Ingo Molnar [Sat, 30 May 2009 10:38:51 +0000 (12:38 +0200)]
perf_counter tools: Fix 'make install'
'make install' didnt install perf itself - which needs a special
rule to be copied to bindir.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Sat, 30 May 2009 10:38:51 +0000 (12:38 +0200)]
perf_counter tools: Print 'CPU utilization factor' in builtin-stat
Before:
Performance counter stats for '/home/mingo/hackbench':
5728.862689 task clock ticks (msecs)
34426 context switches # 0.006 M/sec
3835 CPU migrations # 0.001 M/sec
18158 pagefaults # 0.003 M/sec
16218109156 CPU cycles # 2830.947 M/sec
13519616840 instructions # 2359.913 M/sec
55941661 cache references # 9.765 M/sec
23554938 cache misses # 4.112 M/sec
Wall-clock time elapsed: 528.886980 msecs
After:
Performance counter stats for '/home/mingo/hackbench':
5845.443541 task clock ticks # 11.886 CPU utilization factor
38289 context switches # 0.007 M/sec
4208 CPU migrations # 0.001 M/sec
17755 pagefaults # 0.003 M/sec
16664668576 CPU cycles # 2850.882 M/sec
13468113991 instructions # 2304.036 M/sec
57445468 cache references # 9.827 M/sec
26896502 cache misses # 4.601 M/sec
Wall-clock time elapsed: 491.802357 msecs
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Fri, 29 May 2009 20:03:07 +0000 (17:03 -0300)]
perf_counter tools: Add locking to perf top
perf_counter tools: Add locking to perf top
We need to protect the active_symbols list as two threads change it:
the main thread adding entries to the head and the display thread
decaying entries from any place in the list.
Also related: take a snapshot of syme->count[0] before using it to
calculate the weight and to show the same number used in this calc when
displaying the symbol usage.
Reported-by: Mike Galbraith <efault@gmx.de>
Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <
20090529200307.GR4747@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Fri, 29 May 2009 16:48:59 +0000 (13:48 -0300)]
perf_counter tools: Shorten the DSO names using cwd
[acme@emilia linux-2.6-tip]$ pwd
/home/acme/git/linux-2.6-tip
Before (still available using -P/--full-paths)
[acme@emilia linux-2.6-tip]$ perf report -P | head -10
11.48% perf: 7454 [kernel]: clear_page_c
4.89% perf: 7454 [kernel]: vsnprintf
4.61% perf: 7454 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__find_symbol
4.09% perf: 7454 [kernel]: number
4.06% perf: 7454 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__fprintf
4.00% perf: 7454 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: symbol_filter
New default:
[acme@emilia linux-2.6-tip]$ perf report | head -10
11.48% perf: 7454 [kernel]: clear_page_c
4.89% perf: 7454 [kernel]: vsnprintf
4.61% perf: 7454 ./Documentation/perf_counter/perf: dso__find_symbol
4.09% perf: 7454 [kernel]: number
4.06% perf: 7454 ./Documentation/perf_counter/perf: dso__fprintf
4.00% perf: 7454 ./Documentation/perf_counter/perf: symbol_filter
Suggested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <
20090529164859.GN4747@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Fri, 29 May 2009 12:25:58 +0000 (14:25 +0200)]
perf_counter: Ammend cleanup in fork() fail
When fork() fails we cannot use perf_counter_exit_task() since that
assumes to operate on current. Write a new helper that cleans up
unused/clean contexts.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Fri, 29 May 2009 12:51:57 +0000 (14:51 +0200)]
perf_counter: Clean up task_ctx vs interrupts
Remove the local_irq_save() etc.. in routines that are smp function
calls, or have IRQs disabled by other means.
Then change the COMM, MMAP, and swcounter context iteration to
current->perf_counter_ctxp and RCU, since it really doesn't matter
which context they iterate, they're all folded.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Fri, 29 May 2009 12:25:58 +0000 (14:25 +0200)]
perf_counter: Fix COMM and MMAP events for cpu wide counters
Commit
a63eaf34ae6 ("perf_counter: Dynamically allocate tasks'
perf_counter_context struct") broke COMM and MMAP notification for
cpu wide counters by dropping out early if there was no task context,
thereby also not iterating the cpu context.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Sun, 17 May 2009 09:08:41 +0000 (11:08 +0200)]
perf_counter: Robustify counter-free logic
This fixes a nasty crash and highlights a bug that we were
freeing failed-fork() counters incorrectly.
(the fix for that will come separately)
[ Impact: fix crashes/lockups with inherited counters ]
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Fri, 29 May 2009 09:25:09 +0000 (11:25 +0200)]
perf_counter: Fix cpuctx->task_ctx races
Peter noticed that we are sometimes reading cpuctx->task_ctx with
interrupts enabled.
Noticed-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Fri, 29 May 2009 06:06:20 +0000 (16:06 +1000)]
perf_counter: Don't swap contexts containing locked mutex
Peter Zijlstra pointed out that under some circumstances, we can take
the mutex in a context or a counter and then swap that context or
counter to another task, potentially leading to lock order inversions
or the mutexes not protecting what they are supposed to protect.
This fixes the problem by making sure that we never take a mutex in a
context or counter which could get swapped to another task. Most of
the cases where we take a mutex is on a top-level counter or context,
i.e. a counter which has an fd associated with it or a context that
contains such a counter. This adds WARN_ON_ONCE statements to verify
that.
The two cases where we need to take the mutex on a context that is a
clone of another are in perf_counter_exit_task and
perf_counter_init_task. The perf_counter_exit_task case is solved by
uncloning the context before starting to remove the counters from it.
The perf_counter_init_task is a little trickier; we temporarily
disable context swapping for the parent (forking) task by setting its
ctx->parent_gen to the all-1s value after locking the context, if it
is a cloned context, and restore the ctx->parent_gen value at the end
if the context didn't get uncloned in the meantime.
This also moves the increment of the context generation count to be
within the same critical section, protected by the context mutex, that
adds the new counter to the context. That way, taking the mutex is
sufficient to ensure that both the counter list and the generation
count are stable.
