History log of /linux-master/tools/perf/Documentation/perf-sched.txt
Revision Date Author Comments
# c30d630d 04-Dec-2019 David Ahern <dsahern@gmail.com>

perf sched timehist: Add support for filtering on CPU

Allow user to limit output to one or more CPUs. Really helpful on
systems with a large number of cpus.

Committer testing:

# perf sched record -a sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.765 MB perf.data (1412 samples) ]
[root@quaco ~]# perf sched timehist | head
Samples do not have callchains.
time cpu task name wait time sch delay run time
[tid/pid] (msec) (msec) (msec)
--------------- ------ ------------------------------ --------- --------- ---------
66307.802686 [0000] perf[13086] 0.000 0.000 0.000
66307.802700 [0000] migration/0[12] 0.000 0.001 0.014
66307.802766 [0001] perf[13086] 0.000 0.000 0.000
66307.802774 [0001] migration/1[15] 0.000 0.001 0.007
66307.802841 [0002] perf[13086] 0.000 0.000 0.000
66307.802849 [0002] migration/2[20] 0.000 0.001 0.008
66307.802913 [0003] perf[13086] 0.000 0.000 0.000
#
# perf sched timehist --cpu 2 | head
Samples do not have callchains.
time cpu task name wait time sch delay run time
[tid/pid] (msec) (msec) (msec)
--------------- ------ ------------------------------ --------- --------- ---------
66307.802841 [0002] perf[13086] 0.000 0.000 0.000
66307.802849 [0002] migration/2[20] 0.000 0.001 0.008
66307.964485 [0002] <idle> 0.000 0.000 161.635
66307.964811 [0002] CPU 0/KVM[3589/3561] 0.000 0.056 0.325
66307.965477 [0002] <idle> 0.325 0.000 0.666
66307.965553 [0002] CPU 0/KVM[3589/3561] 0.666 0.024 0.076
66307.966456 [0002] <idle> 0.076 0.000 0.903
#

Signed-off-by: David Ahern <dsahern@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20191204173925.66976-1-dsahern@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# e8103e44 10-Apr-2018 Takuya Yamamoto <tkydevel@gmail.com>

perf sched: Fix documentation for timehist

Fixed a incorrect option and usage to those shown by "perf sched timehist -h",
i.e. the default is really --call-graph, which is equivalent to -g.

Signed-off-by: Takuya Yamamoto <tkydevel@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/n/tip-8fzo0dlsi1mku5aqx8brep5s@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# ea66536a 07-Mar-2018 Takashi Iwai <tiwai@suse.de>

perf tools: Correct title markers for asciidoctor

I've tested to process the perf man pages with asciidoctor that is
picker than asciidoc, and it revealed minor syntax errors in some
documents. Namely, the title markers aren't aligned with the previous
line, hence asciidoctor didn't recognize as titles.

This patch corrects these markers to be processed properly.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180307105441.28512-1-tiwai@suse.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# e9b61e52 16-Nov-2017 Sihyeon Jang <uneedsihyeon@gmail.com>

perf sched: Document missing --force option

Add --force to the man page.

Signed-off-by: Sihyeon Jang <uneedsihyeon@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1510842367-11011-4-git-send-email-uneedsihyeon@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 0f59d7a3 01-Sep-2017 David Ahern <dsahern@gmail.com>

perf sched timehist: Add pid and tid options

Add options to only show event for specific pid(s) and tid(s).

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1504288152-19690-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 292c4a8f 13-Mar-2017 Brendan Gregg <bgregg@netflix.com>

perf sched timehist: Add --next option

The --next option shows the next task for each context switch, providing
more context for the sequence of scheduler events.

