Commit Graph

10322 Commits (c28d5077f8d79bfce1e3f88db2e261cf2b6473dc)

Author SHA1 Message Date
Steven Rostedt 72441cb1fd ftrace/x86: Add support for C version of recordmcount
This patch adds the support for the C version of recordmcount and
compile times show ~ 12% improvement.

After verifying this works, other archs can add:

 HAVE_C_MCOUNT_RECORD

in its Kconfig and it will use the C version of recordmcount
instead of the perl version.

Cc: <linux-arch@vger.kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kbuild@vger.kernel.org
Cc: John Reiser <jreiser@bitwagon.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-10-14 16:52:41 -04:00
Masami Hiramatsu fd02e6f7ae kprobes: Fix selftest to clear flags field for reusing probes
Fix selftest to clear flags field for reusing probes
because the flags field can be modified by Kprobes.
This also set NULL to kprobe.addr instead of 0.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: 2nddept-manager@sdl.hitachi.co.jp
LKML-Reference: <20101014031024.4100.50107.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-14 08:55:27 +02:00
Ingo Molnar 7cd2541cf2 Merge commit 'v2.6.36-rc7' into perf/core
Conflicts:
	arch/x86/kernel/module.c

Merge reason: Resolve the conflict, pick up fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-08 10:46:27 +02:00
Linus Torvalds e1d9694cae Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: rcu_read_lock_bh_held(): disabling irqs also disables bh
  generic-ipi: Fix deadlock in __smp_call_function_single
2010-10-05 13:07:43 -07:00
Linus Torvalds 5336377d62 modules: Fix module_bug_list list corruption race
With all the recent module loading cleanups, we've minimized the code
that sits under module_mutex, fixing various deadlocks and making it
possible to do most of the module loading in parallel.

However, that whole conversion totally missed the rather obscure code
that adds a new module to the list for BUG() handling.  That code was
doubly obscure because (a) the code itself lives in lib/bugs.c (for
dubious reasons) and (b) it gets called from the architecture-specific
"module_finalize()" rather than from generic code.

Calling it from arch-specific code makes no sense what-so-ever to begin
with, and is now actively wrong since that code isn't protected by the
module loading lock any more.

So this commit moves the "module_bug_{finalize,cleanup}()" calls away
from the arch-specific code, and into the generic code - and in the
process protects it with the module_mutex so that the list operations
are now safe.

Future fixups:
 - move the module list handling code into kernel/module.c where it
   belongs.
 - get rid of 'module_bug_list' and just use the regular list of modules
   (called 'modules' - imagine that) that we already create and maintain
   for other reasons.

Reported-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Adrian Bunk <bunk@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-05 11:29:27 -07:00
Stephane Eranian 540804b5c5 perf_events: Fix invalid pointer when pid is invalid
This patch fixes an error in perf_event_open() when the pid
provided by the user is invalid. find_lively_task_by_vpid()
does not return NULL on error but an error code. Without the
fix the error code was silently passed to find_get_context()
which would eventually cause a invalid pointer dereference.

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Cc: paulus@samba.org
Cc: davem@davemloft.net
Cc: fweisbec@gmail.com
Cc: perfmon2-devel@lists.sf.net
Cc: eranian@gmail.com
Cc: robert.richter@amd.com
LKML-Reference: <4ca9a5d1.e8e9d80a.3dbb.ffff8f2e@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-04 12:47:20 +02:00
Ira W. Snyder 399f1e30ac kfifo: fix scatterlist usage
The kfifo_dma family of functions use sg_mark_end() on the last element in
their scatterlist.  This forces use of a fresh scatterlist for each DMA
operation, which makes recycling a single scatterlist impossible.

Change the behavior of the kfifo_dma functions to match the usage of the
dma_map_sg function.  This means that users must respect the returned
nents value.  The sample code is updated to reflect the change.

This bug is trivial to cause: call kfifo_dma_in_prepare() such that it
prepares a scatterlist with a single entry comprising the whole fifo.
This is the case when you map the entirety of a newly created empty fifo.
This causes the setup_sgl() function to mark the first scatterlist entry
as the end of the chain, no matter what comes after it.

