linux-stable.git/tools/perf/Documentation, branch linux-4.5.y

perf stat: Document --detailed option

2016-05-04T21:49:14+00:00

commit f594bae08183fb6b57db55387794ece3e1edf6f6 upstream.

I'm surprised this remained undocumented since at least 2011. And it is
actually a very useful switch, as Steve and I came to realize recently.

Add the text from

  2cba3ffb9a9d ("perf stat: Add -d -d and -d -d -d options to show more CPU events")

which added the incrementing aspect to -d.

Tested-by: Arnaldo Carvalho de Melo 
Signed-off-by: Borislav Petkov 
Signed-off-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: David Ahern 
Cc: Davidlohr Bueso 
Cc: Jiri Olsa 
Cc: Mel Gorman 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Cc: Thomas Gleixner 
Fixes: 2cba3ffb9a9d ("perf stat: Add -d -d and -d -d -d options to show more CPU events")
Link: http://lkml.kernel.org/r/1457347294-32546-1-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

perf tools: Add more usage tips

2016-01-12T15:42:07+00:00

Thanks to Andi Kleen for providing useful tips.

Suggested-by: Andi Kleen 
Signed-off-by: Namhyung Kim 
Cc: Andi Kleen 
Cc: Brendan Gregg 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1452508510-28316-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf record: Add --buildid-all option

2016-01-12T15:42:07+00:00

The --buildid-all option is to record build-id of all DSOs in the file.
It might be very costly to postprocess samples to find which DSO hits.

Signed-off-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1452519429-31779-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Add --trace-fields option to show trace fields

2016-01-08T17:23:02+00:00

To use dynamic sort keys, it might be good to add an option to see the
list of field names.

  $ perf evlist -i perf.data.sched
  sched:sched_switch
  sched:sched_stat_wait
  sched:sched_stat_sleep
  sched:sched_stat_iowait
  sched:sched_stat_runtime
  sched:sched_process_fork
  sched:sched_wakeup
  sched:sched_wakeup_new
  sched:sched_migrate_task
  # Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events

  $ perf evlist -i perf.data.sched --trace-fields
  sched:sched_switch: trace_fields: prev_comm,prev_pid,prev_prio,prev_state,next_comm,next_pid,next_prio
  sched:sched_stat_wait: trace_fields: comm,pid,delay
  sched:sched_stat_sleep: trace_fields: comm,pid,delay
  sched:sched_stat_iowait: trace_fields: comm,pid,delay
  sched:sched_stat_runtime: trace_fields: comm,pid,runtime,vruntime
  sched:sched_process_fork: trace_fields: parent_comm,parent_pid,child_comm,child_pid
  sched:sched_wakeup: trace_fields: comm,pid,prio,success,target_cpu
  sched:sched_wakeup_new: trace_fields: comm,pid,prio,success,target_cpu
  sched:sched_migrate_task: trace_fields: comm,pid,prio,orig_cpu,dest_cpu

Committer notes:

For another file, in verbose mode:

  # perf evlist -v --trace-fields
  sched:sched_switch: type: 2, size: 112, config: 0x10b, { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|CPU|PERIOD|RAW, disabled: 1, inherit: 1, mmap: 1, comm: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, trace_fields: prev_comm,prev_pid,prev_prio,prev_state,next_comm,next_pid,next_prio
  #

Signed-off-by: Namhyung Kim 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1452125549-1511-5-git-send-email-namhyung@kernel.org
[ Replaced 'trace_fields=' with 'trace_fields: ' to make the output consistent in -v mode ]
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Show random usage tip on the help line

2016-01-08T16:15:46+00:00

Currently perf report only shows a help message "For a higher level
overview, try: perf report --sort comm,dso" unconditionally (even if
the sort keys were used).  Add more help tips and show randomly.

Load tips from ${prefix}/share/doc/perf-tip/tips.txt file.

  $ perf report | tail
      0.10%  swapper  [kernel.vmlinux]   [k] irq_exit
      0.09%  swapper  [kernel.vmlinux]   [k] flush_smp_call_function_queue
      0.08%  swapper  [kernel.vmlinux]   [k] native_write_msr_safe
      0.03%  swapper  [kernel.vmlinux]   [k] group_sched_in
      0.01%  perf     [kernel.vmlinux]   [k] native_write_msr_safe

  #
  # (Tip: Search options using a keyword: perf report -h )
  #

Signed-off-by: Namhyung Kim 
Acked-by: Ingo Molnar 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1452166913-27046-1-git-send-email-namhyung@kernel.org
[ Renamed it to perf_tip() and the parameter dirname to dirpath to fix the build on older distros ]
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Add documentation for dynamic sort keys

2016-01-06T23:11:14+00:00

Signed-off-by: Namhyung Kim 
Acked-by: Jiri Olsa 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1451991518-25673-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf report/top: Add --raw-trace option

2016-01-06T23:11:12+00:00

The --raw-trace option allows disabling pretty printing by the event's
print_fmt or plugin.  Besides that, each dynamic sort key now can
receive a 'raw' suffix separated by '/' to ask for the raw trace of a
specific field.

