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perf stat: Display user and system time

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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 <mingo@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180605121313.31337-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Jiri Olsa 2018-06-05 14:13:13 +02:00 committed by Arnaldo Carvalho de Melo
parent f92da71280
commit 0ce2da1483
2 changed files with 56 additions and 12 deletions
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40
tools/perf/Documentation/perf-stat.txt
View File

@ -310,20 +310,38 @@ Users who wants to get the actual value can apply --no-metric-only.
EXAMPLES
--------
$ perf stat -- make -j
$ perf stat -- make
Performance counter stats for 'make -j':
Performance counter stats for 'make':
8117.370256 task clock ticks # 11.281 CPU utilization factor
678 context switches # 0.000 M/sec
133 CPU migrations # 0.000 M/sec
235724 pagefaults # 0.029 M/sec
24821162526 CPU cycles # 3057.784 M/sec
18687303457 instructions # 2302.138 M/sec
172158895 cache references # 21.209 M/sec
27075259 cache misses # 3.335 M/sec
83723.452481 task-clock:u (msec) # 1.004 CPUs utilized
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
3,228,188 page-faults:u # 0.039 M/sec
229,570,665,834 cycles:u # 2.742 GHz
313,163,853,778 instructions:u # 1.36 insn per cycle
69,704,684,856 branches:u # 832.559 M/sec
2,078,861,393 branch-misses:u # 2.98% of all branches
Wall-clock time elapsed: 719.554352 msecs
83.409183620 seconds time elapsed
74.684747000 seconds user
8.739217000 seconds sys
TIMINGS
-------
As displayed in the example above we can display 3 types of timings.
We always display the time the counters were enabled/alive:
83.409183620 seconds time elapsed
For workload sessions we also display time the workloads spent in
user/system lands:
74.684747000 seconds user
8.739217000 seconds sys
Those times are the very same as displayed by the 'time' tool.
CSV FORMAT
----------

28
tools/perf/builtin-stat.c
View File

@ -80,6 +80,9 @@
#include <sys/stat.h>
#include <sys/wait.h>
#include <unistd.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/wait.h>
#include "sane_ctype.h"
@ -175,6 +178,8 @@ static int output_fd;
static int print_free_counters_hint;
static int print_mixed_hw_group_error;
static u64 *walltime_run;
static bool ru_display = false;
static struct rusage ru_data;
struct perf_stat {
bool record;
@ -726,7 +731,7 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx)
break;
}
}
waitpid(child_pid, &status, 0);
wait4(child_pid, &status, 0, &ru_data);
if (workload_exec_errno) {
const char *emsg = str_error_r(workload_exec_errno, msg, sizeof(msg));
@ -1804,6 +1809,11 @@ static void print_table(FILE *output, int precision, double avg)
fprintf(output, "\n%*s# Final result:\n", indent, "");
}
static double timeval2double(struct timeval *t)
{
return t->tv_sec + (double) t->tv_usec/USEC_PER_SEC;
}
static void print_footer(void)
{
double avg = avg_stats(&walltime_nsecs_stats) / NSEC_PER_SEC;
@ -1815,6 +1825,15 @@ static void print_footer(void)
if (run_count == 1) {
fprintf(output, " %17.9f seconds time elapsed", avg);
if (ru_display) {
double ru_utime = timeval2double(&ru_data.ru_utime);
double ru_stime = timeval2double(&ru_data.ru_stime);
fprintf(output, "\n\n");
fprintf(output, " %17.9f seconds user\n", ru_utime);
fprintf(output, " %17.9f seconds sys\n", ru_stime);
}
} else {
double sd = stddev_stats(&walltime_nsecs_stats) / NSEC_PER_SEC;
/*
@ -2950,6 +2969,13 @@ int cmd_stat(int argc, const char **argv)
setup_system_wide(argc);
/*
* Display user/system times only for single
* run and when there's specified tracee.
*/
if ((run_count == 1) && target__none(&target))
ru_display = true;
if (run_count < 0) {
pr_err("Run count must be a positive number\n");
parse_options_usage(stat_usage, stat_options, "r", 1);