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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /xpcom/threads/nsThreadManager.cpp
parentInitial commit. (diff)
downloadfirefox-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 'xpcom/threads/nsThreadManager.cpp')
-rw-r--r--xpcom/threads/nsThreadManager.cpp798
1 files changed, 798 insertions, 0 deletions
diff --git a/xpcom/threads/nsThreadManager.cpp b/xpcom/threads/nsThreadManager.cpp
new file mode 100644
index 0000000000..367b520a54
--- /dev/null
+++ b/xpcom/threads/nsThreadManager.cpp
@@ -0,0 +1,798 @@
+/* -*- 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 "nsThreadManager.h"
+#include "nsThread.h"
+#include "nsThreadPool.h"
+#include "nsThreadUtils.h"
+#include "nsIClassInfoImpl.h"
+#include "nsExceptionHandler.h"
+#include "nsTArray.h"
+#include "nsXULAppAPI.h"
+#include "nsExceptionHandler.h"
+#include "mozilla/AbstractThread.h"
+#include "mozilla/AppShutdown.h"
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/CycleCollectedJSContext.h" // nsAutoMicroTask
+#include "mozilla/EventQueue.h"
+#include "mozilla/InputTaskManager.h"
+#include "mozilla/Mutex.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/ProfilerMarkers.h"
+#include "mozilla/SpinEventLoopUntil.h"
+#include "mozilla/StaticPtr.h"
+#include "mozilla/TaskQueue.h"
+#include "mozilla/ThreadEventQueue.h"
+#include "mozilla/ThreadLocal.h"
+#include "TaskController.h"
+#include "ThreadEventTarget.h"
+#ifdef MOZ_CANARY
+# include <fcntl.h>
+# include <unistd.h>
+#endif
+
+#include "MainThreadIdlePeriod.h"
+
+using namespace mozilla;
+
+static MOZ_THREAD_LOCAL(bool) sTLSIsMainThread;
+
+bool NS_IsMainThreadTLSInitialized() { return sTLSIsMainThread.initialized(); }
+
+class BackgroundEventTarget final : public nsIEventTarget,
+ public TaskQueueTracker {
+ public:
+ NS_DECL_THREADSAFE_ISUPPORTS
+ NS_DECL_NSIEVENTTARGET_FULL
+
+ BackgroundEventTarget() = default;
+
+ nsresult Init();
+
+ already_AddRefed<nsISerialEventTarget> CreateBackgroundTaskQueue(
+ const char* aName);
+
+ void BeginShutdown(nsTArray<RefPtr<ShutdownPromise>>&);
+ void FinishShutdown();
+
+ private:
+ ~BackgroundEventTarget() = default;
+
+ nsCOMPtr<nsIThreadPool> mPool;
+ nsCOMPtr<nsIThreadPool> mIOPool;
+};
+
+NS_IMPL_ISUPPORTS(BackgroundEventTarget, nsIEventTarget, TaskQueueTracker)
+
+nsresult BackgroundEventTarget::Init() {
+ nsCOMPtr<nsIThreadPool> pool(new nsThreadPool());
+ NS_ENSURE_TRUE(pool, NS_ERROR_FAILURE);
+
+ nsresult rv = pool->SetName("BackgroundThreadPool"_ns);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ // Use potentially more conservative stack size.
+ rv = pool->SetThreadStackSize(nsIThreadManager::kThreadPoolStackSize);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ // Thread limit of 2 makes deadlock during synchronous dispatch less likely.
+ rv = pool->SetThreadLimit(2);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ rv = pool->SetIdleThreadLimit(1);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ // Leave threads alive for up to 5 minutes
+ rv = pool->SetIdleThreadTimeout(300000);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ // Initialize the background I/O event target.
+ nsCOMPtr<nsIThreadPool> ioPool(new nsThreadPool());
+ NS_ENSURE_TRUE(pool, NS_ERROR_FAILURE);
+
+ // The io pool spends a lot of its time blocking on io, so we want to offload
+ // these jobs on a lower priority if available.
