linux.git/tools/perf/builtin-stat.c, branch v3.2

perf stat: Failure with "Operation not supported"

2011-12-05T16:32:40+00:00

perf stat is failing on PowerPC:

  Error: open_counter returned with 95 (Operation not supported). /bin/dmesg may provide additional information.

  Fatal: Not all events could be opened.

commit 370faf1dd046 (perf stat: Fail softly on unsupported events)
added a check for failure returning ENOENT, but the POWER backend
returns EOPNOTSUPP. It looks like alpha, blackfin and mips do the
same.

With the patch applied, things work as expected:

 Performance counter stats for '/bin/true':

          0.362176 task-clock                #    0.623 CPUs utilized
                 0 context-switches          #    0.000 M/sec
                 0 CPU-migrations            #    0.000 M/sec
                28 page-faults               #    0.077 M/sec
         1,677,020 cycles                    #    4.630 GHz
    stalled-cycles-frontend
    stalled-cycles-backend
           431,220 instructions              #    0.26  insns per cycle
           101,889 branches                  #  281.325 M/sec
             4,145 branch-misses             #    4.07% of all branches

       0.000581361 seconds time elapsed

Cc:  # 3.0+
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20111202093833.5fef7226@kryten
Signed-off-by: Anton Blanchard 
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Fix grouping of multiple events

2011-10-26T12:25:02+00:00

The __perf_evsel__open routing was grouping just the threads for that
specific events per cpu when we want to group all threads in all events
to the first fd opened on that cpu.

So pass the xyarray with the first event, where the other events will be
able to get that first per cpu fd.

At some point top and record will switch to using perf_evlist__open that
takes care of this detail and probably will also handle the fallback
from hw to soft counters, etc.

Reported-by: Deng-Cheng Zhu 
Tested-by: Deng-Cheng Zhu 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-ebm34rh098i9y9v4cytfdp0x@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Make stat/record print fatal signals of the target program

2011-09-29T20:09:46+00:00

When a program crashes under perf there is no message about it, unlike
when running it from bash. This can be confusing and lead to wrong
actions during debugging.

Print fatal signals in perf stat/record.

Thanks to Furat Afram for finding the problem originally

Link: http://lkml.kernel.org/r/1316122302-24306-1-git-send-email-andi@firstfloor.org
Cc: Frederic Weisbecker 
Cc: Stephane Eranian 
Signed-off-by: Andi Kleen 
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Fix spelling in comment

2011-09-29T20:09:36+00:00

Link: http://lkml.kernel.org/r/1315437244-3788-6-git-send-email-jim.cromie@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Jim Cromie 
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Allow tab as cvs delimiter

2011-09-29T20:04:30+00:00

If option -x '\t' is given, convert '\t' to "\t".  This makes cvs
printing more flexible.

Link: http://lkml.kernel.org/r/1315437244-3788-5-git-send-email-jim.cromie@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Jim Cromie 
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Suppress printing std-dev when its 0

2011-09-29T20:04:00+00:00

For pretty output only (preserve column for cvs output), dont print
std-deviation when its 0.00.  Do this based upon value, instead of
checking for --no-aggr, since the stats could conceivably be computed
over the runs on each CPU, and theres no reason to preclude that.

Link: http://lkml.kernel.org/r/1315437244-3788-4-git-send-email-jim.cromie@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Jim Cromie 
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Fix +- nan% in --no-aggr runs

2011-09-29T20:03:46+00:00

Without this patch, running:

$ sudo ./perf stat -r20 --no-aggr -a perl -e '$i++ for 1..100000'

I get computations like this:

CPU0             12.488247 task-clock                #    1.224 CPUs utilized            ( +-  -nan% )
CPU1             12.488909 task-clock                #    1.225 CPUs utilized            ( +-  -nan% )
CPU2             12.500221 task-clock                #    1.226 CPUs utilized            ( +-  -nan% )
CPU3             12.481713 task-clock                #    1.224 CPUs utilized            ( +-  -nan% )

but with patch, I get:

CPU0              8.233682 task-clock                #    0.754 CPUs utilized            ( +-  0.00% )
CPU1              8.226318 task-clock                #    0.754 CPUs utilized            ( +-  0.00% )
CPU2              8.210737 task-clock                #    0.752 CPUs utilized            ( +-  0.00% )
CPU3              8.201691 task-clock                #    0.751 CPUs utilized            ( +-  0.00% )

Note that without --no-aggr, I get non-0 statistics both before and after patch:

        231.986022 task-clock                #    4.030 CPUs utilized            ( +-  0.97% )
               212 context-switches          #    0.001 M/sec                    ( +- 12.07% )
                 9 CPU-migrations            #    0.000 M/sec                    ( +- 25.80% )
               466 page-faults               #    0.002 M/sec                    ( +-  3.23% )
       174,318,593 cycles                    #    0.751 GHz                      ( +-  1.06% )

I couldnt see anything wrong in the caller, so fixed it in
stddev_stats().  ISTM that 0.00 is better than nan, since perf stat was
passed -A (--no-aggr) so no standard deviation should be expected, and
nan is suggestive of a deeper error.

When running with --no-aggr, perhaps we should suppress the statistics
printing entirely, or do so when they are 0.00.

Link: http://lkml.kernel.org/r/1315437244-3788-3-git-send-email-jim.cromie@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Jim Cromie 
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add --log-fd option to redirect stderr elsewhere

2011-09-29T20:03:23+00:00

This perf stat option emulates valgrind's --log-fd option, allowing the
user to send perf results elsewhere, and leaving stderr for use by the
program under test.  This complements --output file option, and is
mutually exclusive with it.

   3>results  perf stat --log-fd 3          -- $cmd
   3>>results perf stat --log-fd 3 --append -- $cmd

The perl distro's make test.valgrind target uses valgrind's --log-fd
option, I've adapted it to invoke perf also, and tested this patch
there.

Link: http://lkml.kernel.org/r/1315437244-3788-2-git-send-email-jim.cromie@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Jim Cromie 
Signed-off-by: Arnaldo Carvalho de Melo

Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

2011-08-18T19:58:46+00:00

Conflicts:
	tools/perf/builtin-stat.c

perf stat: Add -o and --append options

2011-08-18T10:46:13+00:00

This patch adds an option (-o) to save the output of perf stat into a
file. You could do this with perf record but not with perf stat.
Instead, you had to fiddle with stderr to save the counts into a
separate file.

The patch also adds the --append option so that results can be
concatenated into a single file across runs. Each run of the tool is
clearly separated by a comment line starting with a hash mark. The -A
option of perf record is already used by perf stat, so we only add a
long option.

$ perf stat -o res.txt date
$ cat res.txt

 Performance counter stats for 'date':

          0.791306 task-clock                #    0.668 CPUs utilized
                 2 context-switches          #    0.003 M/sec
                 0 CPU-migrations            #    0.000 M/sec
               197 page-faults               #    0.249 M/sec
           1878143 cycles                    #    2.373 GHz
    stalled-cycles-frontend
    stalled-cycles-backend
           1083367 instructions              #    0.58  insns per cycle
            193027 branches                  #  243.935 M/sec
              9014 branch-misses             #    4.67% of all branches

       0.001184746 seconds time elapsed

The option can be combined with -x to make the output file much easier
to parse.

Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20110815202233.GA18535@quad
Signed-off-by: Stephane Eranian 
Signed-off-by: Arnaldo Carvalho de Melo