Merge "Changes to the prefetcher to allow for bursts of data to be... (2e3761ba) · Commits · e / os / android_frameworks_base

media/libstagefright/Prefetcher.cpp

+50 −12

Original line number	Diff line number	Diff line
		@@ -58,13 +58,14 @@ private:
		status_t mFinalStatus;
		int64_t mSeekTimeUs;
		int64_t mCacheDurationUs;
		size_t mCacheSizeBytes;
		bool mPrefetcherStopped;
		bool mCurrentlyPrefetching;

		List<MediaBuffer *> mCachedBuffers;

		// Returns true iff source is currently caching.
		bool getCacheDurationUs(int64_t *durationUs);
		bool getCacheDurationUs(int64_t durationUs, size_t totalSize = NULL);

		void updateCacheDuration_l();
		void clearCache_l();
		@@ -125,21 +126,31 @@ int Prefetcher::ThreadWrapper(void *me) {
		return 0;
		}

		// Cache about 10secs for each source.
		static int64_t kMaxCacheDurationUs = 10000000ll;
		// Cache at most 1 min for each source.
		static int64_t kMaxCacheDurationUs = 60 * 1000000ll;

		// At the same time cache at most 5MB per source.
		static size_t kMaxCacheSizeBytes = 5 * 1024 * 1024;

		// If the amount of cached data drops below this,
		// fill the cache up to the max duration again.
		static int64_t kLowWaterDurationUs = 5000000ll;

		void Prefetcher::threadFunc() {
		bool fillingCache = false;

		for (;;) {
		sp<PrefetchedSource> minSource;
		int64_t minCacheDurationUs = -1;

		{
		Mutex::Autolock autoLock(mLock);
		if (mDone) {
		break;
		}
		mCondition.waitRelative(mLock, 10000000ll);
		mCondition.waitRelative(
		mLock, fillingCache ? 10000000ll : 1000000000ll);

		int64_t minCacheDurationUs = -1;
		ssize_t minIndex = -1;
		for (size_t i = 0; i < mSources.size(); ++i) {
		sp<PrefetchedSource> source = mSources[i].promote();
		@@ -149,11 +160,18 @@ void Prefetcher::threadFunc() {
		}

		int64_t cacheDurationUs;
		if (!source->getCacheDurationUs(&cacheDurationUs)) {
		size_t cacheSizeBytes;
		if (!source->getCacheDurationUs(&cacheDurationUs, &cacheSizeBytes)) {
		continue;
		}

		if (cacheDurationUs >= kMaxCacheDurationUs) {
		if (cacheSizeBytes > kMaxCacheSizeBytes) {
		LOGI("max cache size reached");
		continue;
		}

		if (mSources.size() > 1 && cacheDurationUs >= kMaxCacheDurationUs) {
		LOGI("max duration reached, size = %d bytes", cacheSizeBytes);
		continue;
		}

		@@ -165,15 +183,27 @@ void Prefetcher::threadFunc() {
		}

		if (minIndex < 0) {
		if (fillingCache) {
		LOGV("[%p] done filling the cache, above high water mark.",
		this);
		fillingCache = false;
		}
		continue;
		}
		}

		if (!fillingCache && minCacheDurationUs < kLowWaterDurationUs) {
		LOGI("[%p] cache below low water mark, filling cache.", this);
		fillingCache = true;
		}

		if (fillingCache) {
		// Make sure not to hold the lock while calling into the source.
		// The lock guards the list of sources, not the individual sources
		// themselves.
		minSource->cacheMore();
		}
		}

		Mutex::Autolock autoLock(mLock);
		for (size_t i = 0; i < mSources.size(); ++i) {
		@@ -250,6 +280,7 @@ PrefetchedSource::PrefetchedSource(
		mReachedEOS(false),
		mSeekTimeUs(0),
		mCacheDurationUs(0),
		mCacheSizeBytes(0),
		mPrefetcherStopped(false),
		mCurrentlyPrefetching(false) {
		}
		@@ -323,6 +354,7 @@ status_t PrefetchedSource::read(
		out = mCachedBuffers.begin();
		mCachedBuffers.erase(mCachedBuffers.begin());
		updateCacheDuration_l();
		mCacheSizeBytes -= (*out)->size();

		return OK;
		}
		@@ -331,10 +363,14 @@ sp<MetaData> PrefetchedSource::getFormat() {
		return mSource->getFormat();
		}

		bool PrefetchedSource::getCacheDurationUs(int64_t *durationUs) {
		bool PrefetchedSource::getCacheDurationUs(
		int64_t durationUs, size_t totalSize) {
		Mutex::Autolock autoLock(mLock);

		*durationUs = mCacheDurationUs;
		if (totalSize != NULL) {
		*totalSize = mCacheSizeBytes;
		}

		if (!mStarted \|\| mReachedEOS) {
		return false;
		@@ -397,6 +433,7 @@ void PrefetchedSource::cacheMore() {

		mCachedBuffers.push_back(copy);
		updateCacheDuration_l();
		mCacheSizeBytes += copy->size();

		mCurrentlyPrefetching = false;
		mCondition.signal();
		@@ -425,6 +462,7 @@ void PrefetchedSource::clearCache_l() {
		}

		updateCacheDuration_l();
		mCacheSizeBytes = 0;
		}

		void PrefetchedSource::onPrefetcherStopped() {