+ rv = ioPool->SetQoSForThreads(nsIThread::QOS_PRIORITY_LOW);
+ NS_ENSURE_SUCCESS(
+ rv, rv); // note: currently infallible, keeping this for brevity.
+
+ rv = ioPool->SetName("BgIOThreadPool"_ns);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ // Use potentially more conservative stack size.
+ rv = ioPool->SetThreadStackSize(nsIThreadManager::kThreadPoolStackSize);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ // Thread limit of 4 makes deadlock during synchronous dispatch less likely.
+ rv = ioPool->SetThreadLimit(4);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ rv = ioPool->SetIdleThreadLimit(1);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ // Leave threads alive for up to 5 minutes
+ rv = ioPool->SetIdleThreadTimeout(300000);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ pool.swap(mPool);
+ ioPool.swap(mIOPool);
+
+ return NS_OK;
+}
+
+NS_IMETHODIMP_(bool)
+BackgroundEventTarget::IsOnCurrentThreadInfallible() {
+ return mPool->IsOnCurrentThread() || mIOPool->IsOnCurrentThread();
+}
+
+NS_IMETHODIMP
+BackgroundEventTarget::IsOnCurrentThread(bool* aValue) {
+ bool value = false;
+ if (NS_SUCCEEDED(mPool->IsOnCurrentThread(&value)) && value) {
+ *aValue = value;
+ return NS_OK;
+ }
+ return mIOPool->IsOnCurrentThread(aValue);
+}
+
+NS_IMETHODIMP
+BackgroundEventTarget::Dispatch(already_AddRefed<nsIRunnable> aRunnable,
+ uint32_t aFlags) {
+ // We need to be careful here, because if an event is getting dispatched here
+ // from within TaskQueue::Runner::Run, it will be dispatched with
+ // NS_DISPATCH_AT_END, but we might not be running the event on the same
+ // pool, depending on which pool we were on and the dispatch flags. If we
+ // dispatch an event with NS_DISPATCH_AT_END to the wrong pool, the pool
+ // may not process the event in a timely fashion, which can lead to deadlock.
+ uint32_t flags = aFlags & ~NS_DISPATCH_EVENT_MAY_BLOCK;
+ bool mayBlock = bool(aFlags & NS_DISPATCH_EVENT_MAY_BLOCK);
+ nsCOMPtr<nsIThreadPool>& pool = mayBlock ? mIOPool : mPool;
+
+ // If we're already running on the pool we want to dispatch to, we can
+ // unconditionally add NS_DISPATCH_AT_END to indicate that we shouldn't spin
+ // up a new thread.
+ //
+ // Otherwise, we should remove NS_DISPATCH_AT_END so we don't run into issues
+ // like those in the above comment.
+ if (pool->IsOnCurrentThread()) {
+ flags |= NS_DISPATCH_AT_END;
+ } else {
+ flags &= ~NS_DISPATCH_AT_END;
+ }
+
+ return pool->Dispatch(std::move(aRunnable), flags);
+}
+
+NS_IMETHODIMP
+BackgroundEventTarget::DispatchFromScript(nsIRunnable* aRunnable,
+ uint32_t aFlags) {
+ nsCOMPtr<nsIRunnable> runnable(aRunnable);
+ return Dispatch(runnable.forget(), aFlags);
+}
+
+NS_IMETHODIMP
+BackgroundEventTarget::DelayedDispatch(already_AddRefed<nsIRunnable> aRunnable,
+ uint32_t) {
+ nsCOMPtr<nsIRunnable> dropRunnable(aRunnable);
+ return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+BackgroundEventTarget::RegisterShutdownTask(nsITargetShutdownTask* aTask) {
+ return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+BackgroundEventTarget::UnregisterShutdownTask(nsITargetShutdownTask* aTask) {
+ return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+void BackgroundEventTarget::BeginShutdown(
+ nsTArray<RefPtr<ShutdownPromise>>& promises) {
+ auto queues = GetAllTrackedTaskQueues();
+ for (auto& queue : queues) {
+ promises.AppendElement(queue->BeginShutdown());
+ }
+}
+
+void BackgroundEventTarget::FinishShutdown() {
+ mPool->Shutdown();
+ mIOPool->Shutdown();
+}
+
+already_AddRefed<nsISerialEventTarget>
+BackgroundEventTarget::CreateBackgroundTaskQueue(const char* aName) {
+ return TaskQueue::Create(do_AddRef(this), aName).forget();
+}
+
+extern "C" {
+// This uses the C language linkage because it's exposed to Rust
+// via the xpcom/rust/moz_task crate.
