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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
#ifndef mozilla_EventQueue_h
#define mozilla_EventQueue_h
#include "mozilla/Mutex.h"
#include "mozilla/Queue.h"
#include "mozilla/TimeStamp.h"
#include "nsCOMPtr.h"
#include "nsIRunnable.h"
namespace mozilla {
#define EVENT_QUEUE_PRIORITY_LIST(EVENT_PRIORITY) \
EVENT_PRIORITY(Idle, 0) \
EVENT_PRIORITY(DeferredTimers, 1) \
EVENT_PRIORITY(Low, 2) \
EVENT_PRIORITY(InputLow, 3) \
EVENT_PRIORITY(Normal, 4) \
EVENT_PRIORITY(MediumHigh, 5) \
EVENT_PRIORITY(InputHigh, 6) \
EVENT_PRIORITY(Vsync, 7) \
EVENT_PRIORITY(InputHighest, 8) \
EVENT_PRIORITY(RenderBlocking, 9) \
EVENT_PRIORITY(Control, 10)
enum class EventQueuePriority {
#define EVENT_PRIORITY(NAME, VALUE) NAME = VALUE,
EVENT_QUEUE_PRIORITY_LIST(EVENT_PRIORITY)
#undef EVENT_PRIORITY
Invalid
};
class IdlePeriodState;
namespace detail {
// EventQueue is our unsynchronized event queue implementation. It is a queue
// of runnables used for non-main thread, as well as optionally providing
// forwarding to TaskController.
//
// Since EventQueue is unsynchronized, it should be wrapped in an outer
// SynchronizedEventQueue implementation (like ThreadEventQueue).
template <size_t ItemsPerPage>
class EventQueueInternal {
public:
explicit EventQueueInternal(bool aForwardToTC) : mForwardToTC(aForwardToTC) {}
// Add an event to the end of the queue. Implementors are free to use
// aPriority however they wish. If the runnable supports
// nsIRunnablePriority and the implementing class supports
// prioritization, aPriority represents the result of calling
// nsIRunnablePriority::GetPriority(). *aDelay is time the event has
// already been delayed (used when moving an event from one queue to
// another)
void PutEvent(already_AddRefed<nsIRunnable>&& aEvent,
EventQueuePriority aPriority, const MutexAutoLock& aProofOfLock,
mozilla::TimeDuration* aDelay = nullptr);
// Get an event from the front of the queue. This should return null if the
// queue is non-empty but the event in front is not ready to run.
// *aLastEventDelay is the time the event spent in queues before being
// retrieved.
already_AddRefed<nsIRunnable> GetEvent(
const MutexAutoLock& aProofOfLock,
mozilla::TimeDuration* aLastEventDelay = nullptr);
// Returns true if the queue is empty. Implies !HasReadyEvent().
bool IsEmpty(const MutexAutoLock& aProofOfLock);
// Returns true if the queue is non-empty and if the event in front is ready
// to run. Implies !IsEmpty(). This should return true iff GetEvent returns a
// non-null value.
bool HasReadyEvent(const MutexAutoLock& aProofOfLock);
// Returns the number of events in the queue.
size_t Count(const MutexAutoLock& aProofOfLock) const;
// For some reason, if we put this in the .cpp file the linker can't find it
already_AddRefed<nsIRunnable> PeekEvent(const MutexAutoLock& aProofOfLock) {
if (mQueue.IsEmpty()) {
return nullptr;
}
nsCOMPtr<nsIRunnable> result = mQueue.FirstElement();
return result.forget();
}
void EnableInputEventPrioritization(const MutexAutoLock& aProofOfLock) {}
void FlushInputEventPrioritization(const MutexAutoLock& aProofOfLock) {}
void SuspendInputEventPrioritization(const MutexAutoLock& aProofOfLock) {}
void ResumeInputEventPrioritization(const MutexAutoLock& aProofOfLock) {}
size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
size_t size = mQueue.ShallowSizeOfExcludingThis(aMallocSizeOf);
size += mDispatchTimes.ShallowSizeOfExcludingThis(aMallocSizeOf);
return size;
}
private:
mozilla::Queue<nsCOMPtr<nsIRunnable>, ItemsPerPage> mQueue;
// This queue is only populated when the profiler is turned on.
mozilla::Queue<mozilla::TimeStamp, ItemsPerPage> mDispatchTimes;
TimeDuration mLastEventDelay;
// This indicates PutEvent forwards runnables to the TaskController. This
// should be true for the top level event queue on the main thread.
bool mForwardToTC;
};
} // namespace detail
class EventQueue final : public mozilla::detail::EventQueueInternal<16> {
public:
explicit EventQueue(bool aForwardToTC = false)
: mozilla::detail::EventQueueInternal<16>(aForwardToTC) {}
};
template <size_t ItemsPerPage = 16>
class EventQueueSized final
: public mozilla::detail::EventQueueInternal<ItemsPerPage> {
public:
explicit EventQueueSized(bool aForwardToTC = false)
: mozilla::detail::EventQueueInternal<ItemsPerPage>(aForwardToTC) {}
};
} // namespace mozilla
#endif // mozilla_EventQueue_h