Commit Graph

7694 Commits

Author SHA1 Message Date
David S. Miller
31ffe249e5 net: Temporarily backout SKB sources tracer.
Steven Rostedt has suggested that Neil work with the tracing
folks, trying to use TRACE_EVENT as the mechanism for
implementation.  And if that doesn't workout we can investigate
other solutions such as that one which was tried here.

This reverts the following 2 commits:

5a165657be
("net: skb ftracer - Add config option to enable new ftracer (v3)")

9ec04da748
("net: skb ftracer - Add actual ftrace code to kernel (v3)")

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-26 16:32:37 -07:00
Randy Dunlap
3a5209e3b2 trace_skb: fix build when CONFIG_NET is not enabled
Fix trace_skb_sources build when CONFIG_NET is not enabled:

kernel/built-in.o: In function `probe_skb_dequeue':
trace_skb_sources.c:(.text+0xd9152): undefined reference to `init_net'
trace_skb_sources.c:(.text+0xd9188): undefined reference to `dev_get_by_index'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 16:00:30 -07:00
Neil Horman
9ec04da748 net: skb ftracer - Add actual ftrace code to kernel (v3)
skb allocation / consumption correlator

Add ftracer module to kernel to print out a list that correlates a process id,
an skb it read, and the numa nodes on wich the process was running when it was
read along with the numa node the skbuff was allocated on.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

 Makefile            |    1
 trace.h             |   19 ++++++
 trace_skb_sources.c |  154 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 174 insertions(+)
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-13 16:43:25 -07:00
Neil Horman
5a165657be net: skb ftracer - Add config option to enable new ftracer (v3)
skb allocation / consumption corelator - Add config option

This patch adds a Kconfig option to enable the addtition of the skb source
tracer.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

 Kconfig |   10 ++++++++++
 1 file changed, 10 insertions(+)
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-13 16:42:37 -07:00
David S. Miller
aa11d958d1 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	arch/microblaze/include/asm/socket.h
2009-08-12 17:44:53 -07:00
Linus Torvalds
2e9b11afdb Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  posix_cpu_timers_exit_group(): Do not use thread_group_cputimer()
2009-08-09 14:57:41 -07:00
Linus Torvalds
95d0ad049c Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_counter: Fix/complete ftrace event records sampling
  perf_counter, ftrace: Fix perf_counter integration
  tracing/filters: Always free pred on filter_add_subsystem_pred() failure
  tracing/filters: Don't use pred on alloc failure
  ring-buffer: Fix memleak in ring_buffer_free()
  tracing: Fix recordmcount.pl to handle sections with only weak functions
  ring-buffer: Fix advance of reader in rb_buffer_peek()
  tracing: do not use functions starting with .L in recordmcount.pl
  ring-buffer: do not disable ring buffer on oops_in_progress
  ring-buffer: fix check of try_to_discard result
2009-08-09 14:57:26 -07:00
Linus Torvalds
713e3e1875 Merge branch 'core-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  lockdep: Fix typos in documentation
  lockdep: Fix file mode of lock_stat
  rtmutex: Avoid deadlock in rt_mutex_start_proxy_lock()
2009-08-09 14:56:51 -07:00
Frederic Weisbecker
f413cdb80c perf_counter: Fix/complete ftrace event records sampling
This patch implements the kernel side support for ftrace event
record sampling.

A new counter sampling attribute is added:

   PERF_SAMPLE_TP_RECORD

which requests ftrace events record sampling. In this case
if a PERF_TYPE_TRACEPOINT counter is active and a tracepoint
fires, we emit the tracepoint binary record to the
perfcounter event buffer, as a sample.

Result, after setting PERF_SAMPLE_TP_RECORD attribute from perf
record:

 perf record -f -F 1 -a -e workqueue:workqueue_execution
 perf report -D

 0x21e18 [0x48]: event: 9
 .
 . ... raw event: size 72 bytes
 .  0000:  09 00 00 00 01 00 48 00 d0 c7 00 81 ff ff ff ff  ......H........
 .  0010:  0a 00 00 00 0a 00 00 00 21 00 00 00 00 00 00 00  ........!......
 .  0020:  2b 00 01 02 0a 00 00 00 0a 00 00 00 65 76 65 6e  +...........eve
 .  0030:  74 73 2f 31 00 00 00 00 00 00 00 00 0a 00 00 00  ts/1...........
 .  0040:  e0 b1 31 81 ff ff ff ff                          .......
.
0x21e18 [0x48]: PERF_EVENT_SAMPLE (IP, 1): 10: 0xffffffff8100c7d0 period: 33

The raw ftrace binary record starts at offset 0020.

