Bug 1337537 - Move Dispatcher.{cpp,h} to xpcom/threads (r=froydnj)

MozReview-Commit-ID: AYyKynUv4bX

dom/base/Dispatcher.h

@@ -1,83 +0,0 @@
-/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim: set ts=8 sts=2 et sw=2 tw=80: */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#ifndef mozilla_dom_Dispatcher_h
-#define mozilla_dom_Dispatcher_h
-
-#include "mozilla/AlreadyAddRefed.h"
-#include "mozilla/TaskCategory.h"
-#include "nsISupports.h"
-
-class nsIEventTarget;
-class nsIRunnable;
-
-// This file defines basic functionality for dispatching runnables to various
-// groups: either the SystemGroup or a DocGroup or TabGroup. Ideally all
-// runnables destined for the main thread should be dispatched to a group
-// instead so that we know what kind of web content they'll be
-// touching. Runnables sent to the SystemGroup never touch web
-// content. Runnables sent to a DocGroup can only touch documents belonging to
-// that DocGroup. Runnables sent to a TabGroup can touch any document in any of
-// the tabs belonging to the TabGroup.
-
-namespace mozilla {
-class AbstractThread;
-namespace dom {
-class TabGroup;
-
-// This trait should be attached to classes like nsIGlobalObject and nsIDocument
-// that have a DocGroup or TabGroup attached to them. The methods here should
-// delegate to the DocGroup or TabGroup. We can't use the Dispatcher class
-// directly because it inherits from nsISupports.
-class DispatcherTrait {
-public:
-  // This method may or may not be safe off of the main thread. For nsIDocument
-  // it is safe. For nsIGlobalWindow it is not safe.
-  virtual nsresult Dispatch(const char* aName,
-                            TaskCategory aCategory,
-                            already_AddRefed<nsIRunnable>&& aRunnable);
-
-  // This method may or may not be safe off of the main thread. For nsIDocument
-  // it is safe. For nsIGlobalWindow it is not safe. The nsIEventTarget can
-  // always be used off the main thread.
-  virtual nsIEventTarget* EventTargetFor(TaskCategory aCategory) const;
-
-  // Must be called on the main thread. The AbstractThread can always be used
-  // off the main thread.
-  virtual AbstractThread* AbstractMainThreadFor(TaskCategory aCategory);
-};
-
-// Base class for DocGroup and TabGroup.
-class Dispatcher : public nsISupports {
-public:
-  // This method is always safe to call off the main thread.
-  virtual nsresult Dispatch(const char* aName,
-                            TaskCategory aCategory,
-                            already_AddRefed<nsIRunnable>&& aRunnable) = 0;
-
-  // This method is always safe to call off the main thread. The nsIEventTarget
-  // can always be used off the main thread.
-  virtual nsIEventTarget* EventTargetFor(TaskCategory aCategory) const = 0;
-
-  // Must be called on the main thread. The AbstractThread can always be used
-  // off the main thread.
-  virtual AbstractThread* AbstractMainThreadFor(TaskCategory aCategory) = 0;
-
-  // This method performs a safe cast. It returns null if |this| is not of the
-  // requested type.
-  virtual TabGroup* AsTabGroup() { return nullptr; }
-
-protected:
-  virtual already_AddRefed<nsIEventTarget>
-  CreateEventTargetFor(TaskCategory aCategory);
-
-  static Dispatcher* FromEventTarget(nsIEventTarget* aEventTarget);
-};
-
-} // namespace dom
-} // namespace mozilla
-
-#endif // mozilla_dom_Dispatcher_h

dom/base/DispatcherTrait.cpp

@@ -0,0 +1,45 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/dom/DispatcherTrait.h"
+
+#include "mozilla/AbstractThread.h"
+#include "nsINamed.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+nsresult
+DispatcherTrait::Dispatch(const char* aName,
+                          TaskCategory aCategory,
+                          already_AddRefed<nsIRunnable>&& aRunnable)
+{
+  nsCOMPtr<nsIRunnable> runnable(aRunnable);
+  if (aName) {
+    if (nsCOMPtr<nsINamed> named = do_QueryInterface(runnable)) {
+      named->SetName(aName);
+    }
+  }
+  if (NS_IsMainThread()) {
+    return NS_DispatchToCurrentThread(runnable.forget());
+  } else {
+    return NS_DispatchToMainThread(runnable.forget());
+  }
+}
+
+nsIEventTarget*
+DispatcherTrait::EventTargetFor(TaskCategory aCategory) const
+{
+  nsCOMPtr<nsIEventTarget> main = do_GetMainThread();
+  return main;
+}
+
+AbstractThread*
+DispatcherTrait::AbstractMainThreadFor(TaskCategory aCategory)
+{
+  // Return non DocGroup version by default.
+  return AbstractThread::MainThread();
+}