+bool NS_IsMainThread() { return sTLSIsMainThread.get(); }
+}
+
+void NS_SetMainThread() {
+ if (!sTLSIsMainThread.init()) {
+ MOZ_CRASH();
+ }
+ sTLSIsMainThread.set(true);
+ MOZ_ASSERT(NS_IsMainThread());
+ // We initialize the SerialEventTargetGuard's TLS here for simplicity as it
+ // needs to be initialized around the same time you would initialize
+ // sTLSIsMainThread.
+ SerialEventTargetGuard::InitTLS();
+ nsThreadPool::InitTLS();
+}
+
+#ifdef DEBUG
+
+namespace mozilla {
+
+void AssertIsOnMainThread() { MOZ_ASSERT(NS_IsMainThread(), "Wrong thread!"); }
+
+} // namespace mozilla
+
+#endif
+
+typedef nsTArray<NotNull<RefPtr<nsThread>>> nsThreadArray;
+
+//-----------------------------------------------------------------------------
+
+/* static */
+void nsThreadManager::ReleaseThread(void* aData) {
+ static_cast<nsThread*>(aData)->Release();
+}
+
+// statically allocated instance
+NS_IMETHODIMP_(MozExternalRefCountType)
+nsThreadManager::AddRef() { return 2; }
+NS_IMETHODIMP_(MozExternalRefCountType)
+nsThreadManager::Release() { return 1; }
+NS_IMPL_CLASSINFO(nsThreadManager, nullptr,
+ nsIClassInfo::THREADSAFE | nsIClassInfo::SINGLETON,
+ NS_THREADMANAGER_CID)
+NS_IMPL_QUERY_INTERFACE_CI(nsThreadManager, nsIThreadManager)
+NS_IMPL_CI_INTERFACE_GETTER(nsThreadManager, nsIThreadManager)
+
+//-----------------------------------------------------------------------------
+
+/*static*/ nsThreadManager& nsThreadManager::get() {
+ static nsThreadManager sInstance;
+ return sInstance;
+}
+
+nsThreadManager::nsThreadManager()
+ : mCurThreadIndex(0), mMainPRThread(nullptr), mInitialized(false) {}
+
+nsThreadManager::~nsThreadManager() = default;
+
+nsresult nsThreadManager::Init() {
+ // Child processes need to initialize the thread manager before they
+ // initialize XPCOM in order to set up the crash reporter. This leads to
+ // situations where we get initialized twice.
+ if (mInitialized) {
+ return NS_OK;
+ }
+
+ if (PR_NewThreadPrivateIndex(&mCurThreadIndex, ReleaseThread) == PR_FAILURE) {
+ return NS_ERROR_FAILURE;
+ }
+
+#ifdef MOZ_CANARY
+ const int flags = O_WRONLY | O_APPEND | O_CREAT | O_NONBLOCK;
+ const mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
+ char* env_var_flag = getenv("MOZ_KILL_CANARIES");
+ sCanaryOutputFD =
+ env_var_flag
+ ? (env_var_flag[0] ? open(env_var_flag, flags, mode) : STDERR_FILENO)
+ : 0;
+#endif
+
+ TaskController::Initialize();
+
+ // Initialize idle handling.