[ Impact: fix hangs, races with inherited and PID counters ]
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <18975.31580.520676.619896@drongo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Fri, 29 May 2009 07:10:54 +0000 (09:10 +0200)]
perf_counter tools: Also display time-normalized stat results
Add new column that normalizes counter results by
'nanoseconds spent running' unit.
Before:
Performance counter stats for '/home/mingo/hackbench':
10469.403605 task clock ticks (msecs)
75502 context switches (events)
9501 CPU migrations (events)
36158 pagefaults (events)
31975676185 CPU cycles (events)
26257738659 instructions (events)
108740581 cache references (events)
54606088 cache misses (events)
Wall-clock time elapsed: 810.514504 msecs
After:
Performance counter stats for '/home/mingo/hackbench':
10469.403605 task clock ticks (msecs)
75502 context switches # 0.007 M/sec
9501 CPU migrations # 0.001 M/sec
36158 pagefaults # 0.003 M/sec
31975676185 CPU cycles # 3054.202 M/sec
26257738659 instructions # 2508.045 M/sec
108740581 cache references # 10.387 M/sec
54606088 cache misses # 5.216 M/sec
Wall-clock time elapsed: 810.514504 msecs
The advantage of that column is that it is characteristic of the
execution workflow, regardless of runtime. Hence 'hackbench 10'
will look similar to 'hackbench 15' - while the absolute counter
values are very different.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Fri, 29 May 2009 07:10:54 +0000 (09:10 +0200)]
perf_counter tools: Split display into reading and printing
We introduce the extra pass to allow the print-out to possibly
rely on already read counters.
[ Impact: cleanup ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Fri, 29 May 2009 07:10:54 +0000 (09:10 +0200)]
perf_counter tools: Clean up builtin-stat.c's do_perfstat()
[ Impact: cleanup ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Yong Wang [Fri, 29 May 2009 05:28:35 +0000 (13:28 +0800)]
perf_counter/x86: Always use NMI for performance-monitoring interrupt
Always use NMI for performance-monitoring interrupt as there could be
racy situations if we switch between irq and nmi mode frequently.
Signed-off-by: Yong Wang <yong.y.wang@intel.com>
LKML-Reference: <
20090529052835.GA13657@ywang-moblin2.bj.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mike Galbraith [Fri, 29 May 2009 06:23:16 +0000 (08:23 +0200)]
perf_counter tools: Fix top symbol table max_ip typo
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mike Galbraith [Fri, 29 May 2009 04:46:46 +0000 (06:46 +0200)]
perf_counter tools: Fix top symbol table dump typo
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mike Galbraith [Thu, 28 May 2009 14:25:34 +0000 (16:25 +0200)]
perf_counter tools: Document '--' option parsing terminator
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Thu, 28 May 2009 17:55:41 +0000 (14:55 -0300)]
perf_counter tools: Convert builtin-top to use libperf symbol routines
Now both perf top and report use the same routines.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <
20090528175541.GG4747@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Thu, 28 May 2009 17:55:26 +0000 (14:55 -0300)]
perf_counter tools: Optionally pass a symbol filter to the dso load routines
Will be used by perf top.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <
20090528175526.GF4747@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Thu, 28 May 2009 17:55:19 +0000 (14:55 -0300)]
perf_counter tools: Consolidate dso methods to load kernel symbols
Now one has just to use dso__load_kernel() optionally passing a vmlinux
filename.
Will make things easier for perf top that will want to pass a callback
to filter some symbols.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Thu, 28 May 2009 17:55:13 +0000 (14:55 -0300)]
perf_counter tools: struct symbol priv area
When creating a dso instance allow asking that all symbols in this dso
have a private area just before the symbol.
perf top will use this for its counters, etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <
20090528175513.GD4747@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Thu, 28 May 2009 17:55:04 +0000 (14:55 -0300)]
perf_counter tools: Move symbol resolution classes from report to libperf
Will be used by perf top as well.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <
20090528175504.GC4747@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Thu, 28 May 2009 12:18:17 +0000 (22:18 +1000)]
perf_counter: Fix race in attaching counters to tasks and exiting
Commit
564c2b21 ("perf_counter: Optimize context switch between
identical inherited contexts") introduced a race where it is possible
that a counter being attached to a task could get attached to the
wrong task, if the task is one that has inherited its context from
another task via fork. This happens because the optimized context
switch could switch the context to another task after find_get_context
has read task->perf_counter_ctxp. In fact, it's possible that the
context could then get freed, if the other task then exits.
This fixes the problem by protecting both the context switch and the
critical code in find_get_context with spinlocks. The context switch
locks the cxt->lock of both the outgoing and incoming contexts before
swapping them. That means that once code such as find_get_context
has obtained the spinlock for the context associated with a task,
the context can't get swapped to another task. However, the context
may have been swapped in the interval between reading
task->perf_counter_ctxp and getting the lock, so it is necessary to
check and retry.
To make sure that none of the contexts being looked at in
find_get_context can get freed, this changes the context freeing code
to use RCU. Thus an rcu_read_lock() is sufficient to ensure that no
contexts can get freed. This part of the patch is lifted from a patch
posted by Peter Zijlstra.
This also adds a check to make sure that we can't add a counter to a
task that is exiting.
There is also a race between perf_counter_exit_task and
find_get_context; this solves the race by moving the get_ctx that
was in perf_counter_alloc into the locked region in find_get_context,
so that once find_get_context has got the context for a task, it
won't get freed even if the task calls perf_counter_exit_task. It
doesn't matter if new top-level (non-inherited) counters get attached
to the context after perf_counter_exit_task has detached the context
from the task. They will just stay there and never get scheduled in
until the counters' fds get closed, and then perf_release will remove
them from the context and eventually free the context.
With this, we are now doing the unclone in find_get_context rather
than when a counter was added to or removed from a context (actually,
we were missing the unclone_ctx() call when adding a counter to a
context). We don't need to unclone when removing a counter from a
context because we have no way to remove a counter from a cloned
context.
