Bug 1817305 - Start the DataStorageTimer only when there is something to write, r=keeler. (671f8253) · Commits · Dan Ballard / Mullvad Browser

security/manager/ssl/DataStorage.cpp

+32 −9

Original line number	Diff line number	Diff line
		@@ -85,6 +85,7 @@ mozilla::StaticAutoPtr<DataStorage::DataStorages> DataStorage::sDataStorages;
		DataStorage::DataStorage(const nsString& aFilename)
		: mMutex("DataStorage::mMutex"),
		mPendingWrite(false),
		mTimerArmed(false),
		mShuttingDown(false),
		mInitCalled(false),
		mReadyMonitor("DataStorage::mReadyMonitor"),
		@@ -174,15 +175,8 @@ nsresult DataStorage::Init() {
		mBackgroundTaskQueue = TaskQueue::Create(target.forget(), "PSM DataStorage");

		// For test purposes, we can set the write timer to be very fast.
		uint32_t timerDelayMS = Preferences::GetInt("test.datastorage.write_timer_ms",
		mTimerDelayMS = Preferences::GetInt("test.datastorage.write_timer_ms",
		sDataStorageDefaultTimerDelay);
		rv = NS_NewTimerWithFuncCallback(
		getter_AddRefs(mTimer), DataStorage::TimerCallback, this, timerDelayMS,
		nsITimer::TYPE_REPEATING_SLACK_LOW_PRIORITY, "DataStorageTimer",
		mBackgroundTaskQueue);
		if (NS_WARN_IF(NS_FAILED(rv))) {
		return rv;
		}

		rv = AsyncReadData(lock);
		if (NS_FAILED(rv)) {
		@@ -589,6 +583,7 @@ nsresult DataStorage::PutInternal(const nsCString& aKey, Entry& aEntry,

		if (aType == DataStorage_Persistent) {
		mPendingWrite = true;
		ArmTimer(aProofOfLock);
		}

		return NS_OK;
		@@ -603,6 +598,7 @@ void DataStorage::Remove(const nsCString& aKey, DataStorageType aType) {

		if (aType == DataStorage_Persistent) {
		mPendingWrite = true;
		ArmTimer(lock);
		}
		}

		@@ -707,6 +703,11 @@ nsresult DataStorage::AsyncWriteData(const MutexAutoLock& /aProofOfLock/) {
		nsCOMPtr<nsIRunnable> job(new Writer(output, this));
		nsresult rv = mBackgroundTaskQueue->Dispatch(job.forget());
		mPendingWrite = false;
		if (mTimerArmed) {
		rv = mTimer->Cancel();
		Unused << NS_WARN_IF(NS_FAILED(rv));
		mTimerArmed = false;
		}
		if (NS_WARN_IF(NS_FAILED(rv))) {
		return rv;
		}
		@@ -732,6 +733,7 @@ nsresult DataStorage::Clear() {
		void DataStorage::TimerCallback(nsITimer* aTimer, void* aClosure) {
		RefPtr<DataStorage> aDataStorage = (DataStorage*)aClosure;
		MutexAutoLock lock(aDataStorage->mMutex);
		aDataStorage->mTimerArmed = false;
		Unused << aDataStorage->AsyncWriteData(lock);
		}

		@@ -749,6 +751,27 @@ void DataStorage::NotifyObservers(const char* aTopic) {
		}
		}

		void DataStorage::ArmTimer(const MutexAutoLock& /aProofOfLock/) {
		mMutex.AssertCurrentThreadOwns();
		if (mTimerArmed) {
		return;
		}

		if (!mTimer) {
		mTimer = NS_NewTimer(mBackgroundTaskQueue);
		if (NS_WARN_IF(!mTimer)) {
		return;
		}
		}

		nsresult rv = mTimer->InitWithNamedFuncCallback(
		DataStorage::TimerCallback, this, mTimerDelayMS, nsITimer::TYPE_ONE_SHOT,
		"DataStorageTimer");
		Unused << NS_WARN_IF(NS_FAILED(rv));

		mTimerArmed = true;
		}

		void DataStorage::ShutdownTimer() {
		MOZ_ASSERT(NS_IsMainThread());
		if (mTimer) {

security/manager/ssl/DataStorage.h

+4 −1

Original line number	Diff line number	Diff line
		@@ -136,6 +136,7 @@ class DataStorage : public nsIObserver {
		// Return true if this data storage is ready to be used.
		bool IsReady();

		void ArmTimer(const MutexAutoLock& aProofOfLock);
		void ShutdownTimer();

		private:
		@@ -201,13 +202,15 @@ class DataStorage : public nsIObserver {
		nsCOMPtr<nsIFile> mBackingFile MOZ_GUARDED_BY(mMutex);
		bool mPendingWrite MOZ_GUARDED_BY(
		mMutex); // true if a write is needed but hasn't been dispatched
		bool mTimerArmed MOZ_GUARDED_BY(mMutex);
		bool mShuttingDown MOZ_GUARDED_BY(mMutex);
		RefPtr<TaskQueue> mBackgroundTaskQueue MOZ_GUARDED_BY(mMutex);
		// (End list of members protected by mMutex)

		nsCOMPtr<nsITimer> mTimer; // Must only be accessed on the main thread
		nsCOMPtr<nsITimer> mTimer;

		mozilla::Atomic<bool> mInitCalled; // Indicates that Init() has been called.
		uint32_t mTimerDelayMS;

		Monitor mReadyMonitor; // Do not acquire this at the same time as mMutex.
		bool mReady MOZ_GUARDED_BY(mReadyMonitor); // Indicates that saved data has