$ perf sched timehist --next | head
Samples do not have callchains.
time cpu task name waittime schdelay run time
[tid/pid] (msec) (msec) (msec)
---------- --- ---------- --------- ------ -----
374.793792 [0] <idle> 0.000 0.000 0.000 next: rngd[1524]
374.793801 [0] rngd[1524] 0.000 0.000 0.009 next: swapper/0[0]
374.794048 [7] <idle> 0.000 0.000 0.000 next: yes[30884]
374.794066 [7] yes[30884] 0.000 0.000 0.018 next: swapper/7[0]
374.794126 [2] <idle> 0.000 0.000 0.000 next: rngd[1524]
374.794140 [2] rngd[1524] 0.325 0.006 0.013 next: swapper/2[0]
374.794281 [3] <idle> 0.000 0.000 0.000 next: perf[31070]

Signed-off-by: Brendan Gregg <bgregg@netflix.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1489456589-32555-1-git-send-email-bgregg@netflix.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 414e050c 13-Jan-2017 Namhyung Kim <namhyung@kernel.org>

perf sched timehist: Add --state option

The --state option is to show task state when switched out. The state
is printed as a single character like in the /proc but I added 'I' for
idle state rather than 'R'.

$ perf sched timehist --state | head
Samples do not have callchains.
time cpu task name wait time sch delay run time state
[tid/pid] (msec) (msec) (msec)
-------- --- ----------------------- -------- ------------------ -----
1.753791 [3] <idle> 0.000 0.000 0.000 I
1.753834 [1] perf[27469] 0.000 0.000 0.000 S
1.753904 [3] perf[27470] 0.000 0.006 0.112 S
1.753914 [1] <idle> 0.000 0.000 0.079 I
1.753915 [3] migration/3[23] 0.000 0.002 0.011 S
1.754287 [2] <idle> 0.000 0.000 0.000 I
1.754335 [2] transmission[1773/1739] 0.000 0.004 0.047 S

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170113104523.31212-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 07235f84 08-Dec-2016 Namhyung Kim <namhyung@kernel.org>

perf sched timehist: Add -I/--idle-hist option

The --idle-hist option is to analyze system idle state so which process
makes cpu to go idle. If this option is specified, non-idle events will
be skipped and processes switching to/from idle will be shown.

This option is mostly useful when used with --summary(-only) option. In
the idle-time summary view, idle time is accounted to previous thread
which is run before idle task.

The example output looks like following:

Idle-time summary
comm parent sched-out idle-time min-idle avg-idle max-idle stddev migrations
(count) (msec) (msec) (msec) (msec) %
--------------------------------------------------------------------------------------------
rcu_preempt[7] 2 95 550.872 0.011 5.798 23.146 7.63 0
migration/1[16] 2 1 15.558 15.558 15.558 15.558 0.00 0
khugepaged[39] 2 1 3.062 3.062 3.062 3.062 0.00 0
kworker/0:1H[124] 2 2 4.728 0.611 2.364 4.116 74.12 0
systemd-journal[167] 1 1 4.510 4.510 4.510 4.510 0.00 0
kworker/u16:3[558] 2 13 74.737 0.080 5.749 12.960 21.96 0
irq/34-iwlwifi[628] 2 21 118.403 0.032 5.638 23.990 24.00 0
kworker/u17:0[673] 2 1 3.523 3.523 3.523 3.523 0.00 0
dbus-daemon[722] 1 1 6.743 6.743 6.743 6.743 0.00 0
ifplugd[741] 1 1 58.826 58.826 58.826 58.826 0.00 0
wpa_supplicant[1490] 1 1 13.302 13.302 13.302 13.302 0.00 0
wpa_actiond[1492] 1 2 4.064 0.168 2.032 3.896 91.72 0
dockerd[1500] 1 1 0.055 0.055 0.055 0.055 0.00 0
...

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161208144755.16673-6-namhyung@kernel.org
Link: http://lkml.kernel.org/r/20161213080632.19099-2-namhyung@kernel.org
[ Merged fix sent by Namhyumg, as posted in the second Link: tag ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 853b7407 29-Nov-2016 David Ahern <dsa@cumulusnetworks.com>

perf sched timehist: Add option to specify time window of interest

Add option to allow user to control analysis window. e.g., collect data
for time window and analyze a segment of interest within that window.