This also takes out the smp_wmb() in find_get_context, which Peter
Zijlstra pointed out was unnecessary because the cmpxchg implies a
full barrier anyway.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <18974.33033.667187.273886@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Thu, 28 May 2009 08:52:00 +0000 (10:52 +0200)]
perf_counter tools: report: Add help text for --sort
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Thu, 28 May 2009 09:08:33 +0000 (11:08 +0200)]
perf_counter tools: report: Implement header output for --sort variants
Implement this style of header:
#
# Overhead Command File: Symbol
# ........ ....... ............
#
for the various --sort variants as well.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Thu, 28 May 2009 09:41:50 +0000 (11:41 +0200)]
perf_counter: Fix perf_counter_init_task() on !CONFIG_PERF_COUNTERS
Pointed out by compiler warnings:
tip/include/linux/perf_counter.h:644: warning: no return statement in function returning non-void
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Wed, 27 May 2009 20:13:17 +0000 (22:13 +0200)]
pref_counter: tools: report: Robustify in case of weird events
This error condition:
aldebaran:~/linux/linux/Documentation/perf_counter> perf report
dso__load_sym: cannot get elf header.
failed to open: /etc/ld.so.cache
problem processing PERF_EVENT_MMAP, bailing out
caused the profile to be very short - as the error was at the beginning
of the file and we bailed out completely.
Be more permissive and consider the event broken instead.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Wed, 27 May 2009 19:36:22 +0000 (21:36 +0200)]
pref_counter: tools: report: Add header printout & prettify
Old default output:
3.12% perf-report [.] ./perf-report: dsos__find
2.44% perf-report [k] kernel: kallsyms_expand_symbol
2.28% :4483 [.] <unknown>: <unknown>
2.05% :4174 [k] kernel: _spin_lock_irqsave
2.01% perf-report [k] kernel: vsnprintf
1.92% perf-report [k] kernel: format_decode
1.92% :4438 [k] kernel: _spin_lock
New default output:
#
# Overhead Command File: Symbol
# ........ ....... ............
#
6.54% perf [k] kernel: kallsyms_expand_symbol
6.26% perf [.] /home/mingo/tip/Documentation/perf_counter/perf: dso__insert_symbol
4.76% perf [.] /home/mingo/tip/Documentation/perf_counter/perf: hex2long
4.55% perf [k] kernel: number
4.48% perf [k] kernel: format_decode
4.09% perf [k] kernel: vsnprintf
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <
20090527182101.
229504802@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Wed, 27 May 2009 18:20:28 +0000 (20:20 +0200)]
pref_counter: tools: report: Add dso sorting
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <
20090527182101.
229504802@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Wed, 27 May 2009 18:20:27 +0000 (20:20 +0200)]
perf_counter: tools: report: Add comm sorting
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <
20090527182101.
129302022@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Wed, 27 May 2009 18:20:26 +0000 (20:20 +0200)]
pref_counter: tools: report: Add --sort option
option parsing for dynamic sorting.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <
20090527182101.
041817692@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Wed, 27 May 2009 18:20:25 +0000 (20:20 +0200)]
perf_counter: tools: report: Dynamic sort/print bits
Make the sorting and printing dynamic.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <
20090527182100.
921953817@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Wed, 27 May 2009 18:20:24 +0000 (20:20 +0200)]
perf_counter: tools: report: Rework histogram code
In preparation for configurable sorting, rework the histgram code a bit.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <
20090527182100.
796410098@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Wed, 27 May 2009 18:20:23 +0000 (20:20 +0200)]
perf_counter: tools: report: Add vmlinux support
Allow to use vmlinux instead of kallsyms.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <
20090527182100.
740018486@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Wed, 27 May 2009 11:35:35 +0000 (13:35 +0200)]
perf_counter: tools: /usr/lib/debug%s.debug support
Some distros seem to store debuginfo in weird places.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Wed, 27 May 2009 11:19:59 +0000 (13:19 +0200)]
perf report: Remove <ctype.h> include
Pekka reported build failure in builtin-report.c:
CC builtin-report.o
In file included from builtin-report.c:7:
/usr/include/ctype.h:102: error: expected expression before token
And observed:
| Removing #include <ctype.h> from builtin-report.c makes the problem
| go away. I am running Ubuntu 9.04 that has gcc 4.3.3 and libc 2.9.
Reported-by: Pekka J Enberg <penberg@cs.helsinki.fi>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mike Galbraith [Wed, 27 May 2009 08:10:51 +0000 (10:10 +0200)]
perf record: Fix the profiling of existing pid or whole box
Perf record bails if no command argument is provided, so you can't use
naked -a or -p to profile a running task or the whole box.
Allow foreground profiling of an existing pid or the entire system.
[ Impact: fix command option handling bug ]
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Wed, 27 May 2009 07:50:13 +0000 (09:50 +0200)]
perf_counter tools: Add built-in pager support
Add Git's pager.c (and sigchain) code. A command only
has to call setup_pager() to get paged interactive
output.
Non-interactive (redirected, command-piped, etc.) uses
are not affected.
Update perf-report to make use of this.
[ Impact: new feature ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Wed, 27 May 2009 07:33:18 +0000 (09:33 +0200)]
perf_counter tools: Rename output.perf to perf.data
output.perf is only output to perf-record - it's input to
perf-report. So change it to a more direction-neutral name.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Wed, 27 May 2009 07:10:38 +0000 (09:10 +0200)]
perf_counter tools: Introduce stricter C code checking
Tighten up our C code requirements:
- disallow warnings
- disallow declarations-mixed-with-statements
- require proper prototypes
- require C99 (with gcc extensions)
Fix up a ton of problems these measures unearth:
- unused functions
- needlessly global functions
- missing prototypes
- code mixed with declarations
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <
20090526222155.GJ4424@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Tue, 26 May 2009 22:46:14 +0000 (19:46 -0300)]
perf report: Show the IP only in --verbose mode
perf: report should show the IP only in --verbose mode
[acme@emilia ~]$ perf report | head
4.95 find [k] _spin_lock
2.19 find [k] ext3fs_dirhash [ext3]
1.87 find [k] __rcu_read_lock
1.86 find [k] _atomic_dec_and_lock
1.86 find [.] /lib64/libc-2.5.so: __GI_strlen
1.85 find [k] __kmalloc
1.62 find [.] /lib64/libc-2.5.so: vfprintf
1.59 find [k] __rcu_read_unlock
1.55 find [k] __d_lookup
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <
20090526224614.GK4424@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Wed, 27 May 2009 06:38:48 +0000 (08:38 +0200)]
perf report: Only load text symbols from kallsyms, fix
- allow 'W' symbols too
- Convert initializations to C99 style
- whitespace cleanups
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <
20090526222155.GJ4424@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Tue, 26 May 2009 22:21:55 +0000 (19:21 -0300)]
perf report: Only load text symbols from kallsyms
Just like we do for userspace when reading the symtab, reducing the
number of entries we insert on the symbols rbtree.
