diff options
Diffstat (limited to 'layout/base/nsRefreshDriver.h')
| -rw-r--r-- | layout/base/nsRefreshDriver.h | 633 |
1 files changed, 633 insertions, 0 deletions
diff --git a/layout/base/nsRefreshDriver.h b/layout/base/nsRefreshDriver.h new file mode 100644 index 0000000000..cc181c1822 --- /dev/null +++ b/layout/base/nsRefreshDriver.h @@ -0,0 +1,633 @@ +/* -*- 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/. */ + +/* + * Code to notify things that animate before a refresh, at an appropriate + * refresh rate. (Perhaps temporary, until replaced by compositor.) + */ + +#ifndef nsRefreshDriver_h_ +#define nsRefreshDriver_h_ + +#include "mozilla/FlushType.h" +#include "mozilla/TimeStamp.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/Vector.h" +#include "mozilla/WeakPtr.h" +#include "nsTObserverArray.h" +#include "nsTArray.h" +#include "nsTHashtable.h" +#include "nsClassHashtable.h" +#include "nsHashKeys.h" +#include "nsRefreshObservers.h" +#include "nsThreadUtils.h" +#include "mozilla/Attributes.h" +#include "mozilla/Maybe.h" +#include "mozilla/dom/VisualViewport.h" +#include "mozilla/layers/TransactionIdAllocator.h" +#include "LayersTypes.h" + +#ifdef MOZ_GECKO_PROFILER +# include "mozilla/ProfileChunkedBuffer.h" +#endif + +class nsPresContext; + +class imgIRequest; +class nsIRunnable; + +namespace mozilla { +class AnimationEventDispatcher; +class PendingFullscreenEvent; +class PresShell; +class RefreshDriverTimer; +class Runnable; + +} // namespace mozilla + +class nsRefreshDriver final : public mozilla::layers::TransactionIdAllocator, + public nsARefreshObserver { + using Document = mozilla::dom::Document; + using TransactionId = mozilla::layers::TransactionId; + using VVPResizeEvent = + mozilla::dom::VisualViewport::VisualViewportResizeEvent; + using VVPScrollEvent = + mozilla::dom::VisualViewport::VisualViewportScrollEvent; + using LogPresShellObserver = mozilla::LogPresShellObserver; + + public: + explicit nsRefreshDriver(nsPresContext* aPresContext); + ~nsRefreshDriver(); + + /** + * Methods for testing, exposed via nsIDOMWindowUtils. See + * nsIDOMWindowUtils.advanceTimeAndRefresh for description. + */ + void AdvanceTimeAndRefresh(int64_t aMilliseconds); + void RestoreNormalRefresh(); + void DoTick(); + bool IsTestControllingRefreshesEnabled() const { + return mTestControllingRefreshes; + } + + /** + * Return the time of the most recent refresh. This is intended to be + * used by callers who want to start an animation now and want to know + * what time to consider the start of the animation. (This helps + * ensure that multiple animations started during the same event off + * the main event loop have the same start time.) + */ + mozilla::TimeStamp MostRecentRefresh(bool aEnsureTimerStarted = true) const; + + /** + * Add / remove refresh observers. + * RemoveRefreshObserver returns true if aObserver was found. + * + * The flush type affects: + * + the order in which the observers are notified (lowest flush + * type to highest, in order registered) + * + (in the future) which observers are suppressed when the display + * doesn't require current position data or isn't currently + * painting, and, correspondingly, which get notified when there + * is a flush during such suppression + * and it must be FlushType::Style, FlushType::Layout, or FlushType::Display. + * + * The refresh driver does NOT own a reference to these observers; + * they must remove themselves before they are destroyed. + * + * The observer will be called even if there is no other activity. + */ + void AddRefreshObserver(nsARefreshObserver* aObserver, + mozilla::FlushType aFlushType, + const char* aObserverDescription); + bool RemoveRefreshObserver(nsARefreshObserver* aObserver, + mozilla::FlushType aFlushType); + /** + * Add / remove an observer wants to