[PATCH 36/48] perf tools: Add perf_mmap__read_tail function

[Jiri Olsa]

It will be used in following patches.

Link: http://lkml.kernel.org/n/tip-4id1fjlu5ypfqnu9kvpo7l3z@xxxxxxxxxxxxxx
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
 tools/perf/util/mmap.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h
index bad05b12b9df..eb39d3f85b93 100644
--- a/tools/perf/util/mmap.h
+++ b/tools/perf/util/mmap.h
@@ -79,6 +79,13 @@ static inline u64 perf_mmap__read_head(struct perf_mmap *mm)
 	return head;
 }
 
+static inline u64 perf_mmap__read_tail(struct perf_mmap *md)
+{
+	struct perf_event_mmap_page *pc = md->base;
+
+	return pc->data_tail;
+}
+
 static inline void perf_mmap__write_tail(struct perf_mmap *md, u64 tail)
 {
 	struct perf_event_mmap_page *pc = md->base;
-- 
2.17.1