Before:
[acme@emilia ~]$ rm -f perf_report.perf ; perf record -o perf_report.perf perf stat perf report > /dev/null
Performance counter stats for 'perf':
218.138382 task clock ticks (msecs)
4 context switches (events)
8 CPU migrations (events)
2136 pagefaults (events)
32746212 CPU cycles (events) (scaled from 67.04%)
11961102 instructions (events) (scaled from 66.19%)
49841 cache references (events) (scaled from 21.96%)
13777 cache misses (events) (scaled from 21.98%)
Wall-clock time elapsed: 218.702477 msecs
[acme@emilia ~]$ perf report -i perf_report.perf | head
11.06 perf [.] 0x00000000000057cb /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__find_symbol
9.15 perf [.] 0x00000000000056a0 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__insert_symbol
8.72 perf [k] 0xffffffff8101b1d2 intel_pmu_enable_all
8.51 perf [.] 0x0000000000006672 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: thread__symbol_incnew
3.83 perf [k] 0xffffffff811cfc5a vsnprintf
3.40 perf [.] 0x0000000000005e33 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex
3.40 perf [.] 0x0000000000005ec7 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex2long
3.19 perf [k] 0xffffffff811ce1c1 number
2.77 perf [.] 0x0000000000006869 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: threads__findnew
2.77 perf [.] 0x000000000000fde3 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: rb_insert_color
[acme@emilia ~]$
After:
acme@emilia ~]$ rm -f perf_report.perf ; perf record -o perf_report.perf perf stat perf report > /dev/null
Performance counter stats for 'perf':
190.228511 task clock ticks (msecs)
4 context switches (events)
7 CPU migrations (events)
1625 pagefaults (events)
29578745 CPU cycles (events) (scaled from 66.92%)
10516914 instructions (events) (scaled from 66.47%)
44015 cache references (events) (scaled from 22.04%)
8248 cache misses (events) (scaled from 22.07%)
Wall-clock time elapsed: 190.816096 msecs
[acme@emilia ~]$ perf report -i perf_report.perf | head
15.99 perf [.] 0x00000000000057a9 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__find_symbol
10.87 perf [.] 0x000000000000674d /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: thread__symbol_incnew
8.74 perf [k] 0xffffffff8101b1d2 intel_pmu_enable_all
5.54 perf [.] 0x0000000000005e42 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex
4.48 perf [.] 0x0000000000005ebe /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex2long
4.48 perf [k] 0xffffffff811cfba0 vsnprintf
3.84 perf [.] 0x00000000000056b4 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__insert_symbol
3.62 perf [.] 0x00000000000068d0 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: threads__findnew
3.20 perf [k] 0xffffffff811ce0b3 number
2.56 perf [.] 0x0000000000006d78 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: __cmd_report
[acme@emilia ~]$
[ Impact: optimization ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <
20090526222155.GJ4424@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Tue, 26 May 2009 22:20:57 +0000 (19:20 -0300)]
perf report: Use hex2long instead of sscanf
Before:
[acme@emilia ~]$ perf record -o perf_report.perf perf stat perf report > /dev/null
Performance counter stats for 'perf':
245.414985 task clock ticks (msecs)
6 context switches (events)
6 CPU migrations (events)
2108 pagefaults (events)
37493013 CPU cycles (events) (scaled from 67.04%)
13576789 instructions (events) (scaled from 66.76%)
57931 cache references (events) (scaled from 21.96%)
12263 cache misses (events) (scaled from 21.98%)
Wall-clock time elapsed: 246.575587 msecs
[acme@emilia ~]$ perf report -i perf_report.perf | head
12.15 perf [.] 0x000000000005432a /lib64/libc-2.5.so: _IO_vfscanf_internal
9.38 perf [k] 0xffffffff8101b1d2 intel_pmu_enable_all
8.53 perf [.] 0x00000000000056b8 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__insert_symbol
6.61 perf [.] 0x00000000000057cb /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__find_symbol
5.33 perf [k] 0xffffffff811ce082 number
4.69 perf [.] 0x0000000000034829 /lib64/libc-2.5.so: ____strtoull_l_internal
4.48 perf [.] 0x0000000000006505 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: thread__symbol_incnew
3.41 perf [.] 0x000000000000fce6 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: rb_insert_color
3.20 perf [k] 0xffffffff811cfc01 vsnprintf
2.99 perf [k] 0xffffffff811ce5e8 format_decode
After:
[acme@emilia ~]$ perf record -o perf_report.perf perf stat perf report > /dev/null
Performance counter stats for 'perf':
218.186805 task clock ticks (msecs)
4 context switches (events)
7 CPU migrations (events)
2133 pagefaults (events)
32735365 CPU cycles (events) (scaled from 67.04%)
11952309 instructions (events) (scaled from 66.26%)
50314 cache references (events) (scaled from 21.96%)
13228 cache misses (events) (scaled from 21.98%)
Wall-clock time elapsed: 218.810451 msecs
[acme@emilia ~]$ perf report -i perf_report.perf | head
10.68 perf [.] 0x000000000000578d /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__find_symbol
9.62 perf [.] 0x00000000000065f7 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: thread__symbol_incnew
9.40 perf [.] 0x00000000000056b4 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__insert_symbol
9.19 perf [k] 0xffffffff8101b1d2 intel_pmu_enable_all
5.13 perf [.] 0x0000000000005ec7 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex2long
4.49 perf [k] 0xffffffff81083808 kallsyms_expand_symbol
3.85 perf [k] 0xffffffff811ce2c1 number
3.63 perf [.] 0x0000000000005e81 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex
2.99 perf [.] 0x000000000000fd5b /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: rb_insert_color
2.99 perf [k] 0xffffffff811cf251 string
[acme@emilia ~]$
[ Impact: optimization ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <
20090526222057.GI4424@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Tue, 26 May 2009 19:19:04 +0000 (16:19 -0300)]
perf report: Sort output by symbol usage
[acme@emilia ~]$ perf record find / > /dev/null 2>&1
[acme@emilia ~]$ perf stat perf report | head -20
4.95 find [k] 0xffffffff81393d65 _spin_lock
