[tip:perf/core] perf sched timehist: Add -V/--cpu-visual option

From: tip-bot for David Ahern
Date: Wed Nov 23 2016 - 23:43:43 EST


Commit-ID: a407b0678bc1c39d70af5fdbe6421c164b69a8c0
Gitweb: http://git.kernel.org/tip/a407b0678bc1c39d70af5fdbe6421c164b69a8c0
Author: David Ahern <dsahern@xxxxxxxxx>
AuthorDate: Wed, 16 Nov 2016 15:06:33 +0900
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Wed, 23 Nov 2016 10:44:09 -0300

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@xxxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Acked-by: Ingo Molnar <mingo@xxxxxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Andi Kleen <andi@xxxxxxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20161116060634.28477-8-namhyung@xxxxxxxxxx
[ Add documentation based on above commit message ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/Documentation/perf-sched.txt | 5 ++++
tools/perf/builtin-sched.c | 44 +++++++++++++++++++++++++++++++--
2 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/tools/perf/Documentation/perf-sched.txt b/tools/perf/Documentation/perf-sched.txt
index 8345208..fb9e52d 100644
--- a/tools/perf/Documentation/perf-sched.txt
+++ b/tools/perf/Documentation/perf-sched.txt
@@ -119,6 +119,11 @@ OPTIONS for 'perf sched timehist'
--symfs=<directory>::
Look for files with symbols relative to this directory.

+-V::
+--cpu-visual::
+ Show visual aid for sched switches by CPU: 'i' marks idle time,
+ 's' are scheduler events.
+
-w::
--wakeups::
Show wakeup events.
diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index 1f87316..829468d 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -201,6 +201,7 @@ struct perf_sched {
bool summary_only;
bool show_callchain;
unsigned int max_stack;
+ bool show_cpu_visual;
bool show_wakeups;
u64 skipped_samples;
};
@@ -1783,10 +1784,23 @@ static char *timehist_get_commstr(struct thread *thread)
return str;
}

-static void timehist_header(void)
+static void timehist_header(struct perf_sched *sched)
{
+ u32 ncpus = sched->max_cpu + 1;
+ u32 i, j;
+
printf("%15s %6s ", "time", "cpu");

+ if (sched->show_cpu_visual) {
+ printf(" ");
+ for (i = 0, j = 0; i < ncpus; ++i) {
+ printf("%x", j++);
+ if (j > 15)
+ j = 0;
+ }
+ printf(" ");
+ }
+
printf(" %-20s %9s %9s %9s",
"task name", "wait time", "sch delay", "run time");

@@ -1797,6 +1811,9 @@ static void timehist_header(void)
*/
printf("%15s %-6s ", "", "");

+ if (sched->show_cpu_visual)
+ printf(" %*s ", ncpus, "");
+
printf(" %-20s %9s %9s %9s\n", "[tid/pid]", "(msec)", "(msec)", "(msec)");

/*
@@ -1804,6 +1821,9 @@ static void timehist_header(void)
*/
printf("%.15s %.6s ", graph_dotted_line, graph_dotted_line);

+ if (sched->show_cpu_visual)
+ printf(" %.*s ", ncpus, graph_dotted_line);
+
printf(" %.20s %.9s %.9s %.9s",
graph_dotted_line, graph_dotted_line, graph_dotted_line,
graph_dotted_line);
@@ -1817,11 +1837,28 @@ static void timehist_print_sample(struct perf_sched *sched,
struct thread *thread)
{
struct thread_runtime *tr = thread__priv(thread);
+ u32 max_cpus = sched->max_cpu + 1;
char tstr[64];

timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
printf("%15s [%04d] ", tstr, sample->cpu);

+ if (sched->show_cpu_visual) {
+ u32 i;
+ char c;
+
+ printf(" ");
+ for (i = 0; i < max_cpus; ++i) {
+ /* flag idle times with 'i'; others are sched events */
+ if (i == sample->cpu)
+ c = (thread->tid == 0) ? 'i' : 's';
+ else
+ c = ' ';
+ printf("%c", c);
+ }
+ printf(" ");
+ }
+
printf(" %-*s ", comm_width, timehist_get_commstr(thread));

print_sched_time(tr->dt_wait, 6);
@@ -2095,6 +2132,8 @@ static void timehist_print_wakeup_event(struct perf_sched *sched,

timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
printf("%15s [%04d] ", tstr, sample->cpu);
+ if (sched->show_cpu_visual)
+ printf(" %*s ", sched->max_cpu + 1, "");

printf(" %-*s ", comm_width, timehist_get_commstr(thread));

@@ -2458,7 +2497,7 @@ static int perf_sched__timehist(struct perf_sched *sched)
sched->summary = sched->summary_only;

if (!sched->summary_only)
- timehist_header();
+ timehist_header(sched);

err = perf_session__process_events(session);
if (err) {
@@ -2842,6 +2881,7 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
OPT_BOOLEAN('S', "with-summary", &sched.summary,
"Show all syscalls and summary with statistics"),
OPT_BOOLEAN('w', "wakeups", &sched.show_wakeups, "Show wakeup events"),
+ OPT_BOOLEAN('V', "cpu-visual", &sched.show_cpu_visual, "Add CPU visual"),
OPT_PARENT(sched_options)
};