Translation:

 struct trace_entry {
	type		= 0x2b = 43;
	flags		= 1;
	preempt_count	= 2;
	pid		= 0xa = 10;
	tgid		= 0xa = 10;
 }

 thread_comm = "events/1"
 thread_pid  = 0xa = 10;
 func	    = 0xffffffff8131b1e0 = flush_to_ldisc()

What will come next?

 - Userspace support ('perf trace'), 'flight data recorder' mode
   for perf trace, etc.

 - The unconditional copy from the profiling callback brings
   some costs however if someone wants no such sampling to
   occur, and needs to be fixed in the future. For that we need
   to have an instant access to the perf counter attribute.
   This is a matter of a flag to add in the struct ftrace_event.

 - Take care of the events recursivity! Don't ever try to record
   a lock event for example, it seems some locking is used in
   the profiling fast path and lead to a tracing recursivity.
   That will be fixed using raw spinlock or recursivity
   protection.

 - [...]

 - Profit! :-)

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:53:48 +02:00
Peter Zijlstra
3a6593050f perf_counter, ftrace: Fix perf_counter integration
Adds possible second part to the assign argument of TP_EVENT().

  TP_perf_assign(
	__perf_count(foo);
	__perf_addr(bar);
  )

Which, when specified make the swcounter increment with @foo instead
of the usual 1, and report @bar for PERF_SAMPLE_ADDR (data address
associated with the event) when this triggers a counter overflow.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:47:25 +02:00
Ingo Molnar
e3560336be Merge branch 'linus' into tracing/urgent
Merge reason: Merge up to almost-rc6 to pick up latest perfcounters
              (on which we'll queue up a dependent fix)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:46:49 +02:00
Stanislaw Gruszka
17d42c1c49 posix_cpu_timers_exit_group(): Do not use thread_group_cputimer()
When the process exits we don't have to run new cputimer nor
use running one (as it not accounts when tsk->exit_state != 0)
to get process CPU times.  As there is only one thread we can
just use CPU times fields from task and signal structs.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Roland McGrath <roland@redhat.com>
Cc: Vitaly Mayatskikh <vmayatsk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-08 18:30:25 +02:00
Tom Zanussi
26528e773e tracing/filters: Always free pred on filter_add_subsystem_pred() failure
If filter_add_subsystem_pred() fails due to ENOSPC or ENOMEM,
the pred doesn't get freed, while as a side effect it does for
other errors. Make it so the caller always frees the pred for
any error.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <1249746593.6453.32.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-08 17:56:13 +02:00
Tom Zanussi
96b2de313b tracing/filters: Don't use pred on alloc failure
Dan Carpenter sent me a fix to prevent pred from being used if
it couldn't be allocated.  I noticed the same problem also
existed for the create_pred() case and added a fix for that.

Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <1249746549.6453.29.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-08 17:55:34 +02:00
Linus Torvalds
da758ddede Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_counter: Fix double list iteration in per task precise stats
  perf: Auto-detect libelf
  perf symbol: Fix symbol parsing in certain cases: use the build-id as a symlink
  perf_counter/powerpc: Check oprofile_cpu_type for NULL before using it
  ftrace: Fix perf-tracepoint OOPS
  perf report: Add missing command line options to man page
  perf: Auto-detect libbfd
  perf report: Make --sort comm,dso,symbol the default
2009-08-07 10:43:07 -07:00
Eric Dumazet
9c8a8228d0 execve: must clear current->clear_child_tid
While looking at Jens Rosenboom bug report
(http://lkml.org/lkml/2009/7/27/35) about strange sys_futex call done from
a dying "ps" program, we found following problem.

clone() syscall has special support for TID of created threads.  This
support includes two features.

One (CLONE_CHILD_SETTID) is to set an integer into user memory with the
TID value.

One (CLONE_CHILD_CLEARTID) is to clear this same integer once the created
thread dies.

The integer location is a user provided pointer, provided at clone()
time.

kernel keeps this pointer value into current->clear_child_tid.

