actions to packet scheduler, from Jiri Pirko.

10) Add support for uniqu flow IDs to openvswitch, from Joe Stringer.

11) New NetCP ethernet driver, from Muralidharan Karicheri and Wingman
    Kwok.

12) More sanely handle out-of-window dupacks, which can result in
    serious ACK storms.  From Neal Cardwell.

13) Various rhashtable bug fixes and enhancements, from Herbert Xu,
    Patrick McHardy, and Thomas Graf.

14) Support xmit_more in be2net, from Sathya Perla.

15) Group Policy extensions for vxlan, from Thomas Graf.

16) Remove Checksum Offload support for vxlan, from Tom Herbert.

17) Like ipv4, support lockless transmit over ipv6 UDP sockets.  From
    Vlad Yasevich.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1494+1 commits)
  crypto: fix af_alg_make_sg() conversion to iov_iter
  ipv4: Namespecify TCP PMTU mechanism
  i40e: Fix for stats init function call in Rx setup
  tcp: don't include Fast Open option in SYN-ACK on pure SYN-data
  openvswitch: Only set TUNNEL_VXLAN_OPT if VXLAN-GBP metadata is set
  ipv6: Make __ipv6_select_ident static
  ipv6: Fix fragment id assignment on LE arches.
  bridge: Fix inability to add non-vlan fdb entry
  net: Mellanox: Delete unnecessary checks before the function call "vunmap"
  cxgb4: Add support in cxgb4 to get expansion rom version via ethtool
  ethtool: rename reserved1 memeber in ethtool_drvinfo for expansion ROM version
  net: dsa: Remove redundant phy_attach()
  IB/mlx4: Reset flow support for IB kernel ULPs
  IB/mlx4: Always use the correct port for mirrored multicast attachments
  net/bonding: Fix potential bad memory access during bonding events
  tipc: remove tipc_snprintf
  tipc: nl compat add noop and remove legacy nl framework
  tipc: convert legacy nl stats show to nl compat
  tipc: convert legacy nl net id get to nl compat
  tipc: convert legacy nl net id set to nl compat
  ...
2015-02-10 20:01:30 -08:00
Linus Torvalds 29afc4e9a4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree changes from Jiri Kosina:
 "Patches from trivial.git that keep the world turning around.

  Mostly documentation and comment fixes, and a two corner-case code
  fixes from Alan Cox"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  kexec, Kconfig: spell "architecture" properly
  mm: fix cleancache debugfs directory path
  blackfin: mach-common: ints-priority: remove unused function
  doubletalk: probe failure causes OOPS
  ARM: cache-l2x0.c: Make it clear that cache-l2x0 handles L310 cache controller
  msdos_fs.h: fix 'fields' in comment
  scsi: aic7xxx: fix comment
  ARM: l2c: fix comment
  ibmraid: fix writeable attribute with no store method
  dynamic_debug: fix comment
  doc: usbmon: fix spelling s/unpriviledged/unprivileged/
  x86: init_mem_mapping(): use capital BIOS in comment
2015-02-10 18:57:15 -08:00
Linus Torvalds 1d9c5d79e6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull live patching infrastructure from Jiri Kosina:
 "Let me provide a bit of history first, before describing what is in
  this pile.

  Originally, there was kSplice as a standalone project that implemented
  stop_machine()-based patching for the linux kernel.  This project got
  later acquired, and the current owner is providing live patching as a
  proprietary service, without any intentions to have their
  implementation merged.

  Then, due to rising user/customer demand, both Red Hat and SUSE
  started working on their own implementation (not knowing about each
  other), and announced first versions roughly at the same time [1] [2].

  The principle difference between the two solutions is how they are
  making sure that the patching is performed in a consistent way when it
  comes to different execution threads with respect to the semantic
  nature of the change that is being introduced.

  In a nutshell, kPatch is issuing stop_machine(), then looking at
  stacks of all existing processess, and if it decides that the system
  is in a state that can be patched safely, it proceeds insterting code
  redirection machinery to the patched functions.

  On the other hand, kGraft provides a per-thread consistency during one
  single pass of a process through the kernel and performs a lazy
  contignuous migration of threads from "unpatched" universe to the
  "patched" one at safe checkpoints.

  If interested in a more detailed discussion about the consistency
  models and its possible combinations, please see the thread that
  evolved around [3].

  It pretty quickly became obvious to the interested parties that it's
  absolutely impractical in this case to have several isolated solutions
  for one task to co-exist in the kernel.  During a dedicated Live
  Kernel Patching track at LPC in Dusseldorf, all the interested parties
  sat together and came up with a joint aproach that would work for both
  distro vendors.  Steven Rostedt took notes [4] from this meeting.

  And the foundation for that aproach is what's present in this pull
  request.

  It provides a basic infrastructure for function "live patching" (i.e.
  code redirection), including API for kernel modules containing the
  actual patches, and API/ABI for userspace to be able to operate on the
  patches (look up what patches are applied, enable/disable them, etc).

  It's relatively simple and minimalistic, as it's making use of
  existing kernel infrastructure (namely ftrace) as much as possible.
  It's also self-contained, in a sense that it doesn't hook itself in
  any other kernel subsystem (it doesn't even touch any other code).
  It's now implemented for x86 only as a reference architecture, but
  support for powerpc, s390 and arm is already in the works (adding
  arch-specific support basically boils down to teaching ftrace about
  regs-saving).

  Once this common infrastructure gets merged, both Red Hat and SUSE
  have agreed to immediately start porting their current solutions on
  top of this, abandoning their out-of-tree code.  The plan basically is
  that each patch will be marked by flag(s) that would indicate which
  consistency model it is willing to use (again, the details have been
  sketched out already in the thread at [3]).

  Before this happens, the current codebase can be used to patch a large
  group of secruity/stability problems the patches for which are not too
  complex (in a sense that they don't introduce non-trivial change of
  function's return value semantics, they don't change layout of data
  structures, etc) -- this corresponds to LEAVE_FUNCTION &&
  SWITCH_FUNCTION semantics described at [3].

  This tree has been in linux-next since December.

    [1] https://lkml.org/lkml/2014/4/30/477
    [2] https://lkml.org/lkml/2014/7/14/857
    [3] https://lkml.org/lkml/2014/11/7/354
    [4] http://linuxplumbersconf.org/2014/wp-content/uploads/2014/10/LPC2014_LivePatching.txt

  [ The core code is introduced by the three commits authored by Seth
    Jennings, which got a lot of changes incorporated during numerous
    respins and reviews of the initial implementation.  All the followup
    commits have materialized only after public tree has been created,
    so they were not folded into initial three commits so that the
    public tree doesn't get rebased ]"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: add missing newline to error message
  livepatch: rename config to CONFIG_LIVEPATCH
  livepatch: fix uninitialized return value
  livepatch: support for repatching a function
  livepatch: enforce patch stacking semantics
  livepatch: change ARCH_HAVE_LIVE_PATCHING to HAVE_LIVE_PATCHING
  livepatch: fix deferred module patching order
  livepatch: handle ancient compilers with more grace
  livepatch: kconfig: use bool instead of boolean
  livepatch: samples: fix usage example comments
  livepatch: MAINTAINERS: add git tree location
  livepatch: use FTRACE_OPS_FL_IPMODIFY
  livepatch: move x86 specific ftrace handler code to arch/x86
  livepatch: samples: add sample live patching module
  livepatch: kernel: add support for live patching
  livepatch: kernel: add TAINT_LIVEPATCH
2015-02-10 18:35:40 -08:00
Linus Torvalds 992de5a8ec Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "Bite-sized chunks this time, to avoid the MTA ratelimiting woes.