Afterwards, add and remove some data from the fifo such that another call
to kfifo_dma_in_prepare() will create two scatterlist entries.  It returns
nents=2.  However, due to the previous sg_mark_end() call, sg_is_last()
will now return true for the first scatterlist element.  This causes the
sample code to print a single scatterlist element when it should print
two.

By removing the call to sg_mark_end(), we make the API as similar as
possible to the DMA mapping API.  All users are required to respect the
returned nents.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Cc: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-01 10:50:58 -07:00
Ingo Molnar a5a2bad55d Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core 2010-09-24 09:12:05 +02:00
Andrea Arcangeli a247c3a97a rmap: fix walk during fork
The below bug in fork led to the rmap walk finding the parent huge-pmd
twice instead of just once, because the anon_vma_chain objects of the
child vma still point to the vma->vm_mm of the parent.

The patch fixes it by making the rmap walk accurate during fork.  It's not
a big deal normally but it worth being accurate considering the cost is
the same.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Johannes Weiner <jweiner@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-22 17:22:39 -07:00
Jason Baron 8f7b50c514 jump label: Tracepoint support for jump labels
Make use of the jump label infrastructure for tracepoints.

Signed-off-by: Jason Baron <jbaron@redhat.com>
LKML-Reference: <a9ba2056e2c9cf332c3c300b577463ce66ff23a8.1284733808.git.jbaron@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-22 16:31:01 -04:00
Jason Baron 4c3ef6d793 jump label: Add jump_label_text_reserved() to reserve jump points
Add a jump_label_text_reserved(void *start, void *end), so that other
pieces of code that want to modify kernel text, can first verify that
jump label has not reserved the instruction.

Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
LKML-Reference: <06236663a3a7b1c1f13576bb9eccb6d9c17b7bfe.1284733808.git.jbaron@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-22 16:30:46 -04:00
Jason Baron e0cf0cd496 jump label: Initialize workqueue tracepoints *before* they are registered
Initialize the workqueue data structures *before* they are registered
so that they are ready for callbacks.

Signed-off-by: Jason Baron <jbaron@redhat.com>
LKML-Reference: <e3a3383fc370ac7086625bebe89d9480d7caf372.1284733808.git.jbaron@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-22 16:30:03 -04:00
Jason Baron bf5438fca2 jump label: Base patch for jump label
base patch to implement 'jump labeling'. Based on a new 'asm goto' inline
assembly gcc mechanism, we can now branch to labels from an 'asm goto'
statment. This allows us to create a 'no-op' fastpath, which can subsequently
be patched with a jump to the slowpath code. This is useful for code which
might be rarely used, but which we'd like to be able to call, if needed.
Tracepoints are the current usecase that these are being implemented for.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jason Baron <jbaron@redhat.com>
LKML-Reference: <ee8b3595967989fdaf84e698dc7447d315ce972a.1284733808.git.jbaron@redhat.com>

[ cleaned up some formating ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-22 16:29:41 -04:00
Ingo Molnar 90edf27fb8 Merge branch 'linus' into perf/core
Conflicts:
	kernel/hw_breakpoint.c

Merge reason: resolve the conflict.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-22 18:45:01 +02:00
Linus Torvalds 1ce1e41c1b Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix nohz balance kick
  sched: Fix user time incorrectly accounted as system time on 32-bit
2010-09-21 13:22:10 -07:00
Linus Torvalds 87ac6fa26e Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hw breakpoints: Fix pid namespace bug
  x86: Fix instruction breakpoint encoding
  oprofile: Add Support for Intel CPU Family 6 / Model 22 (Intel Celeron 540)
  kprobes: Fix Kconfig dependency
2010-09-21 13:21:42 -07:00
Peter Zijlstra 41945f6ccf perf: Avoid RCU vs preemption assumptions
The per-pmu per-cpu context patch converted things from
get_cpu_var() to this_cpu_ptr(), but that only works if
rcu_read_lock() actually disables preemption, and since
there is no such guarantee, we need to fix that.

Use the newly introduced {get,put}_cpu_ptr().

