[PATCH v7 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>
---
 v7:
   - Rename functions with 'evsel_streams__' prefix

 v6:
   - Rebase to perf/core

 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 4f824bfcc072..1b60985690bb 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -1699,3 +1699,16 @@ 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 ac5bea9c1eb7..5824134f983b 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -305,4 +305,6 @@ 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 47c5956b3378..4bd5e5a00aa5 100644
--- a/tools/perf/util/stream.c
+++ b/tools/perf/util/stream.c
@@ -217,3 +217,126 @@ void evsel_streams__match(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 a61072eda64d..bee768874fea 100644
--- a/tools/perf/util/stream.h
+++ b/tools/perf/util/stream.h
@@ -35,4 +35,7 @@ struct evsel_streams *evsel_streams__entry(struct evlist_streams *els,
 void evsel_streams__match(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