3.89 find [.] 0x000000000000af89 /usr/bin/find: <unknown>
2.19 find [k] 0xffffffffa00518e0 ext3fs_dirhash
1.87 find [k] 0xffffffff810a6cea __rcu_read_lock
1.86 find [k] 0xffffffff811c7312 _atomic_dec_and_lock
1.86 find [.] 0x00000000000782ab /lib64/libc-2.5.so: __GI_strlen
1.85 find [k] 0xffffffff810fedfb __kmalloc
1.62 find [.] 0x00000000000430ff /lib64/libc-2.5.so: vfprintf
1.59 find [k] 0xffffffff810a6d6d __rcu_read_unlock
1.55 find [k] 0xffffffff81119395 __d_lookup
1.39 find [.] 0x0000000000071b40 /lib64/libc-2.5.so: _int_malloc
1.30 find [k] 0xffffffffa031c4fc nfs_do_filldir
1.21 find [k] 0xffffffff811876a5 avc_has_perm_noaudit
1.15 find [k] 0xffffffff810fef62 kmem_cache_alloc
1.07 find [k] 0xffffffff811d03fb copy_user_generic_string
1.03 find [k] 0xffffffffa0043882 ext3_htree_store_dirent
0.99 find [k] 0xffffffff81393ebb _spin_lock_bh
0.98 find [k] 0xffffffffa03319a2 nfs3_decode_dirent
0.97 find [k] 0xffffffff8100bf20 system_call
0.92 find [k] 0xffffffff8139437e _spin_unlock
Performance counter stats for 'perf':
244.278972 task clock ticks (msecs)
8 context switches (events)
9 CPU migrations (events)
2104 pagefaults (events)
35329669 CPU cycles (events) (scaled from 75.40%)
13740366 instructions (events) (scaled from 75.49%)
59073 cache references (events) (scaled from 24.60%)
196 cache misses (events) (scaled from 24.51%)
Wall-clock time elapsed: 246.060717 msecs
[acme@emilia ~]$
[acme@emilia ~]$ grep "model name" /proc/cpuinfo | head -1
model name : Intel(R) Xeon(R) CPU E5405 @ 2.00GHz
[acme@emilia ~]$ grep "model name" /proc/cpuinfo | wc -l
8
[acme@emilia ~]$
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <
20090526191904.GH4424@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Tue, 26 May 2009 18:51:47 +0000 (20:51 +0200)]
perf report: More robust error handling
Don't let funny events confuse us, stick to what we know and
try to find sensible data again.
If we find an unknown event, check we're still u64 aligned, and
increment by one u64. This ensures we're bound to happen upon a
valid event soon.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 17:03:36 +0000 (19:03 +0200)]
perf report: add more debugging
Add the offset of the file we are analyzing, and the size of the record.
In case of problems it's easier to see where the parser lost track.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 16:53:17 +0000 (18:53 +0200)]
perf report: add counter for unknown events
Add a counter for unknown event records.
[ Impact: improve debugging ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 16:48:58 +0000 (18:48 +0200)]
perf report: add --dump-raw-trace option
To help the inspection of various data files, implement an ASCII dump
method that just dumps the records as they are read in - then we exit.
[ Impact: new feature ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Tue, 26 May 2009 15:21:34 +0000 (12:21 -0300)]
perf: Don't assume /proc/kallsyms is ordered
perf: Don't assume /proc/kallsyms is ordered
Since we _are_ ordering it by the symbol start, just traverse the
freshly built rbtree setting the prev->end members to curr->start - 1.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090526152134.GF4424@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Tue, 26 May 2009 14:14:27 +0000 (11:14 -0300)]
perf report: Fix kernel symbol resolution
kallsyms have just the symbol start, so we need to read two lines
to get the len.
[ Impact: fix incorrect kernel symbol display in perf report ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Tue, 26 May 2009 13:30:22 +0000 (15:30 +0200)]
perf report: Fix ELF symbol parsing
[ Impact: fix DSO symbol output in perf report ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mike Galbraith [Tue, 26 May 2009 13:25:34 +0000 (15:25 +0200)]
perf top: fix typo in -d option
Clean up copy/paste options parsing conversion error.
[ Impact: reactivate -d option ]
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mike Galbraith [Tue, 26 May 2009 13:25:34 +0000 (15:25 +0200)]
perf top: Remove leftover NMI/IRQ bits
79202b removed IRQ/NMI mode selection, so remove it from
perf top as well.
[ Impact: cleanup ]
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 07:17:18 +0000 (09:17 +0200)]
perf report: Add help/manpage
Add a (minimal) manpage for perf report.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 07:17:18 +0000 (09:17 +0200)]
perf record: Convert to Git option parsing
Remove getopt usage and use Git's much more advanced and more compact
command option library.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Fri, 22 May 2009 13:34:54 +0000 (15:34 +0200)]
perf report: Fix segfault on unknown symbols
Ingo reported:
> Program received signal SIGSEGV, Segmentation fault.
> 0x0000003e25080f80 in strlen () from /lib64/libc.so.6
> Missing separate debuginfos, use: debuginfo-install elfutils.x86_64
> glibc.x86_64 zlib.x86_64
> (gdb) bt
> #0 0x0000003e25080f80 in strlen () from /lib64/libc.so.6
> #1 0x0000003e2506954e in fputs () from /lib64/libc.so.6
> #2 0x00000000004059e8 in cmd_report (argc=<value optimized out>,
> argv=<value optimized out>) at builtin-report.c:521
> #3 0x0000000000402dad in handle_internal_command (argc=1, argv=0x7fffe1218e30)
> at perf.c:226
> #4 0x0000000000402f6d in main (argc=1, argv=0x7fffe1218e30) at perf.c:324
> (gdb)
Signed-off-by Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Tue, 19 May 2009 12:30:23 +0000 (09:30 -0300)]
perf_counter: Use rb_tree for symhists and threads in report
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Mon, 18 May 2009 19:25:31 +0000 (16:25 -0300)]
perf_counter: Add our private copy of list.h
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Mon, 18 May 2009 19:24:49 +0000 (16:24 -0300)]
perf_counter: Use rb_trees in perf report
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Mon, 18 May 2009 17:28:47 +0000 (14:28 -0300)]
perf_counter: Implement dso__load using libelf
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Wed, 20 May 2009 10:45:34 +0000 (12:45 +0200)]
perf_counter tools: remove the standalone perf-report utility
With a built-in 'perf report' command now available, remove the
standalone implementation for good.
