perf hist: Clarify events_stats fields usage

The events_stats.total field is too generic, rename it to .total_period,
and also add a comment explaining that it is the sum of all the .period
fields in samples, that is needed because we use auto-freq to avoid
sampling artifacts.

Ditto for events_stats.lost, that is the sum of all lost_event.lost
fields, i.e. the number of events the kernel dropped.

Looking at the users, builtin-sched.c can make use of these fields and
stop doing it again.

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

1 files changed, 4 insertions, 4 deletions

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index f13cda1ef059..b8f47ded6287 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -138,14 +138,14 @@ static int add_event_total(struct perf_session *session,
         if (!hists)
                 return -ENOMEM;
 
-        hists->stats.total += data->period;
+        hists->stats.total_period += data->period;
         /*
          * FIXME: add_event_total should be moved from here to
          * perf_session__process_event so that the proper hist is passed to
          * the event_op methods.
          */
         hists__inc_nr_events(hists, PERF_RECORD_SAMPLE);
-        session->hists.stats.total += data->period;
+        session->hists.stats.total_period += data->period;
         return 0;
 }
 
@@ -322,10 +322,10 @@ static int __cmd_report(void)
                         if (rb_first(&session->hists.entries) ==
                             rb_last(&session->hists.entries))
                                 fprintf(stdout, "# Samples: %Ld\n#\n",
-                                        hists->stats.total);
+                                        hists->stats.total_period);
                         else
                                 fprintf(stdout, "# Samples: %Ld %s\n#\n",
-                                        hists->stats.total,
+                                        hists->stats.total_period,
                                         __event_name(hists->type, hists->config));
 
                         hists__fprintf(hists, NULL, false, stdout);