perf sched timehist: Show total scheduling time

Show length of analyzed sample time and rate of idle task running.
This also takes care of time range given by --time option.

  $ perf sched timehist -sI | tail
  Samples do not have callchains.
  Idle stats:
      CPU  0 idle for    930.316  msec  ( 92.93%)
      CPU  1 idle for    963.614  msec  ( 96.25%)
      CPU  2 idle for    885.482  msec  ( 88.45%)
      CPU  3 idle for    938.635  msec  ( 93.76%)

      Total number of unique tasks: 118
  Total number of context switches: 2337
             Total run time (msec): 3718.048
      Total scheduling time (msec): 1001.131  (x 4)

Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20161222060350.17655-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index d53e706a6f1706d2d69caa93132521f55d89d072..5b134b0d1ff37e42a1b82b5973528c4003bb80f3 100644 (file)
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -209,6 +209,7 @@ struct perf_sched {
        u64             skipped_samples;
        const char      *time_str;
        struct perf_time_interval ptime;
+       struct perf_time_interval hist_time;
 };
 
 /* per thread run time data */
@@ -2460,6 +2461,11 @@ static int timehist_sched_change_event(struct perf_tool *tool,
                timehist_print_sample(sched, sample, &al, thread, t);
 
 out:
+       if (sched->hist_time.start == 0 && t >= ptime->start)
+               sched->hist_time.start = t;
+       if (ptime->end == 0 || t <= ptime->end)
+               sched->hist_time.end = t;
+
        if (tr) {
                /* time of this sched_switch event becomes last time task seen */
                tr->last_time = sample->time;
@@ -2624,6 +2630,7 @@ static void timehist_print_summary(struct perf_sched *sched,
        struct thread *t;
        struct thread_runtime *r;
        int i;
+       u64 hist_time = sched->hist_time.end - sched->hist_time.start;
 
        memset(&totals, 0, sizeof(totals));
 
@@ -2665,7 +2672,7 @@ static void timehist_print_summary(struct perf_sched *sched,
                        totals.sched_count += r->run_stats.n;
                        printf("    CPU %2d idle for ", i);
                        print_sched_time(r->total_run_time, 6);
-                       printf(" msec\n");
+                       printf(" msec  (%6.2f%%)\n", 100.0 * r->total_run_time / hist_time);
                } else
                        printf("    CPU %2d idle entire time window\n", i);
        }
@@ -2701,12 +2708,16 @@ static void timehist_print_summary(struct perf_sched *sched,
 
        printf("\n"
               "    Total number of unique tasks: %" PRIu64 "\n"
-              "Total number of context switches: %" PRIu64 "\n"
-              "           Total run time (msec): ",
+              "Total number of context switches: %" PRIu64 "\n",
               totals.task_count, totals.sched_count);
 
+       printf("           Total run time (msec): ");
        print_sched_time(totals.total_run_time, 2);
        printf("\n");
+
+       printf("    Total scheduling time (msec): ");
+       print_sched_time(hist_time, 2);
+       printf(" (x %d)\n", sched->max_cpu);
 }
 
 typedef int (*sched_handler)(struct perf_tool *tool,