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13031 commits

Author SHA1 Message Date
Grant Likely
03848373ea irq_domain: remove NO_IRQ from irq domain code
zero always means no irq when using irq domains.  Get rid of the NO_IRQ
references.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 06:11:21 -07:00
Grant Likely
cc79ca691c irq_domain: Move irq_domain code from powerpc to kernel/irq
This patch only moves the code.  It doesn't make any changes, and the
code is still only compiled for powerpc.  Follow-on patches will generalize
the code for other architectures.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16 01:37:49 -07:00
Thomas Gleixner
97ac984d2f Merge branch 'fortglx/3.4/time' of git://git.linaro.org/people/jstultz/linux into timers/core 2012-02-15 20:29:18 +01:00
Frederic Weisbecker
0a8a2e78b7 timer: Fix bad idle check on irq entry
idle_cpu() is called on irq entry to guess if we need to call
tick_check_idle(). This way we can catch up with jiffies if the tick
was stopped, stop accounting idle time during the interrupt and
maintain the sched clock if it is unstable.

But if we are going to exit the idle loop to schedule a new task (ie:
if we have a task in the runqueue or a remotely enqueued ttwu to
perform), the idle_cpu() check will return 0 such that we miss the
call to tick_check_idle() for all interrupts happening before we
schedule the new task.

As a result these interrupts and the softirqs coming along may deal
with stale jiffies values, bad sched clock values, and won't substract
their time from the idle time accounting.

Fix this with using is_idle_task() instead that strictly checks that
we are running the idle task, without caring about the fact we are
going to schedule a task soon.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/1327427984-23282-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 15:23:09 +01:00
Frederic Weisbecker
15f827be93 nohz: Remove ts->Einidle checks before restarting the tick
ts->inidle is set by tick_nohz_idle_enter() and unset by
tick_nohz_idle_exit(). However these two calls are assumed
to be always paired. This means that by the time we call
tick_nohz_idle_exit(), ts->inidle is supposed to be always
set to 1.

Remove the checks for ts->inidle in tick_nohz_idle_exit().
This simplifies a bit the code and improves its debuggability
(ie: ensure the call is paired with a tick_nohz_idle_enter()
call).

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/1327427984-23282-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 15:23:09 +01:00
Michal Hocko
430ee88195 nohz: Remove update_ts_time_stat from tick_nohz_start_idle
There is no reason to call update_ts_time_stat from tick_nohz_start_idle
anymore (after e0e37c20 sched: Eliminate the ts->idle_lastupdate field)
when we updated idle_lastupdate unconditionally.

We haven't set idle_active yet and do not provide last_update_time so
the whole call end up being just 2 wasted branches.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Link: http://lkml.kernel.org/r/1322755222-6951-1-git-send-email-mhocko@suse.cz
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 15:23:09 +01:00
Suresh Siddha
77b0d60c5a clockevents: Leave the broadcast device in shutdown mode when not needed
Platforms with Always Running APIC Timer doesn't use the broadcast timer
but the kernel is leaving the broadcast timer (HPET in this case)
in oneshot mode.

On these platforms, before the switch to oneshot mode, broadcast device is
actually in shutdown mode. Code checks for empty tick_broadcast_mask and
avoids going into the periodic mode.

During switch to oneshot mode, add the same tick_broadcast_mask checks in the
tick_broadcast_switch_to_oneshot() and avoid the broadcast device going into
the oneshot mode.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: john stultz <johnstul@us.ibm.com>
Cc: venki@google.com
Link: http://lkml.kernel.org/r/1320452301.15071.16.camel@sbsiddha-desk.sc.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 15:23:09 +01:00
Thomas Gleixner
81b40539e7 futex: Simplify return logic
No need to assign ret in each case and break. Simply return the result
of the handler function directly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@linux.intel.com>
2012-02-15 12:19:13 +01:00
Thomas Gleixner
59263b513c futex: Cover all PI opcodes with cmpxchg enabled check
Some of the newer futex PI opcodes do not check the cmpxchg enabled
variable and call unconditionally into the handling functions. Cover
all PI opcodes in a separate check.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@linux.intel.com>
2012-02-15 12:19:13 +01:00
Thomas Gleixner
b4bc724e82 genirq: Handle pending irqs in irq_startup()
An interrupt might be pending when irq_startup() is called, but the
startup code does not invoke the resend logic. In some cases this
prevents the device from issuing another interrupt which renders the
device non functional.

Call the resend function in irq_startup() to keep things going.