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arnaldo Carvalho de Melo [Mon, 18 May 2009 15:45:42 +0000 (12:45 -0300)]
perf_counter: First part of 'perf report' conversion to C + elfutils
Integrate perf-report into 'perf', as builtin-report.c.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 07:17:18 +0000 (09:17 +0200)]
perf top: Convert to Git option parsing
Remove getopt usage and use Git's much more advanced and more compact
command option library.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 07:17:18 +0000 (09:17 +0200)]
perf stat: Convert to Git option parsing
Remove getopt usage and use Git's much more advanced and more compact
command option library.
Extend the event parser library with the extensions that were in
perf-stat before.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 09:10:09 +0000 (11:10 +0200)]
perf_counter tools: Librarize event string parsing
Extract the event string parser from builtin-record.c, and
librarize it - to be reused in other commands.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 07:17:18 +0000 (09:17 +0200)]
perf record: Convert to Git option parsing
Remove getopt usage and use Git's much more advanced and more compact
command option library.
Git's library (util/parse-options.[ch]) constructs help texts and
error messages automatically, and has a number of other convenience
features as well.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 08:07:44 +0000 (10:07 +0200)]
perf stat: Remove unused variable
[ Impact: cleanup ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 07:02:27 +0000 (09:02 +0200)]
perf record: Straighten out argv types
[ Impact: cleanup ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 06:10:00 +0000 (08:10 +0200)]
perf_counter: Initialize ->oncpu properly
This shouldnt matter normally (and i have not seen any
misbehavior), because active counters always have a
proper ->oncpu value - but nevertheless initialize the
field properly to -1.
[ Impact: cleanup ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 06:10:00 +0000 (08:10 +0200)]
perf_counter, x86: Make NMI lockups more robust
We have a debug check that detects stuck NMIs and returns with
the PMU disabled in the global ctrl MSR - but i managed to trigger
a situation where this was not enough to deassert the NMI.
So clear/reset the full PMU and keep the disable count balanced when
exiting from here. This way the box produces a debug warning but
stays up and is more debuggable.
[ Impact: in case of PMU related bugs, recover more gracefully ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 26 May 2009 06:10:00 +0000 (08:10 +0200)]
perf_counter, x86: Fix APIC NMI programming
My Nehalem box locks up in certain situations (with an
always-asserted NMI causing a lockup) if the PMU LVT
entry is programmed between NMI and IRQ mode with a
high frequency.
Standardize exlusively on NMIs instead.
[ Impact: fix lockup ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Tue, 26 May 2009 06:27:59 +0000 (16:27 +1000)]
perf_counter: powerpc: Implement interrupt throttling
This implements interrupt throttling on powerpc. Since we don't have
individual count enable/disable or interrupt enable/disable controls
per counter, this simply sets the hardware counter to 0, meaning that
it will not interrupt again until it has counted 2^31 counts, which
will take at least 2^30 cycles assuming a maximum of 2 counts per
cycle. Also, we set counter->hw.period_left to the maximum possible
value (2^63 - 1), so we won't report overflows for this counter for
the forseeable future.
The unthrottle operation restores counter->hw.period_left and the
hardware counter so that we will once again report a counter overflow
after counter->hw.irq_period counts.
[ Impact: new perfcounters robustness feature on PowerPC ]
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <18971.35823.643362.446774@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Mon, 25 May 2009 20:03:26 +0000 (22:03 +0200)]
perf_counter: fix warning & lockup
- remove bogus warning
- fix wakeup from NMI path lockup
- also fix up whitespace noise in perf_counter.h
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525153931.
703093461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Mon, 25 May 2009 19:41:28 +0000 (21:41 +0200)]
Revert "perf_counter, x86: speed up the scheduling fast-path"
This reverts commit
b68f1d2e7aa21029d73c7d453a8046e95d351740.
It is causing problems (stuck/stuttering profiling) - when mixed
NMI and non-NMI counters are used.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525153931.
703093461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Mon, 25 May 2009 15:39:05 +0000 (17:39 +0200)]
perf_counter: Generic per counter interrupt throttle
Introduce a generic per counter interrupt throttle.
This uses the perf_counter_overflow() quick disable to throttle a specific
counter when its going too fast when a pmu->unthrottle() method is provided
which can undo the quick disable.
Power needs to implement both the quick disable and the unthrottle method.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525153931.
703093461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Mon, 25 May 2009 15:39:04 +0000 (17:39 +0200)]
perf_counter: x86: Remove interrupt throttle
remove the x86 specific interrupt throttle
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525153931.
616671838@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Mon, 25 May 2009 15:39:03 +0000 (17:39 +0200)]
perf_counter: x86: Expose INV and EDGE bits
Expose the INV and EDGE bits of the PMU to raw configs.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525153931.
494709027@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Mon, 25 May 2009 12:45:28 +0000 (14:45 +0200)]
perf_counter: Fix PERF_COUNTER_CONTEXT_SWITCHES for cpu counters
Ingo noticed that cpu counters had 0 context switches, even though
there was plenty scheduling on the cpu.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525124600.
419025548@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Mon, 25 May 2009 12:45:27 +0000 (14:45 +0200)]
perf_counter: Propagate inheritance failures down the fork() path
Fail fork() when we fail inheritance for some reason (-ENOMEM most likely).
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525124600.
324656474@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Mon, 25 May 2009 12:45:26 +0000 (14:45 +0200)]
perf_counter: Make pctrl() affect inherited counters too
Paul noted that the new ptcrl() didn't work on child counters.
Reported-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525124600.
203151469@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Mon, 25 May 2009 12:45:25 +0000 (14:45 +0200)]
perf_counter: Remove unused ABI bits
extra_config_len isn't used for anything, remove it.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525124600.
