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| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
| commit | 26a029d407be480d791972afb5975cf62c9360a6 (patch) | |
| tree | f435a8308119effd964b339f76abb83a57c29483 /xpcom/threads/nsThreadManager.h | |
| parent | Initial commit. (diff) | |
| download | firefox-e51783d008170d9ab27d25da98ca3a38b0a41b67.tar.xz firefox-e51783d008170d9ab27d25da98ca3a38b0a41b67.zip | |
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'xpcom/threads/nsThreadManager.h')
| -rw-r--r-- | xpcom/threads/nsThreadManager.h | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/xpcom/threads/nsThreadManager.h b/xpcom/threads/nsThreadManager.h new file mode 100644 index 0000000000..46e061a1ad --- /dev/null +++ b/xpcom/threads/nsThreadManager.h @@ -0,0 +1,156 @@ +/* -*- 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 nsThreadManager_h__ +#define nsThreadManager_h__ + +#include "nsIThreadManager.h" +#include "nsThread.h" +#include "mozilla/ShutdownPhase.h" + +class nsIRunnable; +class nsIThread; + +namespace mozilla { +class IdleTaskManager; +class SynchronizedEventQueue; +class TaskQueue; + +template <typename T> +class NeverDestroyed; +} // namespace mozilla + +class BackgroundEventTarget; + +class nsThreadManager : public nsIThreadManager { + public: + NS_DECL_ISUPPORTS + NS_DECL_NSITHREADMANAGER + + static nsThreadManager& get(); + + nsresult Init(); + + // Shutdown all threads other than the main thread. This function should only + // be called on the main thread of the application process. + void ShutdownNonMainThreads(); + + // Finish shutting down all threads. This function must be called after + // ShutdownNonMainThreads and will delete the BackgroundEventTarget and + // take the main thread event target out of commission, but without + // releasing the underlying nsThread object. + void ShutdownMainThread(); + + // Release the underlying main thread nsThread object. + void ReleaseMainThread(); + + // Called by nsThread to inform the ThreadManager it exists. This method + // must be called when the given thread is the current thread. + void RegisterCurrentThread(nsThread& aThread); + + // Called by nsThread to inform the ThreadManager it is going away. This + // method must be called when the given thread is the current thread. + void UnregisterCurrentThread(nsThread& aThread); + + // Returns the current thread. Returns null if OOM or if ThreadManager isn't + // initialized. Creates the nsThread if one does not exist yet. + nsThread* GetCurrentThread(); + + // Returns true iff the currently running thread has an nsThread associated + // with it (ie; whether this is a thread that we can dispatch runnables to). + bool IsNSThread() const; + + // CreateCurrentThread sets up an nsThread for the current thread. It uses the + // event queue and main thread flags passed in. It should only be called once + // for the current thread. After it returns, GetCurrentThread() will return + // the thread that was created. GetCurrentThread() will also create a thread + // (lazily), but it doesn't allow the queue or main-thread attributes to be + // specified. + nsThread* CreateCurrentThread(mozilla::SynchronizedEventQueue* aQueue); + + nsresult DispatchToBackgroundThread(nsIRunnable* aEvent, + uint32_t aDispatchFlags); + + already_AddRefed<mozilla::TaskQueue> CreateBackgroundTaskQueue( + const char* aName); + + ~nsThreadManager(); + + void EnableMainThreadEventPrioritization(); + void FlushInputEventPrioritization(); + void SuspendInputEventPrioritization(); + void ResumeInputEventPrioritization(); + + static bool MainThreadHasPendingHighPriorityEvents(); + + nsIThread* GetMainThreadWeak() { return mMainThread; } + + // Low level methods for interacting with the global thread list. Be very + // careful when holding `ThreadListMutex()` as no new threads can be started + // while it is held. + mozilla::OffTheBooksMutex& ThreadListMutex() MOZ_RETURN_CAPABILITY(mMutex) { + return mMutex; + } + + bool AllowNewXPCOMThreads() MOZ_EXCLUDES(mMutex); + bool AllowNewXPCOMThreadsLocked() MOZ_REQUIRES(mMutex) { + return mState == State::eActive; + } + + mozilla::LinkedList<nsThread>& ThreadList() MOZ_REQUIRES(mMutex) { + return mThreadList; + } + + private: + friend class mozilla::NeverDestroyed<nsThreadManager>; + + nsThreadManager(); + + nsresult SpinEventLoopUntilInternal( + const nsACString& aVeryGoodReasonToDoThis, + nsINestedEventLoopCondition* aCondition, + mozilla::ShutdownPhase aShutdownPhaseToCheck); + + static void ReleaseThread(void* aData); + + enum class State : uint8_t { + // The thread manager has yet to be initialized. + eUninit, + // The thread manager is active, and operating normally. + eActive, + // The thread manager is in XPCOM shutdown. New calls to NS_NewNamedThread + // will fail, as all XPCOM threads are required to be shutting down. + eShutdown, + }; + + unsigned mCurThreadIndex; // thread-local-storage index + RefPtr<nsThread> mMainThread; + + mutable mozilla::OffTheBooksMutex mMutex; + + // Current state in the thread manager's lifecycle. See docs above. + State mState MOZ_GUARDED_BY(mMutex); + + // Global list of active nsThread instances, including both explicitly and + // implicitly created threads. + // + // NOTE: New entries to this list _may_ be added after mAllowNewThreads has + // been cleared, but only for implicitly created thread wrappers which are + // not shut down during XPCOM shutdown. + mozilla::LinkedList<nsThread> mThreadList MOZ_GUARDED_BY(mMutex); + + // Shared event target used for background runnables. + RefPtr<BackgroundEventTarget> mBackgroundEventTarget MOZ_GUARDED_BY(mMutex); +}; + +#define NS_THREADMANAGER_CID \ + { /* 7a4204c6-e45a-4c37-8ebb-6709a22c917c */ \ + 0x7a4204c6, 0xe45a, 0x4c37, { \ + 0x8e, 0xbb, 0x67, 0x09, 0xa2, 0x2c, 0x91, 0x7c \ + } \ + } + +#endif // nsThreadManager_h__ |