know the time when the refresh driver + * updated the most recent refresh time due to its active timer changes. + */ + void AddTimerAdjustmentObserver(nsATimerAdjustmentObserver* aObserver); + void RemoveTimerAdjustmentObserver(nsATimerAdjustmentObserver* aObserver); + + void PostVisualViewportResizeEvent(VVPResizeEvent* aResizeEvent); + void DispatchVisualViewportResizeEvents(); + + void PostScrollEvent(mozilla::Runnable* aScrollEvent, bool aDelayed = false); + void DispatchScrollEvents(); + + void PostVisualViewportScrollEvent(VVPScrollEvent* aScrollEvent); + void DispatchVisualViewportScrollEvents(); + + /** + * Add an observer that will be called after each refresh. The caller + * must remove the observer before it is deleted. This does not trigger + * refresh driver ticks. + */ + void AddPostRefreshObserver(nsAPostRefreshObserver* aObserver); + void AddPostRefreshObserver(mozilla::OneShotPostRefreshObserver* aObserver) = + delete; + void RemovePostRefreshObserver(nsAPostRefreshObserver* aObserver); + void RemovePostRefreshObserver( + mozilla::OneShotPostRefreshObserver* aObserver) = delete; + + /** + * Add/Remove imgIRequest versions of observers. + * + * These are used for hooking into the refresh driver for + * controlling animated images. + * + * @note The refresh driver owns a reference to these listeners. + * + * @note Technically, imgIRequest objects are not nsARefreshObservers, but + * for controlling animated image repaint events, we subscribe the + * imgIRequests to the nsRefreshDriver for notification of paint events. + * + * @returns whether the operation succeeded, or void in the case of removal. + */ + bool AddImageRequest(imgIRequest* aRequest); + void RemoveImageRequest(imgIRequest* aRequest); + + /** + * Add / remove presshells which have pending resize event. + */ + void AddResizeEventFlushObserver(mozilla::PresShell* aPresShell, + bool aDelayed = false) { + MOZ_DIAGNOSTIC_ASSERT( + !mResizeEventFlushObservers.Contains(aPresShell) && + !mDelayedResizeEventFlushObservers.Contains(aPresShell), + "Double-adding resize event flush observer"); + if (aDelayed) { + mDelayedResizeEventFlushObservers.AppendElement(aPresShell); + } else { + mResizeEventFlushObservers.AppendElement(aPresShell); + EnsureTimerStarted(); + } + } + + void RemoveResizeEventFlushObserver(mozilla::PresShell* aPresShell) { + mResizeEventFlushObservers.RemoveElement(aPresShell); + mDelayedResizeEventFlushObservers.RemoveElement(aPresShell); + } + + /** + * Add / remove presshells that we should flush style and layout on + */ + void AddStyleFlushObserver(mozilla::PresShell* aPresShell) { + MOZ_DIAGNOSTIC_ASSERT(!mStyleFlushObservers.Contains(aPresShell), + "Double-adding style flush observer"); + LogPresShellObserver::LogDispatch(aPresShell, this); + mStyleFlushObservers.AppendElement(aPresShell); + EnsureTimerStarted(); + } + + void RemoveStyleFlushObserver(mozilla::PresShell* aPresShell) { + mStyleFlushObservers.RemoveElement(aPresShell); + } + void AddLayoutFlushObserver(mozilla::PresShell* aPresShell) { + MOZ_DIAGNOSTIC_ASSERT(!IsLayoutFlushObserver(aPresShell), + "Double-adding layout flush observer"); + LogPresShellObserver::LogDispatch(aPresShell, this); + mLayoutFlushObservers.AppendElement(aPresShell); + EnsureTimerStarted(); + } + void RemoveLayoutFlushObserver(mozilla::PresShell* aPresShell) { + mLayoutFlushObservers.RemoveElement(aPresShell); + } + + bool IsLayoutFlushObserver(mozilla::PresShell* aPresShell) { + return mLayoutFlushObservers.Contains(aPresShell); + } + + /** + * "Early Runner" runnables will be called as the first step when refresh + * driver tick is triggered. Runners shouldn't keep other objects alive, + * since it isn't guaranteed they will ever get called. + */ + void