At execve() time, we should make sure kernel doesnt keep this user
provided pointer, as full user memory is replaced by a new one.

As glibc fork() actually uses clone() syscall with CLONE_CHILD_SETTID and
CLONE_CHILD_CLEARTID set, chances are high that we might corrupt user
memory in forked processes.

Following sequence could happen:

1) bash (or any program) starts a new process, by a fork() call that
   glibc maps to a clone( ...  CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID
   ...) syscall

2) When new process starts, its current->clear_child_tid is set to a
   location that has a meaning only in bash (or initial program) context
   (&THREAD_SELF->tid)

3) This new process does the execve() syscall to start a new program.
   current->clear_child_tid is left unchanged (a non NULL value)

4) If this new program creates some threads, and initial thread exits,
   kernel will attempt to clear the integer pointed by
   current->clear_child_tid from mm_release() :

        if (tsk->clear_child_tid
            && !(tsk->flags & PF_SIGNALED)
            && atomic_read(&mm->mm_users) > 1) {
                u32 __user * tidptr = tsk->clear_child_tid;
                tsk->clear_child_tid = NULL;

                /*
                 * We don't check the error code - if userspace has
                 * not set up a proper pointer then tough luck.
                 */
<< here >>      put_user(0, tidptr);
                sys_futex(tidptr, FUTEX_WAKE, 1, NULL, NULL, 0);
        }

5) OR : if new program is not multi-threaded, but spied by /proc/pid
   users (ps command for example), mm_users > 1, and the exiting program
   could corrupt 4 bytes in a persistent memory area (shm or memory mapped
   file)

If current->clear_child_tid points to a writeable portion of memory of the
new program, kernel happily and silently corrupts 4 bytes of memory, with
unexpected effects.

Fix is straightforward and should not break any sane program.

Reported-by: Jens Rosenboom <jens@mcbone.net>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sonny Rao <sonnyrao@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-07 10:39:56 -07:00
Xiao Guangrong
69dd647f96 generic-ipi: fix hotplug_cfd()
Use CONFIG_HOTPLUG_CPU, not CONFIG_CPU_HOTPLUG

When hot-unpluging a cpu, it will leak memory allocated at cpu hotplug,
but only if CPUMASK_OFFSTACK=y, which is default to n.

The bug was introduced by 8969a5ede0
("generic-ipi: remove kmalloc()").

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-07 10:39:55 -07:00
Eric Dumazet
bd3f02212d ring-buffer: Fix memleak in ring_buffer_free()
I noticed oprofile memleaked in linux-2.6 current tree,
and tracked this ring-buffer leak.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <4A7C06B9.2090302@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-07 12:46:39 -04:00
Li Zefan
9795447f71 lockdep: Fix file mode of lock_stat
/proc/lock_stat is writable.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A7BE7B6.10904@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-07 11:58:38 +02:00
Peter Zijlstra
1054598cab perf_counter: Fix double list iteration in per task precise stats
Brice Goglin reported this crash with per task precise stats:

> I finally managed to test the threaded perfcounter statistics (thanks a
> lot for implementing it). I am running 2.6.31-rc5 (with the AMD
> magny-cours patches but I don't think they matter here). I am trying to
> measure local/remote memory accesses per thread during the well-known
> stream benchmark. It's compiled with OpenMP using 16 threads on a
> quad-socket quad-core barcelona machine.
>
> Command line is:
>  /mnt/scratch/bgoglin/cpunode/linux-2.6.31/tools/perf/perf record -f -s
> -e r1000001e0 -e r1000002e0 -e r1000004e0 -e r1000008e0 ./stream
>
> It seems to work fine with a single -e <counter> on the command line
> while it crashes when there are at least 2 of them.
> It seems to work fine without -s as well.

A silly copy-paste resulted in a messed up iteration which would
cause the OOPS.

Reported-by: Brice Goglin <Brice.Goglin@inria.fr>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Brice Goglin <Brice.Goglin@inria.fr>
LKML-Reference: <1249574786.32113.550.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-06 20:25:18 +02:00
Robert Richter
469535a598 ring-buffer: Fix advance of reader in rb_buffer_peek()
When calling rb_buffer_peek() from ring_buffer_consume() and a
padding event is returned, the function rb_advance_reader() is
called twice. This may lead to missing samples or under high
workloads to the warning below. This patch fixes this. If a padding
event is returned by rb_buffer_peek() it will be consumed by the
calling function now.

