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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /widget/android/AndroidUiThread.cpp | |
parent | Initial commit. (diff) | |
download | firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'widget/android/AndroidUiThread.cpp')
-rw-r--r-- | widget/android/AndroidUiThread.cpp | 377 |
1 files changed, 377 insertions, 0 deletions
diff --git a/widget/android/AndroidUiThread.cpp b/widget/android/AndroidUiThread.cpp new file mode 100644 index 0000000000..dc8d56b163 --- /dev/null +++ b/widget/android/AndroidUiThread.cpp @@ -0,0 +1,377 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* 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 "base/message_loop.h" +#include "mozilla/Atomics.h" +#include "mozilla/EventQueue.h" +#include "mozilla/java/GeckoThreadWrappers.h" +#include "mozilla/LinkedList.h" +#include "mozilla/Monitor.h" +#include "mozilla/Mutex.h" +#include "mozilla/RefPtr.h" +#include "mozilla/ScopeExit.h" +#include "mozilla/StaticPtr.h" +#include "mozilla/ThreadEventQueue.h" +#include "mozilla/TimeStamp.h" +#include "mozilla/UniquePtr.h" +#include "GeckoProfiler.h" +#include "nsThread.h" +#include "nsThreadManager.h" +#include "nsThreadUtils.h" + +#include <android/api-level.h> +#include <pthread.h> + +using namespace mozilla; + +namespace { + +class AndroidUiThread; +class AndroidUiTask; + +StaticAutoPtr<LinkedList<AndroidUiTask> > sTaskQueue; +StaticAutoPtr<mozilla::Mutex> sTaskQueueLock; +StaticRefPtr<AndroidUiThread> sThread; +static bool sThreadDestroyed; +static MessageLoop* sMessageLoop; +static Atomic<Monitor*> sMessageLoopAccessMonitor; + +void EnqueueTask(already_AddRefed<nsIRunnable> aTask, int aDelayMs); + +/* + * The AndroidUiThread is derived from nsThread so that nsIRunnable objects that + * get dispatched may be intercepted. Only nsIRunnable objects that need to be + * synchronously executed are passed into the nsThread to be queued. All other + * nsIRunnable object are immediately dispatched to the Android UI thread. + * AndroidUiThread is derived from nsThread instead of being an nsIEventTarget + * wrapper that contains an nsThread object because if nsIRunnable objects with + * a delay were dispatch directly to an nsThread object, such as obtained from + * nsThreadManager::GetCurrentThread(), the nsIRunnable could get stuck in the + * nsThread nsIRunnable queue. This is due to the fact that Android controls the + * event loop in the Android UI thread and has no knowledge of when the nsThread + * needs to be drained. + */ + +class AndroidUiThread : public nsThread { + public: + NS_INLINE_DECL_REFCOUNTING_INHERITED(AndroidUiThread, nsThread) + AndroidUiThread() + : nsThread( + MakeNotNull<ThreadEventQueue*>(MakeUnique<mozilla::EventQueue>()), + nsThread::NOT_MAIN_THREAD, {.stackSize = 0}) {} + + nsresult Dispatch(already_AddRefed<nsIRunnable> aEvent, + uint32_t aFlags) override; + nsresult DelayedDispatch(already_AddRefed<nsIRunnable> aEvent, + uint32_t aDelayMs) override; + + private: + ~AndroidUiThread() {} +}; + +NS_IMETHODIMP +AndroidUiThread::Dispatch(already_AddRefed<nsIRunnable> aEvent, + uint32_t aFlags) { + EnqueueTask(std::move(aEvent), 0); + return NS_OK; +} + +NS_IMETHODIMP +AndroidUiThread::DelayedDispatch(already_AddRefed<nsIRunnable> aEvent, + uint32_t aDelayMs) { + EnqueueTask(std::move(aEvent), aDelayMs); + return NS_OK; +} + +static void PumpEvents() { NS_ProcessPendingEvents(sThread.get()); } + +class ThreadObserver : public nsIThreadObserver { + public: + NS_DECL_THREADSAFE_ISUPPORTS + NS_DECL_NSITHREADOBSERVER + + ThreadObserver() {} + + private: + virtual ~ThreadObserver() {} +}; + +NS_IMPL_ISUPPORTS(ThreadObserver, nsIThreadObserver) + +NS_IMETHODIMP +ThreadObserver::OnDispatchedEvent() { + EnqueueTask(NS_NewRunnableFunction("PumpEvents", &PumpEvents), 0); + return NS_OK; +} + +NS_IMETHODIMP +ThreadObserver::OnProcessNextEvent(nsIThreadInternal* thread, bool mayWait) { + return NS_OK; +} + +NS_IMETHODIMP +ThreadObserver::AfterProcessNextEvent(nsIThreadInternal* thread, + bool eventWasProcessed) { + return NS_OK; +} + +class AndroidUiTask : public LinkedListElement<AndroidUiTask> { + using TimeStamp = mozilla::TimeStamp; + using TimeDuration = mozilla::TimeDuration; + + public: + explicit AndroidUiTask(already_AddRefed<nsIRunnable> aTask) + : mTask(aTask), + mRunTime() // Null timestamp representing no delay. + {} + + AndroidUiTask(already_AddRefed<nsIRunnable> aTask, int aDelayMs) + : mTask(aTask), + mRunTime(TimeStamp::Now() + TimeDuration::FromMilliseconds(aDelayMs)) {} + + bool IsEarlierThan(const AndroidUiTask& aOther) const { + if (mRunTime) { + return aOther.mRunTime ? mRunTime < aOther.mRunTime : false; + } + // In the case of no delay, we're earlier if aOther has a delay. + // Otherwise, we're not earlier, to maintain task order. + return !!aOther.mRunTime; + } + + int64_t MillisecondsToRunTime() const { + if (mRunTime) { + return int64_t((mRunTime - TimeStamp::Now()).ToMilliseconds()); + } + return 0; + } + + already_AddRefed<nsIRunnable> TakeTask() { return mTask.forget(); } + + private: + nsCOMPtr<nsIRunnable> mTask; + const TimeStamp mRunTime; +}; + +class CreateOnUiThread : public Runnable { + public: + CreateOnUiThread() : Runnable("CreateOnUiThread") {} + + NS_IMETHOD Run() override { + MOZ_ASSERT(!sThreadDestroyed); + MOZ_ASSERT(sMessageLoopAccessMonitor); + MonitorAutoLock lock(*sMessageLoopAccessMonitor); + sThread = new AndroidUiThread(); + sThread->InitCurrentThread(); + sThread->SetObserver(new ThreadObserver()); + RegisterThreadWithProfiler(); + sMessageLoop = + new MessageLoop(MessageLoop::TYPE_MOZILLA_ANDROID_UI, sThread.get()); + lock.NotifyAll(); + return NS_OK; + } + + private: + static void RegisterThreadWithProfiler() { +#if defined(MOZ_GECKO_PROFILER) + // We don't use the PROFILER_REGISTER_THREAD macro here because by this + // point the Android UI thread is already quite a ways into its stack; + // the profiler's sampler thread will ignore a lot of frames if we do not + // provide a better value for the stack top. We'll manually obtain that + // info via pthreads. + + // Fallback address if any pthread calls fail + char fallback; + char* stackTop = &fallback; + + auto regOnExit = MakeScopeExit( + [&stackTop]() { profiler_register_thread("AndroidUI", stackTop); }); + + // Bionic does not properly support pthread_attr_getstack for the UI thread + // until Lollipop (API 21). +# if __ANDROID_API__ >= __ANDROID_API_L__ + pthread_attr_t attrs; + if (pthread_getattr_np(pthread_self(), &attrs)) { + return; + } + + void* stackBase; + size_t stackSize; + if (pthread_attr_getstack(&attrs, &stackBase, &stackSize)) { + return; + } + + stackTop = static_cast<char*>(stackBase) + stackSize - 1; +# endif // __ANDROID_API__ >= __ANDROID_API_L__ +#endif // defined(MOZ_GECKO_PROFILER) + } +}; + +class DestroyOnUiThread : public Runnable { + public: + DestroyOnUiThread() : Runnable("DestroyOnUiThread"), mDestroyed(false) {} + + NS_IMETHOD Run() override { + MOZ_ASSERT(!sThreadDestroyed); + MOZ_ASSERT(sMessageLoopAccessMonitor); + MOZ_ASSERT(sTaskQueue); + MonitorAutoLock lock(*sMessageLoopAccessMonitor); + sThreadDestroyed = true; + + { + // Flush the queue + MutexAutoLock