dom/base/DispatcherTrait.h

@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_DispatcherTrait_h
+#define mozilla_dom_DispatcherTrait_h
+
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/TaskCategory.h"
+
+class nsIEventTarget;
+class nsIRunnable;
+
+namespace mozilla {
+class AbstractThread;
+namespace dom {
+class TabGroup;
+
+// This trait should be attached to classes like nsIGlobalObject and nsIDocument
+// that have a DocGroup or TabGroup attached to them. The methods here should
+// delegate to the DocGroup or TabGroup. We can't use the Dispatcher class
+// directly because it inherits from nsISupports.
+class DispatcherTrait {
+public:
+  // This method may or may not be safe off of the main thread. For nsIDocument
+  // it is safe. For nsIGlobalWindow it is not safe.
+  virtual nsresult Dispatch(const char* aName,
+                            TaskCategory aCategory,
+                            already_AddRefed<nsIRunnable>&& aRunnable);
+
+  // This method may or may not be safe off of the main thread. For nsIDocument
+  // it is safe. For nsIGlobalWindow it is not safe. The nsIEventTarget can
+  // always be used off the main thread.
+  virtual nsIEventTarget* EventTargetFor(TaskCategory aCategory) const;
+
+  // Must be called on the main thread. The AbstractThread can always be used
+  // off the main thread.
+  virtual AbstractThread* AbstractMainThreadFor(TaskCategory aCategory);
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // mozilla_dom_DispatcherTrait_h

dom/base/DocGroup.cpp

@@ -49,8 +49,6 @@ DocGroup::~DocGroup()
   mTabGroup->mDocGroups.RemoveEntry(mKey);
 }
 
-NS_IMPL_ISUPPORTS(DocGroup, nsISupports)
-
 nsresult
 DocGroup::Dispatch(const char* aName,
                    TaskCategory aCategory,
@@ -66,7 +64,7 @@ DocGroup::EventTargetFor(TaskCategory aCategory) const
 }
 
 AbstractThread*
-DocGroup::AbstractMainThreadFor(TaskCategory aCategory)
+DocGroup::AbstractMainThreadForImpl(TaskCategory aCategory)
 {
   MOZ_RELEASE_ASSERT(NS_IsMainThread());
   return mTabGroup->AbstractMainThreadFor(aCategory);

dom/base/DocGroup.h

@@ -7,13 +7,12 @@
 #ifndef DocGroup_h
 #define DocGroup_h
 
-#include "nsISupports.h"
 #include "nsISupportsImpl.h"
 #include "nsIPrincipal.h"
 #include "nsTHashtable.h"
 #include "nsString.h"
 
-#include "mozilla/dom/Dispatcher.h"
+#include "mozilla/Dispatcher.h"
 #include "mozilla/RefPtr.h"
 
 namespace mozilla {
@@ -43,7 +42,7 @@ public:
   typedef nsTArray<nsIDocument*>::iterator Iterator;
   friend class TabGroup;
 
-  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(DocGroup, override)
 
   // Returns NS_ERROR_FAILURE and sets |aString| to an empty string if the TLD
   // service isn't available. Returns NS_OK on success, but may still set
@@ -77,10 +76,10 @@ public:
 
   virtual nsIEventTarget* EventTargetFor(TaskCategory aCategory) const override;
 
-  virtual AbstractThread*
-  AbstractMainThreadFor(TaskCategory aCategory) override;
-
 private:
+  virtual AbstractThread*
+  AbstractMainThreadForImpl(TaskCategory aCategory) override;
+
   DocGroup(TabGroup* aTabGroup, const nsACString& aKey);
   ~DocGroup();
 

dom/base/TabGroup.cpp

@@ -243,8 +243,6 @@ TabGroup::GetTopLevelWindows()
   return array;
 }
 
-NS_IMPL_ISUPPORTS(TabGroup, nsISupports)
-
 TabGroup::HashEntry::HashEntry(const nsACString* aKey)
   : nsCStringHashKey(aKey), mDocGroup(nullptr)
 {}
@@ -286,7 +284,7 @@ TabGroup::EventTargetFor(TaskCategory aCategory) const
 }
 
 AbstractThread*
-TabGroup::AbstractMainThreadFor(TaskCategory aCategory)
+TabGroup::AbstractMainThreadForImpl(TaskCategory aCategory)
 {
   MOZ_RELEASE_ASSERT(NS_IsMainThread());
   MOZ_ASSERT(aCategory != TaskCategory::Count);

dom/base/TabGroup.h

@@ -7,14 +7,13 @@
 #ifndef TabGroup_h
 #define TabGroup_h
 
-#include "nsISupports.h"
 #include "nsISupportsImpl.h"
 #include "nsIPrincipal.h"
 #include "nsTHashtable.h"
 #include "nsString.h"
 
 #include "mozilla/Atomics.h"
-#include "mozilla/dom/Dispatcher.h"
+#include "mozilla/Dispatcher.h"
 #include "mozilla/RefPtr.h"
 
 namespace mozilla {
@@ -57,7 +56,7 @@ public:
 
   friend class DocGroup;
 
-  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(TabGroup, override)
 
   static TabGroup*
   GetChromeTabGroup();
@@ -122,10 +121,10 @@ public:
 
   TabGroup* AsTabGroup() override { return this; }
 
-  virtual AbstractThread*
-  AbstractMainThreadFor(TaskCategory aCategory) override;
-
 private:
+  virtual AbstractThread*
+  AbstractMainThreadForImpl(TaskCategory aCategory) override;
+
   void EnsureThrottledEventQueues();
 
   ~TabGroup();

dom/base/moz.build

@@ -154,7 +154,7 @@ EXPORTS.mozilla.dom += [
     'Comment.h',
     'CustomElementRegistry.h',
     'DirectionalityUtils.h',
-    'Dispatcher.h',
+    'DispatcherTrait.h',
     'DocGroup.h',
     'DocumentFragment.h',
     'DocumentType.h',
@@ -226,7 +226,7 @@ UNIFIED_SOURCES += [
     'Crypto.cpp',
     'CustomElementRegistry.cpp',
     'DirectionalityUtils.cpp',
-    'Dispatcher.cpp',
+    'DispatcherTrait.cpp',
     'DocGroup.cpp',
     'DocumentFragment.cpp',
     'DocumentType.cpp',

dom/base/nsIDocument.h

@@ -32,7 +32,7 @@
 #include "nsClassHashtable.h"
 #include "prclist.h"
 #include "mozilla/CORSMode.h"
-#include "mozilla/dom/Dispatcher.h"
+#include "mozilla/dom/DispatcherTrait.h"
 #include "mozilla/LinkedList.h"
 #include "mozilla/StyleBackendType.h"
 #include "mozilla/StyleSheet.h"

dom/base/nsIGlobalObject.h

@@ -7,7 +7,7 @@
 #ifndef nsIGlobalObject_h__
 #define nsIGlobalObject_h__
 
-#include "mozilla/dom/Dispatcher.h"
+#include "mozilla/dom/DispatcherTrait.h"
 #include "nsISupports.h"
 #include "nsTArray.h"
 #include "js/TypeDecls.h"

dom/base/nsPIDOMWindow.h

@@ -12,8 +12,8 @@
 
 #include "nsCOMPtr.h"
 #include "nsTArray.h"
-#include "mozilla/dom/Dispatcher.h"
 #include "mozilla/dom/EventTarget.h"
+#include "mozilla/TaskCategory.h"
 #include "js/TypeDecls.h"
 #include "nsRefPtrHashtable.h"
 
@@ -29,6 +29,7 @@ class nsICSSDeclaration;
 class nsIDocShell;
 class nsIDocShellLoadInfo;
 class nsIDocument;
+class nsIEventTarget;
 class nsIIdleObserver;
 class nsIPrincipal;
 class nsIScriptTimeoutHandler;

xpcom/threads/Dispatcher.cpp

@@ -4,7 +4,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#include "mozilla/dom/Dispatcher.h"
+#include "mozilla/Dispatcher.h"
 
 #include "mozilla/AbstractThread.h"
 #include "mozilla/Move.h"
@@ -13,38 +13,6 @@
 
 using namespace mozilla;
 
-nsresult
-DispatcherTrait::Dispatch(const char* aName,
-                          TaskCategory aCategory,
-                          already_AddRefed<nsIRunnable>&& aRunnable)
-{
-  nsCOMPtr<nsIRunnable> runnable(aRunnable);
-  if (aName) {
-    if (nsCOMPtr<nsINamed> named = do_QueryInterface(runnable)) {
-      named->SetName(aName);
-    }
-  }
-  if (NS_IsMainThread()) {
-    return NS_DispatchToCurrentThread(runnable.forget());
-  } else {
-    return NS_DispatchToMainThread(runnable.forget());
-  }
-}
-
-nsIEventTarget*
-DispatcherTrait::EventTargetFor(TaskCategory aCategory) const
-{
-  nsCOMPtr<nsIEventTarget> main = do_GetMainThread();
-  return main;
-}
-
-AbstractThread*
-DispatcherTrait::AbstractMainThreadFor(TaskCategory aCategory)
-{
-  // Return non DocGroup version by default.
-  return AbstractThread::MainThread();
-}
-
 namespace {
 
 #define NS_DISPATCHEREVENTTARGET_IID \
@@ -53,13 +21,13 @@ namespace {
 
 class DispatcherEventTarget final : public nsIEventTarget
 {
-  RefPtr<dom::Dispatcher> mDispatcher;
+  RefPtr<Dispatcher> mDispatcher;
   TaskCategory mCategory;
 
 public:
   NS_DECLARE_STATIC_IID_ACCESSOR(NS_DISPATCHEREVENTTARGET_IID)
 