116035832@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Mon, 25 May 2009 12:45:24 +0000 (14:45 +0200)]
perf_counter: Fix perf-$cmd invokation
Fix:
$ perf-top
fatal: cannot handle -top internally
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090525124559.
995591577@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Mon, 25 May 2009 12:40:01 +0000 (14:40 +0200)]
perf stat: flip around ':k' and ':u' flags
This output:
$ perf stat -e 0:1:k -e 0:1:u ./hello
Performance counter stats for './hello':
140131 instructions (events)
1906968 instructions (events)
Is quite confusing - as :k means "user instructions", :u means
"kernel instructions".
Flip them around - as the 'exclude' property is not intuitive in
the flag naming.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Tue, 19 May 2009 13:50:30 +0000 (15:50 +0200)]
perf_counter: Move child perfcounter init to after scheduler init
Initialize a task's perfcounters (inherit from parent, etc.) after
the child task's scheduler fields have been initialized already.
[ Impact: cleanup ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mike Galbraith [Mon, 25 May 2009 07:57:56 +0000 (09:57 +0200)]
perf top: Reduce display overhead
Iterate over the symbol table once per display interval, and
copy/sort/tally/decay only those symbols which are active.
Before:
top - 10:14:53 up 4:08, 17 users, load average: 1.17, 1.53, 1.49
Tasks: 273 total, 5 running, 268 sleeping, 0 stopped, 0 zombie
Cpu(s): 6.9%us, 38.2%sy, 0.0%ni, 19.9%id, 0.0%wa, 0.0%hi, 35.0%si, 0.0%st
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ P COMMAND
28504 root 20 0 1044 260 164 S 58 0.0 0:04.19 2 netserver
28499 root 20 0 1040 412 316 R 51 0.0 0:04.15 0 netperf
28500 root 20 0 1040 408 316 R 50 0.0 0:04.14 1 netperf
28503 root 20 0 1044 260 164 S 50 0.0 0:04.01 1 netserver
28501 root 20 0 1044 260 164 S 49 0.0 0:03.99 0 netserver
28502 root 20 0 1040 412 316 S 43 0.0 0:03.96 2 netperf
28468 root 20 0 1892m 325m 972 S 16 10.8 0:10.50 3 perf
28467 root 20 0 1892m 325m 972 R 2 10.8 0:00.72 3 perf
After:
top - 10:16:30 up 4:10, 17 users, load average: 2.27, 1.88, 1.62
Tasks: 273 total, 6 running, 267 sleeping, 0 stopped, 0 zombie
Cpu(s): 2.5%us, 39.7%sy, 0.0%ni, 24.6%id, 0.0%wa, 0.0%hi, 33.3%si, 0.0%st
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ P COMMAND
28590 root 20 0 1040 412 316 S 54 0.0 0:07.85 2 netperf
28589 root 20 0 1044 260 164 R 54 0.0 0:07.84 0 netserver
28588 root 20 0 1040 412 316 R 50 0.0 0:07.89 1 netperf
28591 root 20 0 1044 256 164 S 50 0.0 0:07.82 1 netserver
28587 root 20 0 1040 408 316 R 47 0.0 0:07.61 0 netperf
28592 root 20 0 1044 260 164 R 47 0.0 0:07.85 2 netserver
28378 root 20 0 8732 1300 860 R 2 0.0 0:01.81 3 top
28577 root 20 0 1892m 165m 972 R 2 5.5 0:00.48 3 perf
28578 root 20 0 1892m 165m 972 S 2 5.5 0:00.04 3 perf
[ Impact: optimization ]
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Mon, 25 May 2009 07:59:50 +0000 (09:59 +0200)]
perf_counter tools: increase limits, fix
NR_CPUS and NR_COUNTERS goes up quadratic ... 1024x4096 was far
too ambitious upper limit - go for 256x256 which is still plenty.
[ Impact: reduce perf tool memory consumption ]
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Sun, 24 May 2009 07:02:37 +0000 (09:02 +0200)]
perf_counter: Increase mmap limit
In a default 'perf top' run the tool will create a counter for
each online CPU. With enough CPUs this will eventually exhaust
the default limit.
So scale it up with the number of online CPUs.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mike Galbraith [Sun, 24 May 2009 06:35:49 +0000 (08:35 +0200)]
perf top: fix segfault
c6eb13 increased stack usage such that perf-top now croaks on startup.
Take event_array and mmap_array off the stack to prevent segfault on boxen
with smallish ulimit -s setting.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Sat, 23 May 2009 16:29:01 +0000 (18:29 +0200)]
perf_counter: Remove perf_counter_context::nr_enabled
now that pctrl() no longer disables other people's counters,
remove the PMU cache code that deals with that.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090523163013.
032998331@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Sat, 23 May 2009 16:29:00 +0000 (18:29 +0200)]
perf_counter: Change pctrl() behaviour
Instead of en/dis-abling all counters acting on a particular
task, en/dis- able all counters we created.
[ v2: fix crash on first counter enable ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090523163012.
916937244@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Sat, 23 May 2009 16:28:59 +0000 (18:28 +0200)]
perf_counter: Simplify context cleanup
Use perf_counter_remove_from_context() to remove counters from
the context.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090523163012.
796275849@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Sat, 23 May 2009 16:28:58 +0000 (18:28 +0200)]
perf_counter: Fix userspace build
recent userspace (F11) seems to already include the
linux/unistd.h bits which means we cannot include the version
in the kernel sources due to the header guards being the same.
Ensure we include the kernel version first.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090523163012.
739756497@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Sat, 23 May 2009 16:28:57 +0000 (18:28 +0200)]
perf_counter: Sanitize context locking
Ensure we're consistent with the context locks.
context->mutex
context->lock
list_{add,del}_counter();
so that either lock is sufficient to stabilize the context.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090523163012.
618790733@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Sat, 23 May 2009 16:28:56 +0000 (18:28 +0200)]
perf_counter: Sanitize counter->mutex
s/counter->mutex/counter->child_mutex/ and make sure its only
used to protect child_list.
The usage in __perf_counter_exit_task() doesn't appear to be
problematic since ctx->mutex also covers anything related to fd
tear-down.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090523163012.
