[PATCH v3 5/7] perf util: Calculate the sum of all streams hits

[Jin Yao]

We have used callchain_node->hit to measure the hot level of one
stream. This patch calculates the sum of hits of all streams.

Then in next patch, we can use following formula to report hot
percent for one stream.

hot percent = callchain_node->hit / sum of all hits

 v2:
 ---
 Combine the variable decl line with its initial assignment
 in total_callchain_hits().

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
 tools/perf/util/callchain.c | 34 ++++++++++++++++++++++++++++++++++
 tools/perf/util/callchain.h |  1 +
 2 files changed, 35 insertions(+)

diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index 1619f7fa4076..b0c8757c2dcf 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -1683,6 +1683,38 @@ static void update_hot_streams(struct hist_entry *he,
 	}
 }
 
+static u64 count_callchain_hits(struct hist_entry *he)
+{
+	struct rb_root *root = &he->sorted_chain;
+	struct rb_node *rb_node = rb_first(root);
+	struct callchain_node *node;
+	u64 chain_hits = 0;
+
+	while (rb_node) {
+		node = rb_entry(rb_node, struct callchain_node, rb_node);
+		chain_hits += node->hit;
+		rb_node = rb_next(rb_node);
+	}
+
+	return chain_hits;
+}
+
+static u64 total_callchain_hits(struct hists *hists)
+{
+	struct rb_node *next = rb_first_cached(&hists->entries);
+	u64 chain_hits = 0;
+
+	while (next) {
+		struct hist_entry *he = rb_entry(next, struct hist_entry,
+						 rb_node);
+
+		chain_hits += count_callchain_hits(he);
+		next = rb_next(&he->rb_node);
+	}
+
+	return chain_hits;
+}
+
 static void get_hot_streams(struct hists *hists,
 			    struct callchain_streams *s)
 {
@@ -1695,6 +1727,8 @@ static void get_hot_streams(struct hists *hists,
 		update_hot_streams(he, s);
 		next = rb_next(&he->rb_node);
 	}
+
+	s->chain_hits = total_callchain_hits(hists);
 }
 
 struct callchain_streams *callchain_evsel_streams_create(struct evlist *evlist,
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 52aa01b9eedf..a9b20b785dc7 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -181,6 +181,7 @@ struct callchain_streams {
 	int			nr_streams_max;
 	int			nr_streams;
 	int			evsel_idx;
+	u64			chain_hits;
 };
 
 extern __thread struct callchain_cursor callchain_cursor;
-- 
2.17.1