   - fs/notify updates

   - ocfs2

   - some of MM"

That laconic "some MM" is mainly the removal of remap_file_pages(),
which is a big simplification of the VM, and which gets rid of a *lot*
of random cruft and special cases because we no longer support the
non-linear mappings that it used.

From a user interface perspective, nothing has changed, because the
remap_file_pages() syscall still exists, it's just done by emulating the
old behavior by creating a lot of individual small mappings instead of
one non-linear one.

The emulation is slower than the old "native" non-linear mappings, but
nobody really uses or cares about remap_file_pages(), and simplifying
the VM is a big advantage.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (78 commits)
  memcg: zap memcg_slab_caches and memcg_slab_mutex
  memcg: zap memcg_name argument of memcg_create_kmem_cache
  memcg: zap __memcg_{charge,uncharge}_slab
  mm/page_alloc.c: place zone_id check before VM_BUG_ON_PAGE check
  mm: hugetlb: fix type of hugetlb_treat_as_movable variable
  mm, hugetlb: remove unnecessary lower bound on sysctl handlers"?
  mm: memory: merge shared-writable dirtying branches in do_wp_page()
  mm: memory: remove ->vm_file check on shared writable vmas
  xtensa: drop _PAGE_FILE and pte_file()-related helpers
  x86: drop _PAGE_FILE and pte_file()-related helpers
  unicore32: drop pte_file()-related helpers
  um: drop _PAGE_FILE and pte_file()-related helpers
  tile: drop pte_file()-related helpers
  sparc: drop pte_file()-related helpers
  sh: drop _PAGE_FILE and pte_file()-related helpers
  score: drop _PAGE_FILE and pte_file()-related helpers
  s390: drop pte_file()-related helpers
  parisc: drop _PAGE_FILE and pte_file()-related helpers
  openrisc: drop _PAGE_FILE and pte_file()-related helpers
  nios2: drop _PAGE_FILE and pte_file()-related helpers
  ...
2015-02-10 16:45:56 -08:00
Linus Torvalds 872912352c ACPI and power management updates for v3.20-rc1
- Rework of the core ACPI resources parsing code to fix issues
    in it and make using resource offsets more convenient and
    consolidation of some resource-handing code in a couple of places
    that have grown analagous data structures and code to cover the
    the same gap in the core (Jiang Liu, Thomas Gleixner, Lv Zheng).
 
  - ACPI-based IOAPIC hotplug support on top of the resources handling
    rework (Jiang Liu, Yinghai Lu).
 
  - ACPICA update to upstream release 20150204 including an interrupt
    handling rework that allows drivers to install raw handlers for
    ACPI GPEs which then become entirely responsible for the given GPE
    and the ACPICA core code won't touch it (Lv Zheng, David E Box,
    Octavian Purdila).
 
  - ACPI EC driver rework to fix several concurrency issues and other
    problems related to events handling on top of the ACPICA's new
    support for raw GPE handlers (Lv Zheng).
 
  - New ACPI driver for AMD SoCs analogous to the LPSS (Low-Power
    Subsystem) driver for Intel chips (Ken Xue).
 
  - Two minor fixes of the ACPI LPSS driver (Heikki Krogerus,
    Jarkko Nikula).
 
  - Two new blacklist entries for machines (Samsung 730U3E/740U3E and
    510R) where the native backlight interface doesn't work correctly
    while the ACPI one does (Hans de Goede).
 
  - Rework of the ACPI processor driver's handling of idle states
    to make the code more straightforward and less bloated overall
    (Rafael J Wysocki).
 
  - Assorted minor fixes related to ACPI and SFI (Andreas Ruprecht,
    Andy Shevchenko, Hanjun Guo, Jan Beulich, Rafael J Wysocki,
    Yaowei Bai).
 
  - PCI core power management modification to avoid resuming (some)
    runtime-suspended devices during system suspend if they are in
    the right states already (Rafael J Wysocki).
 
  - New SFI-based cpufreq driver for Intel platforms using SFI
    (Srinidhi Kasagar).
 
  - cpufreq core fixes, cleanups and simplifications (Viresh Kumar,
    Doug Anderson, Wolfram Sang).
 
  - SkyLake CPU support and other updates for the intel_pstate driver
    (Kristen Carlson Accardi, Srinivas Pandruvada).
 
  - cpufreq-dt driver cleanup (Markus Elfring).
 
  - Init fix for the ARM big.LITTLE cpuidle driver (Sudeep Holla).
 
  - Generic power domains core code fixes and cleanups (Ulf Hansson).
 
  - Operating Performance Points (OPP) core code cleanups and kernel
    documentation update (Nishanth Menon).
 
  - New dabugfs interface to make the list of PM QoS constraints
    available to user space (Nishanth Menon).
 
  - New devfreq driver for Tegra Activity Monitor (Tomeu Vizoso).
 
  - New devfreq class (devfreq_event) to provide raw utilization data
    to devfreq governors (Chanwoo Choi).
 
  - Assorted minor fixes and cleanups related to power management
    (Andreas Ruprecht, Krzysztof Kozlowski, Rickard Strandqvist,
    Pavel Machek, Todd E Brandt, Wonhong Kwon).
 
  - turbostat updates (Len Brown) and cpupower Makefile improvement
    (Sriram Raghunathan).
 
 /
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Merge tag 'pm+acpi-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management updates from Rafael Wysocki:
 "We have a few new features this time, including a new SFI-based
  cpufreq driver, a new devfreq driver for Tegra Activity Monitor, a new
  devfreq class for providing its governors with raw utilization data
  and a new ACPI driver for AMD SoCs.

  Still, the majority of changes here are reworks of existing code to
  make it more straightforward or to prepare it for implementing new
  features on top of it.  The primary example is the rework of ACPI
  resources handling from Jiang Liu, Thomas Gleixner and Lv Zheng with
  support for IOAPIC hotplug implemented on top of it, but there is
  quite a number of changes of this kind in the cpufreq core, ACPICA,
  ACPI EC driver, ACPI processor driver and the generic power domains
  core code too.

  The most active developer is Viresh Kumar with his cpufreq changes.

  Specifics:

   - Rework of the core ACPI resources parsing code to fix issues in it
     and make using resource offsets more convenient and consolidation
     of some resource-handing code in a couple of places that have grown
     analagous data structures and code to cover the the same gap in the
     core (Jiang Liu, Thomas Gleixner, Lv Zheng).

   - ACPI-based IOAPIC hotplug support on top of the resources handling
     rework (Jiang Liu, Yinghai Lu).

   - ACPICA update to upstream release 20150204 including an interrupt
     handling rework that allows drivers to install raw handlers for
     ACPI GPEs which then become entirely responsible for the given GPE
     and the ACPICA core code won't touch it (Lv Zheng, David E Box,
     Octavian Purdila).

   - ACPI EC driver rework to fix several concurrency issues and other
     problems related to events handling on top of the ACPICA's new
     support for raw GPE handlers (Lv Zheng).

   - New ACPI driver for AMD SoCs analogous to the LPSS (Low-Power
     Subsystem) driver for Intel chips (Ken Xue).

   - Two minor fixes of the ACPI LPSS driver (Heikki Krogerus, Jarkko
     Nikula).

   - Two new blacklist entries for machines (Samsung 730U3E/740U3E and
     510R) where the native backlight interface doesn't work correctly
     while the ACPI one does (Hans de Goede).

   - Rework of the ACPI processor driver's handling of idle states to
     make the code more straightforward and less bloated overall (Rafael
     J Wysocki).

   - Assorted minor fixes related to ACPI and SFI (Andreas Ruprecht,
     Andy Shevchenko, Hanjun Guo, Jan Beulich, Rafael J Wysocki, Yaowei
     Bai).

