Merge "libaudiohal@aidl: Synchronize commands sending" into main (82ad2756) · Commits · e / os / android_frameworks_av

media/libaudiohal/impl/StreamHalAidl.cpp

+23 −19

Original line number	Diff line number	Diff line
		@@ -506,6 +506,8 @@ status_t StreamHalAidl::sendCommand(
		"%s %s: must be invoked from the worker thread (%d)",
		__func__, command.toString().c_str(), workerTid);
		}
		{
		std::lock_guard l(mCommandReplyLock);
		if (!mContext.getCommandMQ()->writeBlocking(&command, 1)) {
		ALOGE("%s: failed to write command %s to MQ", __func__, command.toString().c_str());
		return NOT_ENOUGH_DATA;
		@@ -515,7 +517,8 @@ status_t StreamHalAidl::sendCommand(
		reply = &localReply;
		}
		if (!mContext.getReplyMQ()->readBlocking(reply, 1)) {
		ALOGE("%s: failed to read from reply MQ, command %s", __func__, command.toString().c_str());
		ALOGE("%s: failed to read from reply MQ, command %s",
		__func__, command.toString().c_str());
		return NOT_ENOUGH_DATA;
		}
		{
		@@ -528,6 +531,7 @@ status_t StreamHalAidl::sendCommand(
		mLastReply = *reply;
		mLastReplyExpirationNs = uptimeNanos() + mLastReplyLifeTimeNs;
		}
		}
		switch (reply->status) {
		case STATUS_OK: return OK;
		case STATUS_BAD_VALUE: return BAD_VALUE;

+11 −0

Original line number	Diff line number	Diff line
		@@ -243,6 +243,15 @@ class StreamHalAidl : public virtual StreamHalInterface, public ConversionHelper
		const bool mIsInput;
		const audio_config_base_t mConfig;
		const StreamContextAidl mContext;
		// This lock is used to make sending of a command and receiving a reply an atomic
		// operation. Otherwise, when two threads are trying to send a command, they may both advance to
		// reading of the reply once the HAL has consumed the command from the MQ, and that creates a
		// race condition between them.
		//
		// Note that only access to command and reply MQs needs to be protected because the data MQ is
		// only accessed by the I/O thread. Also, there is no need to protect lookup operations on the
		// queues as they are thread-safe, only send/receive operation must be protected.
		std::mutex mCommandReplyLock;

		private:
		static audio_config_base_t configToBase(const audio_config& config) {
		@@ -256,6 +265,8 @@ class StreamHalAidl : public virtual StreamHalInterface, public ConversionHelper
		std::lock_guard l(mLock);
		return mLastReply.state;
		}
		// Note: Since `sendCommand` takes mLock while holding mCommandReplyLock, never call
		// it with `mLock` being held.
		status_t sendCommand(
		const ::aidl::android::hardware::audio::core::StreamDescriptor::Command &command,
		::aidl::android::hardware::audio::core::StreamDescriptor::Reply* reply = nullptr,