Issue #2654 - Remove pre-allocated process manager.

Resolves #2654

dom/browser-element/mochitest/priority/mochitest.ini

@@ -13,7 +13,5 @@ support-files =
 
 [test_Simple.html]
 [test_HighPriority.html]
-[test_Preallocated.html]
-disabled = bug 968604, bug 987164
 [test_WebGLContextLost.html]
 disabled = bug 865844

dom/ipc/ContentChild.cpp

@@ -559,7 +559,6 @@ ContentChild::Init(MessageLoop* aIOLoop,
 #endif
 
   SendGetProcessAttributes(&mID, &mIsForBrowser);
-  InitProcessAttributes();
 
 #ifdef NS_PRINTING
   // Force the creation of the nsPrintingProxy so that it's IPC counterpart,
@@ -570,12 +569,6 @@ ContentChild::Init(MessageLoop* aIOLoop,
   return true;
 }
 
-void
-ContentChild::InitProcessAttributes()
-{
-  SetProcessName(NS_LITERAL_STRING("Web Content"), true);
-}
-
 void
 ContentChild::SetProcessName(const nsAString& aName, bool aDontOverride)
 {
@@ -1248,15 +1241,6 @@ ContentChild::RecvBidiKeyboardNotify(const bool& aIsLangRTL,
   return true;
 }
 
-static CancelableRunnable* sFirstIdleTask;
-
-static void FirstIdle(void)
-{
-  MOZ_ASSERT(sFirstIdleTask);
-  sFirstIdleTask = nullptr;
-  ContentChild::GetSingleton()->SendFirstIdle();
-}
-
 mozilla::jsipc::PJavaScriptChild *
 ContentChild::AllocPJavaScriptChild()
 {
@@ -1325,22 +1309,6 @@ ContentChild::RecvPBrowserConstructor(PBrowserChild* aActor,
     os->NotifyObservers(tc, "tab-child-created", nullptr);
   }
 
-  static bool hasRunOnce = false;
-  if (!hasRunOnce) {
-      hasRunOnce = true;
-
-    MOZ_ASSERT(!sFirstIdleTask);
-    RefPtr<CancelableRunnable> firstIdleTask = NewCancelableRunnableFunction(FirstIdle);
-    sFirstIdleTask = firstIdleTask;
-    MessageLoop::current()->PostIdleTask(firstIdleTask.forget());
-
-    // Redo InitProcessAttributes() when the app or browser is really
-    // launching so the attributes will be correct.
-    mID = aCpID;
-    mIsForBrowser = aIsForBrowser;
-    InitProcessAttributes();
-  }
-
   return true;
 }
 
@@ -1789,9 +1757,6 @@ ContentChild::ActorDestroy(ActorDestroyReason why)
   // keep persistent state.
   ProcessChild::QuickExit();
 #else
-  if (sFirstIdleTask) {
-    sFirstIdleTask->Cancel();
-  }
 
   nsHostObjectProtocolHandler::RemoveDataEntries();
 
@@ -2085,16 +2050,6 @@ ContentChild::RecvCycleCollect()
   return true;
 }
 
-static void
-PreloadSlowThings()
-{
-  // This fetches and creates all the built-in stylesheets.
-  nsLayoutStylesheetCache::Get()->UserContentSheet();
-
-  TabChild::PreloadSlowThings();
-
-}
-
 bool
 ContentChild::RecvAppInfo(const nsCString& version, const nsCString& buildID,
                           const nsCString& name, const nsCString& UAName,
@@ -2110,25 +2065,6 @@ ContentChild::RecvAppInfo(const nsCString& version, const nsCString& buildID,
   return true;
 }
 
-bool
-ContentChild::RecvAppInit()
-{
-  if (!Preferences::GetBool("dom.ipc.processPrelaunch.enabled", false)) {
-    return true;
-  }
-
-  // If we're part of the mozbrowser machinery, go ahead and start
-  // preloading things.  We can only do this for mozbrowser because
-  // PreloadSlowThings() may set the docshell of the first TabChild
-  // inactive, and we can only safely restore it to active from
-  // BrowserElementChild.js.
-  if (mIsForBrowser) {
-    PreloadSlowThings();
-  }
-
-  return true;
-}
-
 bool
 ContentChild::RecvInitServiceWorkers(const ServiceWorkerConfiguration& aConfig)
 {

dom/ipc/ContentChild.h

@@ -91,8 +91,6 @@ class ContentChild final : public PContentChild
             base::ProcessId aParentPid,
             IPC::Channel* aChannel);
 
-  void InitProcessAttributes();
-
   void InitXPCOM();
 
   void InitGraphicsDeviceData();
@@ -380,8 +378,6 @@ class ContentChild final : public PContentChild
                            const nsCString& name, const nsCString& UAName,
                            const nsCString& ID, const nsCString& vendor) override;
 
-  virtual bool RecvAppInit() override;
-
   virtual bool
   RecvInitServiceWorkers(const ServiceWorkerConfiguration& aConfig) override;
 

dom/ipc/ContentParent.cpp

@@ -146,7 +146,6 @@
 #include "nsThreadUtils.h"
 #include "nsToolkitCompsCID.h"
 #include "nsWidgetsCID.h"
-#include "PreallocatedProcessManager.h"
 #include "ProcessPriorityManager.h"
 #include "SandboxHal.h"
 #include "ScreenManagerParent.h"
@@ -490,25 +489,6 @@ static const char* sObserverTopics[] = {
   "cacheservice:empty-cache",
 };
 
