linux-stable.git/tools/perf/Documentation, branch linux-4.18.y

perf stat: Add --interval-clear option

2018-06-07T18:53:36+00:00

Adding --interval-clear option to clear the screen before next interval.

Committer testing:

  # perf stat -I 1000 --interval-clear

And, as expected, it behaves almost like:

  # watch -n 0 perf stat -a sleep 1

Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Milian Wolff 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/20180606221513.11302-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf script python: Add dict fields introduction to Documentation

2018-06-06T18:40:10+00:00

Add a brief introduction about fields to perf-script-python.txt.

It should help python script developers in easily finding what fields
are supported.

Signed-off-by: Jin Yao 
Reviewed-by: Andi Kleen 
Cc: Alexander Shishkin 
Cc: Jin Yao 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1527843663-32288-4-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Display user and system time

2018-06-06T15:52:04+00:00

Adding the support to read rusage data once the workload is finished and
display the system/user time values:

  $ perf stat --null perf bench sched pipe
  ...

   Performance counter stats for 'perf bench sched pipe':

       5.342599256 seconds time elapsed

       2.544434000 seconds user
       4.549691000 seconds sys

It works only in non -r mode and only for workload target.

So as of now, for workload targets, we display 3 types of timings. The
time we meassure in perf stat from enable to disable+period:

       5.342599256 seconds time elapsed

The time spent in user and system lands, displayed only for workload
session/target:

       2.544434000 seconds user
       4.549691000 seconds sys

Those times are the very same displayed by 'time' tool.  They are
returned by wait4 call via the getrusage struct interface.

Committer notes:

Had to rename some variables to avoid this on older systems such as
centos:6:

  builtin-stat.c: In function 'print_footer':
  builtin-stat.c:1831: warning: declaration of 'stime' shadows a global declaration
  /usr/include/time.h:297: warning: shadowed declaration is here

Committer testing:

  # perf stat --null time perf bench sched pipe
  # Running 'sched/pipe' benchmark:
  # Executed 1000000 pipe operations between two processes

       Total time: 5.526 [sec]

         5.526534 usecs/op
           180945 ops/sec
  1.00user 6.25system 0:05.52elapsed 131%CPU (0avgtext+0avgdata 8056maxresident)k
  0inputs+0outputs (0major+606minor)pagefaults 0swaps

   Performance counter stats for 'time perf bench sched pipe':

         5.530978744 seconds time elapsed

         1.004037000 seconds user
         6.259937000 seconds sys

  #

Suggested-by: Ingo Molnar 
Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20180605121313.31337-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf record: Enable arbitrary event names thru name= modifier

2018-06-06T15:52:04+00:00

Enable complex event names containing [.:=,] symbols to be encoded into Perf
trace using name= modifier e.g. like this:

  perf record -e cpu/name=\'OFFCORE_RESPONSE:request=DEMAND_RFO:response=L3_HIT.SNOOP_HITM\',\
		  period=0x3567e0,event=0x3c,cmask=0x1/Duk ./futex

Below is how it looks like in the report output. Please note explicit escaped
quoting at cmdline string in the header so that thestring can be directly reused
for another collection in shell:

perf report --header

  # ========
  ...
  # cmdline : /root/abudanko/kernel/tip/tools/perf/perf record -v -e cpu/name=\'OFFCORE_RESPONSE:request=DEMAND_RFO:response=L3_HIT.SNOOP_HITM\',period=0x3567e0,event=0x3c,cmask=0x1/Duk ./futex
  # event : name = OFFCORE_RESPONSE:request=DEMAND_RFO:response=L3_HIT.SNOOP_HITM, , type = 4, size = 112, config = 0x100003c, { sample_period, sample_freq } = 3500000, sample_type = IP|TID|TIME, disabled = 1, inh
  ...
  # ========
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 24K of event 'OFFCORE_RESPONSE:request=DEMAND_RFO:response=L3_HIT.SNOOP_HITM'
  # Event count (approx.): 86492000000
  #
  # Overhead  Command  Shared Object     Symbol
  # ........  .......  ................  ..............................................
  #
      14.75%  futex    [kernel.vmlinux]  [k] __entry_trampoline_start
...

