[PATCH v5 6/7] perf util: Report hot streams

[Jin Yao]

We show the streams separately. They are divided into different sections.

1. "Matched hot streams"

2. "Hot streams in old perf data only"

3. "Hot streams in new perf data only".

For each stream, we report the cycles and hot percent (hits%).

For example,

     cycles: 2, hits: 4.08%
 --------------------------
              main div.c:42
      compute_flag div.c:28

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
 v5:
   - Rebase to perf/core

 v4:
   - Remove "Hot chains in old perf data but source line changed
     in new perf data"

 tools/perf/util/callchain.c |  13 ++++
 tools/perf/util/callchain.h |   2 +
 tools/perf/util/stream.c    | 123 ++++++++++++++++++++++++++++++++++++
 tools/perf/util/stream.h    |   3 +
 4 files changed, 141 insertions(+)

diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 90d31582393e..ce66a6308e87 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -1685,3 +1685,16 @@ u64 callchain_total_hits(struct hists *hists)
 
 	return chain_hits;
 }
+
+s64 callchain_avg_cycles(struct callchain_node *cnode)
+{
+	struct callchain_list *chain;
+	s64 cycles = 0;
+
+	list_for_each_entry(chain, &cnode->val, list) {
+		if (chain->srcline && chain->branch_count)
+			cycles += chain->cycles_count / chain->branch_count;
+	}
+
+	return cycles;
+}
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 082f73524c9a..9c099f463723 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -296,4 +296,6 @@ bool callchain_cnode_matched(struct callchain_node *base_cnode,
 
 u64 callchain_total_hits(struct hists *hists);
 
+s64 callchain_avg_cycles(struct callchain_node *cnode);
+
 #endif	/* __PERF_CALLCHAIN_H */
diff --git a/tools/perf/util/stream.c b/tools/perf/util/stream.c
index 642316078e40..2d3dc7361ef1 100644
--- a/tools/perf/util/stream.c
+++ b/tools/perf/util/stream.c
@@ -199,3 +199,126 @@ void match_evsel_streams(struct evsel_streams *es_base,
 			stream_link(base_stream, pair_stream);
 	}
 }
+
+static void print_callchain_pair(struct stream *base_stream, int idx,
+				 struct evsel_streams *es_base,
+				 struct evsel_streams *es_pair)
+{
+	struct callchain_node *base_cnode = base_stream->cnode;
+	struct callchain_node *pair_cnode = base_stream->pair_cnode;
+	struct callchain_list *base_chain, *pair_chain;
+	char buf1[512], buf2[512], cbuf1[256], cbuf2[256];
+	char *s1, *s2;
+	double pct;
+
+	printf("\nhot chain pair %d:\n", idx);
+
+	pct = (double)base_cnode->hit / (double)es_base->streams_hits;
+	scnprintf(buf1, sizeof(buf1), "cycles: %ld, hits: %.2f%%",
+		  callchain_avg_cycles(base_cnode), pct * 100.0);
+
+	pct = (double)pair_cnode->hit / (double)es_pair->streams_hits;
+	scnprintf(buf2, sizeof(buf2), "cycles: %ld, hits: %.2f%%",
+		  callchain_avg_cycles(pair_cnode), pct * 100.0);
+
+	printf("%35s\t%35s\n", buf1, buf2);
+
+	printf("%35s\t%35s\n",
+	       "---------------------------",
+	       "--------------------------");
+
+	pair_chain = list_first_entry(&pair_cnode->val,
+				      struct callchain_list,
+				      list);
+
+	list_for_each_entry(base_chain, &base_cnode->val, list) {
+		if (&pair_chain->list == &pair_cnode->val)
+			return;
+
+		s1 = callchain_list__sym_name(base_chain, cbuf1, sizeof(cbuf1),
+					      false);
+		s2 = callchain_list__sym_name(pair_chain, cbuf2, sizeof(cbuf2),
+					      false);
+
+		scnprintf(buf1, sizeof(buf1), "%35s\t%35s", s1, s2);
+		printf("%s\n", buf1);
+		pair_chain = list_next_entry(pair_chain, list);
+	}
+}
+
+static void print_stream_callchain(struct stream *stream, int idx,
+				   struct evsel_streams *es, bool pair)
+{
+	struct callchain_node *cnode = stream->cnode;
+	struct callchain_list *chain;
+	char buf[512], cbuf[256], *s;
+	double pct;
+
+	printf("\nhot chain %d:\n", idx);
+
+	pct = (double)cnode->hit / (double)es->streams_hits;
+	scnprintf(buf, sizeof(buf), "cycles: %ld, hits: %.2f%%",
+		  callchain_avg_cycles(cnode), pct * 100.0);
+
+	if (pair) {
+		printf("%35s\t%35s\n", "", buf);
+		printf("%35s\t%35s\n",
+		       "", "--------------------------");
+	} else {
+		printf("%35s\n", buf);
+		printf("%35s\n", "--------------------------");
+	}
+
+	list_for_each_entry(chain, &cnode->val, list) {
+		s = callchain_list__sym_name(chain, cbuf, sizeof(cbuf), false);
+
+		if (pair)
+			scnprintf(buf, sizeof(buf), "%35s\t%35s", "", s);
+		else
+			scnprintf(buf, sizeof(buf), "%35s", s);
+
+		printf("%s\n", buf);
+	}
+}
+
+static void callchain_streams_report(struct evsel_streams *es_base,
+				     struct evsel_streams *es_pair)
+{
+	struct stream *base_stream;
+	int i, idx = 0;
+
+	printf("[ Matched hot streams ]\n");
+	for (i = 0; i < es_base->nr_streams; i++) {
+		base_stream = &es_base->streams[i];
+		if (base_stream->pair_cnode) {
+			print_callchain_pair(base_stream, ++idx,
+					     es_base, es_pair);
+		}
+	}
+
+	idx = 0;
+	printf("\n[ Hot streams in old perf data only ]\n");
+	for (i = 0; i < es_base->nr_streams; i++) {
+		base_stream = &es_base->streams[i];
+		if (!base_stream->pair_cnode) {
+			print_stream_callchain(base_stream, ++idx,
+					       es_base, false);
+		}
+	}
+
+	idx = 0;
+	printf("\n[ Hot streams in new perf data only ]\n");
+	for (i = 0; i < es_pair->nr_streams; i++) {
+		base_stream = &es_pair->streams[i];
+		if (!base_stream->pair_cnode) {
+			print_stream_callchain(base_stream, ++idx,
+					       es_pair, true);
+		}
+	}
+}
+
+void evsel_streams_report(struct evsel_streams *es_base,
+			  struct evsel_streams *es_pair)
+{
+	return callchain_streams_report(es_base, es_pair);
+}
diff --git a/tools/perf/util/stream.h b/tools/perf/util/stream.h
index 56dfa90c810d..33b02c059d23 100644
--- a/tools/perf/util/stream.h
+++ b/tools/perf/util/stream.h
@@ -28,4 +28,7 @@ struct evsel_streams *evsel_streams_get(struct evsel_streams *es,
 void match_evsel_streams(struct evsel_streams *es_base,
 			 struct evsel_streams *es_pair);
 
+void evsel_streams_report(struct evsel_streams *es_base,
+			  struct evsel_streams *es_pair);
+
 #endif /* __PERF_STREAM_H */
-- 
2.17.1