533186528@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra [Sat, 23 May 2009 16:28:55 +0000 (18:28 +0200)]
perf_counter: Fix dynamic irq_period logging
We call perf_adjust_freq() from perf_counter_task_tick() which
is is called under the rq->lock causing lock recursion.
However, it's no longer required to be called under the
rq->lock, so remove it from under it.
Also, fix up some related comments.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <
20090523163012.
476197912@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Fri, 22 May 2009 16:18:28 +0000 (18:18 +0200)]
perf_counter tools: increase limits
I tried to run with 300 active counters and the tools bailed out
because our limit was at 64. So increase the counter limit to 1024
and the CPU limit to 4096.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Fri, 22 May 2009 10:32:15 +0000 (12:32 +0200)]
perf_counter: fix !PERF_COUNTERS build failure
Update the !CONFIG_PERF_COUNTERS prototype too, for
perf_counter_task_sched_out().
[ Impact: build fix ]
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <18966.10666.517218.332164@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Fri, 22 May 2009 04:27:22 +0000 (14:27 +1000)]
perf_counter: Optimize context switch between identical inherited contexts
When monitoring a process and its descendants with a set of inherited
counters, we can often get the situation in a context switch where
both the old (outgoing) and new (incoming) process have the same set
of counters, and their values are ultimately going to be added together.
In that situation it doesn't matter which set of counters are used to
count the activity for the new process, so there is really no need to
go through the process of reading the hardware counters and updating
the old task's counters and then setting up the PMU for the new task.
This optimizes the context switch in this situation. Instead of
scheduling out the perf_counter_context for the old task and
scheduling in the new context, we simply transfer the old context
to the new task and keep using it without interruption. The new
context gets transferred to the old task. This means that both
tasks still have a valid perf_counter_context, so no special case
is introduced when the old task gets scheduled in again, either on
this CPU or another CPU.
The equivalence of contexts is detected by keeping a pointer in
each cloned context pointing to the context it was cloned from.
To cope with the situation where a context is changed by adding
or removing counters after it has been cloned, we also keep a
generation number on each context which is incremented every time
a context is changed. When a context is cloned we take a copy
of the parent's generation number, and two cloned contexts are
equivalent only if they have the same parent and the same
generation number. In order that the parent context pointer
remains valid (and is not reused), we increment the parent
context's reference count for each context cloned from it.
Since we don't have individual fds for the counters in a cloned
context, the only thing that can make two clones of a given parent
different after they have been cloned is enabling or disabling all
counters with prctl. To account for this, we keep a count of the
number of enabled counters in each context. Two contexts must have
the same number of enabled counters to be considered equivalent.
Here are some measurements of the context switch time as measured with
the lat_ctx benchmark from lmbench, comparing the times obtained with
and without this patch series:
-----Unmodified----- With this patch series
Counters: none 2 HW 4H+4S none 2 HW 4H+4S
2 processes:
Average 3.44 6.45 11.24 3.12 3.39 3.60
St dev 0.04 0.04 0.13 0.05 0.17 0.19
8 processes:
Average 6.45 8.79 14.00 5.57 6.23 7.57
St dev 1.27 1.04 0.88 1.42 1.46 1.42
32 processes:
Average 5.56 8.43 13.78 5.28 5.55 7.15
St dev 0.41 0.47 0.53 0.54 0.57 0.81
The numbers are the mean and standard deviation of 20 runs of
lat_ctx. The "none" columns are lat_ctx run directly without any
counters. The "2 HW" columns are with lat_ctx run under perfstat,
counting cycles and instructions. The "4H+4S" columns are lat_ctx run
under perfstat with 4 hardware counters and 4 software counters
(cycles, instructions, cache references, cache misses, task
clock, context switch, cpu migrations, and page faults).
[ Impact: performance optimization of counter context-switches ]
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <18966.10666.517218.332164@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Paul Mackerras [Fri, 22 May 2009 04:17:31 +0000 (14:17 +1000)]
perf_counter: Dynamically allocate tasks' perf_counter_context struct
This replaces the struct perf_counter_context in the task_struct with
a pointer to a dynamically allocated perf_counter_context struct. The
main reason for doing is this is to allow us to transfer a
perf_counter_context from one task to another when we do lazy PMU
switching in a later patch.
This has a few side-benefits: the task_struct becomes a little smaller,
we save some memory because only tasks that have perf_counters attached
get a perf_counter_context allocated for them, and we can remove the
inclusion of <linux/perf_counter.h> in sched.h, meaning that we don't
end up recompiling nearly everything whenever perf_counter.h changes.
The perf_counter_context structures are reference-counted and freed
when the last reference is dropped. A context can have references
from its task and the counters on its task. Counters can outlive the
task so it is possible that a context will be freed well after its
task has exited.
Contexts are allocated on fork if the parent had a context, or
otherwise the first time that a per-task counter is created on a task.
In the latter case, we set the context pointer in the task struct
locklessly using an atomic compare-and-exchange operation in case we
raced with some other task in creating a context for the subject task.
This also removes the task pointer from the perf_counter struct. The
task pointer was not used anywhere and would make it harder to move a
context from one task to another. Anything that needed to know which
task a counter was attached to was already using counter->ctx->task.
The __perf_counter_init_context function moves up in perf_counter.c
so that it can be called from find_get_context, and now initializes
the refcount, but is otherwise unchanged.
We were potentially calling list_del_counter twice: once from
__perf_counter_exit_task when the task exits and once from
__perf_counter_remove_from_context when the counter's fd gets closed.
This adds a check in list_del_counter so it doesn't do anything if
the counter has already been removed from the lists.
Since perf_counter_task_sched_in doesn't do anything if the task doesn't
have a context, and leaves cpuctx->task_ctx = NULL, this adds code to
__perf_install_in_context to set cpuctx->task_ctx if necessary, i.e. in
the case where the current task adds the first counter to itself and
thus creates a context for itself.
This also adds similar code to __perf_counter_enable to handle a
similar situation which can arise when the counters have been disabled
using prctl; that also leaves cpuctx->task_ctx = NULL.
[ Impact: refactor counter context management to prepare for new feature ]
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <18966.10075.781053.231153@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>