Commit Graph

16578 Commits

Author SHA1 Message Date
Oleg Nesterov 32c5fb7e7d perf: Kill the dead !vma->vm_mm code in perf_event_mmap_event()
1. perf_event_mmap(vma) is never called with a gate_vma-like arg,
   remove the "if (!vma->vm_mm)" code.

2. arch_vma_name() can use the chached value of mmap_event->vma.

3. Change the code to not call arch_vma_name() twice.

4. Purely cosmetic, but since we use "goto got_name" all the time
   remove "else" from "[stack]" branch just for symmetry.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131016200945.GB23214@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 12:02:51 +01:00
Peter Zijlstra d9494cb429 perf: Remove useless atomic_t
There's nothing atomic about atomic_set vs atomic_read; so remove the
atomic_t usage.

Also, make running_sample_length static as it really is (and should
be) local to this translation unit.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: eranian@google.com
Cc: Don Zickus <dzickus@redhat.com>
Cc: jmario@redhat.com
Cc: acme@infradead.org
Cc: dave.hansen@linux.intel.com
Link: http://lkml.kernel.org/n/tip-vw9lg588x1ic248whybjon0c@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-29 12:02:49 +01:00
Ingo Molnar aac898548d Merge branch 'perf/urgent' into perf/core
Conflicts:
	tools/perf/builtin-record.c
	tools/perf/builtin-top.c
	tools/perf/util/hist.h
2013-10-29 11:23:32 +01:00
Linus Torvalds aff22d3f1a Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Ingo Molnar:
 "This tree contains a clockevents regression fix for certain ARM
  subarchitectures"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clockevents: Sanitize ticks to nsec conversion
2013-10-27 10:29:25 -07:00
Linus Torvalds e2756f5e0f Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "The tree contains three fixes:

   - Two tooling fixes

   - Reversal of the new 'MMAP2' extended mmap record ABI, introduced in
     this merge window.  (Patches were proposed to fix it but it was all
     a bit late and we felt it's safer to just delay the ABI one more
     kernel release and do it right)"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Disable PERF_RECORD_MMAP2 support
  perf scripting perl: Fix build error on Fedora 12
  perf probe: Fix to initialize fname always before use it
2013-10-27 10:28:35 -07:00
Linus Torvalds 1c99ca43a4 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fix from Ingo Molnar:
 "This tree fixes a boot crash in CONFIG_DEBUG_MUTEXES=y kernels, on
  kernels built with GCC 3.x (there are still such distros)"

Side note: it's not just a fix for old gcc versions, it's also removing
an incredibly broken/subtle check that LLVM had issues with, and that
made no sense.

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  mutex: Avoid gcc version dependent __builtin_constant_p() usage
2013-10-27 10:18:15 -07:00
Linus Torvalds 20582e34c8 ACPI and power management fixes for 3.12-rc7
- Fix for rounding errors in intel_pstate causing CPU utilization to
    be underestimated from Brennan Shacklett.
 
  - intel_pstate fix to always use the correct max pstate value when
    computing the min pstate from Dirk Brandewie.
 
  - Hibernation fix for deadlocking resume in cases when the probing
    of the device containing the image is deferred from Russ Dill.
 
  - acpi-cpufreq fix to prevent the module from staying in memory
    when the driver cannot be registered and then attempting to
    unregister things that have never been registered on exit.
 
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Merge tag 'pm+acpi-3.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from
 "These fix two bugs in the intel_pstate driver, a hibernate bug leading
  to nasty resume failures sometimes and acpi-cpufreq initialization bug
  that causes problems to happen during module unload when intel_pstate
  is in use.

  Specifics:

   - Fix for rounding errors in intel_pstate causing CPU utilization to
     be underestimated from Brennan Shacklett.

   - intel_pstate fix to always use the correct max pstate value when
     computing the min pstate from Dirk Brandewie.

   - Hibernation fix for deadlocking resume in cases when the probing of
     the device containing the image is deferred from Russ Dill.

   - acpi-cpufreq fix to prevent the module from staying in memory when
     the driver cannot be registered and then attempting to unregister
     things that have never been registered on exit"

* tag 'pm+acpi-3.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  acpi-cpufreq: Fail initialization if driver cannot be registered
  PM / hibernate: Move software_resume to late_initcall_sync
  intel_pstate: Correct calculation of min pstate value
  intel_pstate: Improve accuracy by not truncating until final result
2013-10-26 04:38:47 +01:00
Russ Dill d3c345dbc7 PM / hibernate: Move software_resume to late_initcall_sync
software_resume is being called after deferred_probe_initcall in
drivers base. If the probing of the device that contains the resume
image is deferred, and the system has been instructed to wait for
it to show up, this wait will occur in software_resume. This causes
a deadlock.

Move software_resume into late_initcall_sync so that it happens
after all the other late_initcalls.

Signed-off-by: Russ Dill <Russ.Dill@ti.com>
Acked-by: Pavel Machek <Pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-25 01:58:49 +02:00
Thomas Gleixner 97b9410643 clockevents: Sanitize ticks to nsec conversion
Marc Kleine-Budde pointed out, that commit 77cc982 "clocksource: use
clockevents_config_and_register() where possible" caused a regression
for some of the converted subarchs.

The reason is, that the clockevents core code converts the minimal
hardware tick delta to a nanosecond value for core internal
usage. This conversion is affected by integer math rounding loss, so
the backwards conversion to hardware ticks will likely result in a
value which is less than the configured hardware limitation. The
affected subarchs used their own workaround (SIGH!) which got lost in
the conversion.

