perf report: Add an indication of what time slices are used

Add a time slices indication to the perf report header.

For example,

  # perf report --stdio --time 10%

  # Total Lost Samples: 0
  #
  # Samples: 9K of event 'cycles:ppp' (time slices: 10%)
  # Event count (approx.): 8951288803

Signed-off-by: Jin Yao <[email protected]>
Suggested--by: Arnaldo Carvalho de Melo <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Reviewed-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 7d4f0a5de326156cae7ba4511120a6c884dc9715..4aaaa37262a8eac07ede7980a6ad7c9434f84ac4 100644 (file)
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -404,6 +404,9 @@ static size_t hists__fprintf_nr_sample_events(struct hists *hists, struct report
        if (evname != NULL)
                ret += fprintf(fp, " of event '%s'", evname);
 
+       if (rep->time_str)
+               ret += fprintf(fp, " (time slices: %s)", rep->time_str);
+
        if (symbol_conf.show_ref_callgraph &&
            strstr(evname, "call-graph=no")) {
                ret += fprintf(fp, ", show reference callgraph");