AddEarlyRunner(nsIRunnable* aRunnable) { + mEarlyRunners.AppendElement(aRunnable); + EnsureTimerStarted(); + } + + /** + * Remember whether our presshell's view manager needs a flush + */ + void ScheduleViewManagerFlush(); + void RevokeViewManagerFlush() { mViewManagerFlushIsPending = false; } + bool ViewManagerFlushIsPending() { return mViewManagerFlushIsPending; } + bool HasScheduleFlush() { return mHasScheduleFlush; } + void ClearHasScheduleFlush() { mHasScheduleFlush = false; } + + /** + * Add a document for which we have FrameRequestCallbacks + */ + void ScheduleFrameRequestCallbacks(Document* aDocument); + + /** + * Remove a document for which we have FrameRequestCallbacks + */ + void RevokeFrameRequestCallbacks(Document* aDocument); + + /** + * Queue a new fullscreen event to be dispatched in next tick before + * the style flush + */ + void ScheduleFullscreenEvent( + mozilla::UniquePtr<mozilla::PendingFullscreenEvent> aEvent); + + /** + * Cancel all pending fullscreen events scheduled by ScheduleFullscreenEvent + * which targets any node in aDocument. + */ + void CancelPendingFullscreenEvents(Document* aDocument); + + /** + * Queue new animation events to dispatch in next tick. + */ + void ScheduleAnimationEventDispatch( + mozilla::AnimationEventDispatcher* aDispatcher) { + NS_ASSERTION(!mAnimationEventFlushObservers.Contains(aDispatcher), + "Double-adding animation event flush observer"); + mAnimationEventFlushObservers.AppendElement(aDispatcher); + EnsureTimerStarted(); + } + + /** + * Cancel all pending animation events associated with |aDispatcher|. + */ + void CancelPendingAnimationEvents( + mozilla::AnimationEventDispatcher* aDispatcher); + + /** + * Schedule a frame visibility update "soon", subject to the heuristics and + * throttling we apply to visibility updates. + */ + void ScheduleFrameVisibilityUpdate() { mNeedToRecomputeVisibility = true; } + + /** + * Tell the refresh driver that it is done driving refreshes and + * should stop its timer and forget about its pres context. This may + * be called from within a refresh. + */ + void Disconnect(); + + bool IsFrozen() { return mFreezeCount > 0; } + + /** + * Freeze the refresh driver. It should stop delivering future + * refreshes until thawed. Note that the number of calls to Freeze() must + * match the number of calls to Thaw() in order for the refresh driver to + * be un-frozen. + */ + void Freeze(); + + /** + * Thaw the refresh driver. If the number of calls to Freeze() matches the + * number of calls to this function, the refresh driver should start + * delivering refreshes again. + */ + void Thaw(); + + /** + * Throttle or unthrottle the refresh driver. This is done if the + * corresponding presshell is hidden or shown. + */ + void SetThrottled(bool aThrottled); + + /** + * Return the prescontext we were initialized with + */ + nsPresContext* GetPresContext() const; + + void CreateVsyncRefreshTimer(); + +#ifdef DEBUG + /** + * Check whether the given observer is an observer for the given flush type + */ + bool IsRefreshObserver(nsARefreshObserver* aObserver, + mozilla::FlushType aFlushType); +#endif + + /** + * Default interval the refresh driver uses, in ms. + */ + static int32_t DefaultInterval(); + + bool IsInRefresh() { return mInRefresh; } + + void SetIsResizeSuppressed() { mResizeSuppressed = true; } + bool IsResizeSuppressed() const { return mResizeSuppressed; } + + /** + * The latest value of process-wide jank levels. + * + * For each i, sJankLevels[i] counts the number of times delivery of + * vsync to the main thread has been delayed by at least 2^i + * ms. This data structure has been designed to make it easy to + * determine how much jank has taken place between two instants in + * time. + * + * Return `false` if `aJank` needs to be grown to accomodate the + * data but we didn't have enough memory. + */ + static bool