The solution for the issue at hand is simple: adding evt->mult - 1 to
the shifted value before the integer divison in the core conversion
function takes care of it. But this only works for the case where for
the scaled math mult/shift pair "mult <= 1 << shift" is true. For the
case where "mult > 1 << shift" we can apply the rounding add only for
the minimum delta value to make sure that the backward conversion is
not less than the given hardware limit. For the upper bound we need to
omit the rounding add, because the backwards conversion is always
larger than the original latch value. That would violate the upper
bound of the hardware device.

Though looking closer at the details of that function reveals another
bogosity: The upper bounds check is broken as well. Checking for a
resulting "clc" value greater than KTIME_MAX after the conversion is
pointless. The conversion does:

      u64 clc = (latch << evt->shift) / evt->mult;

So there is no sanity check for (latch << evt->shift) exceeding the
64bit boundary. The latch argument is "unsigned long", so on a 64bit
arch the handed in argument could easily lead to an unnoticed shift
overflow. With the above rounding fix applied the calculation before
the divison is:

       u64 clc = (latch << evt->shift) + evt->mult - 1;

So we need to make sure, that neither the shift nor the rounding add
is overflowing the u64 boundary.

[ukl: move assignment to rnd after eventually changing mult, fix build
 issue and correct comment with the right math]

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: nicolas.ferre@atmel.com
Cc: Marc Pignat <marc.pignat@hevs.ch>
Cc: john.stultz@linaro.org
Cc: kernel@pengutronix.de
Cc: Ronald Wahl <ronald.wahl@raritan.com>
Cc: LAK <linux-arm-kernel@lists.infradead.org>
Cc: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1380052223-24139-1-git-send-email-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2013-10-23 12:51:21 +02:00
Linus Torvalds ee7eafc907 Merge branch 'for-3.12-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "Two late fixes for cgroup.

  One fixes descendant walk introduced during this rc1 cycle.  The other
  fixes a post 3.9 bug during task attach which can lead to hang.  Both
  fixes are critical and the fixes are relatively straight-forward"

* 'for-3.12-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix to break the while loop in cgroup_attach_task() correctly
  cgroup: fix cgroup post-order descendant walk of empty subtree
2013-10-22 08:20:34 +01:00
Ingo Molnar e4f8eaad70 perf/urgent fixes:
. Fix build error on Fedora 12.
 
 . Fix to initialize fname always before use it, bug introduced
   during this merge window, from Masami Hiramatsu.
 
 . Disable PERF_RECORD_MMAP2 support, from Stephane Eranian.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

" * Fix build error on Fedora 12.

  * Fix to initialize fname always before use it, bug introduced
    during this merge window, from Masami Hiramatsu.

  * Disable PERF_RECORD_MMAP2 support, from Stephane Eranian. "

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-20 10:51:35 +02:00
Tetsuo Handa b0267507df mutex: Avoid gcc version dependent __builtin_constant_p() usage
Commit 040a0a37 ("mutex: Add support for wound/wait style locks")
used "!__builtin_constant_p(p == NULL)" but gcc 3.x cannot
handle such expression correctly, leading to boot failure when
built with CONFIG_DEBUG_MUTEXES=y.

Fix it by explicitly passing a bool which tells whether p != NULL
or not.

[ PeterZ: This is a sad patch, but provided it actually generates
          similar code I suppose its the best we can do bar whole
	  sale deprecating gcc-3. ]

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: peterz@infradead.org
Cc: imirkin@alum.mit.edu
Cc: daniel.vetter@ffwll.ch
Cc: robdclark@gmail.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/201310171945.AGB17114.FSQVtHOJFOOFML@I-love.SAKURA.ne.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-18 21:58:54 +02:00
Stephane Eranian 3090ffb5a2 perf: Disable PERF_RECORD_MMAP2 support
For now, we disable the extended MMAP record support (MMAP2).

We have identified cases where it would not report the correct mapping
information, clone(VM_CLONE) but with separate pids.  We will revisit
the support once we find a solution for this case.

The patch changes the kernel to return EINVAL if attr->mmap2 is set. The
patch also modifies the perf tool to use regular PERF_RECORD_MMAP for
synthetic events and it also prevents the tool from requesting
attr->mmap2 mode because the kernel would reject it.

The support will be revisited once the kenrel interface is updated.

In V2, we reduce the patch to the strict minimum.

In V3, we avoid calling perf_event_open() with mmap2 set because we know
it will fail and require fallback retry.

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131017173215.GA8820@quad
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-10-17 16:27:14 -03:00
Ingo Molnar 426ee9e3bb Linux 3.12-rc5
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Merge tag 'v3.12-rc5' into perf/core

Merge Linux v3.12-rc5, to pick up the latest fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-15 07:05:18 +02:00
Anjana V Kumar ea84753c98 cgroup: fix to break the while loop in cgroup_attach_task() correctly
Both Anjana and Eunki reported a stall in the while_each_thread loop
in cgroup_attach_task().

It's because, when we attach a single thread to a cgroup, if the cgroup
is exiting or is already in that cgroup, we won't break the loop.

If the task is already in the cgroup, the bug can lead to another thread
being attached to the cgroup unexpectedly:

  # echo 5207 > tasks
  # cat tasks
  5207
  # echo 5207 > tasks
  # cat tasks
  5207
  5215

What's worse, if the task to be attached isn't the leader of the thread
group, we might never exit the loop, hence cpu stall. Thanks for Oleg's
analysis.