Also, I simplified some code in ring_buffer_consume().

------------[ cut here ]------------
WARNING: at /dev/shm/.source/linux/kernel/trace/ring_buffer.c:2289 rb_advance_reader+0x2e/0xc5()
Hardware name: Anaheim
Modules linked in:
Pid: 29, comm: events/2 Tainted: G        W  2.6.31-rc3-oprofile-x86_64-standard-00059-g5050dc2 #1
Call Trace:
[<ffffffff8106776f>] ? rb_advance_reader+0x2e/0xc5
[<ffffffff81039ffe>] warn_slowpath_common+0x77/0x8f
[<ffffffff8103a025>] warn_slowpath_null+0xf/0x11
[<ffffffff8106776f>] rb_advance_reader+0x2e/0xc5
[<ffffffff81068bda>] ring_buffer_consume+0xa0/0xd2
[<ffffffff81326933>] op_cpu_buffer_read_entry+0x21/0x9e
[<ffffffff810be3af>] ? __find_get_block+0x4b/0x165
[<ffffffff8132749b>] sync_buffer+0xa5/0x401
[<ffffffff810be3af>] ? __find_get_block+0x4b/0x165
[<ffffffff81326c1b>] ? wq_sync_buffer+0x0/0x78
[<ffffffff81326c76>] wq_sync_buffer+0x5b/0x78
[<ffffffff8104aa30>] worker_thread+0x113/0x1ac
[<ffffffff8104dd95>] ? autoremove_wake_function+0x0/0x38
[<ffffffff8104a91d>] ? worker_thread+0x0/0x1ac
[<ffffffff8104dc9a>] kthread+0x88/0x92
[<ffffffff8100bdba>] child_rip+0xa/0x20
[<ffffffff8104dc12>] ? kthread+0x0/0x92
[<ffffffff8100bdb0>] ? child_rip+0x0/0x20
---[ end trace f561c0a58fcc89bd ]---

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: <stable@kernel.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-06 14:20:25 +02:00
Peter Zijlstra
af6af30c0f ftrace: Fix perf-tracepoint OOPS
Not all tracepoints are created equal, in specific the ftrace
tracepoints are created with TRACE_EVENT_FORMAT() which does
not generate the needed bits to tie them into perf counters.

For those events, don't create the 'id' file and fail
->profile_enable when their ID is specified through other
means.

Reported-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1249497664.5890.4.camel@laptop>
[ v2: fix build error in the !CONFIG_EVENT_PROFILE case ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-06 06:26:09 +02:00
Darren Hart
1bbf20835c rtmutex: Avoid deadlock in rt_mutex_start_proxy_lock()
In the event of a lock steal or owner died,
rt_mutex_start_proxy_lock() will give the rt_mutex to the
waiting task, but it fails to release the wait_lock. This leads
to subsequent deadlocks when other tasks try to acquire the
rt_mutex.

I also removed a few extra blank lines that really spaced this
routine out. I must have been high on the \n when I wrote this
originally...

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Dinakar Guniguntala <dino@in.ibm.com>
Cc: John Stultz <johnstul@linux.vnet.ibm.com>
LKML-Reference: <4A79D7F1.4000405@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-06 05:50:21 +02:00
Steven Rostedt
464e85eb0e ring-buffer: do not disable ring buffer on oops_in_progress
The commit:

  commit e0fdace10e
  Author: David Miller <davem@davemloft.net>
  Date:   Fri Aug 1 01:11:22 2008 -0700

    debug_locks: set oops_in_progress if we will log messages.

    Otherwise lock debugging messages on runqueue locks can deadlock the
    system due to the wakeups performed by printk().

    Signed-off-by: David S. Miller <davem@davemloft.net>
    Signed-off-by: Ingo Molnar <mingo@elte.hu>

Will permanently set oops_in_progress on any lockdep failure.
When this triggers it will cause any read from the ring buffer to
permanently disable the ring buffer (not to mention no locking of
printk).

