Bug 1429847 - Promote the GraphRunner thread. r=pehrsons

Differential Revision: https://phabricator.services.mozilla.com/D32499

--HG--
extra : moz-landing-system : lando

dom/media/GraphRunner.cpp

@@ -13,6 +13,7 @@
 #include "nsISupportsImpl.h"
 #include "prthread.h"
 #include "Tracing.h"
+#include "audio_thread_priority.h"
 
 namespace mozilla {
 
@@ -91,6 +92,10 @@ bool GraphRunner::OneIteration(GraphTime aStateEnd) {
 
 void GraphRunner::Run() {
   PR_SetCurrentThreadName("GraphRunner");
+
+  atp_handle* handle =
+      atp_promote_current_thread_to_real_time(0, mGraph->GraphRate());
+
   MonitorAutoLock lock(mMonitor);
   while (true) {
     while (mThreadState == ThreadState::Wait) {
@@ -106,6 +111,10 @@ void GraphRunner::Run() {
     mMonitor.Notify();
   }
 
+  if (handle) {
+    atp_demote_current_thread_from_real_time(handle);
+  }
+
   dom::WorkletThread::DeleteCycleCollectedJSContext();
 }
 

dom/media/moz.build

@@ -89,6 +89,7 @@ XPIDL_SOURCES += [
 XPIDL_MODULE = 'dom_media'
 
 EXPORTS += [
+    '../../third_party/rust/audio_thread_priority/audio_thread_priority.h',
     'ADTSDecoder.h',
     'ADTSDemuxer.h',
     'AsyncLogger.h',