image/DecodePool.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "DecodePool.h"
   7
   8 #include <algorithm>
   9
  10 #include "mozilla/ClearOnShutdown.h"
  11 #include "mozilla/DebugOnly.h"
  12 #include "mozilla/Monitor.h"
  13 #include "mozilla/ProfilerLabels.h"
  14 #include "mozilla/SchedulerGroup.h"
  15 #include "mozilla/Services.h"
  16 #include "mozilla/StaticPrefs_image.h"
  17 #include "mozilla/TaskController.h"
  18 #include "mozilla/TimeStamp.h"
  19 #include "nsCOMPtr.h"
  20 #include "nsIObserverService.h"
  21 #include "nsThreadManager.h"
  22 #include "nsThreadUtils.h"
  23 #include "nsXPCOMCIDInternal.h"
  24 #include "prsystem.h"
  25
  26 #include "Decoder.h"
  27 #include "IDecodingTask.h"
  28 #include "RasterImage.h"
  29
  30 #if defined(XP_WIN)
  31 #  include <objbase.h>
  32 #  include "mozilla/WindowsProcessMitigations.h"
  33 #endif
  34
  35 using std::max;
  36 using std::min;
  37
  38 namespace mozilla {
  39 namespace image {
  40
  41 ///////////////////////////////////////////////////////////////////////////////
  42 // DecodePool implementation.
  43 ///////////////////////////////////////////////////////////////////////////////
  44
  45 /* static */
  46 StaticRefPtr<DecodePool> DecodePool::sSingleton;
  47 /* static */
  48 uint32_t DecodePool::sNumCores = 0;
  49
  50 NS_IMPL_ISUPPORTS(DecodePool, nsIObserver)
  51
  52 /* static */
  53 void DecodePool::Initialize() {
  54   MOZ_ASSERT(NS_IsMainThread());
  55   sNumCores = max<int32_t>(PR_GetNumberOfProcessors(), 1);
  56   DecodePool::Singleton();
  57 }
  58
  59 /* static */
  60 DecodePool* DecodePool::Singleton() {
  61   if (!sSingleton) {
  62     MOZ_ASSERT(NS_IsMainThread());
  63     sSingleton = new DecodePool();
  64     ClearOnShutdown(&sSingleton);
  65   }
  66
  67   return sSingleton;
  68 }
  69
  70 /* static */
  71 uint32_t DecodePool::NumberOfCores() { return sNumCores; }
  72
  73 #if defined(XP_WIN)
  74 class IOThreadIniter final : public Runnable {
  75  public:
  76   explicit IOThreadIniter() : Runnable("image::IOThreadIniter") {}
  77
  78   NS_IMETHOD Run() override {
  79     MOZ_ASSERT(!NS_IsMainThread());
  80
  81     CoInitialize(nullptr);
  82
  83     return NS_OK;
  84   }
  85 };
  86 #endif
  87
  88 DecodePool::DecodePool() : mMutex("image::IOThread") {
  89   // Initialize the I/O thread.
  90 #if defined(XP_WIN)
  91   // On Windows we use the io thread to get icons from the system. Any thread
  92   // that makes system calls needs to call CoInitialize. And these system calls
  93   // (SHGetFileInfo) should only be called from one thread at a time, in case
  94   // we ever create more than one io thread. If win32k is locked down, we can't
  95   // call SHGetFileInfo anyway, so we don't need the initializer.
  96   nsCOMPtr<nsIRunnable> initer =
  97       IsWin32kLockedDown() ? nullptr : new IOThreadIniter();
  98   nsresult rv = NS_NewNamedThread("ImageIO", getter_AddRefs(mIOThread), initer);
  99 #else
 100   nsresult rv = NS_NewNamedThread("ImageIO", getter_AddRefs(mIOThread));
 101 #endif
 102   MOZ_RELEASE_ASSERT(NS_SUCCEEDED(rv) && mIOThread,
 103                      "Should successfully create image I/O thread");
 104
 105   nsCOMPtr<nsIObserverService> obsSvc = services::GetObserverService();
 106   if (obsSvc) {
 107     obsSvc->AddObserver(this, "xpcom-shutdown-threads", false);
 108   }
 109 }
 110
 111 DecodePool::~DecodePool() {
 112   MOZ_ASSERT(NS_IsMainThread(), "Must shut down DecodePool on main thread!");
 113 }
 114
 115 NS_IMETHODIMP
 116 DecodePool::Observe(nsISupports*, const char* aTopic, const char16_t*) {
 117   MOZ_ASSERT(strcmp(aTopic, "xpcom-shutdown-threads") == 0, "Unexpected topic");
 118
 119   mShuttingDown = true;
 120
 121   nsCOMPtr<nsIThread> ioThread;
 122
 123   {
 124     MutexAutoLock lock(mMutex);
 125     ioThread.swap(mIOThread);
 126   }
 127
 128   if (ioThread) {
 129     ioThread->Shutdown();
 130   }
 131
 132   return NS_OK;
 133 }
 134
 135 bool DecodePool::IsShuttingDown() const { return mShuttingDown; }
 136
 137 class DecodingTask final : public Task {
 138  public:
 139   explicit DecodingTask(RefPtr<IDecodingTask>&& aTask)
 140       : Task(false, aTask->Priority() == TaskPriority::eLow
 141                         ? EventQueuePriority::Normal
 142                         : EventQueuePriority::MediumHigh),
 143         mTask(aTask) {}
 144
 145   bool Run() override {
 146     mTask->Run();
 147     return true;
 148   }
 149
 150  private:
 151   RefPtr<IDecodingTask> mTask;
 152 };
 153
 154 void DecodePool::AsyncRun(IDecodingTask* aTask) {
 155   MOZ_ASSERT(aTask);
 156
 157   TaskController::Get()->AddTask(
 158       MakeAndAddRef<DecodingTask>((RefPtr<IDecodingTask>(aTask))));
 159 }
 160
 161 bool DecodePool::SyncRunIfPreferred(IDecodingTask* aTask,
 162                                     const nsCString& aURI) {
 163   MOZ_ASSERT(NS_IsMainThread());
 164   MOZ_ASSERT(aTask);
 165
 166   AUTO_PROFILER_LABEL_DYNAMIC_NSCSTRING("DecodePool::SyncRunIfPreferred",
 167                                         GRAPHICS, aURI);
 168
 169   if (aTask->ShouldPreferSyncRun()) {
 170     aTask->Run();
 171     return true;
 172   }
 173
 174   AsyncRun(aTask);
 175   return false;
 176 }
 177
 178 void DecodePool::SyncRunIfPossible(IDecodingTask* aTask,
 179                                    const nsCString& aURI) {
 180   MOZ_ASSERT(NS_IsMainThread());
 181   MOZ_ASSERT(aTask);
 182
 183   AUTO_PROFILER_LABEL_DYNAMIC_NSCSTRING("DecodePool::SyncRunIfPossible",
 184                                         GRAPHICS, aURI);
 185
 186   aTask->Run();
 187 }
 188
 189 already_AddRefed<nsIEventTarget> DecodePool::GetIOEventTarget() {
 190   MutexAutoLock threadPoolLock(mMutex);
 191   nsCOMPtr<nsIEventTarget> target = mIOThread;
 192   return target.forget();
 193 }
 194
 195 }  // namespace image
 196 }  // namespace mozilla