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>
LKML-Reference: <20100917093009.308453028@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-21 13:55:44 +02:00
Ingo Molnar 7ed569206e Merge commit 'v2.6.36-rc5' into perf/core
Merge reason: Pick up the latest fixes in -rc5.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-21 13:55:11 +02:00
Suresh Siddha f6c3f1686e sched: Fix nohz balance kick
There's a situation where the nohz balancer will try to wake itself:

cpu-x is idle which is also ilb_cpu
got a scheduler tick during idle
and the nohz_kick_needed() in trigger_load_balance() checks for
rq_x->nr_running which might not be zero (because of someone waking a
task on this rq etc) and this leads to the situation of the cpu-x
sending a kick to itself.

And this can cause a lockup.

Avoid this by not marking ourself eligible for kicking.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1284400941.2684.19.camel@sbsiddha-MOBL3.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-21 13:50:50 +02:00
Peter Zijlstra e9d2b06414 perf: Undo the per cpu-context timer stuff
Revert the timer per cpu-context timers because of unfortunate
nohz interaction. Fixing that would have been somewhat ugly, so
go back to driving things from the regular tick. Provide a
jiffies interval feature for people who want slower rotations.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20100917093009.519845633@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-17 12:48:48 +02:00
Peter Zijlstra 917bdd1c9b perf: Fix perf_event_exit_cpu_context()
Use the right cpu-context.. spotted by preempt warning on
hot-unplug

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
LKML-Reference: <20100917093009.461794357@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-17 12:48:48 +02:00
Peter Zijlstra b04243ef70 perf: Complete software pmu grouping
Aside from allowing software events into a !software group,
allow adding !software events to pure software groups.

Once we've moved the software group and attached the first
!software event, the group will no longer be a pure software
group and hence no longer be eligible for movement, at which
point the straight ctx comparison is correct again.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20100917093009.410784731@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-17 12:48:48 +02:00
Stephane Eranian d14b12d7ad perf_events: Fix broken event grouping
Events were not grouped anymore. The reason was that in
perf_event_open(), the field event->group_leader was
initialized before the function looked up the group_fd
to find the event leader. This patch fixes this by
reordering the code correctly.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
LKML-Reference: <20100917093009.360420946@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-17 12:48:47 +02:00
Matt Helsley 068e35eee9 hw breakpoints: Fix pid namespace bug
Hardware breakpoints can't be registered within pid namespaces
because tsk->pid is passed rather than the pid in the current
namespace.

(See https://bugzilla.kernel.org/show_bug.cgi?id=17281 )

This is a quick fix demonstrating the problem but is not the
best method of solving the problem since passing pids internally
is not the best way to avoid pid namespace bugs. Subsequent patches
will show a better solution.

Much thanks to Frederic Weisbecker <fweisbec@gmail.com> for doing
the bulk of the work finding this bug.

Reported-by: Robin Green <greenrd@greenrd.org>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Cc: 2.6.33-2.6.35 <stable@kernel.org>
LKML-Reference: <f63454af09fb1915717251570423eb9ddd338340.1284407762.git.matthltc@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-09-17 04:42:59 +02:00
Linus Torvalds 94ca9d669a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: add documentation
2010-09-16 12:50:31 -07:00
Namhyung Kim 635c17c2b2 kprobes: Add sparse context annotations
This removes following warnings when build with C=1

 warning: context imbalance in 'kretprobe_hash_lock' - wrong count at exit
 warning: context imbalance in 'kretprobe_table_lock' - wrong count at exit
 warning: context imbalance in 'kretprobe_hash_unlock' - unexpected unlock
 warning: context imbalance in 'kretprobe_table_unlock' - unexpected unlock

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1284512670-2369-6-git-send-email-namhyung@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-15 10:44:02 +02:00
Namhyung Kim 6376b22975 kprobes: Make functions static
Make following (internal) functions static to make sparse
happier :-)

 * get_optimized_kprobe: only called from static functions
 * kretprobe_table_unlock: _lock function is static
 * kprobes_optinsn_template_holder: never called but holding asm code

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1284512670-2369-4-git-send-email-namhyung@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-15 10:44:01 +02:00
Namhyung Kim 05662bdb64 kprobes: Verify jprobe entry point
Verify jprobe's entry point is a function entry point
using kallsyms' offset value.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1284512670-2369-3-git-send-email-namhyung@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-15 10:44:01 +02:00
Namhyung Kim edbaadbe42 kprobes: Remove redundant address check
Remove call to kernel_text_address() in register_jprobes()
because it is called right after in register_kprobe().