This bug was introduced by commit 081aa458c3
("cgroup: consolidate cgroup_attach_task() and cgroup_attach_proc()")

[ lizf: - fixed the first continue, pointed out by Oleg,
        - rewrote changelog. ]

Cc: <stable@vger.kernel.org> # 3.9+
Reported-by: Eunki Kim <eunki_kim@samsung.com>
Reported-by: Anjana V Kumar <anjanavk12@gmail.com>
Signed-off-by: Anjana V Kumar <anjanavk12@gmail.com>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2013-10-13 16:07:10 -04:00
Linus Torvalds 0e7a3ed04f Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Various fixlets:

  On the kernel side:

   - fix a race
   - fix a bug in the handling of the perf ring-buffer data page

  On the tooling side:

   - fix the handling of certain corrupted perf.data files
   - fix a bug in 'perf probe'
   - fix a bug in 'perf record + perf sched'
   - fix a bug in 'make install'
   - fix a bug in libaudit feature-detection on certain distros"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf session: Fix infinite loop on invalid perf.data file
  perf tools: Fix installation of libexec components
  perf probe: Fix to find line information for probe list
  perf tools: Fix libaudit test
  perf stat: Set child_pid after perf_evlist__prepare_workload()
  perf tools: Add default handler for mmap2 events
  perf/x86: Clean up cap_user_time* setting
  perf: Fix perf_pmu_migrate_context
2013-10-08 09:23:12 -07:00
Linus Torvalds 7dee8dff47 ACPI and power management fixes for 3.12-rc4
1) The resume part of user space driven hibernation (s2disk) is now
     broken after the change that moved the creation of memory bitmaps
     to after the freezing of tasks, because I forgot that the resume
     utility loaded the image before freezing tasks and needed the
     bitmaps for that.  The fix adds special handling for that case.
 
  2) One of recent commits changed the export of acpi_bus_get_device()
     to EXPORT_SYMBOL_GPL(), which was technically correct but broke
     existing binary modules using that function including one in
     particularly widespread use.  Change it back to EXPORT_SYMBOL().
 
  3) The intel_pstate driver sometimes fails to disable turbo if its
     no_turbo sysfs attribute is set.  Fix from Srinivas Pandruvada.
 
  4) One of recent cpufreq fixes forgot to update a check in cpufreq-cpu0
     which still (incorrectly) treats non-NULL as non-error.  Fix from
     Philipp Zabel.
 
  5) The SPEAr cpufreq driver uses a wrong variable type in one place
     preventing it from catching errors returned by one of the functions
     called by it.  Fix from Sachin Kamat.
 
 /
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Merge tag 'pm+acpi-3.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael Wysocki:

 - The resume part of user space driven hibernation (s2disk) is now
   broken after the change that moved the creation of memory bitmaps to
   after the freezing of tasks, because I forgot that the resume utility
   loaded the image before freezing tasks and needed the bitmaps for
   that.  The fix adds special handling for that case.

 - One of recent commits changed the export of acpi_bus_get_device() to
   EXPORT_SYMBOL_GPL(), which was technically correct but broke existing
   binary modules using that function including one in particularly
   widespread use.  Change it back to EXPORT_SYMBOL().

 - The intel_pstate driver sometimes fails to disable turbo if its
   no_turbo sysfs attribute is set.  Fix from Srinivas Pandruvada.

 - One of recent cpufreq fixes forgot to update a check in cpufreq-cpu0
   which still (incorrectly) treats non-NULL as non-error.  Fix from
   Philipp Zabel.

 - The SPEAr cpufreq driver uses a wrong variable type in one place
   preventing it from catching errors returned by one of the functions
   called by it.  Fix from Sachin Kamat.

* tag 'pm+acpi-3.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: Use EXPORT_SYMBOL() for acpi_bus_get_device()
  intel_pstate: fix no_turbo
  cpufreq: cpufreq-cpu0: NULL is a valid regulator, part 2
  cpufreq: SPEAr: Fix incorrect variable type
  PM / hibernate: Fix user space driven resume regression
2013-10-04 15:03:42 -07:00
Andi Kleen fdfbbd07e9 perf: Add generic transaction flags
Add a generic qualifier for transaction events, as a new sample
type that returns a flag word. This is particularly useful
for qualifying aborts: to distinguish aborts which happen
due to asynchronous events (like conflicts caused by another
CPU) versus instructions that lead to an abort.

The tuning strategies are very different for those cases,
so it's important to distinguish them easily and early.

Since it's inconvenient and inflexible to filter for this
in the kernel we report all the events out and allow
some post processing in user space.

The flags are based on the Intel TSX events, but should be fairly
generic and mostly applicable to other HTM architectures too. In addition
to various flag words there's also reserved space to report an
program supplied abort code. For TSX this is used to distinguish specific
classes of aborts, like a lock busy abort when doing lock elision.

Flags:

Elision and generic transactions 		   (ELISION vs TRANSACTION)
(HLE vs RTM on TSX; IBM etc.  would likely only use TRANSACTION)
Aborts caused by current thread vs aborts caused by others (SYNC vs ASYNC)
Retryable transaction				   (RETRY)
Conflicts with other threads			   (CONFLICT)
Transaction write capacity overflow		   (CAPACITY WRITE)
Transaction read capacity overflow		   (CAPACITY READ)

Transactions implicitely aborted can also return an abort code.
This can be used to signal specific events to the profiler. A common
case is abort on lock busy in a RTM eliding library (code 0xff)
To handle this case we include the TSX abort code

Common example aborts in TSX would be:

- Data conflict with another thread on memory read.
                                      Flags: TRANSACTION|ASYNC|CONFLICT
- executing a WRMSR in a transaction. Flags: TRANSACTION|SYNC
- HLE transaction in user space is too large
                                      Flags: ELISION|SYNC|CAPACITY-WRITE

The only flag that is somewhat TSX specific is ELISION.

This adds the perf core glue needed for reporting the new flag word out.

v2: Add MEM/MISC
v3: Move transaction to the end
v4: Separate capacity-read/write and remove misc
v5: Remove _SAMPLE. Move abort flags to 32bit. Rename
    transaction to txn
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379688044-14173-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04 10:06:08 +02:00
Knut Petersen 723478c8a4 perf: Enforce 1 as lower limit for perf_event_max_sample_rate
/proc/sys/kernel/perf_event_max_sample_rate will accept
negative values as well as 0.