Reported-and-tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 11:56:59 +01:00
Thomas Gleixner
ac56376111 genirq: Unmask oneshot irqs when thread was not woken
When the primary handler of an interrupt which is marked IRQ_ONESHOT
returns IRQ_HANDLED or IRQ_NONE, then the interrupt thread is not
woken and the unmask logic of the interrupt line is never
invoked. This keeps the interrupt masked forever.

This was not noticed as most IRQ_ONESHOT users wake the thread
unconditionally (usually because they cannot access the underlying
device from hard interrupt context). Though this behaviour was nowhere
documented and not necessarily intentional. Some drivers can avoid the
thread wakeup in certain cases and run into the situation where the
interrupt line s kept masked.

Handle it gracefully.

Reported-and-tested-by: Lothar Wassmann <lw@karo-electronics.de>
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15 11:56:59 +01:00
Grant Likely
7bb69bade0 irq_domain: Make irq_domain structure match powerpc's irq_host
Part of the series to unify the irq remapping mechanisms in the
kernel.  A follow up patch will copy the powerpc implementation into
kernel/irq/irqdomain.c, which will be a lot easier if the structures
are identical.

Where they differ, I've chose to use the powerpc names since there is
a lot more code using those names.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-14 14:06:48 -07:00
Grant Likely
e1964c50a8 irq_domain: Be less verbose
irq_domain printk's too much.  Drop some output.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Olof Johansson <olof@lixom.net>
2012-02-14 14:06:48 -07:00
Dimitri Sivanich
074b85175a vfs: fix panic in __d_lookup() with high dentry hashtable counts
When the number of dentry cache hash table entries gets too high
(2147483648 entries), as happens by default on a 16TB system, use of a
signed integer in the dcache_init() initialization loop prevents the
dentry_hashtable from getting initialized, causing a panic in
__d_lookup().  Fix this in dcache_init() and similar areas.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-02-13 20:45:38 -05:00
Linus Torvalds
e3f89f4ae4 Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1
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Merge tag 'for-linus' of git://github.com/rustyrussell/linux

* tag 'for-linus' of git://github.com/rustyrussell/linux:
  module: fix broken isapnp handling in file2alias
  module: make module param bint handle nul value
2012-02-13 16:59:53 -08:00
Dave Young
10f296cbfe module: make module param bint handle nul value
Allow bint param accept nul values, just do same as bool param.

Signed-off-by: Dave Young <dyoung@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-02-14 11:02:15 +10:30
Al Viro
4040153087 security: trim security.h
Trim security.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-14 10:45:42 +11:00
Al Viro
191c542442 mm: collapse security_vm_enough_memory() variants into a single function
Collapse security_vm_enough_memory() variants into a single function.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-14 10:45:39 +11:00
Thomas Meyer
47b0edcb59 tracing/trivial: Use kcalloc instead of kzalloc to allocate array
The advantage of kcalloc is, that will prevent integer overflows which could
result from the multiplication of number of elements and size and it is also
a bit nicer to read.

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

Link: http://lkml.kernel.org/r/1322600880.1534.347.camel@localhost.localdomain

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-13 13:48:11 -05:00
Johannes Berg
9510035849 printk/tracing: Add console output tracing
Add a printk.console trace point to record any printk
messages into the trace, regardless of the current
console loglevel. This can help correlate (existing)
printk debugging with other tracing.

Link: http://lkml.kernel.org/r/1322161388.5366.54.camel@jlt3.sipsolutions.net

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-13 13:46:05 -05:00
Rafael J. Wysocki
6f585f750d PM / Sleep: Remove unnecessary label from suspend_freeze_processes()
The Finish label in suspend_freeze_processes() is in fact unnecessary
and makes the function look more complicated than it really is, so
remove that label (along with a few empty lines).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
2012-02-13 16:26:13 +01:00
Rafael J. Wysocki
6c83b4818d PM / Sleep: Do not check wakeup too often in try_to_freeze_tasks()
Use the observation that it is more efficient to check the wakeup
variable once before the loop reporting tasks that were not
frozen in try_to_freeze_tasks() than to do that in every step of that
loop.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-13 16:26:05 +01:00
Jean Pihet
a9b542ee60 PM / QoS: unconditionally build the feature
The PM QoS feature originally didn't depend on CONFIG_PM, which was
mistakenly changed by commit e8db0be124

    PM QoS: Move and rename the implementation files

Later, commit d020283dc6

    PM / QoS: CPU C-state breakage with PM Qos change

partially fixed that by introducing a static inline definition of
pm_qos_request(), but that still didn't allow user space to use
the PM QoS interface if CONFIG_PM was unset (which had been possible
before).  For this reason, remove the dependency of PM QoS on
CONFIG_PM to make it work (as intended) with CONFIG_PM unset.