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
LKML-Reference: <1284512670-2369-2-git-send-email-namhyung@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-15 10:44:00 +02:00
Matt Helsley 38a81da220 perf events: Clean up pid passing
The kernel perf event creation path shouldn't use find_task_by_vpid()
because a vpid exists in a specific namespace. find_task_by_vpid() uses
current's pid namespace which isn't always the correct namespace to use
for the vpid in all the places perf_event_create_kernel_counter() (and
thus find_get_context()) is called.

The goal is to clean up pid namespace handling and prevent bugs like:

	https://bugzilla.kernel.org/show_bug.cgi?id=17281

Instead of using pids switch find_get_context() to use task struct
pointers directly. The syscall is responsible for resolving the pid to
a task struct. This moves the pid namespace resolution into the syscall
much like every other syscall that takes pid parameters.

Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robin Green <greenrd@greenrd.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
LKML-Reference: <a134e5e392ab0204961fd1a62c84a222bf5874a9.1284407763.git.matthltc@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-15 10:44:00 +02:00
Matt Helsley 2ebd4ffb6d perf events: Split out task search into helper
Split out the code which searches for non-exiting tasks into its own
helper. Creating this helper not only makes the code slightly more
readable it prepares to move the search out of find_get_context() in
a subsequent commit.

Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robin Green <greenrd@greenrd.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
LKML-Reference: <561205417b450b8a4bf7488374541d64b4690431.1284407762.git.matthltc@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-15 10:44:00 +02:00
Matt Helsley d958077d00 hw breakpoints: Fix pid namespace bug
Hardware breakpoints can't be registered within pid namespaces
because tsk->pid is passed rather than the pid in the current
namespace.

(See https://bugzilla.kernel.org/show_bug.cgi?id=17281 )

This is a quick fix demonstrating the problem but is not the
best method of solving the problem since passing pids internally
is not the best way to avoid pid namespace bugs. Subsequent patches
will show a better solution.

Much thanks to Frederic Weisbecker <fweisbec@gmail.com> for doing the
bulk of the work finding this bug.

Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robin Green <greenrd@greenrd.org>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
LKML-Reference: <f63454af09fb1915717251570423eb9ddd338340.1284407762.git.matthltc@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-15 10:43:59 +02:00
Stephane Eranian d9ca07a05c watchdog: Avoid kernel crash when disabling watchdog
In case you boot with the watchdog disabled, i.e., nowatchdog, then,
if you try to disable it via /proc/sys/kernel/watchdog, you get
a kernel crash. The reason is that you are trying to cancel a hrtimer
which has never been initialized.

This patch fixes this by skipping execution of
watchdog_disable_all_cpus() when the watchdog is marked
disabled from boot.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4c8f7a23.cae9d80a.2c11.0bb4@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-15 10:43:58 +02:00
Stanislaw Gruszka e75e863dd5 sched: Fix user time incorrectly accounted as system time on 32-bit
We have 32-bit variable overflow possibility when multiply in
task_times() and thread_group_times() functions. When the
overflow happens then the scaled utime value becomes erroneously
small and the scaled stime becomes i erroneously big.

Reported here:

 https://bugzilla.redhat.com/show_bug.cgi?id=633037
 https://bugzilla.kernel.org/show_bug.cgi?id=16559

Reported-by: Michael Chapman <redhat-bugzilla@very.puzzling.org>
Reported-by: Ciriaco Garcia de Celis <sysman@etherpilot.com>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: <stable@kernel.org>  # 2.6.32.19+ (partially) and 2.6.33+
LKML-Reference: <20100914143513.GB8415@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-15 10:41:36 +02:00
Ingo Molnar 3aabae7d9d Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core 2010-09-15 10:27:31 +02:00
Steven Rostedt 79e406d7b0 tracing: Remove leftover FTRACE_ENABLE/DISABLE_MCOUNT enums
The enums for FTRACE_ENABLE_MCOUNT and FTRACE_DISABLE_MCOUNT were
used as commands to ftrace_run_update_code(). But these commands
were used by the old nasty ftrace daemon that has long been slain.