lock(*sTaskQueueLock); + while (AndroidUiTask* task = sTaskQueue->getFirst()) { + delete task; + } + } + + delete sMessageLoop; + sMessageLoop = nullptr; + MOZ_ASSERT(sThread); + PROFILER_UNREGISTER_THREAD(); + nsThreadManager::get().UnregisterCurrentThread(*sThread); + sThread = nullptr; + mDestroyed = true; + lock.NotifyAll(); + return NS_OK; + } + + void WaitForDestruction() { + MOZ_ASSERT(sMessageLoopAccessMonitor); + MonitorAutoLock lock(*sMessageLoopAccessMonitor); + while (!mDestroyed) { + lock.Wait(); + } + } + + private: + bool mDestroyed; +}; + +void EnqueueTask(already_AddRefed<nsIRunnable> aTask, int aDelayMs) { + if (sThreadDestroyed) { + return; + } + + // add the new task into the sTaskQueue, sorted with + // the earliest task first in the queue + AndroidUiTask* newTask = + (aDelayMs ? new AndroidUiTask(std::move(aTask), aDelayMs) + : new AndroidUiTask(std::move(aTask))); + + bool headOfList = false; + { + MOZ_ASSERT(sTaskQueue); + MOZ_ASSERT(sTaskQueueLock); + MutexAutoLock lock(*sTaskQueueLock); + + AndroidUiTask* task = sTaskQueue->getFirst(); + + while (task) { + if (newTask->IsEarlierThan(*task)) { + task->setPrevious(newTask); + break; + } + task = task->getNext(); + } + + if (!newTask->isInList()) { + sTaskQueue->insertBack(newTask); + } + headOfList = !newTask->getPrevious(); + } + + if (headOfList) { + // if we're inserting it at the head of the queue, notify Java because + // we need to get a callback at an earlier time than the last scheduled + // callback + java::GeckoThread::RequestUiThreadCallback(int64_t(aDelayMs)); + } +} + +} // namespace + +namespace mozilla { + +void CreateAndroidUiThread() { + MOZ_ASSERT(!sThread); + MOZ_ASSERT(!sMessageLoopAccessMonitor); + sTaskQueue = new LinkedList<AndroidUiTask>(); + sTaskQueueLock = new Mutex("AndroidUiThreadTaskQueueLock"); + sMessageLoopAccessMonitor = + new Monitor("AndroidUiThreadMessageLoopAccessMonitor"); + sThreadDestroyed = false; + RefPtr<CreateOnUiThread> runnable = new CreateOnUiThread; + EnqueueTask(do_AddRef(runnable), 0); +} + +void DestroyAndroidUiThread() { + MOZ_ASSERT(sThread); + RefPtr<DestroyOnUiThread> runnable = new DestroyOnUiThread; + EnqueueTask(do_AddRef(runnable), 0); + runnable->WaitForDestruction(); + delete sMessageLoopAccessMonitor; + sMessageLoopAccessMonitor = nullptr; +} + +MessageLoop* GetAndroidUiThreadMessageLoop() { + if (!sMessageLoopAccessMonitor) { + return nullptr; + } + + MonitorAutoLock lock(*sMessageLoopAccessMonitor); + while (!sMessageLoop) { + lock.Wait(); + } + + return sMessageLoop; +} + +RefPtr<nsThread> GetAndroidUiThread() { + if (!sMessageLoopAccessMonitor) { + return nullptr; + } + + MonitorAutoLock lock(*sMessageLoopAccessMonitor); + while (!sThread) { + lock.Wait(); + } + + return sThread; +} + +int64_t RunAndroidUiTasks() { + MutexAutoLock lock(*sTaskQueueLock); + + if (sThreadDestroyed) { + return -1; + } + + while (!sTaskQueue->isEmpty()) { + AndroidUiTask* task = sTaskQueue->getFirst(); + const int64_t timeLeft = task->MillisecondsToRunTime(); + if (timeLeft > 0) { + // this task (and therefore all remaining tasks) + // have not yet reached their runtime. return the + // time left until we should be called again + return timeLeft; + } + + // Retrieve task before unlocking/running. + nsCOMPtr<nsIRunnable> runnable(task->TakeTask()); + // LinkedListElements auto remove from list upon destruction + delete task; + + // Unlock to allow posting new tasks reentrantly. + MutexAutoUnlock unlock(*sTaskQueueLock); + runnable->Run(); + if (sThreadDestroyed) { + return -1; + } + } + return -1; +} + +} // namespace mozilla |