Committer notes:

Testing it:

# perf sched record -a usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.593 MB perf.data (25 samples) ]
#
# perf sched timehist | head -18
Samples do not have callchains.
time cpu task name wait time sch delay run time
[tid/pid] (msec) (msec) (msec)
------------- ------ --------------- --------- --------- --------
19818.635579 [0002] <idle> 0.000 0.000 0.000
19818.635613 [0000] perf[9116] 0.000 0.000 0.000
19818.635676 [0000] <idle> 0.000 0.000 0.063
19818.635678 [0000] rcuos/2[29] 0.000 0.002 0.001
19818.635696 [0002] perf[9117] 0.000 0.004 0.116
19818.635702 [0000] <idle> 0.001 0.000 0.024
19818.635709 [0002] migration/2[25] 0.000 0.003 0.012
19818.636263 [0000] usleep[9117] 0.005 0.000 0.560
19818.636316 [0000] <idle> 0.560 0.000 0.053
19818.636358 [0002] <idle> 0.129 0.000 0.649
19818.636358 [0000] usleep[9117] 0.053 0.002 0.042
#

# perf sched timehist --time 19818.635696,
Samples do not have callchains.
time cpu task name wait time sch delay run time
[tid/pid] (msec) (msec) (msec)
------------- ------ --------------- -------- --------- ---------
19818.635696 [0002] perf[9117] 0.000 0.120 0.000
19818.635702 [0000] <idle> 0.019 0.000 0.006
19818.635709 [0002] migration/2[25] 0.000 0.003 0.012
19818.636263 [0000] usleep[9117] 0.005 0.000 0.560
19818.636316 [0000] <idle> 0.560 0.000 0.053
19818.636358 [0002] <idle> 0.129 0.000 0.649
19818.636358 [0000] usleep[9117] 0.053 0.002 0.042
#
# perf sched timehist --time 19818.635696,19818.635709
Samples do not have callchains.
time cpu task name wait time sch delay run time
[tid/pid] (msec) (msec) (msec)
------------- ------ --------------- --------- --------- ---------
19818.635696 [0002] perf[9117] 0.000 0.120 0.000
19818.635702 [0000] <idle> 0.019 0.000 0.006
19818.635709 [0002] migration/2[25] 0.000 0.003 0.012
19818.635709 [0000] usleep[9117] 0.005 0.000 0.006
#

Signed-off-by: David Ahern <dsahern@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1480439746-42695-5-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 350f54fa 25-Nov-2016 David Ahern <dsahern@gmail.com>

perf sched timehist: Handle cpu migration events

Add handlers for sched:sched_migrate_task event. Total number of
migrations is added to summary display and -M/--migrations can be used
to show migration events.

Signed-off-by: David Ahern <dsahern@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1480091321-35591-1-git-send-email-dsa@cumulusnetworks.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# a407b067 15-Nov-2016 David Ahern <dsahern@gmail.com>

perf sched timehist: Add -V/--cpu-visual option

The -V option provides a visual aid for sched switches by cpu:

$ perf sched timehist -V
time cpu 0123456789abc task name b/n time sch delay run time
[tid/pid] (msec) (msec) (msec)
--------------- ------ ------------- -------------------- --------- --------- ---------
...
2412598.429696 [0009] i <idle> 0.000 0.000 0.000
2412598.429767 [0002] s perf[7219] 0.000 0.000 0.000
2412598.429783 [0009] s perf[7220] 0.000 0.006 0.087
2412598.429794 [0010] i <idle> 0.000 0.000 0.000
2412598.429795 [0009] s migration/9[53] 0.000 0.003 0.011
2412598.430370 [0010] s sleep[7220] 0.011 0.000 0.576
2412598.432584 [0003] i <idle> 0.000 0.000 0.000
...