Negative values are unreasonable, and 0 causes a
divide by zero exception in perf_proc_update_handler.

This patch enforces a lower limit of 1.

Signed-off-by: Knut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/5242DB0C.4070005@t-online.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04 10:06:07 +02:00
Peter Zijlstra 9886167d20 perf: Fix perf_pmu_migrate_context
While auditing the list_entry usage due to a trinity bug I found that
perf_pmu_migrate_context violates the rules for
perf_event::event_entry.

The problem is that perf_event::event_entry is a RCU list element, and
hence we must wait for a full RCU grace period before re-using the
element after deletion.

Therefore the usage in perf_pmu_migrate_context() which re-uses the
entry immediately is broken. For now introduce another list_head into
perf_event for this specific usage.

This doesn't actually fix the trinity report because that never goes
through this code.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-mkj72lxagw1z8fvjm648iznw@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-04 09:58:53 +02:00
Ingo Molnar 0d119fb576 Merge branch 'irq/urgent-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into irq/urgent
Pull a hardirq-nesting fix from Frederic Weisbecker.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-02 07:53:01 +02:00
Frederic Weisbecker ded7975475 irq: Force hardirq exit's softirq processing on its own stack
The commit facd8b80c6
("irq: Sanitize invoke_softirq") converted irq exit
calls of do_softirq() to __do_softirq() on all architectures,
assuming it was only used there for its irq disablement
properties.

But as a side effect, the softirqs processed in the end
of the hardirq are always called on the inline current
stack that is used by irq_exit() instead of the softirq
stack provided by the archs that override do_softirq().

The result is mostly safe if the architecture runs irq_exit()
on a separate irq stack because then softirqs are processed
on that same stack that is near empty at this stage (assuming
hardirq aren't nesting).

Otherwise irq_exit() runs in the task stack and so does the softirq
too. The interrupted call stack can be randomly deep already and
the softirq can dig through it even further. To add insult to the
injury, this softirq can be interrupted by a new hardirq, maximizing
the chances for a stack overrun as reported in powerpc for example:

	do_IRQ: stack overflow: 1920
	CPU: 0 PID: 1602 Comm: qemu-system-ppc Not tainted 3.10.4-300.1.fc19.ppc64p7 #1
	Call Trace:
	[c0000000050a8740] .show_stack+0x130/0x200 (unreliable)
	[c0000000050a8810] .dump_stack+0x28/0x3c
	[c0000000050a8880] .do_IRQ+0x2b8/0x2c0
	[c0000000050a8930] hardware_interrupt_common+0x154/0x180
	--- Exception: 501 at .cp_start_xmit+0x3a4/0x820 [8139cp]
		LR = .cp_start_xmit+0x390/0x820 [8139cp]
	[c0000000050a8d40] .dev_hard_start_xmit+0x394/0x640
	[c0000000050a8e00] .sch_direct_xmit+0x110/0x260
	[c0000000050a8ea0] .dev_queue_xmit+0x260/0x630
	[c0000000050a8f40] .br_dev_queue_push_xmit+0xc4/0x130 [bridge]
	[c0000000050a8fc0] .br_dev_xmit+0x198/0x270 [bridge]
	[c0000000050a9070] .dev_hard_start_xmit+0x394/0x640
	[c0000000050a9130] .dev_queue_xmit+0x428/0x630
	[c0000000050a91d0] .ip_finish_output+0x2a4/0x550
	[c0000000050a9290] .ip_local_out+0x50/0x70
	[c0000000050a9310] .ip_queue_xmit+0x148/0x420
	[c0000000050a93b0] .tcp_transmit_skb+0x4e4/0xaf0
	[c0000000050a94a0] .__tcp_ack_snd_check+0x7c/0xf0
	[c0000000050a9520] .tcp_rcv_established+0x1e8/0x930
	[c0000000050a95f0] .tcp_v4_do_rcv+0x21c/0x570
	[c0000000050a96c0] .tcp_v4_rcv+0x734/0x930
	[c0000000050a97a0] .ip_local_deliver_finish+0x184/0x360
	[c0000000050a9840] .ip_rcv_finish+0x148/0x400
	[c0000000050a98d0] .__netif_receive_skb_core+0x4f8/0xb00
	[c0000000050a99d0] .netif_receive_skb+0x44/0x110
	[c0000000050a9a70] .br_handle_frame_finish+0x2bc/0x3f0 [bridge]
	[c0000000050a9b20] .br_nf_pre_routing_finish+0x2ac/0x420 [bridge]
	[c0000000050a9bd0] .br_nf_pre_routing+0x4dc/0x7d0 [bridge]
	[c0000000050a9c70] .nf_iterate+0x114/0x130
	[c0000000050a9d30] .nf_hook_slow+0xb4/0x1e0
	[c0000000050a9e00] .br_handle_frame+0x290/0x330 [bridge]
	[c0000000050a9ea0] .__netif_receive_skb_core+0x34c/0xb00
	[c0000000050a9fa0] .netif_receive_skb+0x44/0x110
	[c0000000050aa040] .napi_gro_receive+0xe8/0x120
	[c0000000050aa0c0] .cp_rx_poll+0x31c/0x590 [8139cp]
	[c0000000050aa1d0] .net_rx_action+0x1dc/0x310
	[c0000000050aa2b0] .__do_softirq+0x158/0x330
	[c0000000050aa3b0] .irq_exit+0xc8/0x110
	[c0000000050aa430] .do_IRQ+0xdc/0x2c0
	[c0000000050aa4e0] hardware_interrupt_common+0x154/0x180
	 --- Exception: 501 at .bad_range+0x1c/0x110
		 LR = .get_page_from_freelist+0x908/0xbb0
	[c0000000050aa7d0] .list_del+0x18/0x50 (unreliable)
	[c0000000050aa850] .get_page_from_freelist+0x908/0xbb0
	[c0000000050aa9e0] .__alloc_pages_nodemask+0x21c/0xae0
	[c0000000050aaba0] .alloc_pages_vma+0xd0/0x210
	[c0000000050aac60] .handle_pte_fault+0x814/0xb70
	[c0000000050aad50] .__get_user_pages+0x1a4/0x640
	[c0000000050aae60] .get_user_pages_fast+0xec/0x160
	[c0000000050aaf10] .__gfn_to_pfn_memslot+0x3b0/0x430 [kvm]
	[c0000000050aafd0] .kvmppc_gfn_to_pfn+0x64/0x130 [kvm]
	[c0000000050ab070] .kvmppc_mmu_map_page+0x94/0x530 [kvm]
	[c0000000050ab190] .kvmppc_handle_pagefault+0x174/0x610 [kvm]
	[c0000000050ab270] .kvmppc_handle_exit_pr+0x464/0x9b0 [kvm]
	[c0000000050ab320]  kvm_start_lightweight+0x1ec/0x1fc [kvm]
	[c0000000050ab4f0] .kvmppc_vcpu_run_pr+0x168/0x3b0 [kvm]
	[c0000000050ab9c0] .kvmppc_vcpu_run+0xc8/0xf0 [kvm]
	[c0000000050aba50] .kvm_arch_vcpu_ioctl_run+0x5c/0x1a0 [kvm]
	[c0000000050abae0] .kvm_vcpu_ioctl+0x478/0x730 [kvm]
	[c0000000050abc90] .do_vfs_ioctl+0x4ec/0x7c0
	[c0000000050abd80] .SyS_ioctl+0xd4/0xf0
	[c0000000050abe30] syscall_exit+0x0/0x98