GetJankLevels(mozilla::Vector<uint64_t>& aJank); + + // mozilla::layers::TransactionIdAllocator + TransactionId GetTransactionId(bool aThrottle) override; + TransactionId LastTransactionId() const override; + void NotifyTransactionCompleted(TransactionId aTransactionId) override; + void RevokeTransactionId(TransactionId aTransactionId) override; + void ClearPendingTransactions() override; + void ResetInitialTransactionId(TransactionId aTransactionId) override; + mozilla::TimeStamp GetTransactionStart() override; + mozilla::VsyncId GetVsyncId() override; + mozilla::TimeStamp GetVsyncStart() override; + + bool IsWaitingForPaint(mozilla::TimeStamp aTime); + + // nsARefreshObserver + NS_IMETHOD_(MozExternalRefCountType) AddRef(void) override { + return TransactionIdAllocator::AddRef(); + } + NS_IMETHOD_(MozExternalRefCountType) Release(void) override { + return TransactionIdAllocator::Release(); + } + virtual void WillRefresh(mozilla::TimeStamp aTime) override; + + /** + * Compute the time when the currently active refresh driver timer + * will start its next tick. + * + * Expects a non-null default value that is the upper bound of the + * expected deadline. If the next expected deadline is later than + * the default value, the default value is returned. + * + * If we're animating and we have skipped paints a time in the past + * is returned. + */ + static mozilla::TimeStamp GetIdleDeadlineHint(mozilla::TimeStamp aDefault); + + /** + * It returns the expected timestamp of the next tick or nothing if the next + * tick is missed. + */ + static mozilla::Maybe<mozilla::TimeStamp> GetNextTickHint(); + + static void DispatchIdleRunnableAfterTickUnlessExists(nsIRunnable* aRunnable, + uint32_t aDelay); + static void CancelIdleRunnable(nsIRunnable* aRunnable); + + void NotifyDOMContentLoaded(); + + // Schedule a refresh so that any delayed events will run soon. + void RunDelayedEventsSoon(); + + void InitializeTimer() { + MOZ_ASSERT(!mActiveTimer); + EnsureTimerStarted(); + } + + bool HasPendingTick() const { return mActiveTimer; } + + void EnsureIntersectionObservationsUpdateHappens() { + // This is enough to make sure that UpdateIntersectionObservations runs at + // least once. This is presumably the intent of step 5 in [1]: + // + // Schedule an iteration of the event loop in the root's browsing + // context. + // + // Though the wording of it is not quite clear to me... + // + // [1]: + // https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-observe + EnsureTimerStarted(); + mNeedToUpdateIntersectionObservations = true; + } + + // Register a composition payload that will be forwarded to the layer manager + // if the current or upcoming refresh tick does a paint. + // If no paint happens, the payload is discarded. + // Should only be called on root refresh drivers. + void RegisterCompositionPayload( + const mozilla::layers::CompositionPayload& aPayload); + + enum class TickReasons : uint32_t { + eNone = 0, + eHasObservers = 1 << 0, + eHasImageRequests = 1 << 1, + eNeedsToUpdateIntersectionObservations = 1 << 2, + eHasVisualViewportResizeEvents = 1 << 3, + eHasScrollEvents = 1 << 4, + eHasVisualViewportScrollEvents = 1 << 5, + }; + + private: + typedef nsTArray<RefPtr<VVPResizeEvent>> VisualViewportResizeEventArray; + typedef nsTArray<RefPtr<mozilla::Runnable>> ScrollEventArray; + typedef nsTArray<RefPtr<VVPScrollEvent>> VisualViewportScrollEventArray; + typedef nsTHashtable<nsISupportsHashKey> RequestTable; + struct ImageStartData { + ImageStartData() = default; + + mozilla::Maybe<mozilla::TimeStamp> mStartTime; + RequestTable mEntries; + }; + typedef nsClassHashtable<nsUint32HashKey, ImageStartData> ImageStartTable; + + struct ObserverData { + nsARefreshObserver* mObserver; + const char* mDescription; + mozilla::TimeStamp