AudioTrack: fix unwanted underrun when restarting

When restarting an AudioTrack from stopped state, it is necessary
to force refresh of mRemainingFrames by processAudioBuffer() as
the last write before stop() could be partial. No doing so will lead
into unnecessary sleep before filling the non contiguous part
of the buffer returned by obtainBuffer() when processAudioBuffer()
is executed for the first time after start().

Change-Id: Id703f8dc092a6f07c905eee194054b4a978f979d

1 files changed, 3 insertions, 0 deletions

diff --git a/media/libmedia/AudioTrack.cpp b/media/libmedia/AudioTrack.cpp
index dd0ec73..214e789 100644
--- a/media/libmedia/AudioTrack.cpp
+++ b/media/libmedia/AudioTrack.cpp
@@ -387,6 +387,9 @@ status_t AudioTrack::start()
     if (previousState == STATE_STOPPED || previousState == STATE_FLUSHED) {
         // reset current position as seen by client to 0
         mProxy->setEpoch(mProxy->getEpoch() - mProxy->getPosition());
+        // force refresh of remaining frames by processAudioBuffer() as last
+        // write before stop could be partial.
+        mRefreshRemaining = true;
     }
     mNewPosition = mProxy->getPosition() + mUpdatePeriod;
     int32_t flags = android_atomic_and(~CBLK_DISABLED, &mCblk->mFlags);