tree b72c9902243849c740a931aceed11c95b1b51d45
parent 9e6a8022f93e62a3d372a5aba640f98a36681b6e
author Yabin Cui <yabinc@google.com> 1483743702 -0800
committer Yabin Cui <yabinc@google.com> 1483744520 -0800

simpleperf: fix synchronization when reading mapped buffer.

Fixed according to http://lxr.free-electrons.com/source/kernel/events/ring_buffer.c#L61.

Test: run simpleperf_unit_test.

Change-Id: I44486b1630c92de57fb575b502b2d7c798e46e4b