dom/media/GraphRunner.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
   6
   7 #include "GraphRunner.h"
   8
   9 #include "GraphDriver.h"
  10 #include "MediaTrackGraph.h"
  11 #include "MediaTrackGraphImpl.h"
  12 #include "nsISupportsImpl.h"
  13 #include "nsISupportsPriority.h"
  14 #include "prthread.h"
  15 #include "Tracing.h"
  16 #include "audio_thread_priority.h"
  17 #ifdef MOZ_WIDGET_ANDROID
  18 #  include "AndroidProcess.h"
  19 #endif  // MOZ_WIDGET_ANDROID
  20
  21 namespace mozilla {
  22
  23 GraphRunner::GraphRunner(MediaTrackGraphImpl* aGraph,
  24                          already_AddRefed<nsIThread> aThread)
  25     : Runnable("GraphRunner"),
  26       mMonitor("GraphRunner::mMonitor"),
  27       mGraph(aGraph),
  28       mThreadState(ThreadState::Wait),
  29       mThread(aThread) {
  30   mThread->Dispatch(do_AddRef(this));
  31 }
  32
  33 GraphRunner::~GraphRunner() {
  34   MOZ_ASSERT(mThreadState == ThreadState::Shutdown);
  35 }
  36
  37 /* static */
  38 already_AddRefed<GraphRunner> GraphRunner::Create(MediaTrackGraphImpl* aGraph) {
  39   nsCOMPtr<nsIThread> thread;
  40   if (NS_WARN_IF(NS_FAILED(
  41           NS_NewNamedThread("GraphRunner", getter_AddRefs(thread))))) {
  42     return nullptr;
  43   }
  44   nsCOMPtr<nsISupportsPriority> supportsPriority = do_QueryInterface(thread);
  45   MOZ_ASSERT(supportsPriority);
  46   MOZ_ALWAYS_SUCCEEDS(
  47       supportsPriority->SetPriority(nsISupportsPriority::PRIORITY_HIGHEST));
  48
  49   return do_AddRef(new GraphRunner(aGraph, thread.forget()));
  50 }
  51
  52 void GraphRunner::Shutdown() {
  53   {
  54     MonitorAutoLock lock(mMonitor);
  55     MOZ_ASSERT(mThreadState == ThreadState::Wait);
  56     mThreadState = ThreadState::Shutdown;
  57     mMonitor.Notify();
  58   }
  59   mThread->Shutdown();
  60 }
  61
  62 auto GraphRunner::OneIteration(GraphTime aStateTime, GraphTime aIterationEnd,
  63                                AudioMixer* aMixer) -> IterationResult {
  64   TRACE("GraphRunner::OneIteration");
  65
  66   MonitorAutoLock lock(mMonitor);
  67   MOZ_ASSERT(mThreadState == ThreadState::Wait);
  68   mIterationState = Some(IterationState(aStateTime, aIterationEnd, aMixer));
  69
  70 #ifdef DEBUG
  71   if (const auto* audioDriver =
  72           mGraph->CurrentDriver()->AsAudioCallbackDriver()) {
  73     mAudioDriverThreadId = audioDriver->ThreadId();
  74   } else if (const auto* clockDriver =
  75                  mGraph->CurrentDriver()->AsSystemClockDriver()) {
  76     mClockDriverThread = clockDriver->Thread();
  77   } else {
  78     MOZ_CRASH("Unknown GraphDriver");
  79   }
  80 #endif
  81   // Signal that mIterationState was updated
  82   mThreadState = ThreadState::Run;
  83   mMonitor.Notify();
  84   // Wait for mIterationResult to update
  85   do {
  86     mMonitor.Wait();
  87   } while (mThreadState == ThreadState::Run);
  88
  89 #ifdef DEBUG
  90   mAudioDriverThreadId = std::thread::id();
  91   mClockDriverThread = nullptr;
  92 #endif
  93
  94   mIterationState = Nothing();
  95
  96   IterationResult result = std::move(mIterationResult);
  97   mIterationResult = IterationResult();
  98   return result;
  99 }
 100
 101 #ifdef MOZ_WIDGET_ANDROID
 102 namespace {
 103 void PromoteRenderingThreadAndroid() {
 104   MOZ_LOG(gMediaTrackGraphLog, LogLevel::Debug,
 105           ("GraphRunner default thread priority: %d",
 106            java::sdk::Process::GetThreadPriority(java::sdk::Process::MyTid())));
 107   java::sdk::Process::SetThreadPriority(
 108       java::sdk::Process::THREAD_PRIORITY_URGENT_AUDIO);
 109   MOZ_LOG(gMediaTrackGraphLog, LogLevel::Debug,
 110           ("GraphRunner promoted thread priority: %d",
 111            java::sdk::Process::GetThreadPriority(java::sdk::Process::MyTid())));
 112 }
 113 };      // namespace
 114 #endif  // MOZ_WIDGET_ANDROID
 115
 116 NS_IMETHODIMP GraphRunner::Run() {
 117 #ifndef XP_LINUX
 118   atp_handle* handle =
 119       atp_promote_current_thread_to_real_time(0, mGraph->GraphRate());
 120 #endif
 121
 122 #ifdef MOZ_WIDGET_ANDROID
 123   PromoteRenderingThreadAndroid();
 124 #endif  // MOZ_WIDGET_ANDROID
 125
 126   nsCOMPtr<nsIThreadInternal> threadInternal = do_QueryInterface(mThread);
 127   threadInternal->SetObserver(mGraph);
 128
 129   MonitorAutoLock lock(mMonitor);
 130   while (true) {
 131     while (mThreadState == ThreadState::Wait) {
 132       mMonitor.Wait();  // Wait for mIterationState to update or for shutdown
 133     }
 134     if (mThreadState == ThreadState::Shutdown) {
 135       break;
 136     }
 137     MOZ_DIAGNOSTIC_ASSERT(mIterationState.isSome());
 138     TRACE("GraphRunner::Run");
 139     mIterationResult = mGraph->OneIterationImpl(mIterationState->StateTime(),
 140                                                 mIterationState->IterationEnd(),
 141                                                 mIterationState->Mixer());
 142     // Signal that mIterationResult was updated
 143     mThreadState = ThreadState::Wait;
 144     mMonitor.Notify();
 145   }
 146
 147 #ifndef XP_LINUX
 148   if (handle) {
 149     atp_demote_current_thread_from_real_time(handle);
 150   }
 151 #endif
 152
 153   return NS_OK;
 154 }
 155
 156 bool GraphRunner::OnThread() const { return mThread->IsOnCurrentThread(); }
 157
 158 #ifdef DEBUG
 159 bool GraphRunner::InDriverIteration(const GraphDriver* aDriver) const {
 160   if (!OnThread()) {
 161     return false;
 162   }
 163
 164   if (const auto* audioDriver = aDriver->AsAudioCallbackDriver()) {
 165     return audioDriver->ThreadId() == mAudioDriverThreadId;
 166   }
 167
 168   if (const auto* clockDriver = aDriver->AsSystemClockDriver()) {
 169     return clockDriver->Thread() == mClockDriverThread;
 170   }
 171
 172   MOZ_CRASH("Unknown driver");
 173 }
 174 #endif
 175
 176 }  // namespace mozilla