mRegisterTime; + mozilla::Maybe<uint64_t> mInnerWindowId; +#ifdef MOZ_GECKO_PROFILER + mozilla::UniquePtr<mozilla::ProfileChunkedBuffer> mCause; +#endif + mozilla::FlushType mFlushType; + + bool operator==(nsARefreshObserver* aObserver) const { + return mObserver == aObserver; + } + operator RefPtr<nsARefreshObserver>() { return mObserver; } + }; + typedef nsTObserverArray<ObserverData> ObserverArray; + void RunFullscreenSteps(); + void DispatchAnimationEvents(); + MOZ_CAN_RUN_SCRIPT + void RunFrameRequestCallbacks(mozilla::TimeStamp aNowTime); + void UpdateIntersectionObservations(mozilla::TimeStamp aNowTime); + MOZ_CAN_RUN_SCRIPT_BOUNDARY + void Tick(mozilla::VsyncId aId, mozilla::TimeStamp aNowTime); + + enum EnsureTimerStartedFlags { + eNone = 0, + eForceAdjustTimer = 1 << 0, + eAllowTimeToGoBackwards = 1 << 1, + eNeverAdjustTimer = 1 << 2, + }; + void EnsureTimerStarted(EnsureTimerStartedFlags aFlags = eNone); + void StopTimer(); + + bool HasObservers() const; + void AppendObserverDescriptionsToString(nsACString& aStr) const; + // Note: This should only be called in the dtor of nsRefreshDriver. + uint32_t ObserverCount() const; + bool HasImageRequests() const; + bool ShouldKeepTimerRunningWhileWaitingForFirstContentfulPaint(); + ObserverArray& ArrayFor(mozilla::FlushType aFlushType); + // Trigger a refresh immediately, if haven't been disconnected or frozen. + void DoRefresh(); + + TickReasons GetReasonsToTick() const; + void AppendTickReasonsToString(TickReasons aReasons, nsACString& aStr) const; + + double GetRegularTimerInterval() const; + static double GetThrottledTimerInterval(); + + static mozilla::TimeDuration GetMinRecomputeVisibilityInterval(); + + bool HaveFrameRequestCallbacks() const { + return mFrameRequestCallbackDocs.Length() != 0; + } + + void FinishedWaitingForTransaction(); + + mozilla::RefreshDriverTimer* ChooseTimer(); + mozilla::RefreshDriverTimer* mActiveTimer; + RefPtr<mozilla::RefreshDriverTimer> mOwnTimer; +#ifdef MOZ_GECKO_PROFILER + mozilla::UniquePtr<mozilla::ProfileChunkedBuffer> mRefreshTimerStartedCause; +#endif + + // nsPresContext passed in constructor and unset in Disconnect. + mozilla::WeakPtr<nsPresContext> mPresContext; + + RefPtr<nsRefreshDriver> mRootRefresh; + + // The most recently allocated transaction id. + TransactionId mNextTransactionId; + // This number is mCompletedTransaction + (pending transaction count). + // When we revoke a transaction id, we revert this number (since it's + // no longer outstanding), but not mNextTransactionId (since we don't + // want to reuse the number). + TransactionId mOutstandingTransactionId; + // The most recently completed transaction id. + TransactionId mCompletedTransaction; + + uint32_t mFreezeCount; + + // How long we wait between ticks for throttled (which generally means + // non-visible) documents registered with a non-throttled refresh driver. + const mozilla::TimeDuration mThrottledFrameRequestInterval; + + // How long we wait, at a minimum, before recomputing approximate frame + // visibility information. This is a minimum because, regardless of this + // interval, we only recompute visibility when we've seen a layout or style + // flush since the last time we did it. + const mozilla::TimeDuration mMinRecomputeVisibilityInterval; + +#ifdef MOZ_GECKO_PROFILER + mozilla::UniquePtr<mozilla::ProfileChunkedBuffer> mViewManagerFlushCause; +#endif + + bool mThrottled : 1; + bool mNeedToRecomputeVisibility : 1; + bool mTestControllingRefreshes : 1; + + // These two fields are almost the same, the only difference is that + // mViewManagerFlushIsPending gets cleared right before calling + // ProcessPendingUpdates, and mHasScheduleFlush gets cleared right after + // calling ProcessPendingUpdates. It is important that mHasScheduleFlush + // only gets cleared after, but it's not