-  DispatcherEventTarget(dom::Dispatcher* aDispatcher, TaskCategory aCategory)
+  DispatcherEventTarget(Dispatcher* aDispatcher, TaskCategory aCategory)
    : mDispatcher(aDispatcher)
    , mCategory(aCategory)
   {}
@@ -67,10 +35,10 @@ public:
   NS_DECL_THREADSAFE_ISUPPORTS
   NS_DECL_NSIEVENTTARGET
 
-  dom::Dispatcher* Dispatcher() const { return mDispatcher; }
+  Dispatcher* Dispatcher() const { return mDispatcher; }
 
 private:
-  virtual ~DispatcherEventTarget() {}
+  ~DispatcherEventTarget() {}
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(DispatcherEventTarget, NS_DISPATCHEREVENTTARGET_IID)
@@ -107,6 +75,13 @@ DispatcherEventTarget::IsOnCurrentThread(bool* aIsOnCurrentThread)
   return NS_OK;
 }
 
+AbstractThread*
+Dispatcher::AbstractMainThreadFor(TaskCategory aCategory)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  return AbstractMainThreadForImpl(aCategory);
+}
+
 already_AddRefed<nsIEventTarget>
 Dispatcher::CreateEventTargetFor(TaskCategory aCategory)
 {

xpcom/threads/Dispatcher.h

@@ -0,0 +1,70 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_Dispatcher_h
+#define mozilla_Dispatcher_h
+
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/TaskCategory.h"
+#include "nsISupportsImpl.h"
+
+class nsIEventTarget;
+class nsIRunnable;
+
+namespace mozilla {
+class AbstractThread;
+namespace dom {
+class TabGroup;
+}
+
+// The "main thread" in Gecko will soon be a set of cooperatively scheduled
+// "fibers". Global state in Gecko will be partitioned into a series of "groups"
+// (with roughly one group per tab). Runnables will be annotated with the set of
+// groups that they touch. Two runnables may run concurrently on different
+// fibers as long as they touch different groups.
+//
+// A Dispatcher is an abstract class to represent a "group". Essentially the
+// only functionality offered by a Dispatcher is the ability to dispatch
+// runnables to the group. TabGroup, DocGroup, and SystemGroup are the concrete
+// implementations of Dispatcher.
+class Dispatcher {
+public:
+  NS_INLINE_DECL_PURE_VIRTUAL_REFCOUNTING
+
+  // Implementations of this method must be safe to call off the main thread.
+  virtual nsresult Dispatch(const char* aName,
+                            TaskCategory aCategory,
+                            already_AddRefed<nsIRunnable>&& aRunnable) = 0;
+
+  // Implementations of this method must be safe to call off the main thread.
+  // The returned nsIEventTarget must also be usable from any thread.
+  virtual nsIEventTarget* EventTargetFor(TaskCategory aCategory) const = 0;
+
+  // Must always be called on the main thread. The returned AbstractThread can
+  // always be used off the main thread.
+  AbstractThread* AbstractMainThreadFor(TaskCategory aCategory);
+
+  // This method performs a safe cast. It returns null if |this| is not of the
+  // requested type.
+  virtual dom::TabGroup* AsTabGroup() { return nullptr; }
+
+protected:
+  // Implementations are guaranteed that this method is called on the main
+  // thread.
+  virtual AbstractThread* AbstractMainThreadForImpl(TaskCategory aCategory) = 0;
+
+  // Helper method to create an event target specific to a particular TaskCategory.
+  virtual already_AddRefed<nsIEventTarget>
+  CreateEventTargetFor(TaskCategory aCategory);
+
+  // Given an event target returned by |dispatcher->CreateEventTargetFor|, this
+  // function returns |dispatcher|.
+  static Dispatcher* FromEventTarget(nsIEventTarget* aEventTarget);
+};
+
+} // namespace mozilla
+
+#endif // mozilla_dom_Dispatcher_h

xpcom/threads/moz.build

@@ -39,6 +39,7 @@ EXPORTS.mozilla += [
     'BlockingResourceBase.h',
     'CondVar.h',
     'DeadlockDetector.h',
+    'Dispatcher.h',
     'HangAnnotations.h',
     'HangMonitor.h',
     'LazyIdleThread.h',
@@ -62,6 +63,7 @@ UNIFIED_SOURCES += [
     'AbstractThread.cpp',
     'BackgroundHangMonitor.cpp',
     'BlockingResourceBase.cpp',
+    'Dispatcher.cpp',
     'HangAnnotations.cpp',
     'HangMonitor.cpp',
     'LazyIdleThread.cpp',