+ nsCOMPtr<nsIIdlePeriod> idlePeriod = new MainThreadIdlePeriod();
+ TaskController::Get()->SetIdleTaskManager(
+ new IdleTaskManager(idlePeriod.forget()));
+
+ // Create main thread queue that forwards events to TaskController and
+ // construct main thread.
+ UniquePtr<EventQueue> queue = MakeUnique<EventQueue>(true);
+
+ RefPtr<ThreadEventQueue> synchronizedQueue =
+ new ThreadEventQueue(std::move(queue), true);
+
+ mMainThread = new nsThread(WrapNotNull(synchronizedQueue),
+ nsThread::MAIN_THREAD, {.stackSize = 0});
+
+ nsresult rv = mMainThread->InitCurrentThread();
+ if (NS_FAILED(rv)) {
+ mMainThread = nullptr;
+ return rv;
+ }
+
+ // We need to keep a pointer to the current thread, so we can satisfy
+ // GetIsMainThread calls that occur post-Shutdown.
+ mMainThread->GetPRThread(&mMainPRThread);
+
+ // Init AbstractThread.
+ AbstractThread::InitTLS();
+ AbstractThread::InitMainThread();
+
+ // Initialize the background event target.
+ RefPtr<BackgroundEventTarget> target(new BackgroundEventTarget());
+
+ rv = target->Init();
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ mBackgroundEventTarget = std::move(target);
+
+ mInitialized = true;
+
+ return NS_OK;
+}
+
+void nsThreadManager::ShutdownNonMainThreads() {
+ MOZ_ASSERT(NS_IsMainThread(), "shutdown not called from main thread");
+
+ // Prevent further access to the thread manager (no more new threads!)
+ //
+ // What happens if shutdown happens before NewThread completes?
+ // We Shutdown() the new thread, and return error if we've started Shutdown
+ // between when NewThread started, and when the thread finished initializing
+ // and registering with ThreadManager.
+ //
+ mInitialized = false;
+
+ // Empty the main thread event queue before we begin shutting down threads.
+ NS_ProcessPendingEvents(mMainThread);
+
+ mMainThread->mEvents->RunShutdownTasks();
+
+ nsTArray<RefPtr<ShutdownPromise>> promises;
+ mBackgroundEventTarget->BeginShutdown(promises);
+
+ bool taskQueuesShutdown = false;
+ // It's fine to capture everything by reference in the Then handler since it
+ // runs before we exit the nested event loop, thanks to the SpinEventLoopUntil
+ // below.
+ ShutdownPromise::All(mMainThread, promises)->Then(mMainThread, __func__, [&] {
+ mBackgroundEventTarget->FinishShutdown();
+ taskQueuesShutdown = true;
+ });
+
+ // Wait for task queues to shutdown, so we don't shut down the underlying
+ // threads of the background event target in the block below, thereby
+ // preventing the task queues from emptying, preventing the shutdown promises
+ // from resolving, and prevent anything checking `taskQueuesShutdown` from
+ // working.
+ mozilla::SpinEventLoopUntil(
+ "nsThreadManager::Shutdown"_ns, [&]() { return taskQueuesShutdown; },
+ mMainThread);
+
+ {
+ // We gather the threads into a list, so that we avoid holding the
+ // enumerator lock while calling nsIThread::Shutdown.
+ nsTArray<RefPtr<nsThread>> threadsToShutdown;
+ for (auto* thread : nsThread::Enumerate()) {
+ if (thread->ShutdownRequired()) {
+ threadsToShutdown.AppendElement(thread);
+ }
+ }
+
+ // It's tempting to walk the list of threads here and tell them each to stop
+ // accepting new events, but that could lead to badness if one of those
+ // threads is stuck waiting for a response from another thread. To do it
+ // right, we'd need some way to interrupt the threads.
+ //
+ // Instead, we process events on the current thread while waiting for
+ // threads to shutdown. This means that we have to preserve a mostly
+ // functioning world until such time as the threads exit.
+
+ // Shutdown all threads that require it (join with threads that we created).