clear if mViewManagerFlushIsPending + // needs to be cleared before. + bool mViewManagerFlushIsPending : 1; + bool mHasScheduleFlush : 1; + + bool mInRefresh : 1; + + // True if the refresh driver is suspended waiting for transaction + // id's to be returned and shouldn't do any work during Tick(). + bool mWaitingForTransaction : 1; + // True if Tick() was skipped because of mWaitingForTransaction and + // we should schedule a new Tick immediately when resumed instead + // of waiting until the next interval. + bool mSkippedPaints : 1; + + // True if view managers should delay any resize request until the + // next tick by the refresh driver. This flag will be reset at the + // start of every tick. + bool mResizeSuppressed : 1; + + // True if the next tick should notify DOMContentFlushed. + bool mNotifyDOMContentFlushed : 1; + + // True if we need to flush in order to update intersection observations in + // all our documents. + bool mNeedToUpdateIntersectionObservations : 1; + + // Number of seconds that the refresh driver is blocked waiting for a + // compositor transaction to be completed before we append a note to the gfx + // critical log. The number is doubled every time the threshold is hit. + uint64_t mWarningThreshold; + mozilla::TimeStamp mMostRecentRefresh; + mozilla::TimeStamp mTickStart; + mozilla::VsyncId mTickVsyncId; + mozilla::TimeStamp mTickVsyncTime; + mozilla::TimeStamp mNextThrottledFrameRequestTick; + mozilla::TimeStamp mNextRecomputeVisibilityTick; + mozilla::TimeStamp mBeforeFirstContentfulPaintTimerRunningLimit; + + // separate arrays for each flush type we support + ObserverArray mObservers[4]; + // These observers should NOT be included in HasObservers() since that method + // is used to determine whether or not to stop the timer, or restore it when + // thawing the refresh driver. On the other hand these observers are intended + // to be called when the timer is re-started and should not influence its + // starting or stopping. + nsTObserverArray<nsATimerAdjustmentObserver*> mTimerAdjustmentObservers; + nsTArray<mozilla::layers::CompositionPayload> mCompositionPayloads; + RequestTable mRequests; + ImageStartTable mStartTable; + AutoTArray<nsCOMPtr<nsIRunnable>, 16> mEarlyRunners; + VisualViewportResizeEventArray mVisualViewportResizeEvents; + ScrollEventArray mScrollEvents; + VisualViewportScrollEventArray mVisualViewportScrollEvents; + + // Scroll events on documents that might have events suppressed. + ScrollEventArray mDelayedScrollEvents; + + AutoTArray<mozilla::PresShell*, 16> mResizeEventFlushObservers; + AutoTArray<mozilla::PresShell*, 16> mDelayedResizeEventFlushObservers; + AutoTArray<mozilla::PresShell*, 16> mStyleFlushObservers; + AutoTArray<mozilla::PresShell*, 16> mLayoutFlushObservers; + // nsTArray on purpose, because we want to be able to swap. + nsTArray<Document*> mFrameRequestCallbackDocs; + nsTArray<Document*> mThrottledFrameRequestCallbackDocs; + nsTObserverArray<nsAPostRefreshObserver*> mPostRefreshObservers; + nsTArray<mozilla::UniquePtr<mozilla::PendingFullscreenEvent>> + mPendingFullscreenEvents; + AutoTArray<mozilla::AnimationEventDispatcher*, 16> + mAnimationEventFlushObservers; + + void BeginRefreshingImages(RequestTable& aEntries, + mozilla::TimeStamp aDesired); + + friend class mozilla::RefreshDriverTimer; + + static void Shutdown(); + + // `true` if we are currently in jank-critical mode. + // + // In jank-critical mode, any iteration of the event loop that takes + // more than 16ms to compute will cause an ongoing animation to miss + // frames. + // + // For simplicity, the current implementation assumes that we are + // in jank-critical mode if and only if the vsync driver has at least + // one observer. + static bool IsJankCritical(); +}; + +#endif /* !defined(nsRefreshDriver_h_) */ |