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|
commit a9bc6108422a
Author: Karl Tomlinson <karlt+@karlt.net>
Date: Tue Oct 17 18:14:43 2017 +1300
Bug 1408276 - Move to LIFECYCLE_WAITING_FOR_MAIN_THREAD_CLEANUP at end of iteration. r=padenot, a=gchang
MozReview-Commit-ID: GbfIOPZPuGu
--HG--
extra : rebase_source : acc2bcee9a36d2b8f18826f08825895de5df0c1e
---
dom/media/GraphDriver.cpp | 27 +++++++++++++++++----------
dom/media/MediaStreamGraph.cpp | 32 +++++++++++++++++++++-----------
dom/media/MediaStreamGraphImpl.h | 12 +++++++++++-
3 files changed, 49 insertions(+), 22 deletions(-)
diff --git dom/media/GraphDriver.cpp dom/media/GraphDriver.cpp
index 7f6f386fdaca..13944338e3d7 100644
--- dom/media/GraphDriver.cpp
+++ dom/media/GraphDriver.cpp
@@ -284,8 +284,7 @@ SystemClockDriver::IsFallback()
void
ThreadedDriver::RunThread()
{
- bool stillProcessing = true;
- while (stillProcessing) {
+ while (true) {
mIterationStart = IterationEnd();
mIterationEnd += GetIntervalForIteration();
@@ -324,10 +323,16 @@ ThreadedDriver::RunThread()
(long)stateComputedTime,
(long)nextStateComputedTime));
- stillProcessing = mGraphImpl->OneIteration(nextStateComputedTime);
+ bool stillProcessing = mGraphImpl->OneIteration(nextStateComputedTime);
+ if (!stillProcessing) {
+ // Enter shutdown mode. The stable-state handler will detect this
+ // and complete shutdown if the graph does not get restarted.
+ mGraphImpl->SignalMainThreadCleanup();
+ return;
+ }
MonitorAutoLock lock(GraphImpl()->GetMonitor());
- if (NextDriver() && stillProcessing) {
+ if (NextDriver()) {
LOG(LogLevel::Debug, ("Switching to AudioCallbackDriver"));
RemoveCallback();
NextDriver()->SetGraphTime(this, mIterationStart, mIterationEnd);
@@ -1009,13 +1014,20 @@ AudioCallbackDriver::DataCallback(const AudioDataValue* aInputBuffer,
mGraphImpl->NotifyOutputData(aOutputBuffer, static_cast<size_t>(aFrames),
mSampleRate, mOutputChannels);
+ if (!stillProcessing) {
+ // Enter shutdown mode. The stable-state handler will detect this
+ // and complete shutdown if the graph does not get restarted.
+ mGraphImpl->SignalMainThreadCleanup();
+ return aFrames - 1;
+ }
+
bool switching = false;
{
MonitorAutoLock mon(mGraphImpl->GetMonitor());
switching = !!NextDriver();
}
- if (switching && stillProcessing) {
+ if (switching) {
// If the audio stream has not been started by the previous driver or
// the graph itself, keep it alive.
MonitorAutoLock mon(mGraphImpl->GetMonitor());
@@ -1032,11 +1044,6 @@ AudioCallbackDriver::DataCallback(const AudioDataValue* aInputBuffer,
return aFrames - 1;
}
- if (!stillProcessing) {
- LOG(LogLevel::Debug,
- ("Stopping audio thread for MediaStreamGraph %p", this));
- return aFrames - 1;
- }
return aFrames;
}
diff --git dom/media/MediaStreamGraph.cpp dom/media/MediaStreamGraph.cpp
index 3a742aafe9b2..6420e038a8fe 100644
--- dom/media/MediaStreamGraph.cpp
+++ dom/media/MediaStreamGraph.cpp
@@ -1193,11 +1193,13 @@ MediaStreamGraphImpl::PrepareUpdatesToMainThreadState(bool aFinalUpdate)
}
}
- // Don't send the message to the main thread if it's not going to have
- // any work to do.
- if (aFinalUpdate ||
- !mUpdateRunnables.IsEmpty() ||
- !mStreamUpdates.IsEmpty()) {
+ // If this is the final update, then a stable state event will soon be
+ // posted just before this thread finishes, and so there is no need to also
+ // post here.
+ if (!aFinalUpdate &&
+ // Don't send the message to the main thread if it's not going to have
+ // any work to do.
+ !(mUpdateRunnables.IsEmpty() && mStreamUpdates.IsEmpty())) {
EnsureStableStateEventPosted();
}
}
@@ -1430,12 +1432,7 @@ MediaStreamGraphImpl::UpdateMainThreadState()
(IsEmpty() && mBackMessageQueue.IsEmpty());
PrepareUpdatesToMainThreadState(finalUpdate);
if (finalUpdate) {
- // Enter shutdown mode. The stable-state handler will detect this
- // and complete shutdown. Destroy any streams immediately.
- LOG(LogLevel::Debug,
- ("MediaStreamGraph %p waiting for main thread cleanup", this));
- // We'll shut down this graph object if it does not get restarted.
- mLifecycleState = LIFECYCLE_WAITING_FOR_MAIN_THREAD_CLEANUP;
+ // Enter shutdown mode when this iteration is completed.
// No need to Destroy streams here. The main-thread owner of each
// stream is responsible for calling Destroy on them.
return false;
@@ -1861,6 +1858,19 @@ MediaStreamGraphImpl::EnsureStableStateEventPosted()
mAbstractMainThread->Dispatch(event.forget());
}
+void
+MediaStreamGraphImpl::SignalMainThreadCleanup()
+{
+ MOZ_ASSERT(mDriver->OnThread());
+
+ MonitorAutoLock lock(mMonitor);
+ LOG(LogLevel::Debug,
+ ("MediaStreamGraph %p waiting for main thread cleanup", this));
+ mLifecycleState =
+ MediaStreamGraphImpl::LIFECYCLE_WAITING_FOR_MAIN_THREAD_CLEANUP;
+ EnsureStableStateEventPosted();
+}
+
void
MediaStreamGraphImpl::AppendMessage(UniquePtr<ControlMessage> aMessage)
{
diff --git dom/media/MediaStreamGraphImpl.h dom/media/MediaStreamGraphImpl.h
index dfea12bca3a8..dce49da39166 100644
--- dom/media/MediaStreamGraphImpl.h
+++ dom/media/MediaStreamGraphImpl.h
@@ -197,6 +197,14 @@ public:
*/
bool OneIteration(GraphTime aStateEnd);
+ /**
+ * Called from the driver, when the graph thread is about to stop, to tell
+ * the main thread to attempt to begin cleanup. The main thread may either
+ * shutdown or revive the graph depending on whether it receives new
+ * messages.
+ */
+ void SignalMainThreadCleanup();
+
bool Running() const
{
mMonitor.AssertCurrentThreadOwns();
@@ -720,7 +728,9 @@ public:
LIFECYCLE_WAITING_FOR_STREAM_DESTRUCTION
};
/**
- * Modified only on the main thread in mMonitor.
+ * Modified only in mMonitor. Transitions to
+ * LIFECYCLE_WAITING_FOR_MAIN_THREAD_CLEANUP occur on the graph thread at
+ * the end of an iteration. All other transitions occur on the main thread.
*/
LifecycleState mLifecycleState;
/**
|