  $ perf report -s comm,kmem:kmalloc.gfp_flags
  ...
  # Overhead  Command            gfp_flags
  # ........  .......  ...................
  #
      99.89%  perf       GFP_NOFS|GFP_ZERO
       0.06%  sleep             GFP_KERNEL
       0.03%  perf     GFP_KERNEL|GFP_ZERO
       0.01%  perf              GFP_KERNEL

Now

  $ perf report -s comm,kmem:kmalloc.gfp_flags --raw-trace
or
  $ perf report -s comm,kmem:kmalloc.gfp_flags/raw
  ...
  # Overhead  Command   gfp_flags
  # ........  .......  ..........
  #
      99.89%  perf          32848
       0.06%  sleep           208
       0.03%  perf          32976
       0.01%  perf            208

Suggested-and-Acked-by: Jiri Olsa 
Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Andi Kleen 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Cc: Wang Nan 
Link: http://lkml.kernel.org/r/1450804030-29193-9-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf stat report: Allow to override aggr_mode

2015-12-17T19:30:30+00:00

Allowing to override record aggr_mode. It's possible to use perf stat
like:

   $ perf stat report -A
   $ perf stat report --per-core
   $ perf stat report --per-socket

To customize the recorded aggregate mode regardless what was used during
the stat record command.

Reported-by: Kan Liang 
Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1446734469-11352-19-git-send-email-jolsa@kernel.org
[ Renamed 'stat' parameter to 'st' to fix 'already defined' build error with older distros (e.g. RHEL6.7) ]
Signed-off-by: Arnaldo Carvalho de Melo

perf stat report: Add report command

2015-12-17T19:00:34+00:00

Adding 'perf stat report' command support. ATM it only processes attr
events and display nothing.

Reported-by: Kan Liang 
Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1446734469-11352-12-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf stat record: Add record command

2015-12-17T18:15:15+00:00

Add 'perf stat record' command support. It creates simple (header only)
perf.data file ATM.

The record command could be specified anywhere among stat options. All
stat command options are valid for stat record command with '-o' option
exception. If specified for record command it denotes the perf data file
name.

Committer note:

Set sample_type to PERF_SAMPLE_IDENTIFIER, which should be harmless
while avoiding that older tools show confusing messages, for instance,
with sample_type = 0, we get:

  $ perf stat record usleep 1

   Performance counter stats for 'usleep 1':

          0.630237      task-clock (msec)         #    0.528 CPUs utilized
                 1      context-switches          #    0.002 M/sec
                 0      cpu-migrations            #    0.000 K/sec
                52      page-faults               #    0.083 M/sec
           978,312      cycles                    #    1.552 GHz
           671,931      stalled-cycles-frontend   #   68.68% frontend cycles idle
         stalled-cycles-backend
           646,379      instructions              #    0.66  insns per cycle
                                                  #    1.04  stalled cycles per insn
           131,046      branches                  #  207.931 M/sec
             7,073      branch-misses             #    5.40% of all branches

       0.001193240 seconds time elapsed

  $ oldperf evlist
  WARNING: The perf.data file's data size field is 0 which is unexpected.
  Was the 'perf record' command properly terminated?
  non matching sample_type
  $

While with sample_type set to PERF_SAMPLE_IDENTIFIER, after we re-run 'perf
stat record usleep' we get:

  $ oldperf evlist
  WARNING: The perf.data file's data size field is 0 which is unexpected.
  Was the 'perf record' command properly terminated?
  task-clock
  context-switches
  cpu-migrations
  page-faults
  cycles
  stalled-cycles-frontend
  stalled-cycles-backend
  instructions
  branches
  branch-misses
  $

Which at least shows the names of the events in the perf.data file.

Additionally, such files, when passed to 'perf report' will produce:

  $ oldperf report --stdio
  WARNING: The perf.data file's data size field is 0 which is unexpected.
  Was the 'perf record' command properly terminated?
  Warning:
  Kernel address maps (/proc/{kallsyms,modules}) were restricted.

  Check /proc/sys/kernel/kptr_restrict before running 'perf record'.

  As no suitable kallsyms nor vmlinux was found, kernel samples
  can't be resolved.

  Samples in kernel modules can't be resolved as well.

  Error:
  The perf.data file has no samples!
  # To display the perf.data header info, please use --header/--header-only options.
  #
  $

Which is confusing and can be solved by just adding the kernel mmap record,
which will also remove that warning about the data size field being equal to
zero, after generating the mmap record:

  $ perf stat record usleep 1

   Performance counter stats for 'usleep 1':

          0.600796      task-clock (msec)         #    0.478 CPUs utilized
                 1      context-switches          #    0.002 M/sec
                 0      cpu-migrations            #    0.000 K/sec
                54      page-faults               #    0.090 M/sec
           886,844      cycles                    #    1.476 GHz
           582,169      stalled-cycles-frontend   #   65.65% frontend cycles idle
         stalled-cycles-backend
           638,344      instructions              #    0.72  insns per cycle
                                                  #    0.91  stalled cycles per insn
           130,204      branches                  #  216.719 M/sec
             7,500      branch-misses             #    5.76% of all branches

       0.001255897 seconds time elapsed

  $ oldperf evlist
  task-clock
  context-switches
  cpu-migrations
  page-faults
  cycles
  stalled-cycles-frontend
  stalled-cycles-backend
  instructions
  branches
  branch-misses
  $ oldperf report --stdio
  Error:
  The perf.data file has no samples!
  # To display the perf.data header info, please use --header/--header-only options.
  #
  [acme@zoo linux]$

No warnings, sensible output about what are the events in the perf.data file and also
a "file has no samples" message, which indeed it doesn't.

Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Tested-by: Kan Liang 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: htp://lkml.kernel.org/r/1446734469-11352-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo