From 54464ba861aaafd11ee5645f5d1ecd1171c6e9fe Mon Sep 17 00:00:00 2001 From: Glenn Kasten Date: Sun, 28 Sep 2014 14:41:07 -0700 Subject: Fix uncertainty of one normal mix buffer in AudioTrack::getTimestamp The per-thread timestamp latch was not synchronized with the per-track released frames. Now the value of each track's released frames is latched along with the timestamp. Bug: 17531839 Bug: 17669342 Change-Id: I96252782911bd42a2534cc4030521b7eeb99a7b9 --- services/audioflinger/Threads.cpp | 13 +++++++++++++ services/audioflinger/Threads.h | 1 + services/audioflinger/Tracks.cpp | 10 +++++++++- 3 files changed, 23 insertions(+), 1 deletion(-) (limited to 'services') diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp index 818bb05..fe258ae 100644 --- a/services/audioflinger/Threads.cpp +++ b/services/audioflinger/Threads.cpp @@ -2126,6 +2126,7 @@ ssize_t AudioFlinger::PlaybackThread::threadLoop_write() size_t totalFramesWritten = mNormalSink->framesWritten(); if (totalFramesWritten >= mLatchD.mTimestamp.mPosition) { mLatchD.mUnpresentedFrames = totalFramesWritten - mLatchD.mTimestamp.mPosition; + // mLatchD.mFramesReleased is set in threadloop_mix() mLatchDValid = true; } } @@ -3091,6 +3092,18 @@ void AudioFlinger::MixerThread::threadLoop_mix() sleepTime = 0; standbyTime = systemTime() + standbyDelay; //TODO: delay standby when effects have a tail + + mLatchD.mFramesReleased.clear(); + { + Mutex::Autolock _l(mLock); + size_t size = mActiveTracks.size(); + for (size_t i = 0; i < size; i++) { + sp t = mActiveTracks[i].promote(); + if (t != 0) { + mLatchD.mFramesReleased.add(t.get(), t->mAudioTrackServerProxy->framesReleased()); + } + } + } } void AudioFlinger::MixerThread::threadLoop_sleepTime() diff --git a/services/audioflinger/Threads.h b/services/audioflinger/Threads.h index fd025b5..cda8095 100644 --- a/services/audioflinger/Threads.h +++ b/services/audioflinger/Threads.h @@ -819,6 +819,7 @@ private: struct { AudioTimestamp mTimestamp; uint32_t mUnpresentedFrames; + KeyedVector mFramesReleased; } mLatchD, mLatchQ; bool mLatchDValid; // true means mLatchD is valid, and clock it into latch at next opportunity bool mLatchQValid; // true means mLatchQ is valid diff --git a/services/audioflinger/Tracks.cpp b/services/audioflinger/Tracks.cpp index c0a75b9..8c2bee4 100644 --- a/services/audioflinger/Tracks.cpp +++ b/services/audioflinger/Tracks.cpp @@ -894,7 +894,15 @@ status_t AudioFlinger::PlaybackThread::Track::getTimestamp(AudioTimestamp& times uint32_t unpresentedFrames = ((int64_t) playbackThread->mLatchQ.mUnpresentedFrames * mSampleRate) / playbackThread->mSampleRate; - uint32_t framesWritten = mAudioTrackServerProxy->framesReleased(); + // FIXME Since we're using a raw pointer as the key, it is theoretically possible + // for a brand new track to share the same address as a recently destroyed + // track, and thus for us to get the frames released of the wrong track. + // It is unlikely that we would be able to call getTimestamp() so quickly + // right after creating a new track. Nevertheless, the index here should + // be changed to something that is unique. Or use a completely different strategy. + ssize_t i = playbackThread->mLatchQ.mFramesReleased.indexOfKey(this); + uint32_t framesWritten = i >= 0 ? + playbackThread->mLatchQ.mFramesReleased[i] : mAudioTrackServerProxy->framesReleased(); bool checkPreviousTimestamp = mPreviousValid && framesWritten >= mPreviousFramesWritten; if (framesWritten < unpresentedFrames) { mPreviousValid = false; -- cgit v1.1