[PATCH v7 4/7] perf util: Link stream pair

From: Jin Yao
Date: Sun Sep 20 2020 - 23:34:42 EST


In previous patch, we have created an evsel_streams for one event,
and top N hottest streams will be saved in a stream array in
evsel_streams.

This patch compares total streams among two evsel_streams.

Once two streams are fully matched, they will be linked as
a pair. From the pair, we can know which streams are matched.

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
v7:
- Rename functions with 'stream__' prefix.

v6:
- Rebase to perf/core

v5:
- Remove enum stream_type

v4:
- New patch in v4.

tools/perf/util/stream.c | 40 ++++++++++++++++++++++++++++++++++++++++
tools/perf/util/stream.h | 4 ++++
2 files changed, 44 insertions(+)

diff --git a/tools/perf/util/stream.c b/tools/perf/util/stream.c
index e1c7d6c6126b..0d6a7452320a 100644
--- a/tools/perf/util/stream.c
+++ b/tools/perf/util/stream.c
@@ -175,3 +175,43 @@ struct evsel_streams *evsel_streams__entry(struct evlist_streams *els,

return NULL;
}
+
+static struct stream *stream__callchain_match(struct stream *base_stream,
+ struct evsel_streams *es_pair)
+{
+ for (int i = 0; i < es_pair->nr_streams; i++) {
+ struct stream *pair_stream = &es_pair->streams[i];
+
+ if (callchain_cnode_matched(base_stream->cnode,
+ pair_stream->cnode)) {
+ return pair_stream;
+ }
+ }
+
+ return NULL;
+}
+
+static struct stream *stream__match(struct stream *base_stream,
+ struct evsel_streams *es_pair)
+{
+ return stream__callchain_match(base_stream, es_pair);
+}
+
+static void stream__link(struct stream *base_stream, struct stream *pair_stream)
+{
+ base_stream->pair_cnode = pair_stream->cnode;
+ pair_stream->pair_cnode = base_stream->cnode;
+}
+
+void evsel_streams__match(struct evsel_streams *es_base,
+ struct evsel_streams *es_pair)
+{
+ for (int i = 0; i < es_base->nr_streams; i++) {
+ struct stream *base_stream = &es_base->streams[i];
+ struct stream *pair_stream;
+
+ pair_stream = stream__match(base_stream, es_pair);
+ if (pair_stream)
+ stream__link(base_stream, pair_stream);
+ }
+}
diff --git a/tools/perf/util/stream.h b/tools/perf/util/stream.h
index f01335677479..cb131f41f5b1 100644
--- a/tools/perf/util/stream.h
+++ b/tools/perf/util/stream.h
@@ -6,6 +6,7 @@

struct stream {
struct callchain_node *cnode;
+ struct callchain_node *pair_cnode;
};

struct evsel_streams {
@@ -30,4 +31,7 @@ struct evlist_streams *evlist__create_streams(struct evlist *evlist,
struct evsel_streams *evsel_streams__entry(struct evlist_streams *els,
int evsel_idx);

+void evsel_streams__match(struct evsel_streams *es_base,
+ struct evsel_streams *es_pair);
+
#endif /* __PERF_STREAM_H */
--
2.17.1