This patch removes the check. It keeps the print in NMI which makes
sense. This is probably OK, since the ring buffer should not cause
something to set oops_in_progress anyway.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-05 20:20:00 -04:00
Steven Rostedt
0f2541d299 ring-buffer: fix check of try_to_discard result
The function ring_buffer_discard_commit inversed the code path
of the result of try_to_discard. It should skip incrementing the
entry counter if try_to_discard succeeded. But instead, it increments
the entry conder if it succeeded to discard, and does not increment
it if it fails.

The result of this bug is that filtering will make the stat counters
incorrect.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-05 20:19:59 -04:00
Linus Torvalds
a40694a38a Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_counter: Set the CONFIG_PERF_COUNTERS default to y if CONFIG_PROFILING=y
  perf: Fix read buffer overflow
  perf top: Add mwait_idle_with_hints to skip_symbols[]
  perf tools: Fix faulty check
  perf report: Update for the new FORK/EXIT events
  perf_counter: Full task tracing
  perf_counter: Collapse inherit on read()
  tracing, perf_counter: Add help text to CONFIG_EVENT_PROFILE
  perf_counter tools: Fix link errors with older toolchains
2009-08-04 15:32:40 -07:00
Linus Torvalds
ea5634246b 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 race in cpupri introduced by cpumask_var changes
  sched: Fix latencytop and sleep profiling vs group scheduling
2009-08-04 15:32:22 -07:00
Linus Torvalds
7193675dc8 Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  posix-timers: Fix oops in clock_nanosleep() with CLOCK_MONOTONIC_RAW
2009-08-04 15:32:08 -07:00
Linus Torvalds
9c66812b6b Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: Fix missing function_graph events when we splice_read from trace_pipe
  tracing: Fix invalid function_graph entry
  trace: stop tracer in oops_enter()
  ftrace: Only update $offset when we update $ref_func
  ftrace: Fix the conditional that updates $ref_func
  tracing: only truncate ftrace files when O_TRUNC is set
  tracing: show proper address for trace-printk format
2009-08-04 15:31:51 -07:00
Ingo Molnar
e16852cfc5 Merge branch 'tracing/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/urgent 2009-08-04 13:58:28 +02:00
Hiroshi Shimamoto
70d715fd05 posix-timers: Fix oops in clock_nanosleep() with CLOCK_MONOTONIC_RAW
Prevent calling do_nanosleep() with clockid
CLOCK_MONOTONIC_RAW, it may cause oops, such as NULL pointer
dereference.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: <stable@kernel.org>
LKML-Reference: <4A764FF3.50607@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-04 10:16:41 +02:00
Gregory Haskins
07903af152 sched: Fix race in cpupri introduced by cpumask_var changes
Background:

Several race conditions in the scheduler have cropped up
recently, which Steven and I have tracked down using ftrace.
The most recent one turns out to be a race in how the scheduler
determines a suitable migration target for RT tasks, introduced
recently with commit:

    commit 68e74568fb
    Date:   Tue Nov 25 02:35:13 2008 +1030

        sched: convert struct cpupri_vec cpumask_var_t.

The original design of cpupri allowed lockless readers to
quickly determine a best-estimate target.  Races between the
pri_active bitmap and the vec->mask were handled in the
original code because we would detect and return "0" when this
occured.  The design was predicated on the *effective*
atomicity (*) of caching the result of cpus_and() between the
cpus_allowed and the vec->mask.

Commit 68e74568 changed the behavior such that vec->mask is
accessed multiple times.  This introduces a subtle race, the
result of which means we can have a result that returns "1",
but with an empty bitmap.

*) yes, we know cpus_and() is not a locked operator across the
   entire composite array, but it is implicitly atomic on a
   per-word basis which is all the design required to work.

Implementation:

Rather than forgoing the lockless design, or reverting to a
stack-based cpumask_t, we simply check for when the race has
been encountered and continue processing in the event that the
race is hit.  This renders the removal race as if the priority
bit had been atomically cleared as well, and allows the
algorithm to execute correctly.

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090730145728.25226.92769.stgit@dev.haskins.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-02 14:23:29 +02:00
Peter Zijlstra
e414314cce sched: Fix latencytop and sleep profiling vs group scheduling
The latencytop and sleep accounting code assumes that any
scheduler entity represents a task, this is not so.

Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-02 14:10:12 +02:00
Peter Zijlstra
9f498cc5be perf_counter: Full task tracing
In order to be able to distinguish between no samples due to
inactivity and no samples due to task ended, Arjan asked for
PERF_EVENT_EXIT events. This is useful to the boot delay
instrumentation (bootchart) app.

This patch changes the PERF_EVENT_FORK to be emitted on every
clone, and adds PERF_EVENT_EXIT to be emitted on task exit,
after the task's counters have been closed.

This task tracing is controlled through: attr.comm || attr.mmap
and through the new attr.task field.

Suggested-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
[ cleaned up perf_counter.h a bit ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-02 13:47:56 +02:00
Peter Zijlstra
e53c099470 perf_counter: Collapse inherit on read()
Currently the counter value returned by read() is the value of
the parent counter, to which child counters are only fed back
on child exit.

Thus read() can return rather erratic (and meaningless) numbers
depending on the state of the child processes.

Change this by always iterating the full child hierarchy on
read() and sum all counters.

Suggested-by: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-02 13:47:54 +02:00
Linus Torvalds
0dd8486b5c do_sigaltstack: small cleanups
The previous commit ("do_sigaltstack: avoid copying 'stack_t' as a
structure to user space") fixed a real bug.  This one just cleans up the
copy from user space to that gcc can generate better code for it (and so
that it looks the same as the later copy back to user space).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-01 11:18:56 -07:00
Linus Torvalds
0083fc2c50 do_sigaltstack: avoid copying 'stack_t' as a structure to user space
Ulrich Drepper correctly points out that there is generally padding in
the structure on 64-bit hosts, and that copying the structure from
kernel to user space can leak information from the kernel stack in those
padding bytes.

Avoid the whole issue by just copying the three members one by one
instead, which also means that the function also can avoid the need for
a stack frame.  This also happens to match how we copy the new structure
from user space, so it all even makes sense.

[ The obvious solution of adding a memset() generates horrid code, gcc
  does really stupid things. ]

Reported-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-01 10:46:52 -07:00
Linus Torvalds
b592972493 Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing/stat: Fix seqfile memory leak
  function-graph: Fix seqfile memory leak
  trace_stack: Fix seqfile memory leak
  profile: Suppress warning about large allocations when profile=1 is specified
2009-07-30 16:46:58 -07:00
Masami Hiramatsu
ec30c5f3a1 kprobes: Use kernel_text_address() for checking probe address
Use kernel_text_address() for checking probe address instead of
__kernel_text_address(), because __kernel_text_address() returns true
for init functions even after relaseing those functions.

That will hit a BUG() in text_poke().

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-30 16:44:06 -07:00
Mel Gorman
b62f495dad profile: suppress warning about large allocations when profile=1 is specified
When profile= is used, a large buffer is allocated early at boot.  This
can be larger than what the page allocator can provide so it prints a
warning.  However, the caller is able to handle the situation so this
patch suppresses the warning.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-29 19:10:36 -07:00
KAMEZAWA Hiroyuki
887032670d cgroup avoid permanent sleep at rmdir
After commit ec64f51545 ("cgroup: fix
frequent -EBUSY at rmdir"), cgroup's rmdir (especially against memcg)
doesn't return -EBUSY by temporary ref counts.  That commit expects all
refs after pre_destroy() is temporary but...it wasn't.  Then, rmdir can
wait permanently.  This patch tries to fix that and change followings.

 - set CGRP_WAIT_ON_RMDIR flag before pre_destroy().
 - clear CGRP_WAIT_ON_RMDIR flag when the subsys finds racy case.
   if there are sleeping ones, wakes them up.
 - rmdir() sleeps only when CGRP_WAIT_ON_RMDIR flag is set.

Tested-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Reported-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Reviewed-by: Paul Menage <menage@google.com>
Acked-by: Balbir Sigh <balbir@linux.vnet.ibm.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-29 19:10:35 -07:00
Li Zefan
096b7fe012 cgroups: fix pid namespace bug
The bug was introduced by commit cc31edceee
("cgroups: convert tasks file to use a seq_file with shared pid array").

We cache a pid array for all threads that are opening the same "tasks"
file, but the pids in the array are always from the namespace of the
last process that opened the file, so all other threads will read pids
from that namespace instead of their own namespaces.

To fix it, we maintain a list of pid arrays, which is keyed by pid_ns.
The list will be of length 1 at most time.

