Bug 1186662 - Part 1: Add SuppressDisplayport painting and use it during tab switch. r=kats,mconley

--HG--
extra : commitid : 9fUfVIK8ikm
extra : rebase_source : e45570f97a25f965d2caf24f152da02efcf6495f

browser/base/content/tabbrowser.xml

@@ -3077,6 +3077,11 @@
             // Map from tabs to STATE_* (below).
             tabState: new Map(),
 
+            // Keep an exact list of content processes (tabParent) in which
+            // we're actively suppressing the display port. This gives a robust
+            // way to make sure we don't forget to un-suppress.
+            activeSuppressDisplayport: new Set(),
+
             // Set of tabs that might be visible right now. We maintain
             // this set because we can't be sure when a tab is actually
             // drawn. A tab is added to this set when we ask to make it
@@ -3140,6 +3145,11 @@
               window.removeEventListener("TabRemotenessChange", this);
 
               this.tabbrowser._switcher = null;
+
+              this.activeSuppressDisplayport.forEach(function(tabParent) {
+                tabParent.suppressDisplayport(false);
+              });
+              this.activeSuppressDisplayport.clear();
             },
 
             finish: function() {
@@ -3438,6 +3448,13 @@
 
               this.requestedTab = tab;
 
+              let browser = this.requestedTab.linkedBrowser;
+              let fl = browser.QueryInterface(Ci.nsIFrameLoaderOwner).frameLoader;
+              if (fl && fl.tabParent && !this.activeSuppressDisplayport.has(fl.tabParent)) {
+                fl.tabParent.suppressDisplayport(true);
+                this.activeSuppressDisplayport.add(fl.tabParent);
+              }
+
               this.preActions();
 
               clearTimeout(this.unloadTimer);

dom/interfaces/base/nsITabParent.idl

@@ -5,7 +5,7 @@
 
 #include "domstubs.idl"
 
-[scriptable, uuid(CE6F563B-BD77-4EF2-9D7C-A94C587353E4)]
+[scriptable, uuid(531b902b-b551-4faa-9814-1a73e8299ac4)]
 interface nsITabParent : nsISupports
 {
   void injectTouchEvent(in AString aType,
@@ -25,6 +25,14 @@ interface nsITabParent : nsISupports
 
   void setIsDocShellActive(in bool aIsActive);
 
+  /**
+   * During interactions where painting performance
+   * is more important than scrolling, we may temporarily
+   * suppress the displayport. Each enable called must be matched
+   * with a disable call.
+   */
+  void suppressDisplayport(in bool aEnabled);
+
   readonly attribute uint64_t tabId;
 
   /**

dom/ipc/PBrowser.ipdl

@@ -709,6 +709,17 @@ child:
      */
     SetIsDocShellActive(bool aIsActive);
 
+    /**
+     * Notify the child that it shouldn't paint the offscreen displayport.
+     * This is useful to speed up interactive operations over async
+     * scrolling performance like resize, tabswitch, pageload.
+     *
+     * Each enable call must be matched with a disable call. The child
+     * will remain in the suppress mode as long as there's
+     * a single unmatched call.
+     */
+    async SuppressDisplayport(bool aEnabled);
+
     /**
      * Navigate by key (Tab/Shift+Tab/F6/Shift+f6).
      */

dom/ipc/TabChild.cpp

@@ -554,6 +554,7 @@ TabChild::TabChild(nsIContentChild* aManager,
   , mRemoteFrame(nullptr)
   , mManager(aManager)
   , mChromeFlags(aChromeFlags)
+  , mActiveSuppressDisplayport(0)
   , mLayersId(0)
   , mActivePointerId(-1)
   , mAppPackageFileDescriptorRecved(false)
@@ -1693,6 +1694,20 @@ TabChild::RecvUpdateFrame(const FrameMetrics& aFrameMetrics)
   return TabChildBase::UpdateFrameHandler(aFrameMetrics);
 }
 
+bool
+TabChild::RecvSuppressDisplayport(const bool& aEnabled)
+{
+  if (aEnabled) {
+    mActiveSuppressDisplayport++;
+  } else {
+    mActiveSuppressDisplayport--;
+  }
+
+  MOZ_ASSERT(mActiveSuppressDisplayport >= 0);
+  APZCCallbackHelper::SuppressDisplayport(aEnabled);
+  return true;
+}
+
 bool
 TabChild::RecvRequestFlingSnap(const FrameMetrics::ViewID& aScrollId,
                                const mozilla::CSSPoint& aDestination)
@@ -2413,6 +2428,11 @@ TabChild::RecvDestroy()
   MOZ_ASSERT(mDestroyed == false);
   mDestroyed = true;
 