Committer notes:

'i' marks idle time, 's' are scheduler events.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20161116060634.28477-8-namhyung@kernel.org
[ Add documentation based on above commit message ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 6c973c90 15-Nov-2016 David Ahern <dsahern@gmail.com>

perf sched timehist: Add call graph options

If callchains were recorded they are appended to the line with a default stack depth of 5:

1.874569 [0011] gcc[31949] 0.014 0.000 1.148 wait_for_completion_killable <- do_fork <- sys_vfork <- stub_vfork <- __vfork
1.874591 [0010] gcc[31951] 0.000 0.000 0.024 __cond_resched <- _cond_resched <- wait_for_completion <- stop_one_cpu <- sched_exec
1.874603 [0010] migration/10[59] 3.350 0.004 0.011 smpboot_thread_fn <- kthread <- ret_from_fork
1.874604 [0011] <idle> 1.148 0.000 0.035 cpu_startup_entry <- start_secondary
1.874723 [0005] <idle> 0.016 0.000 1.383 cpu_startup_entry <- start_secondary
1.874746 [0005] gcc[31949] 0.153 0.078 0.022 do_wait sys_wait4 <- system_call_fastpath <- __GI___waitpid

--no-call-graph can be used to not show the callchains. --max-stack is used
to control the number of frames shown (default of 5). -x/--excl options can
be used to collapse redundant callchains to get more relevant data on screen.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20161116060634.28477-7-namhyung@kernel.org
[ Add documentation based on above commit message ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# fc1469f1 15-Nov-2016 David Ahern <dsahern@gmail.com>

perf sched timehist: Add -w/--wakeups option

The -w option is to show wakeup events with timehist.

$ perf sched timehist -w
time cpu task name b/n time sch delay run time
[tid/pid] (msec) (msec) (msec)
--------------- ------ -------------------- --------- --------- ---------
2412598.429689 [0002] perf[7219] awakened: perf[7220]
2412598.429696 [0009] <idle> 0.000 0.000 0.000
2412598.429767 [0002] perf[7219] 0.000 0.000 0.000
2412598.429780 [0009] perf[7220] awakened: migration/9[53]
...

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20161116060634.28477-6-namhyung@kernel.org
[ Add documentation based on above commit message ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 49394a2a 15-Nov-2016 David Ahern <dsahern@gmail.com>

perf sched timehist: Introduce timehist command

'perf sched timehist' provides an analysis of scheduling events.

Example usage:
perf sched record -- sleep 1
perf sched timehist

By default it shows the individual schedule events, including the wait
time (time between sched-out and next sched-in events for the task), the
task scheduling delay (time between wakeup and actually running) and run
time for the task:

time cpu task name wait time sch delay run time
[tid/pid] (msec) (msec) (msec)
-------------- ------ -------------------- --------- --------- ---------
79371.874569 [0011] gcc[31949] 0.014 0.000 1.148
79371.874591 [0010] gcc[31951] 0.000 0.000 0.024
79371.874603 [0010] migration/10[59] 3.350 0.004 0.011
79371.874604 [0011] <idle> 1.148 0.000 0.035
79371.874723 [0005] <idle> 0.016 0.000 1.383
79371.874746 [0005] gcc[31949] 0.153 0.078 0.022
...

Times are in msec.usec.

Committer note:

Add above explanation as the 'perf sched timehist' entry for 'man
perf-sched'.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20161116060634.28477-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 73643bb6 12-Apr-2016 Jiri Olsa <jolsa@kernel.org>

perf sched map: Display only given cpus

Introducing --cpus option that will display only given cpus. Could be
used together with color-cpus option.

