[PATCH 47/79] libperf: Add perf_evlist__for_each_evsel macro

[Jiri Olsa]

Adding perf_evlist__for_each_evsel macro to iterate
perf_evsel objects in evlist.

Adding perf_evlist__next function to do that.

Link: http://lkml.kernel.org/n/tip-usi0zxyxmai1ld94nrbum43i@xxxxxxxxxxxxxx
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
 tools/perf/lib/evlist.c              | 20 ++++++++++++++++++++
 tools/perf/lib/include/perf/evlist.h |  7 +++++++
 tools/perf/lib/libperf.map           |  1 +
 3 files changed, 28 insertions(+)

diff --git a/tools/perf/lib/evlist.c b/tools/perf/lib/evlist.c
index 0517deb4cb1c..8c26ebf290f0 100644
--- a/tools/perf/lib/evlist.c
+++ b/tools/perf/lib/evlist.c
@@ -34,3 +34,23 @@ struct perf_evlist *perf_evlist__new(void)
 
 	return evlist;
 }
+
+struct perf_evsel*
+perf_evlist__next(struct perf_evlist *evlist, struct perf_evsel *prev)
+{
+	struct perf_evsel *next;
+
+	if (!prev) {
+		next = list_first_entry(&evlist->entries,
+					struct perf_evsel,
+					node);
+	} else {
+		next = list_next_entry(prev, node);
+	}
+
+	/* Empty list is noticed here so don't need checking on entry. */
+	if (&next->node == &evlist->entries)
+		return NULL;
+
+	return next;
+}
diff --git a/tools/perf/lib/include/perf/evlist.h b/tools/perf/lib/include/perf/evlist.h
index 7255a60869a1..5092b622935b 100644
--- a/tools/perf/lib/include/perf/evlist.h
+++ b/tools/perf/lib/include/perf/evlist.h
@@ -13,5 +13,12 @@ LIBPERF_API void perf_evlist__add(struct perf_evlist *evlist,
 LIBPERF_API void perf_evlist__remove(struct perf_evlist *evlist,
 				     struct perf_evsel *evsel);
 LIBPERF_API struct perf_evlist *perf_evlist__new(void);
+LIBPERF_API struct perf_evsel* perf_evlist__next(struct perf_evlist *evlist,
+						 struct perf_evsel *evsel);
+
+#define perf_evlist__for_each_evsel(evlist, pos)	\
+	for ((pos) = perf_evlist__next((evlist), NULL);	\
+	     (pos) != NULL;				\
+	     (pos) = perf_evlist__next((evlist), (pos)))
 
 #endif /* __LIBPERF_EVLIST_H */
diff --git a/tools/perf/lib/libperf.map b/tools/perf/lib/libperf.map
index e3eac9b60726..c0968226f7b6 100644
--- a/tools/perf/lib/libperf.map
+++ b/tools/perf/lib/libperf.map
@@ -17,6 +17,7 @@ LIBPERF_0.0.1 {
 		perf_evlist__init;
 		perf_evlist__add;
 		perf_evlist__remove;
+		perf_evlist__next;
 	local:
 		*;
 };
-- 
2.21.0