-// PreallocateAppProcess is called by the PreallocatedProcessManager.
-// ContentParent then takes this process back within
-// GetNewOrPreallocatedAppProcess.
-/*static*/ already_AddRefed<ContentParent>
-ContentParent::PreallocateAppProcess()
-{
-  RefPtr<ContentParent> process =
-    new ContentParent(/* aOpener = */ nullptr,
-                      /* isForBrowserElement = */ false,
-                      /* isForPreallocated = */ true);
-
-  if (!process->LaunchSubprocess(PROCESS_PRIORITY_PREALLOC)) {
-    return nullptr;
-  }
-
-  process->Init();
-  return process.forget();
-}
-
 /*static*/ void
 ContentParent::StartUp()
 {
@@ -530,9 +510,6 @@ ContentParent::StartUp()
 
   BackgroundChild::Startup();
 
-  // Try to preallocate a process that we can transform into an app later.
-  PreallocatedProcessManager::AllocateAfterDelay();
-
   sDisableUnsafeCPOWWarnings = PR_GetEnv("DISABLE_UNSAFE_CPOW_WARNINGS");
 }
 
@@ -637,23 +614,14 @@ ContentParent::GetNewOrUsedBrowserProcess(bool aForBrowserElement,
     } while (currIdx != startIdx);
   }
 
-  // Try to take and transform the preallocated process into browser.
-  RefPtr<ContentParent> p = PreallocatedProcessManager::Take();
-  if (p) {
-    p->TransformPreallocatedIntoBrowser(aOpener);
-  } else {
-    // Failed in using the preallocated process: fork from the chrome process.
-    p = new ContentParent(aOpener,
-                          aForBrowserElement,
-                          /* isForPreallocated = */ false);
-
-    if (!p->LaunchSubprocess(aPriority)) {
-      return nullptr;
-    }
+  RefPtr<ContentParent> p = new ContentParent(aOpener, aForBrowserElement);
 
-    p->Init();
+  if (!p->LaunchSubprocess(aPriority)) {
+    return nullptr;
   }
 
+  p->Init();
+
   p->mLargeAllocationProcess = aLargeAllocationProcess;
 
   p->ForwardKnownInfo();
@@ -711,12 +679,6 @@ ContentParent::SendAsyncUpdate(nsIWidget* aWidget)
 ContentParent::SendAsyncUpdate(nsIWidget* aWidget) {}
 #endif
 
-bool
-ContentParent::PreallocatedProcessReady()
-{
-  return true;
-}
-
 bool
 ContentParent::RecvCreateChildProcess(const IPCTabContext& aContext,
                                       const hal::ProcessPriority& aPriority,
@@ -1132,15 +1094,6 @@ ContentParent::SetPriorityAndCheckIsAlive(ProcessPriority aPriority)
   return true;
 }
 
-void
-ContentParent::TransformPreallocatedIntoBrowser(ContentParent* aOpener)
-{
-  // Reset mIsForBrowser and mOSPrivileges for browser.
-  mMetamorphosed = true;
-  mOpener = aOpener;
-  mIsForBrowser = true;
-}
-
 void
 ContentParent::ShutDownProcess(ShutDownMethod aMethod)
 {
@@ -1691,20 +1644,14 @@ ContentParent::LaunchSubprocess(ProcessPriority aInitialPriority /* = PROCESS_PR
 }
 
 ContentParent::ContentParent(ContentParent* aOpener,
-                             bool aIsForBrowser,
-                             bool aIsForPreallocated)
+                             bool aIsForBrowser)
   : nsIContentParent()
   , mOpener(aOpener)
   , mIsForBrowser(aIsForBrowser)
-  , mIsPreallocated(aIsForPreallocated)
   , mLargeAllocationProcess(false)
 {
   InitializeMembers();  // Perform common initialization.
 
-  // No more than one of aIsForBrowser, aIsForPreallocated should be
-  // true.
-  MOZ_ASSERT(aIsForBrowser + aIsForPreallocated <= 1);
-
   mMetamorphosed = true;
 
   // Insert ourselves into the global linked list of ContentParent objects.
@@ -1814,11 +1761,6 @@ ContentParent::InitInternal(ProcessPriority aInitialPriority,
     }
   }
 
-  if (gAppData) {
-    // Sending all information to content process.
-    Unused << SendAppInit();
-  }
-
   nsStyleSheetService *sheetService = nsStyleSheetService::GetInstance();
   if (sheetService) {
     // This looks like a lot of work, but in a normal browser session we just
@@ -2118,17 +2060,6 @@ ContentParent::RecvGetShowPasswordSetting(bool* showPassword)
   return true;
 }
 
-bool
-ContentParent::RecvFirstIdle()
-{
-  // When the ContentChild goes idle, it sends us a FirstIdle message
-  // which we use as a good time to prelaunch another process. If we
-  // prelaunch any sooner than this, then we'll be competing with the
-  // child process and slowing it down.
-  PreallocatedProcessManager::AllocateAfterDelay();
-  return true;
-}
-
 bool
 ContentParent::RecvAudioChannelChangeDefVolChannel(const int32_t& aChannel,
                                                    const bool& aHidden)
@@ -2513,19 +2444,11 @@ ContentParent::KillHard(const char* aReason)
                         otherProcessHandle, /*force=*/true));
 }
 
-bool
-ContentParent::IsPreallocated() const
-{
-  return mIsPreallocated;
-}
-
 void
 ContentParent::FriendlyName(nsAString& aName, bool aAnonymize)
 {
   aName.Truncate();
-  if (IsPreallocated()) {
-    aName.AssignLiteral("(Preallocated)");
-  } else if (mIsForBrowser) {
+  if (mIsForBrowser) {
     aName.AssignLiteral("Browser");
   } else if (aAnonymize) {
     aName.AssignLiteral("<anonymized-name>");