Since this is a regression, this patch proposes a minimalistic
and low-risk solution by blindly forcing the hardirq exit processing of
softirqs on the softirq stack. This way we should reduce significantly
the opportunities for task stack overflow dug by softirqs.

Longer term solutions may involve extending the hardirq stack coverage to
irq_exit(), etc...

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: #3.9.. <stable@vger.kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
2013-10-01 12:39:08 +02:00
Oleg Nesterov 314a8ad0f1 pidns: fix free_pid() to handle the first fork failure
"case 0" in free_pid() assumes that disable_pid_allocation() should
clear PIDNS_HASH_ADDING before the last pid goes away.

However this doesn't happen if the first fork() fails to create the
child reaper which should call disable_pid_allocation().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-30 14:31:03 -07:00
Tetsuo Handa 4c1c7be95c kernel/kmod.c: check for NULL in call_usermodehelper_exec()
If /proc/sys/kernel/core_pattern contains only "|", a NULL pointer
dereference happens upon core dump because argv_split("") returns
argv[0] == NULL.

This bug was once fixed by commit 264b83c07a ("usermodehelper: check
subprocess_info->path != NULL") but was by error reintroduced by commit
7f57cfa4e2 ("usermodehelper: kill the sub_info->path[0] check").

This bug seems to exist since 2.6.19 (the version which core dump to
pipe was added).  Depending on kernel version and config, some side
effect might happen immediately after this oops (e.g.  kernel panic with
2.6.32-358.18.1.el6).

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-30 14:31:02 -07:00
Rafael J. Wysocki aab1728915 PM / hibernate: Fix user space driven resume regression
Recent commit 8fd37a4 (PM / hibernate: Create memory bitmaps after
freezing user space) broke the resume part of the user space driven
hibernation (s2disk), because I forgot that the resume utility
loaded the image into memory without freezing user space (it still
freezes tasks after loading the image).  This means that during user
space driven resume we need to create the memory bitmaps at the
"device open" time rather than at the "freeze tasks" time, so make
that happen (that's a special case anyway, so it needs to be treated
in a special way).

Reported-and-tested-by: Ronald <ronald645@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-30 19:40:56 +02:00
Linus Torvalds 669fc2f0c7 Merge branches 'sched-urgent-for-linus', 'timers-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler, timer and x86 fixes from Ingo Molnar:
 - A context tracking ARM build and functional fix
 - A handful of ARM clocksource/clockevent driver fixes
 - An AMD microcode patch level sysfs reporting fixlet

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  arm: Fix build error with context tracking calls

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: em_sti: Set cpu_possible_mask to fix SMP broadcast
  clocksource: of: Respect device tree node status
  clocksource: exynos_mct: Set IRQ affinity when the CPU goes online
  arm: clocksource: mvebu: Use the main timer as clock source from DT

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode/AMD: Fix patch level reporting for family 15h
2013-09-28 14:22:17 -07:00
Jean Delvare 3a126f85e0 kernel/params: fix handling of signed integer types
Commit 6072ddc852 ("kernel: replace strict_strto*() with kstrto*()")
broke the handling of signed integer types, fix it.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reported-by: Christian Kujau <lists@nerdbynature.de>
Tested-by: Christian Kujau <lists@nerdbynature.de>
Cc: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-28 12:35:52 -07:00
Ingo Molnar 62d08aec6a Merge branch 'context_tracking/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into sched/urgent
Pull context tracking ARM fix from Frederic Weisbecker.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-28 08:50:09 +02:00
Frederic Weisbecker 0c06a5d4b1 arm: Fix build error with context tracking calls
ad65782fba (context_tracking: Optimize main APIs off case
with static key) converted context tracking main APIs to inline
function and left ARM asm callers behind.