+  while (mActiveSuppressDisplayport > 0) {
+    APZCCallbackHelper::SuppressDisplayport(false);
+    mActiveSuppressDisplayport--;
+  }
+
   if (mTabChildGlobal) {
     // Message handlers are called from the event loop, so it better be safe to
     // run script.

dom/ipc/TabChild.h

@@ -512,6 +512,8 @@ protected:
 
     virtual bool RecvRequestNotifyAfterRemotePaint() override;
 
+    virtual bool RecvSuppressDisplayport(const bool& aEnabled) override;
+
     virtual bool RecvParentActivated(const bool& aActivated) override;
 
     virtual bool RecvStopIMEStateManagement() override;
@@ -608,6 +610,7 @@ private:
     RenderFrameChild* mRemoteFrame;
     nsRefPtr<nsIContentChild> mManager;
     uint32_t mChromeFlags;
+    int32_t mActiveSuppressDisplayport;
     uint64_t mLayersId;
     CSSRect mUnscaledOuterRect;
     // When we're tracking a possible tap gesture, this is the "down"

dom/ipc/TabParent.cpp

@@ -287,6 +287,7 @@ TabParent::TabParent(nsIContentParent* aManager,
   , mCursor(nsCursor(-1))
   , mTabSetsCursor(false)
   , mHasContentOpener(false)
+  , mActiveSupressDisplayportCount(0)
 {
   MOZ_ASSERT(aManager);
 }
@@ -2955,6 +2956,25 @@ TabParent::SetIsDocShellActive(bool isActive)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+TabParent::SuppressDisplayport(bool aEnabled)
+{
+  if (IsDestroyed()) {
+    return NS_OK;
+  }
+
+  if (aEnabled) {
+    mActiveSupressDisplayportCount++;
+  } else {
+    mActiveSupressDisplayportCount--;
+  }
+
+  MOZ_ASSERT(mActiveSupressDisplayportCount >= 0);
+
+  unused << SendSuppressDisplayport(aEnabled);
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 TabParent::GetTabId(uint64_t* aId)
 {

dom/ipc/TabParent.h

@@ -609,6 +609,8 @@ private:
     nsRefPtr<nsIPresShell> mPresShellWithRefreshListener;
 
     bool mHasContentOpener;
+
+    DebugOnly<int32_t> mActiveSupressDisplayportCount;
 private:
     // This is used when APZ needs to find the TabParent associated with a layer
     // to dispatch events.

gfx/layers/apz/util/APZCCallbackHelper.cpp

@@ -810,6 +810,27 @@ APZCCallbackHelper::NotifyFlushComplete()
   observerService->NotifyObservers(nullptr, "apz-repaints-flushed", nullptr);
 }
 
+static int32_t sActiveSuppressDisplayport = 0;
+
+void
+APZCCallbackHelper::SuppressDisplayport(const bool& aEnabled)
+{
+  if (aEnabled) {
+    sActiveSuppressDisplayport++;
+  } else {
+    sActiveSuppressDisplayport--;
+  }
+
+  MOZ_ASSERT(sActiveSuppressDisplayport >= 0);
+}
+
+bool
+APZCCallbackHelper::IsDisplayportSuppressed()
+{
+  return sActiveSuppressDisplayport > 0;
+}
+
+
 } // namespace layers
 } // namespace mozilla
 

gfx/layers/apz/util/APZCCallbackHelper.h

@@ -169,6 +169,10 @@ public:
 
     /* Notify content that the repaint flush is complete. */
     static void NotifyFlushComplete();
+
+    /* Temporarily ignore the Displayport for better paint performance. */
+    static void SuppressDisplayport(const bool& aEnabled);
+    static bool IsDisplayportSuppressed();
 };
 
 } // namespace layers

layout/base/nsLayoutUtils.cpp

@@ -62,6 +62,7 @@
 #include "mozilla/dom/HTMLImageElement.h"
 #include "mozilla/dom/DOMRect.h"
 #include "mozilla/dom/KeyframeEffect.h"
+#include "mozilla/layers/APZCCallbackHelper.h"
 #include "imgIRequest.h"
 #include "nsIImageLoadingContent.h"
 #include "nsCOMPtr.h"
@@ -1038,7 +1039,10 @@ GetDisplayPortImpl(nsIContent* aContent, nsRect *aResult, float aMultiplier)
                "Only one of rectData or marginsData should be set!");
 
   nsRect result;
-  if (rectData) {
+  if (APZCCallbackHelper::IsDisplayportSuppressed()) {
+    DisplayPortMarginsPropertyData noMargins(ScreenMargin(), 1);
+    result = GetDisplayPortFromMarginsData(aContent, &noMargins, aMultiplier);
+  } else if (rectData) {
     result = GetDisplayPortFromRectData(aContent, rectData, aMultiplier);
   } else {
     result = GetDisplayPortFromMarginsData(aContent, marginsData, aMultiplier);