Reduce blocking time in file write (f6a2bff0) · Commits · e / os / android_frameworks_base

include/media/stagefright/MPEG4Writer.h

+8 −5

Original line number	Diff line number	Diff line
		@@ -98,6 +98,8 @@ private:
		List<MediaBuffer *> mSamples; // Sample data

		// Convenient constructor
		Chunk(): mTrack(NULL), mTimeStampUs(0) {}

		Chunk(Track track, int64_t timeUs, List<MediaBuffer > samples)
		: mTrack(track), mTimeStampUs(timeUs), mSamples(samples) {
		}
		@@ -124,13 +126,14 @@ private:
		void bufferChunk(const Chunk& chunk);

		// Write all buffered chunks from all tracks
		void writeChunks();
		void writeAllChunks();

		// Write a chunk if there is one
		status_t writeOneChunk();
		// Retrieve the proper chunk to write if there is one
		// Return true if a chunk is found; otherwise, return false.
		bool findChunkToWrite(Chunk *chunk);

		// Write the first chunk from the given ChunkInfo.
		void writeFirstChunk(ChunkInfo* info);
		// Actually write the given chunk to the file.
		void writeChunkToFile(Chunk* chunk);

		// Adjust other track media clock (presumably wall clock)
		// based on audio track media clock with the drift time.

media/libstagefright/MPEG4Writer.cpp

+49 −37

Original line number	Diff line number	Diff line
		@@ -1122,42 +1122,42 @@ void MPEG4Writer::bufferChunk(const Chunk& chunk) {
		CHECK("Received a chunk for a unknown track" == 0);
		}

		void MPEG4Writer::writeFirstChunk(ChunkInfo* info) {
		LOGV("writeFirstChunk: %p", info->mTrack);
		void MPEG4Writer::writeChunkToFile(Chunk* chunk) {
		LOGV("writeChunkToFile: %lld from %s track",
		chunk.mTimestampUs, chunk.mTrack->isAudio()? "audio": "video");

		List<Chunk>::iterator chunkIt = info->mChunks.begin();
		for (List<MediaBuffer *>::iterator it = chunkIt->mSamples.begin();
		it != chunkIt->mSamples.end(); ++it) {
		int32_t isFirstSample = true;
		while (!chunk->mSamples.empty()) {
		List<MediaBuffer *>::iterator it = chunk->mSamples.begin();

		off64_t offset = info->mTrack->isAvc()
		off64_t offset = chunk->mTrack->isAvc()
		? addLengthPrefixedSample_l(*it)
		: addSample_l(*it);
		if (it == chunkIt->mSamples.begin()) {
		info->mTrack->addChunkOffset(offset);
		}

		if (isFirstSample) {
		chunk->mTrack->addChunkOffset(offset);
		isFirstSample = false;
		}

		// Done with the current chunk.
		// Release all the samples in this chunk.
		while (!chunkIt->mSamples.empty()) {
		List<MediaBuffer *>::iterator it = chunkIt->mSamples.begin();
		(*it)->release();
		(*it) = NULL;
		chunkIt->mSamples.erase(it);
		chunk->mSamples.erase(it);
		}
		chunkIt->mSamples.clear();
		info->mChunks.erase(chunkIt);
		chunk->mSamples.clear();
		}

		void MPEG4Writer::writeChunks() {
		LOGV("writeChunks");
		void MPEG4Writer::writeAllChunks() {
		LOGV("writeAllChunks");
		size_t outstandingChunks = 0;
		while (!mChunkInfos.empty()) {
		List<ChunkInfo>::iterator it = mChunkInfos.begin();
		while (!it->mChunks.empty()) {
		CHECK_EQ(OK, writeOneChunk());
		Chunk chunk;
		if (findChunkToWrite(&chunk)) {
		writeChunkToFile(&chunk);
		++outstandingChunks;
		}
		}
		it->mTrack = NULL;
		mChunkInfos.erase(it);
		}
		@@ -1165,8 +1165,8 @@ void MPEG4Writer::writeChunks() {
		LOGD("%d chunks are written in the last batch", outstandingChunks);
		}

		status_t MPEG4Writer::writeOneChunk() {
		LOGV("writeOneChunk");
		bool MPEG4Writer::findChunkToWrite(Chunk *chunk) {
		LOGV("findChunkToWrite");

		// Find the smallest timestamp, and write that chunk out
		// XXX: What if some track is just too slow?
		@@ -1185,40 +1185,52 @@ status_t MPEG4Writer::writeOneChunk() {

		if (track == NULL) {
		LOGV("Nothing to be written after all");
		return OK;
		return false;
		}

		if (mIsFirstChunk) {
		mIsFirstChunk = false;
		}

		for (List<ChunkInfo>::iterator it = mChunkInfos.begin();
		it != mChunkInfos.end(); ++it) {
		if (it->mTrack == track) {
		writeFirstChunk(&(*it));
		chunk = (it->mChunks.begin());
		it->mChunks.erase(it->mChunks.begin());
		CHECK_EQ(chunk->mTrack, track);
		return true;
		}
		}
		return OK;

		return false;
		}

		void MPEG4Writer::threadFunc() {
		LOGV("threadFunc");

		prctl(PR_SET_NAME, (unsigned long)"MPEG4Writer", 0, 0, 0);

		Mutex::Autolock autoLock(mLock);
		while (!mDone) {
		{
		Mutex::Autolock autolock(mLock);
		Chunk chunk;
		bool chunkFound = false;

		while (!mDone && !(chunkFound = findChunkToWrite(&chunk))) {
		mChunkReadyCondition.wait(mLock);
		CHECK_EQ(writeOneChunk(), OK);
		}
		}

		{
		// Write ALL samples
		Mutex::Autolock autolock(mLock);
		writeChunks();
		// Actual write without holding the lock in order to
		// reduce the blocking time for media track threads.
		if (chunkFound) {
		mLock.unlock();
		writeChunkToFile(&chunk);
		mLock.lock();
		}
		}

		writeAllChunks();
		}

		status_t MPEG4Writer::startWriterThread() {
		LOGV("startWriterThread");