This can be easily fixed by making ARM calling the post static
keys context tracking function. We just need to replicate the
static key checks there. We'll remove these later when ARM will
support the context tracking static keys.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Anil Kumar <anilk4.v@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Kevin Hilman <khilman@linaro.org>
2013-09-27 17:59:47 +02:00
Linus Torvalds 82dfaa58a7 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Three small fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/balancing: Fix cfs_rq->task_h_load calculation
  sched/balancing: Fix 'local->avg_load > busiest->avg_load' case in fix_small_imbalance()
  sched/balancing: Fix 'local->avg_load > sds->avg_load' case in calculate_imbalance()
2013-09-25 13:28:45 -07:00
Linus Torvalds bdc5663fa1 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Assorted standalone fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Add model number for Avoton Silvermont
  perf: Fix capabilities bitfield compatibility in 'struct perf_event_mmap_page'
  perf/x86/intel/uncore: Don't use smp_processor_id() in validate_group()
  perf: Update ABI comment
  tools lib lk: Uninclude linux/magic.h in debugfs.c
  perf tools: Fix old GCC build error in trace-event-parse.c:parse_proc_kallsyms()
  perf probe: Fix finder to find lines of given function
  perf session: Check for SIGINT in more loops
  perf tools: Fix compile with libelf without get_phdrnum
  perf tools: Fix buildid cache handling of kallsyms with kcore
  perf annotate: Fix objdump line parsing offset validation
  perf tools: Fill in new definitions for madvise()/mmap() flags
  perf tools: Sharpen the libaudit dependencies test
2013-09-25 13:28:08 -07:00
Chuansheng Liu e2f0b88e84 kernel/reboot.c: re-enable the function of variable reboot_default
Commit 1b3a5d02ee ("reboot: move arch/x86 reboot= handling to generic
kernel") did some cleanup for reboot= command line, but it made the
reboot_default inoperative.

The default value of variable reboot_default should be 1, and if command
line reboot= is not set, system will use the default reboot mode.

[akpm@linux-foundation.org: fix comment layout]
Signed-off-by: Li Fei <fei.li@intel.com>
Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
Acked-by: Robin Holt <robinmholt@linux.com>
Cc: <stable@vger.kernel.org>	[3.11.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Konstantin Khlebnikov 8ac1c8d5de audit: fix endless wait in audit_log_start()
After commit 829199197a ("kernel/audit.c: avoid negative sleep
durations") audit emitters will block forever if userspace daemon cannot
handle backlog.

After the timeout the waiting loop turns into busy loop and runs until
daemon dies or returns back to work.  This is a minimal patch for that
bug.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Richard Guy Briggs <rgb@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Chuck Anderson <chuck.anderson@oracle.com>
Cc: Dan Duval <dan.duval@oracle.com>
Cc: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Michal Hocko 9809b18fcf watchdog: update watchdog_thresh properly
watchdog_tresh controls how often nmi perf event counter checks per-cpu
hrtimer_interrupts counter and blows up if the counter hasn't changed
since the last check.  The counter is updated by per-cpu
watchdog_hrtimer hrtimer which is scheduled with 2/5 watchdog_thresh
period which guarantees that hrtimer is scheduled 2 times per the main
period.  Both hrtimer and perf event are started together when the
watchdog is enabled.

So far so good.  But...

But what happens when watchdog_thresh is updated from sysctl handler?

proc_dowatchdog will set a new sampling period and hrtimer callback
(watchdog_timer_fn) will use the new value in the next round.  The
problem, however, is that nobody tells the perf event that the sampling
period has changed so it is ticking with the period configured when it
has been set up.

This might result in an ear ripping dissonance between perf and hrtimer
parts if the watchdog_thresh is increased.  And even worse it might lead
to KABOOM if the watchdog is configured to panic on such a spurious
lockup.

This patch fixes the issue by updating both nmi perf even counter and
hrtimers if the threshold value has changed.

The nmi one is disabled and then reinitialized from scratch.  This has
an unpleasant side effect that the allocation of the new event might
fail theoretically so the hard lockup detector would be disabled for
such cpus.  On the other hand such a memory allocation failure is very
unlikely because the original event is deallocated right before.

It would be much nicer if we just changed perf event period but there
doesn't seem to be any API to do that right now.  It is also unfortunate
that perf_event_alloc uses GFP_KERNEL allocation unconditionally so we
cannot use on_each_cpu() and do the same thing from the per-cpu context.
The update from the current CPU should be safe because
perf_event_disable removes the event atomically before it clears the
per-cpu watchdog_ev so it cannot change anything under running handler
feet.

The hrtimer is simply restarted (thanks to Don Zickus who has pointed
this out) if it is queued because we cannot rely it will fire&adopt to
the new sampling period before a new nmi event triggers (when the
treshold is decreased).

[akpm@linux-foundation.org: the UP version of __smp_call_function_single ended up in the wrong place]
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:25 -07:00
Michal Hocko 359e6fab66 watchdog: update watchdog attributes atomically
proc_dowatchdog doesn't synchronize multiple callers which might lead to
confusion when two parallel callers might confuse watchdog_enable_all_cpus
resp watchdog_disable_all_cpus (eg watchdog gets enabled even if
watchdog_thresh was set to 0 already).