+ for (auto& thread : threadsToShutdown) {
+ thread->Shutdown();
+ }
+ }
+
+ // NB: It's possible that there are events in the queue that want to *start*
+ // an asynchronous shutdown. But we have already shutdown the threads above,
+ // so there's no need to worry about them. We only have to wait for all
+ // in-flight asynchronous thread shutdowns to complete.
+ mMainThread->WaitForAllAsynchronousShutdowns();
+
+ // There are no more background threads at this point.
+}
+
+void nsThreadManager::ShutdownMainThread() {
+ MOZ_ASSERT(!mInitialized, "Must have called BeginShutdown");
+
+ // Do NS_ProcessPendingEvents but with special handling to set
+ // mEventsAreDoomed atomically with the removal of the last event. This means
+ // that PutEvent cannot succeed if the event would be left in the main thread
+ // queue after our final call to NS_ProcessPendingEvents.
+ // See comments in `nsThread::ThreadFunc` for a more detailed explanation.
+ while (true) {
+ if (mMainThread->mEvents->ShutdownIfNoPendingEvents()) {
+ break;
+ }
+ NS_ProcessPendingEvents(mMainThread);
+ }
+
+ // Normally thread shutdown clears the observer for the thread, but since the
+ // main thread is special we do it manually here after we're sure all events
+ // have been processed.
+ mMainThread->SetObserver(nullptr);
+
+ mBackgroundEventTarget = nullptr;
+}
+
+void nsThreadManager::ReleaseMainThread() {
+ MOZ_ASSERT(!mInitialized, "Must have called BeginShutdown");
+ MOZ_ASSERT(!mBackgroundEventTarget, "Must have called ShutdownMainThread");
+ MOZ_ASSERT(mMainThread);
+
+ // Release main thread object.
+ mMainThread = nullptr;
+
+ // Remove the TLS entry for the main thread.
+ PR_SetThreadPrivate(mCurThreadIndex, nullptr);
+}
+
+void nsThreadManager::RegisterCurrentThread(nsThread& aThread) {
+ MOZ_ASSERT(aThread.GetPRThread() == PR_GetCurrentThread(), "bad aThread");
+
+ aThread.AddRef(); // for TLS entry
+ PR_SetThreadPrivate(mCurThreadIndex, &aThread);
+}
+
+void nsThreadManager::UnregisterCurrentThread(nsThread& aThread) {
+ MOZ_ASSERT(aThread.GetPRThread() == PR_GetCurrentThread(), "bad aThread");
+
+ PR_SetThreadPrivate(mCurThreadIndex, nullptr);
+ // Ref-count balanced via ReleaseThread
+}
+
+nsThread* nsThreadManager::CreateCurrentThread(
+ SynchronizedEventQueue* aQueue, nsThread::MainThreadFlag aMainThread) {
+ // Make sure we don't have an nsThread yet.
+ MOZ_ASSERT(!PR_GetThreadPrivate(mCurThreadIndex));
+
+ if (!mInitialized) {
+ return nullptr;
+ }
+
+ RefPtr<nsThread> thread =
+ new nsThread(WrapNotNull(aQueue), aMainThread, {.stackSize = 0});
+ if (!thread || NS_FAILED(thread->InitCurrentThread())) {
+ return nullptr;
+ }
+
+ return thread.get(); // reference held in TLS
+}
+
+nsresult nsThreadManager::DispatchToBackgroundThread(nsIRunnable* aEvent,
+ uint32_t aDispatchFlags) {
+ if (!mInitialized) {
+ return NS_ERROR_FAILURE;
+ }
+
+ nsCOMPtr<nsIEventTarget> backgroundTarget(mBackgroundEventTarget);
+ return backgroundTarget->Dispatch(aEvent, aDispatchFlags);
+}
+
+already_AddRefed<nsISerialEventTarget>
+nsThreadManager::CreateBackgroundTaskQueue(const char* aName) {
+ if (!mInitialized) {
+ return nullptr;
+ }
+
+ return mBackgroundEventTarget->CreateBackgroundTaskQueue(aName);
+}
+
+nsThread* nsThreadManager::GetCurrentThread() {
+ // read thread local storage
+ void* data = PR_GetThreadPrivate(mCurThreadIndex);
+ if (data) {
+ return static_cast<nsThread*>(data);
+ }
+
+ if (!mInitialized) {
+ return nullptr;
+ }
+
+ // OK, that's fine. We'll dynamically create one :-)
+ //
+ // We assume that if we're implicitly creating a thread here that it doesn't
+ // want an event queue. Any thread which wants an event queue should
+ // explicitly create its nsThread wrapper.