   - PCI core power management modification to avoid resuming (some)
     runtime-suspended devices during system suspend if they are in the
     right states already (Rafael J Wysocki).

   - New SFI-based cpufreq driver for Intel platforms using SFI
     (Srinidhi Kasagar).

   - cpufreq core fixes, cleanups and simplifications (Viresh Kumar,
     Doug Anderson, Wolfram Sang).

   - SkyLake CPU support and other updates for the intel_pstate driver
     (Kristen Carlson Accardi, Srinivas Pandruvada).

   - cpufreq-dt driver cleanup (Markus Elfring).

   - Init fix for the ARM big.LITTLE cpuidle driver (Sudeep Holla).

   - Generic power domains core code fixes and cleanups (Ulf Hansson).

   - Operating Performance Points (OPP) core code cleanups and kernel
     documentation update (Nishanth Menon).

   - New dabugfs interface to make the list of PM QoS constraints
     available to user space (Nishanth Menon).

   - New devfreq driver for Tegra Activity Monitor (Tomeu Vizoso).

   - New devfreq class (devfreq_event) to provide raw utilization data
     to devfreq governors (Chanwoo Choi).

   - Assorted minor fixes and cleanups related to power management
     (Andreas Ruprecht, Krzysztof Kozlowski, Rickard Strandqvist, Pavel
     Machek, Todd E Brandt, Wonhong Kwon).

   - turbostat updates (Len Brown) and cpupower Makefile improvement
     (Sriram Raghunathan)"

* tag 'pm+acpi-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (151 commits)
  tools/power turbostat: relax dependency on APERF_MSR
  tools/power turbostat: relax dependency on invariant TSC
  Merge branch 'pci/host-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci into acpi-resources
  tools/power turbostat: decode MSR_*_PERF_LIMIT_REASONS
  tools/power turbostat: relax dependency on root permission
  ACPI / video: Add disable_native_backlight quirk for Samsung 510R
  ACPI / PM: Remove unneeded nested #ifdef
  USB / PM: Remove unneeded #ifdef and associated dead code
  intel_pstate: provide option to only use intel_pstate with HWP
  ACPI / EC: Add GPE reference counting debugging messages
  ACPI / EC: Add query flushing support
  ACPI / EC: Refine command storm prevention support
  ACPI / EC: Add command flushing support.
  ACPI / EC: Introduce STARTED/STOPPED flags to replace BLOCKED flag
  ACPI: add AMD ACPI2Platform device support for x86 system
  ACPI / table: remove duplicate NULL check for the handler of acpi_table_parse()
  ACPI / EC: Update revision due to raw handler mode.
  ACPI / EC: Reduce ec_poll() by referencing the last register access timestamp.
  ACPI / EC: Fix several GPE handling issues by deploying ACPI_GPE_DISPATCH_RAW_HANDLER mode.
  ACPICA: Events: Enable APIs to allow interrupt/polling adaptive request based GPE handling model
  ...
2015-02-10 15:09:41 -08:00
Andrey Ryabinin 3cd7645de6 mm, hugetlb: remove unnecessary lower bound on sysctl handlers"?
Commit ed4d4902eb ("mm, hugetlb: remove hugetlb_zero and
hugetlb_infinity") replaced 'unsigned long hugetlb_zero' with 'int zero'
leading to out-of-bounds access in proc_doulongvec_minmax().  Use
'.extra1 = NULL' instead of '.extra1 = &zero'.  Passing NULL is
equivalent to passing minimal value, which is 0 for unsigned types.

Fixes: ed4d4902eb ("mm, hugetlb: remove hugetlb_zero and hugetlb_infinity")
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Suggested-by: Manfred Spraul <manfred@colorfullife.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>
2015-02-10 14:30:34 -08:00
Kirill A. Shutemov 27ba0644ea rmap: drop support of non-linear mappings
We don't create non-linear mappings anymore.  Let's drop code which
handles them in rmap.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-10 14:30:31 -08:00
Rafael J. Wysocki f52386892f Merge branches 'pm-sleep' and 'pm-runtime'
* pm-sleep:
  PM / hibernate: exclude freed pages from allocated pages printout
  PM / sleep: export suspend_resume trace event
  PM / sleep: Mention async suspend in PM_TRACE documentation
  PM / hibernate: Remove unused function

* pm-runtime:
  ACPI / PM: Remove unneeded nested #ifdef
  USB / PM: Remove unneeded #ifdef and associated dead code
2015-02-10 16:09:52 +01:00
Rafael J. Wysocki 740b68ea3a Merge branches 'pm-qos', 'pm-opp' and 'pm-devfreq'
* pm-qos:
  PM / QoS: Use lockdep asserts to find missing hold of power.lock
  PM / QoS: Add debugfs support to view the list of constraints

* pm-opp:
  PM / OPP: Assert RCU lock in exported functions
  PM / OPP: Update kernel documentation
  PM / OPP: Ensure consistent naming of static functions
  PM / OPP: export dev_pm_opp_get_notifier

* pm-devfreq:
  PM / devfreq: event: Add documentation for exynos-ppmu devfreq-event driver
  devfreq: Fix build break of devfreq-event class
  PM / devfreq: event: Add devfreq_event class
  PM / devfreq: tegra: add devfreq driver for Tegra Activity Monitor
2015-02-10 16:09:34 +01:00
Rafael J. Wysocki 8fbcf5ecb3 Merge branch 'acpi-resources'
* acpi-resources: (23 commits)
  Merge branch 'pci/host-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci into acpi-resources
  x86/irq, ACPI: Implement ACPI driver to support IOAPIC hotplug
  ACPI: Add interfaces to parse IOAPIC ID for IOAPIC hotplug
  x86/PCI: Refine the way to release PCI IRQ resources
  x86/PCI/ACPI: Use common ACPI resource interfaces to simplify implementation
  x86/PCI: Fix the range check for IO resources
  PCI: Use common resource list management code instead of private implementation
  resources: Move struct resource_list_entry from ACPI into resource core
  ACPI: Introduce helper function acpi_dev_filter_resource_type()
  ACPI: Add field offset to struct resource_list_entry
  ACPI: Translate resource into master side address for bridge window resources
  ACPI: Return translation offset when parsing ACPI address space resources
  ACPI: Enforce stricter checks for address space descriptors
  ACPI: Set flag IORESOURCE_UNSET for unassigned resources
  ACPI: Normalize return value of resource parser functions
  ACPI: Fix a bug in parsing ACPI Memory24 resource
  ACPI: Add prefetch decoding to the address space parser
  ACPI: Move the window flag logic to the combined parser
  ACPI: Unify the parsing of address_space and ext_address_space
  ACPI: Let the parser return false for disabled resources
  ...
2015-02-10 16:05:16 +01:00
Linus Torvalds 0ba97bc4b4 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Ingo Molnar:
 "The main changes in this cycle were:

   - rework hrtimer expiry calculation in hrtimer_interrupt(): the
     previous code had a subtle bug where expiry caching would miss an
     expiry, resulting in occasional bogus (late) expiry of hrtimers.