  perf stat -e cpu/name=\'CPU_CLK_UNHALTED.THREAD:cmask=0x1\',period=0x3567e0,event=0x3c,cmask=0x1/Duk ./futex

  10000000 process context switches in 16678890291ns (1667.9ns/ctxsw)

   Performance counter stats for './futex':

      88,095,770,571      CPU_CLK_UNHALTED.THREAD:cmask=0x1

        16.679542407 seconds time elapsed

Signed-off-by: Alexey Budankov 
Acked-by: Andi Kleen 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/c194b060-761d-0d50-3b21-bb4ed680002d@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

Merge remote-tracking branch 'tip/perf/urgent' into perf/core

2018-06-04T13:28:20+00:00

To pick up fixes.

Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix perf.data format description of NRCPUS header

2018-05-30T18:40:26+00:00

In the perf.data HEADER_CPUDESC feadure header we store first the number
of available CPUs in the system, then the number of CPUs at the time of
writing the header, not the other way around.

Reported-by: Thomas-Mich Richter 
Acked-by: Andi Kleen 
Cc: Adrian Hunter 
Cc: David Ahern 
Cc: He Kuang 
Cc: Hendrik Brueckner 
Cc: Jin Yao 
Cc: Jiri Olsa 
Cc: Kim Phillips 
Cc: Lakshman Annadorai 
Cc: Namhyung Kim 
Cc: Simon Que 
Cc: Stephane Eranian 
Cc: Wang Nan 
Link: https://lkml.kernel.org/n/tip-j7o92acm2vnxjv70y4o3swoc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf data: Update documentation section on cpu topology

2018-05-30T18:39:13+00:00

Add an explanation of each cpu's core and socket identifier to the
perf.data file format documentation.

Signed-off-by: Thomas Richter 
Cc: Heiko Carstens 
Cc: Hendrik Brueckner 
Cc: Martin Schwidefsky 
Link: http://lkml.kernel.org/r/20180528074433.16652-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo

perf Documentation: Support for asciidoctor

2018-04-26T16:47:10+00:00

The asciidoc package seems behind the recent big wave of python3
conversion, and we were advised to switch to asciidoctor instead.  It's
almost compatible but some extensions used for perf documentation don't
work with it.  Here is the patch to cover them, and add the proper
support for asciidoctor.

Pass USE_ASCIIDOCTOR=yes to make for using asciidoctor instead of
asciidoc.  The man source and manual attributes are passed via command
options.  The support for these attributes have been fixed in the
latest asciidoctor code.

Since asciidoctor can covert to a man page and an HTML directly, we
can omit the dependency on xmlto when USE_ASCIIDOCTOR is set.

Signed-off-by: Takashi Iwai 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20180424150456.17353-1-tiwai@suse.de
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Display length strings of each run for --table option

2018-04-26T12:30:27+00:00

Adding support to display visual aid 'length strings' to easily spot the
biggest difference in time table.

  $ perf stat -r 10 --table perf bench sched pipe
  ...

   Performance counter stats for './perf bench sched pipe' (5 runs):

             # Table of individual measurements:
             5.189 (-0.293) #
             5.189 (-0.294) #
             5.186 (-0.296) #
             5.663 (+0.181) ##
             6.186 (+0.703) ####

             # Final result:
             5.483 +- 0.198 seconds time elapsed  ( +-  3.62% )

Suggested-by: Ingo Molnar 
Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20180423090823.32309-9-jolsa@kernel.org
[ Updated 'perf stat --table' man page entry ]
Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add --table option to display time of each run

2018-04-26T12:30:27+00:00

Add --table option to display time for each run (-r option), like:

  $ perf stat --null -r 5 --table perf bench sched pipe

   Performance counter stats for './perf bench sched pipe' (5 runs):

             # Table of individual measurements:
             5.379 (-0.176)
             5.243 (-0.311)
             5.238 (-0.317)
             5.536 (-0.019)
             6.377 (+0.823)

             # Final result:
             5.555 +- 0.213 seconds time elapsed  ( +-  3.83% )

Suggested-by: Ingo Molnar 
Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20180423090823.32309-8-jolsa@kernel.org
[ Document the new option in 'perf stat's man page ]
Signed-off-by: Arnaldo Carvalho de Melo