+ RefPtr<nsThread> thread = new nsThread();
+ if (!thread || NS_FAILED(thread->InitCurrentThread())) {
+ return nullptr;
+ }
+
+ return thread.get(); // reference held in TLS
+}
+
+bool nsThreadManager::IsNSThread() const {
+ if (!mInitialized) {
+ return false;
+ }
+ if (auto* thread = (nsThread*)PR_GetThreadPrivate(mCurThreadIndex)) {
+ return thread->EventQueue();
+ }
+ return false;
+}
+
+NS_IMETHODIMP
+nsThreadManager::NewNamedThread(
+ const nsACString& aName, nsIThreadManager::ThreadCreationOptions aOptions,
+ nsIThread** aResult) {
+ // Note: can be called from arbitrary threads
+
+ // No new threads during Shutdown
+ if (NS_WARN_IF(!mInitialized)) {
+ return NS_ERROR_NOT_INITIALIZED;
+ }
+
+ [[maybe_unused]] TimeStamp startTime = TimeStamp::Now();
+
+ RefPtr<ThreadEventQueue> queue =
+ new ThreadEventQueue(MakeUnique<EventQueue>());
+ RefPtr<nsThread> thr =
+ new nsThread(WrapNotNull(queue), nsThread::NOT_MAIN_THREAD, aOptions);
+ nsresult rv =
+ thr->Init(aName); // Note: blocks until the new thread has been set up
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ // At this point, we expect that the thread has been registered in
+ // mThreadByPRThread; however, it is possible that it could have also been
+ // replaced by now, so we cannot really assert that it was added. Instead,
+ // kill it if we entered Shutdown() during/before Init()
+
+ if (NS_WARN_IF(!mInitialized)) {
+ if (thr->ShutdownRequired()) {
+ thr->Shutdown(); // ok if it happens multiple times
+ }
+ return NS_ERROR_NOT_INITIALIZED;
+ }
+
+ PROFILER_MARKER_TEXT(
+ "NewThread", OTHER,
+ MarkerOptions(MarkerStack::Capture(),
+ MarkerTiming::IntervalUntilNowFrom(startTime)),
+ aName);
+ if (!NS_IsMainThread()) {
+ PROFILER_MARKER_TEXT(
+ "NewThread (non-main thread)", OTHER,
+ MarkerOptions(MarkerStack::Capture(), MarkerThreadId::MainThread(),
+ MarkerTiming::IntervalUntilNowFrom(startTime)),
+ aName);
+ }
+
+ thr.forget(aResult);
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsThreadManager::GetMainThread(nsIThread** aResult) {
+ // Keep this functioning during Shutdown
+ if (!mMainThread) {
+ if (!NS_IsMainThread()) {
+ NS_WARNING(
+ "Called GetMainThread but there isn't a main thread and "
+ "we're not the main thread.");
+ }
+ return NS_ERROR_NOT_INITIALIZED;
+ }
+ NS_ADDREF(*aResult = mMainThread);
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsThreadManager::GetCurrentThread(nsIThread** aResult) {
+ // Keep this functioning during Shutdown
+ if (!mMainThread) {
+ return NS_ERROR_NOT_INITIALIZED;
+ }
+ *aResult = GetCurrentThread();
+ if (!*aResult) {
+ return NS_ERROR_OUT_OF_MEMORY;
+ }
+ NS_ADDREF(*aResult);
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsThreadManager::SpinEventLoopUntil(const nsACString& aVeryGoodReasonToDoThis,
+ nsINestedEventLoopCondition* aCondition) {