This is a clean up patch to remove the references to these enums
and simplify the code a little.

Reported-by: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-14 22:19:46 -04:00
Steven Rostedt b304d0441a tracing: Do not trace in irq when funcgraph-irq option is zero
When the function graph tracer funcgraph-irq option is zero, disable
tracing in IRQs. This makes the option have two effects.

1) When reading the trace file, do not display the functions that
   happen in interrupt context (when detected)

2) [*new*] When recording a trace, skip those that are detected
   to be in interrupt by the 'in_irq()' function

Note, in_irq() is updated at irq_enter() and irq_exit(). There are
still functions that are recorded by the function graph tracer that
is in interrupt context but outside the irq_enter/exit() routines.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-14 20:18:07 -04:00
Jiri Olsa 2bd16212b8 tracing: Add funcgraph-irq option for function graph tracer.
It's handy to be able to disable the irq related output
and not to have to jump over each irq related code, when
you have no interrest in it.

The option is by default enabled, so there's no change to
current behaviour. It affects only the final output, so all
the irq related data stay in the ring buffer.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <20100907145344.GC1912@jolsa.brq.redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-14 20:18:07 -04:00
H. Peter Anvin c41d68a513 compat: Make compat_alloc_user_space() incorporate the access_ok()
compat_alloc_user_space() expects the caller to independently call
access_ok() to verify the returned area.  A missing call could
introduce problems on some architectures.

This patch incorporates the access_ok() check into
compat_alloc_user_space() and also adds a sanity check on the length.
The existing compat_alloc_user_space() implementations are renamed
arch_compat_alloc_user_space() and are used as part of the
implementation of the new global function.

This patch assumes NULL will cause __get_user()/__put_user() to either
fail or access userspace on all architectures.  This should be
followed by checking the return value of compat_access_user_space()
for NULL in the callers, at which time the access_ok() in the callers
can also be removed.

Reported-by: Ben Hawkes <hawkes@sota.gen.nz>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: James Bottomley <jejb@parisc-linux.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: <stable@kernel.org>
2010-09-14 16:08:45 -07:00
Steven Rostedt 57c072c711 tracing: Fix reading of set_ftrace_filter across lists
If we do:

 # cd /sys/kernel/debug
 # echo 'do_IRQ:traceon schedule:traceon sys_write:traceon' > \
    set_ftrace_filter
 # cat set_ftrace_filter

We get the following output:

 #### all functions enabled ####
 sys_write:traceon:unlimited
 schedule:traceon:unlimited
 do_IRQ:traceon:unlimited

This outputs two lists. One is the fact that all functions are
currently enabled for function tracing, the other has three probed
functions, which happen to have 'traceon' as their commands.

Currently, when reading the first list (functions enabled) the
seq_file code will receive a "NULL" from the t_next() function
causing it to exit early. This makes "read()" from userspace stop
reading the code at this boarder. Although read is allowed to do this,
some (broken) applications might consider this an end of file and
stop early.

This patch adds the start of the second list to t_next() when it
finishes the first list. It is a simple change and gives the
set_ftrace_filter file nicer reading ability.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-14 15:14:20 -04:00
Steven Rostedt 98c4fd046f tracing: Keep track of set_ftrace_filter position and allow lseek again
This patch keeps track of the index within the elements of
set_ftrace_filter and if the position goes backwards, it nicely
resets and starts from the beginning again.

This allows for lseek and pread to work properly now.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-14 14:46:01 -04:00
Steven Rostedt 4aeb69672d tracing: Replace typecasted void pointer in set_ftrace_filter code
The set_ftrace_filter uses seq_file and reads from two lists. The
pointer returned by t_next() can either be of type struct dyn_ftrace
or struct ftrace_func_probe. If there is a bug (there was one)
the wrong pointer may be used and the reference can cause an oops.