   - continuing Y2038 fixes

   - ktime division optimization

   - misc smaller fixes and cleanups"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Make __hrtimer_get_next_event() static
  rtc: Convert rtc_set_ntp_time() to use timespec64
  rtc: Remove redundant rtc_valid_tm() from rtc_hctosys()
  rtc: Modify rtc_hctosys() to address y2038 issues
  rtc: Update rtc-dev to use y2038-safe time interfaces
  rtc: Update interface.c to use y2038-safe time interfaces
  time: Expose get_monotonic_boottime64 for in-kernel use
  time: Expose getboottime64 for in-kernel uses
  ktime: Optimize ktime_divns for constant divisors
  hrtimer: Prevent stale expiry time in hrtimer_interrupt()
  ktime.h: Introduce ktime_ms_delta
2015-02-09 16:33:07 -08:00
Linus Torvalds 5b9b28a63f Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main scheduler changes in this cycle were:

   - various sched/deadline fixes and enhancements

   - rescheduling latency fixes/cleanups

   - rework the rq->clock code to be more consistent and more robust.

   - minor micro-optimizations

   - ->avg.decay_count fixes

   - add a stack overflow check to might_sleep()

   - idle-poll handler fix, possibly resulting in power savings

   - misc smaller updates and fixes"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/Documentation: Remove unneeded word
  sched/wait: Introduce wait_on_bit_timeout()
  sched: Pull resched loop to __schedule() callers
  sched/deadline: Remove cpu_active_mask from cpudl_find()
  sched: Fix hrtick_start() on UP
  sched/deadline: Avoid pointless __setscheduler()
  sched/deadline: Fix stale yield state
  sched/deadline: Fix hrtick for a non-leftmost task
  sched/deadline: Modify cpudl::free_cpus to reflect rd->online
  sched/idle: Add missing checks to the exit condition of cpu_idle_poll()
  sched: Fix missing preemption opportunity
  sched/rt: Reduce rq lock contention by eliminating locking of non-feasible target
  sched/debug: Print rq->clock_task
  sched/core: Rework rq->clock update skips
  sched/core: Validate rq_clock*() serialization
  sched/core: Remove check of p->sched_class
  sched/fair: Fix sched_entity::avg::decay_count initialization
  sched/debug: Fix potential call to __ffs(0) in sched_show_task()
  sched/debug: Check for stack overflow in ___might_sleep()
  sched/fair: Fix the dealing with decay_count in __synchronize_entity_decay()
2015-02-09 16:06:06 -08:00
Vikram Mulukutla 7215853e98 tracing: Fix unmapping loop in tracing_mark_write
Commit 6edb2a8a38 introduced
an array map_pages that contains the addresses returned by
kmap_atomic. However, when unmapping those pages, map_pages[0]
is unmapped before map_pages[1], breaking the nesting requirement
as specified in the documentation for kmap_atomic/kunmap_atomic.

This was caught by the highmem debug code present in kunmap_atomic.
Fix the loop to do the unmapping properly.

Link: http://lkml.kernel.org/r/1418871056-6614-1-git-send-email-markivx@codeaurora.org

Cc: stable@vger.kernel.org # 3.5+
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Reported-by: Lime Yang <limey@codeaurora.org>
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-02-09 18:47:09 -05:00
Linus Torvalds a4cbbf549a Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Kernel side changes:

   - AMD range breakpoints support:

     Extend breakpoint tools and core to support address range through
     perf event with initial backend support for AMD extended
     breakpoints.

     The syntax is:

         perf record -e mem:addr/len:type

     For example set write breakpoint from 0x1000 to 0x1200 (0x1000 + 512)

         perf record -e mem:0x1000/512:w

   - event throttling/rotating fixes

   - various event group handling fixes, cleanups and general paranoia
     code to be more robust against bugs in the future.

    - kernel stack overhead fixes

  User-visible tooling side changes:

   - Show precise number of samples in at the end of a 'record' session,
     if processing build ids, since we will then traverse the whole
     perf.data file and see all the PERF_RECORD_SAMPLE records,
     otherwise stop showing the previous off-base heuristicly counted
     number of "samples" (Namhyung Kim).

   - Support to read compressed module from build-id cache (Namhyung
     Kim)

   - Enable sampling loads and stores simultaneously in 'perf mem'
     (Stephane Eranian)

   - 'perf diff' output improvements (Namhyung Kim)

   - Fix error reporting for evsel pgfault constructor (Arnaldo Carvalho
     de Melo)

  Tooling side infrastructure changes:

   - Cache eh/debug frame offset for dwarf unwind (Namhyung Kim)

   - Support parsing parameterized events (Cody P Schafer)

   - Add support for IP address formats in libtraceevent (David Ahern)

  Plus other misc fixes"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
  perf: Decouple unthrottling and rotating
  perf: Drop module reference on event init failure
  perf: Use POLLIN instead of POLL_IN for perf poll data in flag
  perf: Fix put_event() ctx lock
  perf: Fix move_group() order
  perf: Fix event->ctx locking
  perf: Add a bit of paranoia
  perf symbols: Convert lseek + read to pread
  perf tools: Use perf_data_file__fd() consistently
  perf symbols: Support to read compressed module from build-id cache
  perf evsel: Set attr.task bit for a tracking event
  perf header: Set header version correctly
  perf record: Show precise number of samples
  perf tools: Do not use __perf_session__process_events() directly
  perf callchain: Cache eh/debug frame offset for dwarf unwind
  perf tools: Provide stub for missing pthread_attr_setaffinity_np
  perf evsel: Don't rely on malloc working for sz 0
  tools lib traceevent: Add support for IP address formats
  perf ui/tui: Show fatal error message only if exists
  perf tests: Fix typo in sample-parsing.c
  ...
2015-02-09 15:43:55 -08:00
Linus Torvalds 8308756f45 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core locking updates from Ingo Molnar:
 "The main changes are:

   - mutex, completions and rtmutex micro-optimizations
   - lock debugging fix
   - various cleanups in the MCS and the futex code"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rtmutex: Optimize setting task running after being blocked
  locking/rwsem: Use task->state helpers
  sched/completion: Add lock-free checking of the blocking case
  sched/completion: Remove unnecessary ->wait.lock serialization when reading completion state
  locking/mutex: Explicitly mark task as running after wakeup
  futex: Fix argument handling in futex_lock_pi() calls
  doc: Fix misnamed FUTEX_CMP_REQUEUE_PI op constants
  locking/Documentation: Update code path
  softirq/preempt: Add missing current->preempt_disable_ip update
  locking/osq: No need for load/acquire when acquire-polling
  locking/mcs: Better differentiate between MCS variants
  locking/mutex: Introduce ww_mutex_set_context_slowpath()
  locking/mutex: Move MCS related comments to proper location
  locking/mutex: Checking the stamp is WW only
2015-02-09 15:24:03 -08:00
Linus Torvalds 23e8fe2e16 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main RCU changes in this cycle are:

   - Documentation updates.

   - Miscellaneous fixes.

   - Preemptible-RCU fixes, including fixing an old bug in the
     interaction of RCU priority boosting and CPU hotplug.

   - SRCU updates.

   - RCU CPU stall-warning updates.

   - RCU torture-test updates"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  rcu: Initialize tiny RCU stall-warning timeouts at boot
  rcu: Fix RCU CPU stall detection in tiny implementation
  rcu: Add GP-kthread-starvation checks to CPU stall warnings
  rcu: Make cond_resched_rcu_qs() apply to normal RCU flavors
  rcu: Optionally run grace-period kthreads at real-time priority
  ksoftirqd: Use new cond_resched_rcu_qs() function
  ksoftirqd: Enable IRQs and call cond_resched() before poking RCU
  rcutorture: Add more diagnostics in rcu_barrier() test failure case
  torture: Flag console.log file to prevent holdovers from earlier runs
  torture: Add "-enable-kvm -soundhw pcspk" to qemu command line
  rcutorture: Handle different mpstat versions
  rcutorture: Check from beginning to end of grace period
  rcu: Remove redundant rcu_batches_completed() declaration
  rcutorture: Drop rcu_torture_completed() and friends
  rcu: Provide rcu_batches_completed_sched() for TINY_RCU
  rcutorture: Use unsigned for Reader Batch computations
  rcutorture: Make build-output parsing correctly flag RCU's warnings
  rcu: Make _batches_completed() functions return unsigned long
  rcutorture: Issue warnings on close calls due to Reader Batch blows
  documentation: Fix smp typo in memory-barriers.txt
  ...
2015-02-09 14:28:42 -08:00
Jesse Brandeburg 4fe7ffb7e1 genirq: Fix null pointer reference in irq_set_affinity_hint()
The recent set_affinity commit by me introduced some null
pointer dereferences on driver unload, because some drivers
call this function with a NULL argument. This fixes the issue
by just checking for null before setting the affinity mask.