[rjw: Replaced the original changelog with a new one.]

Signed-off-by: Jean Pihet <j-pihet@ti.com>
Reported-by: Venkatesh Pallipadi <venki@google.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-13 16:23:42 +01:00
Rafael J. Wysocki
654b0c9627 Merge commit 'pm-fixes-for-3.3-rc3' into pm-qos
New material in the pm-qos branch depends on recent power management
fixes.
2012-02-13 16:20:07 +01:00
Geunsik Lim
1e42e83fde ftrace: sched_switch plugin is deprecated
Actually, sched_switch function tracer is merged into wakeup/wakeup_rt
Update 'mini-HOWTO' for ftrace(Kernel function tracer).
If we want to trace "sched:sched_switch" to trace sched_switch func,
We may utilize event option.(e.g: trace-cmd list -e | grep sched)
This patch is based on Linux-3.3.rc2-SMP-PREEMPT

Link: http://lkml.kernel.org/r/1328695537-15081-1-git-send-email-geunsik.lim@gmail.com

Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Geunsik Lim <geunsik.lim@samsung.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-13 09:14:47 -05:00
Linus Torvalds
3ec1e88b33 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Says Jens:

 "Time to push off some of the pending items.  I really wanted to wait
  until we had the regression nailed, but alas it's not quite there yet.
  But I'm very confident that it's "just" a missing expire on exit, so
  fix from Tejun should be fairly trivial.  I'm headed out for a week on
  the slopes.

  - Killing the barrier part of mtip32xx.  It doesn't really support
    barriers, and it doesn't need them (writes are fully ordered).

  - A few fixes from Dan Carpenter, preventing overflows of integer
    multiplication.

  - A fixup for loop, fixing a previous commit that didn't quite solve
    the partial read problem from Dave Young.

  - A bio integer overflow fix from Kent Overstreet.

  - Improvement/fix of the door "keep locked" part of the cdrom shared
    code from Paolo Benzini.

  - A few cfq fixes from Shaohua Li.

  - A fix for bsg sysfs warning when removing a file it did not create
    from Stanislaw Gruszka.

  - Two fixes for floppy from Vivek, preventing a crash.

  - A few block core fixes from Tejun.  One killing the over-optimized
    ioc exit path, cleaning that up nicely.  Two others fixing an oops
    on elevator switch, due to calling into the scheduler merge check
    code without holding the queue lock."

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: fix lockdep warning on io_context release put_io_context()
  relay: prevent integer overflow in relay_open()
  loop: zero fill bio instead of return -EIO for partial read
  bio: don't overflow in bio_get_nr_vecs()
  floppy: Fix a crash during rmmod
  floppy: Cleanup disk->queue before caling put_disk() if add_disk() was never called
  cdrom: move shared static to cdrom_device_info
  bsg: fix sysfs link remove warning
  block: don't call elevator callbacks for plug merges
  block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions
  mtip32xx: removed the irrelevant argument of mtip_hw_submit_io() and the unused member of struct driver_data
  block: strip out locking optimization in put_io_context()
  cdrom: use copy_to_user() without the underscores
  block: fix ioc locking warning
  block: fix NULL icq_cache reference
  block,cfq: change code order
2012-02-11 10:07:11 -08:00
Fernando Luis Vázquez Cao
86f5e6a7b1 watchdog: Fix code/comments mismatches
Reflect the change in the soft and hard lockup thresholds and
their relation to the frequency of the hrtimer and NMI events in
the code comments. While at it, remove references to files that
do not exist anymore.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1328827342-6253-3-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-11 15:11:33 +01:00
Linus Torvalds
ce2814f227 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix double start/stop in x86_pmu_start()
  perf evsel: Fix an issue where perf report fails to show the proper percentage
  perf tools: Fix prefix matching for kernel maps
  perf tools: Fix perf stack to non executable on x86_64
  perf: Remove deprecated WARN_ON_ONCE()
2012-02-10 09:05:07 -08:00
Dan Carpenter
f6302f1bcd relay: prevent integer overflow in relay_open()
"subbuf_size" and "n_subbufs" come from the user and they need to be
capped to prevent an integer overflow.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-10 09:04:49 +01:00
Srivatsa S. Bhat
a556d5b583 PM / Hibernate: Refactor and simplify freezer_test_done
The code related to 'freezer_test_done' is needlessly convoluted.
Refactor the code and simplify the implementation.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-09 23:56:01 +01:00
Srivatsa S. Bhat
51d6ff7acd PM / Hibernate: Thaw kernel threads in hibernation_snapshot() in error/test path
In the hibernation call path, the kernel threads are frozen inside
hibernation_snapshot(). If we happen to encounter an error further down
the road or if we are exiting early due to a successful freezer test,
then thaw kernel threads before returning to the caller.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-09 23:55:54 +01:00
Marcos Paulo de Souza
8916e3702e PM / Suspend: Avoid code duplication in suspend statistics update
The code
       if (error) {
               suspend_stats.fail++;
               dpm_save_failed_errno(error);
       } else
               suspend_stats.success++;