+ return SpinEventLoopUntilInternal(aVeryGoodReasonToDoThis, aCondition,
+ ShutdownPhase::NotInShutdown);
+}
+
+NS_IMETHODIMP
+nsThreadManager::SpinEventLoopUntilOrQuit(
+ const nsACString& aVeryGoodReasonToDoThis,
+ nsINestedEventLoopCondition* aCondition) {
+ return SpinEventLoopUntilInternal(aVeryGoodReasonToDoThis, aCondition,
+ ShutdownPhase::AppShutdownConfirmed);
+}
+
+// statics from SpinEventLoopUntil.h
+AutoNestedEventLoopAnnotation* AutoNestedEventLoopAnnotation::sCurrent =
+ nullptr;
+StaticMutex AutoNestedEventLoopAnnotation::sStackMutex;
+
+// static from SpinEventLoopUntil.h
+void AutoNestedEventLoopAnnotation::AnnotateXPCOMSpinEventLoopStack(
+ const nsACString& aStack) {
+ if (aStack.Length() > 0) {
+ nsCString prefixedStack(XRE_GetProcessTypeString());
+ prefixedStack += ": "_ns + aStack;
+ CrashReporter::AnnotateCrashReport(
+ CrashReporter::Annotation::XPCOMSpinEventLoopStack, prefixedStack);
+ } else {
+ CrashReporter::AnnotateCrashReport(
+ CrashReporter::Annotation::XPCOMSpinEventLoopStack, ""_ns);
+ }
+}
+
+nsresult nsThreadManager::SpinEventLoopUntilInternal(
+ const nsACString& aVeryGoodReasonToDoThis,
+ nsINestedEventLoopCondition* aCondition,
+ ShutdownPhase aShutdownPhaseToCheck) {
+ // XXX: We would want to AssertIsOnMainThread(); but that breaks some GTest.
+ nsCOMPtr<nsINestedEventLoopCondition> condition(aCondition);
+ nsresult rv = NS_OK;
+
+ if (!mozilla::SpinEventLoopUntil(aVeryGoodReasonToDoThis, [&]() -> bool {
+ // Check if an ongoing shutdown reached our limits.
+ if (aShutdownPhaseToCheck > ShutdownPhase::NotInShutdown &&
+ AppShutdown::GetCurrentShutdownPhase() >= aShutdownPhaseToCheck) {
+ return true;
+ }
+
+ bool isDone = false;
+ rv = condition->IsDone(&isDone);
+ // JS failure should be unusual, but we need to stop and propagate
+ // the error back to the caller.
+ if (NS_FAILED(rv)) {
+ return true;
+ }
+
+ return isDone;
+ })) {
+ // We stopped early for some reason, which is unexpected.
+ return NS_ERROR_UNEXPECTED;
+ }
+
+ // If we exited when the condition told us to, we need to return whether
+ // the condition encountered failure when executing.
+ return rv;
+}
+
+NS_IMETHODIMP
+nsThreadManager::SpinEventLoopUntilEmpty() {
+ nsIThread* thread = NS_GetCurrentThread();
+
+ while (NS_HasPendingEvents(thread)) {
+ (void)NS_ProcessNextEvent(thread, false);
+ }
+
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsThreadManager::GetMainThreadEventTarget(nsIEventTarget** aTarget) {
+ nsCOMPtr<nsIEventTarget> target = GetMainThreadSerialEventTarget();
+ target.forget(aTarget);
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsThreadManager::DispatchToMainThread(nsIRunnable* aEvent, uint32_t aPriority,
+ uint8_t aArgc) {
+ // Note: C++ callers should instead use NS_DispatchToMainThread.