Fixes: e2e64a9325 ("genirq: Set initial affinity in irq_set_affinity_hint()")
Reported-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
CC: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20150128185739.9689.84588.stgit@jbrandeb-cp2.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-09 18:47:42 +01:00
Linus Torvalds 26cdd1f76a Merge branches 'timers-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer and x86 fix from Ingo Molnar:
 "A CLOCK_TAI early expiry fix and an x86 microcode driver oops fix"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Fix incorrect tai offset calculation for non high-res timer systems

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, microcode: Return error from driver init code when loader is disabled
2015-02-06 13:56:02 -08:00
Linus Torvalds 396e9099ea Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Misc fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/deadline: Fix deadline parameter modification handling
  sched/wait: Remove might_sleep() from wait_event_cmd()
  sched: Fix crash if cpuset_cpumask_can_shrink() is passed an empty cpumask
  sched/fair: Avoid using uninitialized variable in preferred_group_nid()
2015-02-06 13:34:26 -08:00
Linus Torvalds 29f12c48df Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core kernel fixes from Ingo Molnar:
 "Two liblockdep fixes and a CPU hotplug race fix"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/liblockdep: don't include host headers
  tools/liblockdep: ignore generated .so file
  smpboot: Add missing get_online_cpus() in smpboot_register_percpu_thread()
2015-02-06 13:06:10 -08:00
Josh Poimboeuf f638f4dc08 livepatch: add missing newline to error message
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-02-06 21:28:35 +01:00
Marcel Holtmann ab92ebbb8e module: Remove double spaces in module verification taint message
The warning message when loading modules with a wrong signature has
two spaces in it:

"module verification failed: signature and/or  required key missing"

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-06 15:31:41 +10:30
Andrey Tsyvarev de96d79f34 kernel/module.c: Free lock-classes if parse_args failed
parse_args call module parameters' .set handlers, which may use locks defined in the module.
So, these classes should be freed in case parse_args returns error(e.g. due to incorrect parameter passed).

Signed-off-by: Andrey Tsyvarev <tsyvarev@ispras.ru>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-06 15:31:40 +10:30
David S. Miller 6e03f896b5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/vxlan.c
	drivers/vhost/net.c
	include/linux/if_vlan.h
	net/core/dev.c

The net/core/dev.c conflict was the overlap of one commit marking an
existing function static whilst another was adding a new function.

In the include/linux/if_vlan.h case, the type used for a local
variable was changed in 'net', whereas the function got rewritten
to fix a stacked vlan bug in 'net-next'.

In drivers/vhost/net.c, Al Viro's iov_iter conversions in 'net-next'
overlapped with an endainness fix for VHOST 1.0 in 'net'.

In drivers/net/vxlan.c, vxlan_find_vni() added a 'flags' parameter
in 'net-next' whereas in 'net' there was a bug fix to pass in the
correct network namespace pointer in calls to this function.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05 14:33:28 -08:00
Jiang Liu 90e9782061 resources: Move struct resource_list_entry from ACPI into resource core
Currently ACPI, PCI and pnp all implement the same resource list
management with different data structure. We need to transfer from
one data structure into another when passing resources from one
subsystem into another subsystem. So move struct resource_list_entry
from ACPI into resource core and rename it as resource_entry,
then it could be reused by different subystems and avoid the data
structure conversion.

Introduce dedicated header file resource_ext.h instead of embedding
it into ioport.h to avoid header file inclusion order issues.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-05 15:09:25 +01:00
John Stultz 2d926c15d6 hrtimer: Fix incorrect tai offset calculation for non high-res timer systems
I noticed some CLOCK_TAI timer test failures on one of my
less-frequently used configurations. And after digging in I
found in 76f4108892 (Cleanup hrtimer accessors to the
timekepeing state), the hrtimer_get_softirq_time tai offset
calucation was incorrectly rewritten, as the tai offset we
return shold be from CLOCK_MONOTONIC, and not CLOCK_REALTIME.

This results in CLOCK_TAI timers expiring early on non-highres
capable machines.

This patch fixes the issue, calculating the tai time properly
from the monotonic base.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable <stable@vger.kernel.org> # 3.17+
Link: http://lkml.kernel.org/r/1423097126-10236-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-05 08:39:37 +01:00
Andy Lutomirski c1317ec2b9 perf: Pass the event to arch_perf_update_userpage()
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/0fea9a7fac3c1eea86cb0a5954184e74f4213666.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 12:10:46 +01:00
Andy Lutomirski 1e0fb9ec67 perf: Add pmu callbacks to track event mapping and unmapping
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Vince Weaver <vince@deater.net>
Cc: "hillf.zj" <hillf.zj@alibaba-inc.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/266afcba1d1f91ea5501e4e16e94bbbc1a9339b6.1414190806.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 12:10:45 +01:00
Josh Poimboeuf 12cf89b550 livepatch: rename config to CONFIG_LIVEPATCH
Rename CONFIG_LIVE_PATCHING to CONFIG_LIVEPATCH to make the naming of
the config and the code more consistent.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-02-04 11:25:51 +01:00
Ingo Molnar 0967160ad6 Merge branch 'x86/asm' into perf/x86, to avoid conflicts with upcoming patches
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 09:01:12 +01:00
Mark Rutland 2fde4f94e0 perf: Decouple unthrottling and rotating
Currently the adjusments made as part of perf_event_task_tick() use the
percpu rotation lists to iterate over any active PMU contexts, but these
are not used by the context rotation code, having been replaced by
separate (per-context) hrtimer callbacks. However, some manipulation of
the rotation lists (i.e. removal of contexts) has remained in
perf_rotate_context(). This leads to the following issues:

* Contexts are not always removed from the rotation lists. Removal of
  PMUs which have been placed in rotation lists, but have not been
  removed by a hrtimer callback can result in corruption of the rotation
  lists (when memory backing the context is freed).

  This has been observed to result in hangs when PMU drivers built as
  modules are inserted and removed around the creation of events for
  said PMUs.

* Contexts which do not require rotation may be removed from the
  rotation lists as a result of a hrtimer, and will not be considered by
  the unthrottling code in perf_event_task_tick.

This patch fixes the issue by updating the rotation ist when events are
scheduled in/out, ensuring that each rotation list stays in sync with
the HW state. As each event holds a refcount on the module of its PMU,
this ensures that when a PMU module is unloaded none of its CPU contexts
can be in a rotation list. By maintaining a list of perf_event_contexts
rather than perf_event_cpu_contexts, we don't need separate paths to
handle the cpu and task contexts, which also makes the code a little
simpler.

As the rotation_list variables are not used for rotation, these are
renamed to active_ctx_list, which better matches their current function.
perf_pmu_rotate_{start,stop} are renamed to
perf_pmu_ctx_{activate,deactivate}.

