perf evsel: Add PERF_SAMPLE_READ sample related processing

For sample with sample type PERF_SAMPLE_READ the period value is stored
in the 'struct sample_read'.

Moreover if the read format has PERF_FORMAT_GROUP, the 'struct
sample_read' contains period values for all events in the group (for
which the sample's event is a leader).

We deliver separated samples for all the values contained within the
'struct sample_read'.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-6mdm5xkrm6kypouh1c33cyys@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 74 insertions, 1 deletions

diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 3f156ccc1acb..6a2cf261f38e 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -38,6 +38,9 @@ struct perf_sample_id {
         struct hlist_node       node;
         u64                     id;
         struct perf_evsel       *evsel;
+
+        /* Holds total ID period value for PERF_SAMPLE_READ processing. */
+        u64                     period;
 };
 
 /** struct perf_evsel - event selector
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index f082921a062d..9247d9c2f5e3 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -860,6 +860,75 @@ static struct machine *
         return &session->machines.host;
 }
 
+static int deliver_sample_value(struct perf_session *session,
+                                struct perf_tool *tool,
+                                union perf_event *event,
+                                struct perf_sample *sample,
+                                struct sample_read_value *v,
+                                struct machine *machine)
+{
+        struct perf_sample_id *sid;
+
+        sid = perf_evlist__id2sid(session->evlist, v->id);
+        if (sid) {
+                sample->id     = v->id;
+                sample->period = v->value - sid->period;
+                sid->period    = v->value;
+        }
+
+        if (!sid || sid->evsel == NULL) {
+                ++session->stats.nr_unknown_id;
+                return 0;
+        }
+
+        return tool->sample(tool, event, sample, sid->evsel, machine);
+}
+
+static int deliver_sample_group(struct perf_session *session,
+                                struct perf_tool *tool,
+                                union  perf_event *event,
+                                struct perf_sample *sample,
+                                struct machine *machine)
+{
+        int ret = -EINVAL;
+        u64 i;
+
+        for (i = 0; i < sample->read.group.nr; i++) {
+                ret = deliver_sample_value(session, tool, event, sample,
+                                           &sample->read.group.values[i],
+                                           machine);
+                if (ret)
+                        break;
+        }
+
+        return ret;
+}
+
+static int
+perf_session__deliver_sample(struct perf_session *session,
+                             struct perf_tool *tool,
+                             union  perf_event *event,
+                             struct perf_sample *sample,
+                             struct perf_evsel *evsel,
+                             struct machine *machine)
+{
+        /* We know evsel != NULL. */
+        u64 sample_type = evsel->attr.sample_type;
+        u64 read_format = evsel->attr.read_format;
+
+        /* Standard sample delievery. */
+        if (!(sample_type & PERF_SAMPLE_READ))
+                return tool->sample(tool, event, sample, evsel, machine);
+
+        /* For PERF_SAMPLE_READ we have either single or group mode. */
+        if (read_format & PERF_FORMAT_GROUP)
+                return deliver_sample_group(session, tool, event, sample,
+                                            machine);
+        else
+                return deliver_sample_value(session, tool, event, sample,
+                                            &sample->read.one, machine);
+}
+
 static int perf_session_deliver_event(struct perf_session *session,
                                       union perf_event *event,
                                       struct perf_sample *sample,
@@ -902,7 +971,8 @@ static int perf_session_deliver_event(struct perf_session *session,
                         ++session->stats.nr_unprocessable_samples;
                         return 0;
                 }
-                return tool->sample(tool, event, sample, evsel, machine);
+                return perf_session__deliver_sample(session, tool, event,
+                                                    sample, evsel, machine);
         case PERF_RECORD_MMAP:
                 return tool->mmap(tool, event, sample, machine);
         case PERF_RECORD_COMM: