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/* -*- 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 "nsTArray.h"
#include "nsXULAppAPI.h"
#include "mozilla/AbstractThread.h"
#include "mozilla/AppShutdown.h"
#include "mozilla/ClearOnShutdown.h"
#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"
#ifdef MOZ_CANARY
# include <fcntl.h>
# include <unistd.h>
#endif
#include "MainThreadIdlePeriod.h"
#include "InputEventStatistics.h"
using namespace mozilla;
static MOZ_THREAD_LOCAL(bool) sTLSIsMainThread;
bool NS_IsMainThreadTLSInitialized() { return sTLSIsMainThread.initialized(); }
class BackgroundEventTarget final : public nsIEventTarget {
public:
NS_DECL_THREADSAFE_ISUPPORTS
NS_DECL_NSIEVENTTARGET_FULL
BackgroundEventTarget();
nsresult Init();
already_AddRefed<nsISerialEventTarget> CreateBackgroundTaskQueue(
const char* aName);
using CancelPromise = TaskQueue::CancelPromise::AllPromiseType;
RefPtr<CancelPromise> CancelBackgroundDelayedRunnables();
void BeginShutdown(nsTArray<RefPtr<ShutdownPromise>>&);
void FinishShutdown();
private:
~BackgroundEventTarget() = default;
nsCOMPtr<nsIThreadPool> mPool;
nsCOMPtr<nsIThreadPool> mIOPool;
Mutex mMutex;
nsTArray<RefPtr<TaskQueue>> mTaskQueues;
bool mIsBackgroundDelayedRunnablesCanceled;
};
NS_IMPL_ISUPPORTS(BackgroundEventTarget, nsIEventTarget)
BackgroundEventTarget::BackgroundEventTarget()
: mMutex("BackgroundEventTarget::mMutex") {}
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);
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;
}
void BackgroundEventTarget::BeginShutdown(
nsTArray<RefPtr<ShutdownPromise>>& promises) {
for (auto& queue : mTaskQueues) {
promises.AppendElement(queue->BeginShutdown());
}
}
void BackgroundEventTarget::FinishShutdown() {
mPool->Shutdown();
mIOPool->Shutdown();
}
already_AddRefed<nsISerialEventTarget>
BackgroundEventTarget::CreateBackgroundTaskQueue(const char* aName) {
MutexAutoLock lock(mMutex);
RefPtr<TaskQueue> queue = new TaskQueue(do_AddRef(this), aName);
mTaskQueues.AppendElement(queue);
return queue.forget();
}
auto BackgroundEventTarget::CancelBackgroundDelayedRunnables()
-> RefPtr<CancelPromise> {
MOZ_ASSERT(NS_IsMainThread());
MutexAutoLock lock(mMutex);
mIsBackgroundDelayedRunnablesCanceled = true;
nsTArray<RefPtr<TaskQueue::CancelPromise>> promises;
for (const auto& tq : mTaskQueues) {
promises.AppendElement(tq->CancelDelayedRunnables());
}
return TaskQueue::CancelPromise::All(GetMainThreadSerialEventTarget(),
promises);
}
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();
}
#ifdef DEBUG
namespace mozilla {
void AssertIsOnMainThread() { MOZ_ASSERT(NS_IsMainThread(), "Wrong thread!"); }
} // namespace mozilla
#endif
typedef nsTArray<NotNull<RefPtr<nsThread>>> nsThreadArray;
static Atomic<bool> sShutdownComplete;
//-----------------------------------------------------------------------------
/* static */
void nsThreadManager::ReleaseThread(void* aData) {
if (sShutdownComplete) {
// We've already completed shutdown and released the references to all or
// our TLS wrappers. Don't try to release them again.
return;
}
auto* thread = static_cast<nsThread*>(aData);
if (thread->mHasTLSEntry) {
thread->mHasTLSEntry = false;
thread->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, 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::Shutdown() {
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);
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.
::SpinEventLoopUntil([&]() { return taskQueuesShutdown; }, mMainThread);
{
// We gather the threads from the hashtable 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();
mMainThread->mEventTarget->NotifyShutdown();
// In case there are any more events somehow...
NS_ProcessPendingEvents(mMainThread);
// There are no more background threads at this point.
// 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;
// Release main thread object.
mMainThread = nullptr;
// Remove the TLS entry for the main thread.
PR_SetThreadPrivate(mCurThreadIndex, nullptr);
{
// Cleanup the last references to any threads which haven't shut down yet.
nsTArray<RefPtr<nsThread>> threads;
for (auto* thread : nsThread::Enumerate()) {
if (thread->mHasTLSEntry) {
threads.AppendElement(dont_AddRef(thread));
thread->mHasTLSEntry = false;
}
}
}
// xpcshell tests sometimes leak the main thread. They don't enable leak
// checking, so that doesn't cause the test to fail, but leaving the entry in
// the thread list triggers an assertion, which does.
nsThread::ClearThreadList();
sShutdownComplete = true;
}
void nsThreadManager::RegisterCurrentThread(nsThread& aThread) {
MOZ_ASSERT(aThread.GetPRThread() == PR_GetCurrentThread(), "bad aThread");
aThread.AddRef(); // for TLS entry
aThread.mHasTLSEntry = true;
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, 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);
}
void nsThreadManager::CancelBackgroundDelayedRunnables() {
if (!mInitialized) {
return;
}
bool canceled = false;
mBackgroundEventTarget->CancelBackgroundDelayedRunnables()->Then(
GetMainThreadSerialEventTarget(), __func__, [&] { canceled = true; });
::SpinEventLoopUntil([&]() { return canceled; });
}
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, uint32_t aStackSize,
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, aStackSize);
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);
}
struct MOZ_STACK_CLASS AutoNestedEventLoopAnnotation {
explicit AutoNestedEventLoopAnnotation(const nsACString& aEntry)
: mPrev(sCurrent) {
sCurrent = this;
if (mPrev) {
mStack = mPrev->mStack + "|"_ns + aEntry;
} else {
mStack = aEntry;
}
CrashReporter::AnnotateCrashReport(
CrashReporter::Annotation::XPCOMSpinEventLoopStack, mStack);
}
~AutoNestedEventLoopAnnotation() {
MOZ_ASSERT(sCurrent == this);
sCurrent = mPrev;
if (mPrev) {
CrashReporter::AnnotateCrashReport(
CrashReporter::Annotation::XPCOMSpinEventLoopStack, mPrev->mStack);
} else {
CrashReporter::RemoveCrashReportAnnotation(
CrashReporter::Annotation::XPCOMSpinEventLoopStack);
}
}
private:
AutoNestedEventLoopAnnotation(const AutoNestedEventLoopAnnotation&) = delete;
AutoNestedEventLoopAnnotation& operator=(
const AutoNestedEventLoopAnnotation&) = delete;
static AutoNestedEventLoopAnnotation* sCurrent;
AutoNestedEventLoopAnnotation* mPrev;
nsCString mStack;
};
AutoNestedEventLoopAnnotation* AutoNestedEventLoopAnnotation::sCurrent =
nullptr;
nsresult nsThreadManager::SpinEventLoopUntilInternal(
const nsACString& aVeryGoodReasonToDoThis,
nsINestedEventLoopCondition* aCondition,
ShutdownPhase aCheckingShutdownPhase) {
AutoNestedEventLoopAnnotation annotation(aVeryGoodReasonToDoThis);
AUTO_PROFILER_LABEL_DYNAMIC_NSCSTRING_NONSENSITIVE(
"nsThreadManager::SpinEventLoop", OTHER, aVeryGoodReasonToDoThis);
AUTO_PROFILER_MARKER_TEXT("SpinEventLoop", OTHER, MarkerStack::Capture(),
aVeryGoodReasonToDoThis);
// XXX: We would want to AssertIsOnMainThread(); but that breaks some GTest.
nsCOMPtr<nsINestedEventLoopCondition> condition(aCondition);
nsresult rv = NS_OK;
bool checkingShutdown =
(aCheckingShutdownPhase > ShutdownPhase::NotInShutdown);
// Nothing to do if already shutting down.
if (checkingShutdown &&
AppShutdown::GetCurrentShutdownPhase() >= aCheckingShutdownPhase) {
return NS_OK;
}
if (!mozilla::SpinEventLoopUntil([&]() -> bool {
// Check if shutting down reached our limits.
if (checkingShutdown &&
AppShutdown::GetCurrentShutdownPhase() >= aCheckingShutdownPhase) {
// This will make us return with NS_OK.
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);
}
void nsThreadManager::EnableMainThreadEventPrioritization() {
MOZ_ASSERT(NS_IsMainThread());
InputEventStatistics::Get().SetEnable(true);
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);
}