Reported-by: Johannes Jensen <johannes.jensen@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Will Deacon <Will.Deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150129134511.GR17721@leverpostej
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 08:07:16 +01:00
Mark Rutland cc34b98bac perf: Drop module reference on event init failure
When initialising an event, perf_init_event will call try_module_get() to
ensure that the PMU's module cannot be removed for the lifetime of the
event, with __free_event() dropping the reference when the event is
finally destroyed. If something fails after the event has been
initialised, but before the event is installed, perf_event_alloc will
drop the reference on the module.

However, if we fail to initialise an event for some reason (e.g. we ask
an uncore PMU to perform sampling, and it refuses to initialise the
event), we do not drop the refcount. If we try to open such a bogus
event without a precise IDR type, we will loop over each PMU in the pmus
list, incrementing each of their refcounts without decrementing them.

This patch adds a module_put when pmu->event_init(event) fails, ensuring
that the refcounts are balanced in failure cases. As the innards of the
precise and search based initialisation look very similar, this logic is
hoisted out into a new helper function. While the early return for the
failed try_module_get is removed from the search case, this is handled
by the remaining return when ret is not -ENOENT.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1420642611-22667-1-git-send-email-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 08:07:14 +01:00
Jiri Olsa 7c60fc0e02 perf: Use POLLIN instead of POLL_IN for perf poll data in flag
Currently we flag available data (via poll syscall) on perf fd with
POLL_IN macro, which is normally used for SIGIO interface.

We've been lucky, because POLLIN (0x1) is subset of POLL_IN (0x20001)
and sys_poll (do_pollfd function) cut the extra bit out (0x20000).

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1422467678-22341-1-git-send-email-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 08:07:13 +01:00
Peter Zijlstra a83fe28e2e perf: Fix put_event() ctx lock
So what I suspect; but I'm in zombie mode today it seems; is that while
I initially thought that it was impossible for ctx to change when
refcount dropped to 0, I now suspect its possible.

Note that until perf_remove_from_context() the event is still active and
visible on the lists. So a concurrent sys_perf_event_open() from another
task into this task can race.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephane Eranian <eranian@gmail.com>
Cc: mark.rutland@arm.com
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150129134434.GB26304@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 08:07:12 +01:00
Peter Zijlstra (Intel) 8f95b435b6 perf: Fix move_group() order
Jiri reported triggering the new WARN_ON_ONCE in event_sched_out over
the weekend:

  event_sched_out.isra.79+0x2b9/0x2d0
  group_sched_out+0x69/0xc0
  ctx_sched_out+0x106/0x130
  task_ctx_sched_out+0x37/0x70
  __perf_install_in_context+0x70/0x1a0
  remote_function+0x48/0x60
  generic_exec_single+0x15b/0x1d0
  smp_call_function_single+0x67/0xa0
  task_function_call+0x53/0x80
  perf_install_in_context+0x8b/0x110

I think the below should cure this; if we install a group leader it
will iterate the (still intact) group list and find its siblings and
try and install those too -- even though those still have the old
event->ctx -- in the new ctx.

Upon installing the first group sibling we'd try and schedule out the
group and trigger the above warn.

Fix this by installing the group leader last, installing siblings
would have no effect, they're not reachable through the group lists
and therefore we don't schedule them.

Also delay resetting the state until we're absolutely sure the events
are quiescent.

Reported-by: Jiri Olsa <jolsa@redhat.com>
Reported-by: vincent.weaver@maine.edu
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150126162639.GA21418@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 08:07:11 +01:00
Peter Zijlstra f63a8daa58 perf: Fix event->ctx locking
There have been a few reported issues wrt. the lack of locking around
changing event->ctx. This patch tries to address those.

It avoids the whole rwsem thing; and while it appears to work, please
give it some thought in review.

What I did fail at is sensible runtime checks on the use of
event->ctx, the RCU use makes it very hard.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150123125834.209535886@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 08:07:10 +01:00
Peter Zijlstra 652884fe0c perf: Add a bit of paranoia
Add a few WARN()s to catch things that should never happen.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150123125834.150481799@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 08:07:09 +01:00
Ingo Molnar 8f4bf4bcc4 Linux 3.19-rc7
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Merge tag 'v3.19-rc7' into perf/core, to merge fixes before applying new changes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:58:29 +01:00
Davidlohr Bueso afffc6c180 locking/rtmutex: Optimize setting task running after being blocked
We explicitly mark the task running after returning from
a __rt_mutex_slowlock() call, which does the actual sleeping
via wait-wake-trylocking. As such, this patch does two things:

(1) refactors the code so that setting current to TASK_RUNNING
    is done by __rt_mutex_slowlock(), and not by the callers. The
    downside to this is that it becomes a bit unclear when at what
    point we block. As such I've added a comment that the task
    blocks when calling __rt_mutex_slowlock() so readers can figure
    out when it is running again.

(2) relaxes setting current's state through __set_current_state(),
    instead of it's more expensive barrier alternative. There was no
    need for the implied barrier as we're obviously not planning on
    blocking.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1422857784.18096.1.camel@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:57:42 +01:00
Davidlohr Bueso 73105994c5 locking/rwsem: Use task->state helpers
Call __set_task_state() instead of assigning the new state
directly. These interfaces also aid CONFIG_DEBUG_ATOMIC_SLEEP
environments, keeping track of who last changed the state.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1422257769-14083-2-git-send-email-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:57:39 +01:00
Nicholas Mc Guire 7c34e3180a sched/completion: Add lock-free checking of the blocking case
The "thread would block" case can be checked without grabbing ->wait.lock.

[ If the check does not return early then grab the lock and recheck.
  A memory barrier is not needed as complete() and complete_all() imply
  a barrier.

  The ACCESS_ONCE() is needed for calls in a loop that, if inlined, could
  optimize out the re-fetching of x->done. ]

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1422013307-13200-1-git-send-email-der.herr@hofr.at
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:57:37 +01:00
Nicholas Mc Guire de30ec4730 sched/completion: Remove unnecessary ->wait.lock serialization when reading completion state
Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1421467534-22834-1-git-send-email-der.herr@hofr.at
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:57:36 +01:00
Davidlohr Bueso 51587bcf31 locking/mutex: Explicitly mark task as running after wakeup
By the time we wake up and get the lock after being asleep
in the slowpath, we better be running. As good practice,
be explicit about this and avoid any mischief.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1421717961.4903.11.camel@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:57:33 +01:00
Ingo Molnar 2622e849a1 Linux 3.19-rc7
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Merge tag 'v3.19-rc7' into locking/core, to refresh the branch before applying new changes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:53:17 +01:00
Sharon Dvir 139b6fd26d sched/Documentation: Remove unneeded word
The second 'mutex' shouldn't be there, it can't be about the mutex,
as the mutex can't be freed, but unlocked, the memory where the
mutex resides however, can be freed.

Signed-off-by: Sharon Dvir <sharon.dvir1@mail.huji.ac.il>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1422827252-31363-1-git-send-email-sharon.dvir1@mail.huji.ac.il
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:52:33 +01:00
Frederic Weisbecker bfd9b2b5f8 sched: Pull resched loop to __schedule() callers
__schedule() disables preemption during its job and re-enables it
afterward without doing a preemption check to avoid recursion.

But if an event happens after the context switch which requires
rescheduling, we need to check again if a task of a higher priority
needs the CPU. A preempt irq can raise such a situation. To handle that,
__schedule() loops on need_resched().

But preempt_schedule_*() functions, which call __schedule(), also loop
on need_resched() to handle missed preempt irqs. Hence we end up with
the same loop happening twice.

Lets simplify that by attributing the need_resched() loop responsibility
to all __schedule() callers.