Reported-by: Paul Menage <menage@google.com>
Idea-by: Paul Menage <menage@google.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Reviewed-by: Serge Hallyn <serue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-29 19:10:35 -07:00
Hidetoshi Seto
11c7da4b0c kexec: fix omitting offset in extended crashkernel syntax
Setting
 "crashkernel=512M-2G:64M,2G-:128M"
does not work but it turns to work if it has a trailing-whitespace,
like
 "crashkernel=512M-2G:64M,2G-:128M ".

It was because of a bug in the parser, running over the cmdline.

This patch adds a check of the termination.

Reported-by: Jin Dongming <jin.dongming@np.css.fujitsu.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Tested-by: Jin Dongming <jin.dongming@np.css.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-29 19:10:34 -07:00
Rik van Riel
933b787b57 mm: copy over oom_adj value at fork time
Fix a post-2.6.31 regression which was introduced by
2ff05b2b4e ("oom: move oom_adj value from
task_struct to mm_struct").

After moving the oom_adj value from the task struct to the mm_struct, the
oom_adj value was no longer properly inherited by child processes.

Copying over the oom_adj value at fork time fixes that bug.

[kosaki.motohiro@jp.fujitsu.com: test for current->mm before dereferencing it]
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Paul Menage <manage@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-29 19:10:34 -07:00
Lai Jiangshan
74e7ff8c50 tracing: Fix missing function_graph events when we splice_read from trace_pipe
About a half events are missing when we splice_read
from trace_pipe. They are unexpectedly consumed because we ignore
the TRACE_TYPE_NO_CONSUME return value used by the function graph
tracer when it needs to consume the events by itself to walk on
the ring buffer.

The same problem appears with ftrace_dump()

Example of an output before this patch:

1)               |      ktime_get_real() {
1)   2.846 us    |          read_hpet();
1)   4.558 us    |        }
1)   6.195 us    |      }

After this patch:

0)               |      ktime_get_real() {
0)               |        getnstimeofday() {
0)   1.960 us    |          read_hpet();
0)   3.597 us    |        }
0)   5.196 us    |      }

The fix also applies on 2.6.30

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: stable@kernel.org
LKML-Reference: <4A6EEC52.90704@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-07-28 23:17:23 +02:00
Lai Jiangshan
38ceb592fc tracing: Fix invalid function_graph entry
When print_graph_entry() computes a function call entry event, it needs
to also check the next entry to guess if it matches the return event of
the current function entry.
In order to look at this next event, it needs to consume the current
entry before going ahead in the ring buffer.

However, if the current event that gets consumed is the last one in the
ring buffer head page, the ring_buffer may reuse the page for writers.
The consumed entry will then become invalid because of possible
racy overwriting.

Me must then handle this entry by making a copy of it.

The fix also applies on 2.6.30

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: stable@kernel.org
LKML-Reference: <4A6EEAEC.3050508@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-07-28 23:17:23 +02:00
Oleg Nesterov
9ae260270c update the comment in kthread_stop()
Commit 63706172f3 ("kthreads: rework
kthread_stop()") removed the limitation that the thread function mysr
not call do_exit() itself, but forgot to update the comment.

Since that commit it is OK to use kthread_stop() even if kthread can
exit itself.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-27 12:15:46 -07:00
Mike Frysinger
6560dc160f module: use MODULE_SYMBOL_PREFIX with module_layout
The check_modstruct_version() needs to look up the symbol "module_layout"
in the kernel, but it does so literally and not by a C identifier.  The
trouble is that it does not include a symbol prefix for those ports that
need it (like the Blackfin and H8300 port).  So make sure we tack on the
MODULE_SYMBOL_PREFIX define to the front of it.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-27 12:15:45 -07:00
Thomas Gleixner
bdff78707f trace: stop tracer in oops_enter()
If trace_printk_on_oops is set we lose interesting trace information
when the tracer is enabled across oops handling and printing. We want
the trace which might give us information _WHY_ we oopsed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-07-24 15:30:45 -04:00
Steven Rostedt
8650ae32ef tracing: only truncate ftrace files when O_TRUNC is set
The current code will truncate the ftrace files contents if O_APPEND
is not set and the file is opened in write mode. This is incorrect.
It should only truncate the file if O_TRUNC is set. Otherwise
if one of these files is opened by a C program with fopen "r+",
it will incorrectly truncate the file.

Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-07-23 10:07:18 -04:00