$ perf sched map --cpus 0,1
*A0 309999.786924 secs A0 => rcu_sched:7
*. 309999.786930 secs
*B0 . 309999.786931 secs B0 => rcuos/2:25
B0 *A0 309999.786947 secs

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1460467771-26532-9-git-send-email-jolsa@kernel.org
[ Added entry to man page ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# cf294f24 12-Apr-2016 Jiri Olsa <jolsa@kernel.org>

perf sched map: Color given cpus

Adding --color-cpus option to display selected cpus with background
color (red by default). It helps on navigating through the perf sched
map output.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1460467771-26532-8-git-send-email-jolsa@kernel.org
[ Added entry to man page ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# a151a37a 12-Apr-2016 Jiri Olsa <jolsa@kernel.org>

perf sched map: Color given pids

Adding --color-pids option to display selected pids in color (blue by
default). It helps on navigating through the 'perf sched map' output.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1460467771-26532-7-git-send-email-jolsa@kernel.org
[ Added entry to man page ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 99623c62 12-Apr-2016 Jiri Olsa <jolsa@kernel.org>

perf sched: Add compact display option

Add compact map display that does not output the whole cpu matrix, only
cpus that got event.

$ perf sched map --compact
*A0 1082427.094098 secs A0 => perf:19404 (CPU 2)
A0 *. 1082427.094127 secs . => swapper:0 (CPU 1)
A0 . *B0 1082427.094174 secs B0 => rcuos/2:25 (CPU 3)
A0 . *. 1082427.094177 secs
*C0 . . 1082427.094187 secs C0 => migration/2:21
C0 *A0 . 1082427.094193 secs
*. A0 . 1082427.094195 secs
*D0 A0 . 1082427.094402 secs D0 => rngd:968
*. A0 . 1082427.094406 secs
. *E0 . 1082427.095221 secs E0 => kworker/1:1:5333
. E0 *F0 1082427.095227 secs F0 => xterm:3342

It helps to display sane output for small thread loads on big cpu
servers.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1460467771-26532-4-git-send-email-jolsa@kernel.org
[ Add entry in 'perf sched' man page ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# efad1415 07-Dec-2011 Robert Richter <robert.richter@amd.com>

perf report: Accept fifos as input file

The default input file for perf report is not handled the same way as
perf record does it for its output file. This leads to unexpected
behavior of perf report, etc. E.g.:

# perf record -a -e cpu-cycles sleep 2 | perf report | cat
failed to open perf.data: No such file or directory (try 'perf record' first)

While perf record writes to a fifo, perf report expects perf.data to be
read. This patch changes this to accept fifos as input file.

Applies to the following commands:

perf annotate
perf buildid-list
perf evlist
perf kmem
perf lock
perf report
perf sched
perf script
perf timechart

Also fixes char const* -> const char* type declaration for filename
strings.

v2:
* Prevent potential null pointer access to input_name in
builtin-report.c. Needed due to removal of patch "perf report: Setup
browser if stdout is a pipe"

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-5-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# e78cb362 27-Sep-2011 Jiri Olsa <jolsa@redhat.com>

perf sched: Fix script command documentation

Fixed leftover from trace -> script rename.

Link: http://lkml.kernel.org/r/1317114995-4534-1-git-send-email-jolsa@redhat.com
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 1eacc94a 30-Nov-2010 Shawn Bohrer <shawn.bohrer@gmail.com>

perf sched: Document missing options

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1291168642-11402-11-git-send-email-shawn.bohrer@gmail.com>
Signed-off-by: Shawn Bohrer <shawn.bohrer@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 854c5548 31-Mar-2010 Randy Dunlap <randy.dunlap@oracle.com>

perf: cleanup some Documentation

Correct typos in perf bench & perf sched help text.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20100331113100.cc898487.randy.dunlap@oracle.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>


# c13f0d3c 13-Sep-2009 Ingo Molnar <mingo@elte.hu>

perf sched: Add 'perf sched trace', improve documentation

Alias 'perf sched trace' to 'perf trace', for workflow completeness.

Add a bit of documentation for perf sched.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


# 0a02ad93 10-Sep-2009 Ingo Molnar <mingo@elte.hu>

perf: Add 'perf sched' tool

This turn-key tool allows scheduler measurements to be
conducted and the results be displayed numerically.

First baby step towards that goal: clone the new command off of
perf trace.

Fix a few other details along the way:

- add (minimal) perf trace documentation

- reorder a few places

- list perf trace in the mainporcelain list as well
as it's a very useful utility.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>