There is a risk that the outer loop now handles reschedules that used
to be handled by the inner loop with the added overhead of caller details
(inc/dec of PREEMPT_ACTIVE, irq save/restore) but assuming those inner
rescheduling loop weren't too frequent, this shouldn't matter. Especially
since the whole preemption path is now losing one loop in any case.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1422404652-29067-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:52:30 +01:00
Xunlei Pang 9659e1eeee sched/deadline: Remove cpu_active_mask from cpudl_find()
cpu_active_mask is rarely changed (only on hotplug), so remove this
operation to gain a little performance.

If there is a change in cpu_active_mask, rq_online_dl() and
rq_offline_dl() should take care of it normally, so cpudl::free_cpus
carries enough information for us.

For the rare case when a task is put onto a dying cpu (which
rq_offline_dl() can't handle in a timely fashion), it will be
handled through _cpu_down()->...->multi_cpu_stop()->migration_call()
->migrate_tasks(), preventing the task from hanging on the
dead cpu.

Cc: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
[peterz: changelog]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421642980-10045-2-git-send-email-pang.xunlei@linaro.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:52:29 +01:00
Wanpeng Li 868933359a sched: Fix hrtick_start() on UP
The commit 177ef2a631 ("sched/deadline: Fix a precision problem in
the microseconds range") forgot to change the UP version of
hrtick_start(), do so now.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Fixes: 177ef2a631 ("sched/deadline: Fix a precision problem in the microseconds range")
[ Fixed the changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Kirill Tkhai <ktkhai@parallels.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1416962647-76792-7-git-send-email-wanpeng.li@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:52:28 +01:00
Wanpeng Li 75381608e8 sched/deadline: Avoid pointless __setscheduler()
There is no need to dequeue/enqueue and push/pull if there are
no scheduling parameters changed for the DL class.

Both fair and RT classes already check if parameters changed for
them to avoid unnecessary overhead. This patch add the parameters
changed test for the DL class in order to reduce overhead.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
[ Fixed up the changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Kirill Tkhai <ktkhai@parallels.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1416962647-76792-5-git-send-email-wanpeng.li@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:52:27 +01:00
Peter Zijlstra 1019a359d3 sched/deadline: Fix stale yield state
When we fail to start the deadline timer in update_curr_dl(), we
forget to clear ->dl_yielded, resulting in wrecked time keeping.

Since the natural place to clear both ->dl_yielded and ->dl_throttled
is in replenish_dl_entity(); both are after all waiting for that event;
make it so.

Luckily since 67dfa1b756 ("sched/deadline: Implement
cancel_dl_timer() to use in switched_from_dl()") the
task_on_rq_queued() condition in dl_task_timer() must be true, and can
therefore call enqueue_task_dl() unconditionally.

Reported-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kirill Tkhai <ktkhai@parallels.com>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1416962647-76792-4-git-send-email-wanpeng.li@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:52:26 +01:00
Wanpeng Li a7bebf4887 sched/deadline: Fix hrtick for a non-leftmost task
After update_curr_dl() the current task might not be the leftmost task
anymore. In that case do not start a new hrtick for it.

In this case NEED_RESCHED will be set and the next schedule will start
the hrtick for the new task if and when appropriate.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Acked-by: Juri Lelli <juri.lelli@arm.com>
[ Rewrote the changelog and comment. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kirill Tkhai <ktkhai@parallels.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1416962647-76792-2-git-send-email-wanpeng.li@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:52:25 +01:00
Ingo Molnar 4c195c8a19 Merge branch 'sched/urgent' into sched/core, to merge fixes before applying new patches
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:44:00 +01:00
Peter Zijlstra 40767b0dc7 sched/deadline: Fix deadline parameter modification handling
Commit 67dfa1b756 ("sched/deadline: Implement cancel_dl_timer() to
use in switched_from_dl()") removed the hrtimer_try_cancel() function
call out from init_dl_task_timer(), which gets called from
__setparam_dl().

The result is that we can now re-init the timer while its active --
this is bad and corrupts timer state.

Furthermore; changing the parameters of an active deadline task is
tricky in that you want to maintain guarantees, while immediately
effective change would allow one to circumvent the CBS guarantees --
this too is bad, as one (bad) task should not be able to affect the
others.

Rework things to avoid both problems. We only need to initialize the
timer once, so move that to __sched_fork() for new tasks.

Then make sure __setparam_dl() doesn't affect the current running
state but only updates the parameters used to calculate the next
scheduling period -- this guarantees the CBS functions as expected
(albeit slightly pessimistic).

This however means we need to make sure __dl_clear_params() needs to
reset the active state otherwise new (and tasks flipping between
classes) will not properly (re)compute their first instance.

Todo: close class flipping CBS hole.
Todo: implement delayed BW release.

Reported-by: Luca Abeni <luca.abeni@unitn.it>
Acked-by: Juri Lelli <juri.lelli@arm.com>
Tested-by: Luca Abeni <luca.abeni@unitn.it>
Fixes: 67dfa1b756 ("sched/deadline: Implement cancel_dl_timer() to use in switched_from_dl()")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150128140803.GF23038@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-04 07:42:48 +01:00
Wonhong Kwon a64fc82c4f PM / hibernate: exclude freed pages from allocated pages printout
hibernate_preallocate_memory() prints out that how many pages are
allocated, but it doesn't take into consideration the pages freed by
free_unnecessary_pages(). Therefore, it always shows the count more
than actually allocated.

Signed-off-by: Wonhong Kwon <wonhong.kwon@lge.com>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-02-03 22:53:53 +01:00
Ingo Molnar 8dbcb8737c Linux 3.19-rc7
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Merge tag 'v3.19-rc7' into x86/asm, to refresh the branch before pulling in new changes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-03 12:22:18 +01:00
Steven Rostedt (Red Hat) 7eeafbcab4 tracing: Separate out initializing top level dir from instances
The top level trace array is treated a little different than the
instances, as it has to deal with more of the general tracing.
The tr->dir is the tracing directory, which is an immutable
dentry, where as the tr->dir of instances are the dentry that
was created, and can be destroyed later. These should have different
functions accessing them.

As only tracing_init_dentry() deals with the top level array, fold
the code for it into that function, and remove the trace_init_dentry_tr()
that was also used by the instances to get their directory dentry.

Add a tracing_get_dentry() to just get the tracing dir entry for
instances as well as the top level array.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-02-02 10:22:34 -05:00
Steven Rostedt (Red Hat) c602894814 tracing: Make tracing_init_dentry_tr() static
tracing_init_dentry_tr() is not used outside of trace.c, it should
be static.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-02-02 10:22:23 -05:00
Cody P Schafer fd979c0132 perf: provide sysfs_show for struct perf_pmu_events_attr
(struct perf_pmu_events_attr) is defined in include/linux/perf_event.h,
but the only "show" for it is in x86 and contains x86 specific stuff.

Make a generic one for those of us who are just using the event_str.

Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-02-02 17:56:36 +11:00
Linus Torvalds 00845eb968 sched: don't cause task state changes in nested sleep debugging
Commit 8eb23b9f35 ("sched: Debug nested sleeps") added code to report
on nested sleep conditions, which we generally want to avoid because the
inner sleeping operation can re-set the thread state to TASK_RUNNING,
but that will then cause the outer sleep loop not actually sleep when it
calls schedule.

However, that's actually valid traditional behavior, with the inner
sleep being some fairly rare case (like taking a sleeping lock that
normally doesn't actually need to sleep).

And the debug code would actually change the state of the task to
TASK_RUNNING internally, which makes that kind of traditional and
working code not work at all, because now the nested sleep doesn't just
sometimes cause the outer one to not block, but will cause it to happen
every time.

In particular, it will cause the cardbus kernel daemon (pccardd) to
basically busy-loop doing scheduling, converting a laptop into a heater,
as reported by Bruno Prémont.  But there may be other legacy uses of
that nested sleep model in other drivers that are also likely to never
get converted to the new model.

This fixes both cases:

 - don't set TASK_RUNNING when the nested condition happens (note: even
   if WARN_ONCE() only _warns_ once, the return value isn't whether the
   warning happened, but whether the condition for the warning was true.
   So despite the warning only happening once, the "if (WARN_ON(..))"
   would trigger for every nested sleep.

 - in the cases where we knowingly disable the warning by using
   "sched_annotate_sleep()", don't change the task state (that is used
   for all core scheduling decisions), instead use '->task_state_change'
   that is used for the debugging decision itself.

(Credit for the second part of the fix goes to Oleg Nesterov: "Can't we
avoid this subtle change in behaviour DEBUG_ATOMIC_SLEEP adds?" with the
suggested change to use 'task_state_change' as part of the test)

Reported-and-bisected-by: Bruno Prémont <bonbons@linux-vserver.org>
Tested-by: Rafael J Wysocki <rjw@rjwysocki.net>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Cc: Ilya Dryomov <ilya.dryomov@inktank.com>,
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>,
Cc: Davidlohr Bueso <dave@stgolabs.net>,
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-01 12:23:32 -08:00
Linus Torvalds 6155bc1431 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, but also an event groups fix, two PMU driver
  fixes and a CPU model variant addition"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Tighten (and fix) the grouping condition
  perf/x86/intel: Add model number for Airmont
  perf/rapl: Fix crash in rapl_scale()
  perf/x86/intel/uncore: Move uncore_box_init() out of driver initialization
  perf probe: Fix probing kretprobes
  perf symbols: Introduce 'for' method to iterate over the symbols with a given name
  perf probe: Do not rely on map__load() filter to find symbols
  perf symbols: Introduce method to iterate symbols ordered by name
  perf symbols: Return the first entry with a given name in find_by_name method
  perf annotate: Fix memory leaks in LOCK handling
  perf annotate: Handle ins parsing failures
  perf scripting perl: Force to use stdbool
  perf evlist: Remove extraneous 'was' on error message
2015-01-30 14:34:55 -08:00
Xunlei Pang 16b269436b sched/deadline: Modify cpudl::free_cpus to reflect rd->online
Currently, cpudl::free_cpus contains all CPUs during init, see
cpudl_init(). When calling cpudl_find(), we have to add rd->span
to avoid selecting the cpu outside the current root domain, because
cpus_allowed cannot be depended on when performing clustered
scheduling using the cpuset, see find_later_rq().

This patch adds cpudl_set_freecpu() and cpudl_clear_freecpu() for
changing cpudl::free_cpus when doing rq_online_dl()/rq_offline_dl(),
so we can avoid the rd->span operation when calling cpudl_find()
in find_later_rq().

Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1421642980-10045-1-git-send-email-pang.xunlei@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-30 19:39:16 +01:00
Preeti U Murthy ff6f2d29bd sched/idle: Add missing checks to the exit condition of cpu_idle_poll()
cpu_idle_poll() is entered into when either the cpu_idle_force_poll is set or
tick_check_broadcast_expired() returns true. The exit condition from
cpu_idle_poll() is tif_need_resched().

However this does not take into account scenarios where cpu_idle_force_poll
changes or tick_check_broadcast_expired() returns false, without setting
the resched flag. So a cpu will be caught in cpu_idle_poll() needlessly,
thereby wasting power. Add an explicit check on cpu_idle_force_poll and
tick_check_broadcast_expired() to the exit condition of cpu_idle_poll()
to avoid this.

Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20150121105655.15279.59626.stgit@preeti.in.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-30 19:38:52 +01:00
Frederic Weisbecker a18b5d0181 sched: Fix missing preemption opportunity
If an interrupt fires in cond_resched(), between the call to __schedule()
and the PREEMPT_ACTIVE count decrementation, and that interrupt sets
TIF_NEED_RESCHED, the call to preempt_schedule_irq() will be ignored
due to the PREEMPT_ACTIVE count. This kind of scenario, with irq preemption
being delayed because it's interrupting a preempt-disabled area, is
usually fixed up after preemption is re-enabled back with an explicit
call to preempt_schedule().

This is what preempt_enable() does but a raw preempt count decrement as
performed by __preempt_count_sub(PREEMPT_ACTIVE) doesn't handle delayed
preemption check. Therefore when such a race happens, the rescheduling
is going to be delayed until the next scheduler or preemption entrypoint.
This can be a problem for scheduler latency sensitive workloads.

Lets fix that by consolidating cond_resched() with preempt_schedule()
internals.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Ingo Molnar <mingo@kernel.org>
Original-patch-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421946484-9298-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-30 19:38:51 +01:00
Tim Chen 80e3d87b2c sched/rt: Reduce rq lock contention by eliminating locking of non-feasible target
This patch adds checks that prevens futile attempts to move rt tasks
to a CPU with active tasks of equal or higher priority.

This reduces run queue lock contention and improves the performance of
a well known OLTP benchmark by 0.7%.

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Shawn Bohrer <sbohrer@rgmadvisors.com>
Cc: Suruchi Kadu <suruchi.a.kadu@intel.com>
Cc: Doug Nelson<doug.nelson@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1421430374.2399.27.camel@schen9-desk2.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-30 19:38:49 +01:00
Ingo Molnar 3847b27224 Merge branch 'sched/urgent' into sched/core
Merge all pending fixes and refresh the tree, before applying new changes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-30 19:28:36 +01:00
Todd E Brandt c9257f78b4 PM / sleep: export suspend_resume trace event
Export the suspend_resume tracepoint so it can be used
in loadable modules.

Signed-off-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-30 02:10:41 +01:00
Heiko Carstens c0a80c0c27 ftrace: allow architectures to specify ftrace compile options
If the kernel is compiled with function tracer support the -pg compile option
is passed to gcc to generate extra code into the prologue of each function.

This patch replaces the "open-coded" -pg compile flag with a CC_FLAGS_FTRACE
makefile variable which architectures can override if a different option
should be used for code generation.

Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-01-29 09:19:19 +01:00
Tina Ruchandani da194930ed trace: Use 64-bit timekeeping
The ring_buffer_producer uses 'struct timeval' to measure
its start and end times. 'struct timeval' on 32-bit systems
will have its tv_sec value overflow in year 2038 and beyond.
This patch replaces struct timeval with 'ktime_t' which uses
64-bit representation for nanoseconds.

Link: http://lkml.kernel.org/r/20150128141611.GA2701@tinar

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-01-28 11:02:05 -05:00
Dave Martin 6ea22486ba tracing: Add array printing helper
If a trace event contains an array, there is currently no standard
way to format this for text output.  Drivers are currently hacking
around this by a) local hacks that use the trace_seq functionailty
directly, or b) just not printing that information.  For fixed size
arrays, formatting of the elements can be open-coded, but this gets
cumbersome for arrays of non-trivial size.

These approaches result in non-standard content of the event format
description delivered to userspace, so userland tools needs to be
taught to understand and parse each array printing method
individually.

This patch implements a __print_array() helper that tracepoint
implementations can use instead of reinventing it.  A simple C-style
syntax is used to delimit the array and its elements {like,this}.

So that the helpers can be used with large static arrays as well as
dynamic arrays, they take a pointer and element count: they can be
used with __get_dynamic_array() for use with dynamic arrays.
Link: http://lkml.kernel.org/r/1422449335-8289-2-git-send-email-javi.merino@arm.com

Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-01-28 10:34:47 -05:00