This patch adds a local mutex which synchronizes callers to the sysctl
handler.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:25 -07:00
Vladimir Davydov 7e3115ef51 sched/balancing: Fix cfs_rq->task_h_load calculation
Patch a003a2 (sched: Consider runnable load average in move_tasks())
sets all top-level cfs_rqs' h_load to rq->avg.load_avg_contrib, which is
always 0. This mistype leads to all tasks having weight 0 when load
balancing in a cpu-cgroup enabled setup. There obviously should be sum
of weights of all runnable tasks there instead. Fix it.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Reviewed-by: Paul Turner <pjt@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379173186-11944-1-git-send-email-vdavydov@parallels.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-20 11:59:39 +02:00
Vladimir Davydov 3029ede393 sched/balancing: Fix 'local->avg_load > busiest->avg_load' case in fix_small_imbalance()
In busiest->group_imb case we can come to fix_small_imbalance() with
local->avg_load > busiest->avg_load. This can result in wrong imbalance
fix-up, because there is the following check there where all the
members are unsigned:

if (busiest->avg_load - local->avg_load + scaled_busy_load_per_task >=
    (scaled_busy_load_per_task * imbn)) {
	env->imbalance = busiest->load_per_task;
	return;
}

As a result we can end up constantly bouncing tasks from one cpu to
another if there are pinned tasks.

Fix it by substituting the subtraction with an equivalent addition in
the check.

[ The bug can be caught by running 2*N cpuhogs pinned to two logical cpus
  belonging to different cores on an HT-enabled machine with N logical
  cpus: just look at se.nr_migrations growth. ]

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/ef167822e5c5b2d96cf5b0e3e4f4bdff3f0414a2.1379252740.git.vdavydov@parallels.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-20 11:59:38 +02:00
Vladimir Davydov b18855500f sched/balancing: Fix 'local->avg_load > sds->avg_load' case in calculate_imbalance()
In busiest->group_imb case we can come to calculate_imbalance() with
local->avg_load >= busiest->avg_load >= sds->avg_load. This can result
in imbalance overflow, because it is calculated as follows

env->imbalance = min(
	max_pull * busiest->group_power,
	(sds->avg_load - local->avg_load) * local->group_power) / SCHED_POWER_SCALE;

As a result we can end up constantly bouncing tasks from one cpu to
another if there are pinned tasks.

Fix this by skipping the assignment and assuming imbalance=0 in case
local->avg_load > sds->avg_load.

[ The bug can be caught by running 2*N cpuhogs pinned to two logical cpus
  belonging to different cores on an HT-enabled machine with N logical
  cpus: just look at se.nr_migrations growth. ]

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/8f596cc6bc0e5e655119dc892c9bfcad26e971f4.1379252740.git.vdavydov@parallels.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-20 11:59:36 +02:00
Peter Zijlstra fa73158710 perf: Fix capabilities bitfield compatibility in 'struct perf_event_mmap_page'
Solve the problems around the broken definition of perf_event_mmap_page::
cap_usr_time and cap_usr_rdpmc fields which used to overlap, partially
fixed by:

  860f085b74 ("perf: Fix broken union in 'struct perf_event_mmap_page'")

The problem with the fix (merged in v3.12-rc1 and not yet released
officially), noticed by Vince Weaver is that the new behavior is
not detectable by new user-space, and that due to the reuse of the
field names it's easy to mis-compile a binary if old headers are used
on a new kernel or new headers are used on an old kernel.

To solve all that make this change explicit, detectable and self-contained,
by iterating the ABI the following way:

 - Always clear bit 0, and rename it to usrpage->cap_bit0, to at least not
   confuse old user-space binaries. RDPMC will be marked as unavailable
   to old binaries but that's within the ABI, this is a capability bit.

 - Rename bit 1 to ->cap_bit0_is_deprecated and always set it to 1, so new
   libraries can reliably detect that bit 0 is deprecated and perma-zero
   without having to check the kernel version.

 - Use bits 2, 3, 4 for the newly defined, correct functionality:

	cap_user_rdpmc		: 1, /* The RDPMC instruction can be used to read counts */
	cap_user_time		: 1, /* The time_* fields are used */
	cap_user_time_zero	: 1, /* The time_zero field is used */

 - Rename all the bitfield names in perf_event.h to be different from the
   old names, to make sure it's not possible to mis-compile it
   accidentally with old assumptions.

The 'size' field can then be used in the future to add new fields and it
will act as a natural ABI version indicator as well.

Also adjust tools/perf/ userspace for the new definitions, noticed by
Adrian Hunter.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Also-Fixed-by: Adrian Hunter <adrian.hunter@intel.com>
Link: http://lkml.kernel.org/n/tip-zr03yxjrpXesOzzupszqglbv@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-20 09:45:11 +02:00
Linus Torvalds 9d2cd7048b Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Ingo Molnar:
 "An NTP related lockup fix"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Fix HRTICK related deadlock from ntp lock changes
2013-09-18 11:24:49 -05:00
Linus Torvalds 7e28b2712e 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: Fix comment for sched_info_depart
  sched/Documentation: Update sched-design-CFS.txt documentation
  sched/debug: Take PID namespace into account
  sched/fair: Fix small race where child->se.parent,cfs_rq might point to invalid ones
2013-09-18 11:23:32 -05:00
Michael S. Tsirkin 13b62e46d5 sched: Fix comment for sched_info_depart
sched_info_depart seems to be only called from
sched_info_switch(), so only on involuntary task switch.

Fix the comment to match.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Link: http://lkml.kernel.org/r/20130916083036.GA1113@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-16 11:18:34 +02:00
Linus Torvalds 9bf12df31f Merge git://git.kvack.org/~bcrl/aio-next
Pull aio changes from Ben LaHaise:
 "First off, sorry for this pull request being late in the merge window.
  Al had raised a couple of concerns about 2 items in the series below.
  I addressed the first issue (the race introduced by Gu's use of
  mm_populate()), but he has not provided any further details on how he
  wants to rework the anon_inode.c changes (which were sent out months
  ago but have yet to be commented on).