This patch makes t_next() and friends only return the iterator structure
which now has a pointer of type struct dyn_ftrace and struct
ftrace_func_probe. The t_show() can now test if the pointer is NULL or
not and if the pointer exists, it is guaranteed to be of the correct type.

Now if there's a bug, only wrong data will be shown but not an oops.

Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-14 11:42:30 -04:00
Steven Rostedt 2bccfffd15 tracing: Do not reset *pos in set_ftrace_filter
After the filtered functions are read, the probed functions are read
from the hash in set_ftrace_filter. When the hashed probed functions
are read, the *pos passed in is reset. Instead of modifying the pos
given to the read function, just record the pos where the filtered
functions ended and subtract from that.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-09-14 11:42:29 -04:00
Ingo Molnar 0bf377bbb0 sched: Improve latencies under load by decreasing minimum scheduling granularity
Mathieu reported bad latencies with make -j10 kind of kbuild
workloads - which is mostly caused by us scheduling with a
too coarse granularity.

Reduce the minimum granularity some more, to make sure we
can meet the latency target.

I got the following results (make -j10 kbuild load, average of 3
runs):

 vanilla:

  maximum latency: 38278.9 µs
  average latency:  7730.1 µs

 patched:

  maximum latency: 22702.1 µs
  average latency:  6684.8 µs

Mathieu also measured it:

|
| * wakeup-latency.c (SIGEV_THREAD) with make -j10
|
| - Mainline 2.6.35.2 kernel
|
| maximum latency: 45762.1 µs
| average latency: 7348.6 µs
|
| - With only Peter's smaller min_gran (shown below):
|
| maximum latency: 29100.6 µs
| average latency: 6684.1 µs
|

Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <AANLkTi=8m4g01wZPacySoF7U0PevTNVgJoZZrHiUD-pN@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-13 20:17:11 +02:00
Peter Zijlstra 0c67b40872 perf: Fix free_event()
With the context rework stuff we can actually end up freeing an event
before it gets attached to a context.

Reported-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-13 17:08:42 +02:00
Peter Zijlstra cde8e88498 perf: Sanitize the RCU logic
Simplify things and simply synchronize against two RCU variants for
PMU unregister -- we don't care about performance, its module unload
if anything.

Reported-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-09-13 17:08:42 +02:00
Tejun Heo c54fce6eff workqueue: add documentation
Update copyright notice and add Documentation/workqueue.txt.

Randy Dunlap, Dave Chinner: misc fixes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-By: Florian Mickler <florian@mickler.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
2010-09-13 10:26:52 +02:00
Linus Torvalds 84e1d836ef Merge branch 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM / Hibernate: Avoid hitting OOM during preallocation of memory
  PM QoS: Correct pr_debug() misuse and improve parameter checks
  PM: Prevent waiting forever on asynchronous resume after failing suspend
2010-09-11 15:50:53 -07:00
Rafael J. Wysocki 6715045ddc PM / Hibernate: Avoid hitting OOM during preallocation of memory
There is a problem in hibernate_preallocate_memory() that it calls
preallocate_image_memory() with an argument that may be greater than
the total number of available non-highmem memory pages.  If that's
the case, the OOM condition is guaranteed to trigger, which in turn
can cause significant slowdown to occur during hibernation.

To avoid that, make preallocate_image_memory() adjust its argument
before calling preallocate_image_pages(), so that the total number of
saveable non-highem pages left is not less than the minimum size of
a hibernation image.  Change hibernate_preallocate_memory() to try to
allocate from highmem if the number of pages allocated by
preallocate_image_memory() is too low.

Modify free_unnecessary_pages() to take all possible memory
allocation patterns into account.

Reported-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: M. Vefa Bicakci <bicave@superonline.com>
2010-09-11 21:03:53 +02:00
Linus Torvalds aad1830e6b Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, tsc: Fix a preemption leak in restore_sched_clock_state()
  sched: Move sched_avg_update() to update_cpu_load()
2010-09-11 07:59:49 -07:00