+ MOZ_ASSERT(NS_IsMainThread());
+
+ // Keep this functioning during Shutdown
+ if (NS_WARN_IF(!mMainThread)) {
+ return NS_ERROR_NOT_INITIALIZED;
+ }
+ // If aPriority wasn't explicitly passed, that means it should be treated as
+ // PRIORITY_NORMAL.
+ if (aArgc > 0 && aPriority != nsIRunnablePriority::PRIORITY_NORMAL) {
+ nsCOMPtr<nsIRunnable> event(aEvent);
+ return mMainThread->DispatchFromScript(
+ new PrioritizableRunnable(event.forget(), aPriority), 0);
+ }
+ return mMainThread->DispatchFromScript(aEvent, 0);
+}
+
+class AutoMicroTaskWrapperRunnable final : public Runnable {
+ public:
+ explicit AutoMicroTaskWrapperRunnable(nsIRunnable* aEvent)
+ : Runnable("AutoMicroTaskWrapperRunnable"), mEvent(aEvent) {
+ MOZ_ASSERT(aEvent);
+ }
+
+ private:
+ ~AutoMicroTaskWrapperRunnable() = default;
+
+ NS_IMETHOD Run() override {
+ nsAutoMicroTask mt;
+
+ return mEvent->Run();
+ }
+
+ RefPtr<nsIRunnable> mEvent;
+};
+
+NS_IMETHODIMP
+nsThreadManager::DispatchToMainThreadWithMicroTask(nsIRunnable* aEvent,
+ uint32_t aPriority,
+ uint8_t aArgc) {
+ RefPtr<AutoMicroTaskWrapperRunnable> runnable =
+ new AutoMicroTaskWrapperRunnable(aEvent);
+
+ return DispatchToMainThread(runnable, aPriority, aArgc);
+}
+
+void nsThreadManager::EnableMainThreadEventPrioritization() {
+ MOZ_ASSERT(NS_IsMainThread());
+ InputTaskManager::Get()->EnableInputEventPrioritization();
+}
+
+void nsThreadManager::FlushInputEventPrioritization() {
+ MOZ_ASSERT(NS_IsMainThread());
+ InputTaskManager::Get()->FlushInputEventPrioritization();
+}
+
+void nsThreadManager::SuspendInputEventPrioritization() {
+ MOZ_ASSERT(NS_IsMainThread());
+ InputTaskManager::Get()->SuspendInputEventPrioritization();
+}
+
+void nsThreadManager::ResumeInputEventPrioritization() {
+ MOZ_ASSERT(NS_IsMainThread());
+ InputTaskManager::Get()->ResumeInputEventPrioritization();
+}
+
+// static
+bool nsThreadManager::MainThreadHasPendingHighPriorityEvents() {
+ MOZ_ASSERT(NS_IsMainThread());
+ bool retVal = false;
+ if (get().mMainThread) {
+ get().mMainThread->HasPendingHighPriorityEvents(&retVal);
+ }
+ return retVal;
+}
+
+NS_IMETHODIMP
+nsThreadManager::IdleDispatchToMainThread(nsIRunnable* aEvent,
+ uint32_t aTimeout) {
+ // Note: C++ callers should instead use NS_DispatchToThreadQueue or
+ // NS_DispatchToCurrentThreadQueue.
+ MOZ_ASSERT(NS_IsMainThread());
+
+ nsCOMPtr<nsIRunnable> event(aEvent);
+ if (aTimeout) {
+ return NS_DispatchToThreadQueue(event.forget(), aTimeout, mMainThread,
+ EventQueuePriority::Idle);
+ }
+
+ return NS_DispatchToThreadQueue(event.forget(), mMainThread,
+ EventQueuePriority::Idle);
+}
+
+NS_IMETHODIMP
+nsThreadManager::DispatchDirectTaskToCurrentThread(nsIRunnable* aEvent) {
+ NS_ENSURE_STATE(aEvent);
+ nsCOMPtr<nsIRunnable> runnable = aEvent;
+ return GetCurrentThread()->DispatchDirectTask(runnable.forget());
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-04 14:49:54 +0000