  The bulk of the changes have been sitting in the -next tree for a few
  months, with all the issues raised being addressed"

* git://git.kvack.org/~bcrl/aio-next: (22 commits)
  aio: rcu_read_lock protection for new rcu_dereference calls
  aio: fix race in ring buffer page lookup introduced by page migration support
  aio: fix rcu sparse warnings introduced by ioctx table lookup patch
  aio: remove unnecessary debugging from aio_free_ring()
  aio: table lookup: verify ctx pointer
  staging/lustre: kiocb->ki_left is removed
  aio: fix error handling and rcu usage in "convert the ioctx list to table lookup v3"
  aio: be defensive to ensure request batching is non-zero instead of BUG_ON()
  aio: convert the ioctx list to table lookup v3
  aio: double aio_max_nr in calculations
  aio: Kill ki_dtor
  aio: Kill ki_users
  aio: Kill unneeded kiocb members
  aio: Kill aio_rw_vect_retry()
  aio: Don't use ctx->tail unnecessarily
  aio: io_cancel() no longer returns the io_event
  aio: percpu ioctx refcount
  aio: percpu reqs_available
  aio: reqs_active -> reqs_available
  aio: fix build when migration is disabled
  ...
2013-09-13 10:55:58 -07:00
Martin Schwidefsky 0244ad004a Remove GENERIC_HARDIRQ config option
After the last architecture switched to generic hard irqs the config
options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code
for !CONFIG_GENERIC_HARDIRQS can be removed.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-09-13 15:09:52 +02:00
Linus Torvalds ac4de9543a Merge branch 'akpm' (patches from Andrew Morton)
Merge more patches from Andrew Morton:
 "The rest of MM.  Plus one misc cleanup"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (35 commits)
  mm/Kconfig: add MMU dependency for MIGRATION.
  kernel: replace strict_strto*() with kstrto*()
  mm, thp: count thp_fault_fallback anytime thp fault fails
  thp: consolidate code between handle_mm_fault() and do_huge_pmd_anonymous_page()
  thp: do_huge_pmd_anonymous_page() cleanup
  thp: move maybe_pmd_mkwrite() out of mk_huge_pmd()
  mm: cleanup add_to_page_cache_locked()
  thp: account anon transparent huge pages into NR_ANON_PAGES
  truncate: drop 'oldsize' truncate_pagecache() parameter
  mm: make lru_add_drain_all() selective
  memcg: document cgroup dirty/writeback memory statistics
  memcg: add per cgroup writeback pages accounting
  memcg: check for proper lock held in mem_cgroup_update_page_stat
  memcg: remove MEMCG_NR_FILE_MAPPED
  memcg: reduce function dereference
  memcg: avoid overflow caused by PAGE_ALIGN
  memcg: rename RESOURCE_MAX to RES_COUNTER_MAX
  memcg: correct RESOURCE_MAX to ULLONG_MAX
  mm: memcg: do not trap chargers with full callstack on OOM
  mm: memcg: rework and document OOM waiting and wakeup
  ...
2013-09-12 15:44:27 -07:00
Jingoo Han 6072ddc852 kernel: replace strict_strto*() with kstrto*()
The usage of strict_strto*() is not preferred, because strict_strto*() is
obsolete.  Thus, kstrto*() should be used.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12 15:38:03 -07:00
Sha Zhengju 1a36e59d48 memcg: reduce function dereference
This function dereferences res far too often, so optimize it.

Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Jeff Liu <jeff.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12 15:38:02 -07:00
Sha Zhengju 3af3351676 memcg: avoid overflow caused by PAGE_ALIGN
Since PAGE_ALIGN is aligning up(the next page boundary), so after
PAGE_ALIGN, the value might be overflow, such as write the MAX value to
*.limit_in_bytes.

  $ cat /cgroup/memory/memory.limit_in_bytes
  18446744073709551615

  # echo 18446744073709551615 > /cgroup/memory/memory.limit_in_bytes
  bash: echo: write error: Invalid argument

Some user programs might depend on such behaviours(like libcg, we read
the value in snapshot, then use the value to reset cgroup later), and
that will cause confusion.  So we need to fix it.

Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Jeff Liu <jeff.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12 15:38:02 -07:00
Sha Zhengju 6de5a8bfca memcg: rename RESOURCE_MAX to RES_COUNTER_MAX
RESOURCE_MAX is far too general name, change it to RES_COUNTER_MAX.

Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Jeff Liu <jeff.liu@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12 15:38:02 -07:00
Linus Torvalds 26935fb06e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile 4 from Al Viro:
 "list_lru pile, mostly"

This came out of Andrew's pile, Al ended up doing the merge work so that
Andrew didn't have to.

Additionally, a few fixes.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (42 commits)
  super: fix for destroy lrus
  list_lru: dynamically adjust node arrays
  shrinker: Kill old ->shrink API.
  shrinker: convert remaining shrinkers to count/scan API
  staging/lustre/libcfs: cleanup linux-mem.h
  staging/lustre/ptlrpc: convert to new shrinker API
  staging/lustre/obdclass: convert lu_object shrinker to count/scan API
  staging/lustre/ldlm: convert to shrinkers to count/scan API
  hugepage: convert huge zero page shrinker to new shrinker API
  i915: bail out earlier when shrinker cannot acquire mutex
  drivers: convert shrinkers to new count/scan API
  fs: convert fs shrinkers to new scan/count API
  xfs: fix dquot isolation hang
  xfs-convert-dquot-cache-lru-to-list_lru-fix
  xfs: convert dquot cache lru to list_lru
  xfs: rework buffer dispose list tracking
  xfs-convert-buftarg-lru-to-generic-code-fix
  xfs: convert buftarg LRU to generic code
  fs: convert inode and dentry shrinking to be node aware
  vmscan: per-node deferred work
  ...
2013-09-12 15:01:38 -07:00