Appears in the kernel/power/main.c and kernel/power/suspend.c.

This patch just creates a new function to avoid duplicated code.

Suggested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Marcos Paulo de Souza <marcos.mage@gmail.com>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-09 23:55:43 +01:00
Rafael J. Wysocki
3ed3c7b559 Merge commit 'pm-fixes-for-3.3-rc3' into pm-sleep
New material in the pm-sleep branch depends on recent
power management fixes.
2012-02-09 23:54:09 +01:00
Kees Cook
1a2a4d06e1 security: create task_free security callback
The current LSM interface to cred_free is not sufficient for allowing
an LSM to track the life and death of a task. This patch adds the
task_free hook so that an LSM can clean up resources on task death.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-10 09:14:51 +11:00
Stephane Eranian
f39d47ff81 perf: Fix double start/stop in x86_pmu_start()
The following patch fixes a bug introduced by the following
commit:

        e050e3f0a7 ("perf: Fix broken interrupt rate throttling")

The patch caused the following warning to pop up depending on
the sampling frequency adjustments:

  ------------[ cut here ]------------
  WARNING: at arch/x86/kernel/cpu/perf_event.c:995 x86_pmu_start+0x79/0xd4()

It was caused by the following call sequence:

perf_adjust_freq_unthr_context.part() {
     stop()
     if (delta > 0) {
          perf_adjust_period() {
              if (period > 8*...) {
                  stop()
                  ...
                  start()
              }
          }
      }
      start()
}

Which caused a double start and a double stop, thus triggering
the assert in x86_pmu_start().

The patch fixes the problem by avoiding the double calls. We
pass a new argument to perf_adjust_period() to indicate whether
or not the event is already stopped. We can't just remove the
start/stop from that function because it's called from
__perf_event_overflow where the event needs to be reloaded via a
stop/start back-toback call.

The patch reintroduces the assertion in x86_pmu_start() which
was removed by commit:

	84f2b9b ("perf: Remove deprecated WARN_ON_ONCE()")

In this second version, we've added calls to disable/enable PMU
during unthrottling or frequency adjustment based on bug report
of spurious NMI interrupts from Eric Dumazet.

Reported-and-tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: markus@trippelsdorf.de
Cc: paulus@samba.org
Link: http://lkml.kernel.org/r/20120207133956.GA4932@quad
[ Minor edits to the changelog and to the code ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-07 16:58:56 +01:00
Tejun Heo
11a3122f6c block: strip out locking optimization in put_io_context()
put_io_context() performed a complex trylock dancing to avoid
deferring ioc release to workqueue.  It was also broken on UP because
trylock was always assumed to succeed which resulted in unbalanced
preemption count.

While there are ways to fix the UP breakage, even the most
pathological microbench (forced ioc allocation and tight fork/exit
loop) fails to show any appreciable performance benefit of the
optimization.  Strip it out.  If there turns out to be workloads which
are affected by this change, simpler optimization from the discussion
thread can be applied later.

Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <1328514611.21268.66.camel@sli10-conroe>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-07 07:51:30 +01:00
Arnaldo Carvalho de Melo
5ddf146f70 Merge branch 'perf/urgent' into perf/core
So that we can get the perf bench exec stack fixes and then apply the
remaining fix for the files added after what is in perf/urgent.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-02-06 19:11:02 -02:00
Linus Torvalds
23783f817b Power management fixes for 3.3-rc3
Three power management regression fixes, one for a recent regression introcuded
 by the freezer changes during the 3.3 merge window and two for regressions
 in cpuidle (resulting from PM QoS changes) and in the hibernate user space
 interface, both introduced during the 3.2 development cycle.
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Merge tag 'pm-fixes-for-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Power management fixes for 3.3-rc3

Three power management regression fixes, one for a recent regression introcuded
by the freezer changes during the 3.3 merge window and two for regressions
in cpuidle (resulting from PM QoS changes) and in the hibernate user space
interface, both introduced during the 3.2 development cycle.

They include:

* Two hibernate (s2disk) regression fixes from Srivatsa S. Bhat (for
 regressions introduced during the 3.3 merge window and during the 3.2
 development cycle).

* A cpuidle fix from Venki Pallipadi for a regression resulting from PM QoS
 changes during the 3.2 development cycle causing cpuidle to work incorrectly
 for CONFIG_PM unset.

* tag 'pm-fixes-for-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / QoS: CPU C-state breakage with PM Qos change
  PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails
  PM / Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl path
2012-02-04 15:21:39 -08:00
Srivatsa S. Bhat
379e0be812 PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails
If freezing of kernel threads fails, we are expected to automatically
thaw tasks in the error recovery path. However, at times, we encounter
situations in which we would like the automatic error recovery path
to thaw only the kernel threads, because we want to be able to do
some more cleanup before we thaw userspace. Something like:

error = freeze_kernel_threads();
if (error) {
	/* Do some cleanup */

	/* Only then thaw userspace tasks*/
	thaw_processes();
}

An example of such a situation is where we freeze/thaw filesystems
during suspend/hibernation. There, if freezing of kernel threads
fails, we would like to thaw the frozen filesystems before thawing
the userspace tasks.

So, modify freeze_kernel_threads() to thaw only kernel threads in
case of freezing failure. And change suspend_freeze_processes()
accordingly. (At the same time, let us also get rid of the rather
cryptic usage of the conditional operator (:?) in that function.)

[rjw: In fact, this patch fixes a regression introduced during the
 3.3 merge window, because without it thaw_processes() may be called
 before swsusp_free() in some situations and that may lead to massive
 memory allocation failures.]

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Nigel Cunningham <nigel@tuxonice.net>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-04 22:23:05 +01:00
Jiang Liu
55ca6140e9 kprobes: fix a memory leak in function pre_handler_kretprobe()
In function pre_handler_kretprobe(), the allocated kretprobe_instance
object will get leaked if the entry_handler callback returns non-zero.
This may cause all the preallocated kretprobe_instance objects exhausted.

This issue can be reproduced by changing
samples/kprobes/kretprobe_example.c to probe "mutex_unlock".  And the fix
is straightforward: just put the allocated kretprobe_instance object back
onto the free_instances list.

[akpm@linux-foundation.org: use raw_spin_lock/unlock]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-03 16:16:41 -08:00
Cong Wang
2410574866 kernel/resource.c: move EXPORT_SYMBOL right after definition
EXPORT_SYMBOL(adjust_resource) should be right after adjust_resource().

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-02-03 23:37:07 +01:00
Steven Rostedt
f069686e4b tracing/softirq: Move __raise_softirq_irqoff() out of header
The __raise_softirq_irqoff() contains a tracepoint. As tracepoints in headers
can cause issues, and not to mention, bloats the kernel when they are
in a static inline, it is best to move the function that contains the
tracepoint out of the header and into softirq.c.

Link: http://lkml.kernel.org/r/20120118120711.GB14863@elte.hu

Suggested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-03 09:48:19 -05:00
Jiri Olsa
ac483c446b ftrace: Change filter/notrace set functions to return exit code
Currently the ftrace_set_filter and ftrace_set_notrace functions
do not return any return code. So there's no way for ftrace_ops
user to tell wether the filter was correctly applied.

The set_ftrace_filter interface returns error in case the filter
did not match:

  # echo krava > set_ftrace_filter
  bash: echo: write error: Invalid argument

Changing both ftrace_set_filter and ftrace_set_notrace functions
to return zero if the filter was applied correctly or -E* values
in case of error.

Link: http://lkml.kernel.org/r/1325495060-6402-2-git-send-email-jolsa@redhat.com

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-03 09:48:18 -05:00
Christopher Yeoh
8cdb878dcb Fix race in process_vm_rw_core
This fixes the race in process_vm_core found by Oleg (see

  http://article.gmane.org/gmane.linux.kernel/1235667/

for details).

This has been updated since I last sent it as the creation of the new
mm_access() function did almost exactly the same thing as parts of the
previous version of this patch did.

In order to use mm_access() even when /proc isn't enabled, we move it to
kernel/fork.c where other related process mm access functions already
are.

Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-02 12:55:17 -08:00
Linus Torvalds
2f2fde9272 Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus', 'sched-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  bugs, x86: Fix printk levels for panic, softlockups and stack dumps

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf top: Fix number of samples displayed
  perf tools: Fix strlen() bug in perf_event__synthesize_event_type()
  perf tools: Fix broken build by defining _GNU_SOURCE in Makefile
  x86/dumpstack: Remove unneeded check in dump_trace()
  perf: Fix broken interrupt rate throttling

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Fix task stack corruption under __ARCH_WANT_INTERRUPTS_ON_CTXSW
  sched: Fix ancient race in do_exit()
  sched/nohz: Fix nohz cpu idle load balancing state with cpu hotplug
  sched/s390: Fix compile error in sched/core.c
  sched: Fix rq->nr_uninterruptible update race

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/reboot: Remove VersaLogic Menlow reboot quirk
  x86/reboot: Skip DMI checks if reboot set by user
  x86: Properly parenthesize cmpxchg() macro arguments
2012-02-02 11:11:13 -08:00
Li Zefan
761b3ef50e cgroup: remove cgroup_subsys argument from callbacks
The argument is not used at all, and it's not necessary, because
a specific callback handler of course knows which subsys it
belongs to.

Now only ->pupulate() takes this argument, because the handlers of
this callback always call cgroup_add_file()/cgroup_add_files().

So we reduce a few lines of code, though the shrinking of object size
is minimal.

 16 files changed, 113 insertions(+), 162 deletions(-)

   text    data     bss     dec     hex filename
5486240  656987 7039960 13183187         c928d3 vmlinux.o.orig
5486170  656987 7039960 13183117         c9288d vmlinux.o

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2012-02-02 09:20:22 -08:00
Srivatsa S. Bhat
fe9161db2e PM / Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl path
In the SNAPSHOT_CREATE_IMAGE ioctl, if the call to hibernation_snapshot()
fails, the frozen tasks are not thawed.

And in the case of success, if we happen to exit due to a successful freezer
test, all tasks (including those of userspace) are thawed, whereas actually
we should have thawed only the kernel threads at that point. Fix both these
issues.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: stable@vger.kernel.org
2012-02-01 22:16:36 +01:00
Hiroshi Shimamoto
ed387b781e sched: Move SMP-only variable into the SMP section
This also fixes the following compilation warning on !SMP:

  CC kernel/sched/fair.o
  kernel/sched/fair.c:218:36: warning: 'max_load_balance_interval' defined but not used [-Wunused-variable]

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4F2754A0.9090306@ct.jp.nec.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-31 13:40:59 +01:00
Ingo Molnar
bb1693f89a Merge branch 'perf/urgent' into perf/core
We cherry-picked 3 commits into perf/urgent, merge them back to allow
conflict-free work on those files.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-31 13:02:37 +01:00
Mandeep Singh Baines
61d1d219c4 cgroup: remove extra calls to find_existing_css_set
In cgroup_attach_proc, we indirectly call find_existing_css_set 3
times. It is an expensive call so we want to call it a minimum
of times. This patch only calls it once and stores the result so
that it can be used later on when we call cgroup_task_migrate.

This required modifying cgroup_task_migrate to take the new css_set
(which we obtained from find_css_set) as a parameter. The nice side
effect of this is that cgroup_task_migrate is now identical for
cgroup_attach_task and cgroup_attach_proc. It also now returns a
void since it can never fail.

Changes in V5:
* https://lkml.org/lkml/2012/1/20/344 (Tejun Heo)
  * Remove css_set_refs
Changes in V4:
* https://lkml.org/lkml/2011/12/22/421 (Li Zefan)
  * Avoid GFP_KERNEL (sleep) in rcu_read_lock by getting css_set in
    a separate loop not under an rcu_read_lock
Changes in V3:
* https://lkml.org/lkml/2011/12/22/13 (Li Zefan)
  * Fixed earlier bug by creating a seperate patch to remove tasklist_lock
Changes in V2:
* https://lkml.org/lkml/2011/12/20/372 (Tejun Heo)
  * Move find_css_set call into loop which creates the flex array
* Author
  * Kill css_set_refs and use group_size instead
  * Fix an off-by-one error in counting css_set refs
  * Add a retval check in out_list_teardown

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: containers@lists.linux-foundation.org
Cc: cgroups@vger.kernel.org
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Menage <paul@paulmenage.org>
2012-01-30 13:01:39 -08:00