Bug 1421704 - Optimize NotifyVisited IPC to take batch r=mak

During history import, sending NotifyVisited messages from the
chrome process to the content processes in order to change link
colors can take a significant portion of the parent process's
main thread time. Batching it seems to have very significant
results on jank time during history imports.

MozReview-Commit-ID: BHAXpIMa7ly

--HG--
extra : rebase_source : f43c653e6945d7775cc9dd7bca4c1e84099c2673

dom/ipc/ContentChild.cpp

@@ -2453,15 +2453,17 @@ ContentChild::RecvNotifyAlertsObserver(const nsCString& aType, const nsString& a
 // NOTE: This method is being run in the SystemGroup, and thus cannot directly
 // touch pages. See GetSpecificMessageEventTarget.
 mozilla::ipc::IPCResult
-ContentChild::RecvNotifyVisited(const URIParams& aURI)
+ContentChild::RecvNotifyVisited(nsTArray<URIParams>&& aURIs)
 {
-  nsCOMPtr<nsIURI> newURI = DeserializeURI(aURI);
-  if (!newURI) {
-    return IPC_FAIL_NO_REASON(this);
-  }
-  nsCOMPtr<IHistory> history = services::GetHistoryService();
-  if (history) {
-    history->NotifyVisited(newURI);
+  for (const URIParams& uri : aURIs) {
+    nsCOMPtr<nsIURI> newURI = DeserializeURI(uri);
+    if (!newURI) {
+      return IPC_FAIL_NO_REASON(this);
+    }
+    nsCOMPtr<IHistory> history = services::GetHistoryService();
+    if (history) {
+      history->NotifyVisited(newURI);
+    }
   }
   return IPC_OK();
 }

dom/ipc/ContentChild.h

@@ -362,7 +362,7 @@ public:
   virtual mozilla::ipc::IPCResult RecvBidiKeyboardNotify(const bool& isLangRTL,
                                                          const bool& haveBidiKeyboards) override;
 
-  virtual mozilla::ipc::IPCResult RecvNotifyVisited(const URIParams& aURI) override;
+  virtual mozilla::ipc::IPCResult RecvNotifyVisited(nsTArray<URIParams>&& aURIs) override;
 
   // auto remove when alertfinished is received.
   nsresult AddRemoteAlertObserver(const nsString& aData, nsIObserver* aObserver);

dom/ipc/PContent.ipdl

@@ -426,7 +426,7 @@ child:
     async SetConnectivity(bool connectivity);
     async SetCaptivePortalState(int32_t aState);
 
-    async NotifyVisited(URIParams uri);
+    async NotifyVisited(URIParams[] uri);
 
     async PreferenceUpdate(Pref pref);
     async VarUpdate(GfxVarUpdate var);

toolkit/components/places/History.cpp

@@ -575,6 +575,11 @@ public:
       History* history = History::GetService();
       NS_ENSURE_STATE(history);
       history->NotifyVisited(mURI);
+      AutoTArray<URIParams, 1> uris;
+      URIParams uri;
+      SerializeURI(mURI, uri);
+      uris.AppendElement(Move(uri));
+      history->NotifyVisitedParent(uris);
     }
 
     nsCOMPtr<nsIObserverService> observerService =
@@ -643,6 +648,7 @@ public:
   nsresult NotifyVisit(nsNavHistory* aNavHistory,
                        nsCOMPtr<nsIObserverService>& aObsService,
                        PRTime aNow,
+                       nsTArray<URIParams>& aNotifyVisitedURIs,
                        VisitData aPlace) {
     nsCOMPtr<nsIURI> uri;
     MOZ_ALWAYS_SUCCEEDS(NS_NewURI(getter_AddRefs(uri), aPlace.spec));
@@ -675,6 +681,10 @@ public:
       aNavHistory->NotifyTitleChange(uri, aPlace.title, aPlace.guid);
     }
 
+    URIParams serialized;
+    SerializeURI(uri, serialized);
+    aNotifyVisitedURIs.AppendElement(Move(serialized));
+
     return NS_OK;
   }
 
@@ -699,13 +709,17 @@ public:
 
     PRTime now = PR_Now();
     if (mPlaces.Length() > 0) {
+      InfallibleTArray<URIParams> uris(mPlaces.Length());
       for (uint32_t i = 0; i < mPlaces.Length(); ++i) {
-        nsresult rv = NotifyVisit(navHistory, obsService, now, mPlaces[i]);
+        nsresult rv = NotifyVisit(navHistory, obsService, now, uris, mPlaces[i]);
         NS_ENSURE_SUCCESS(rv, rv);
       }
+      mHistory->NotifyVisitedParent(uris);
     } else {
-      nsresult rv = NotifyVisit(navHistory, obsService, now, mPlace);
+      AutoTArray<URIParams, 1> uris;
+      nsresult rv = NotifyVisit(navHistory, obsService, now, uris, mPlace);
       NS_ENSURE_SUCCESS(rv, rv);
+      mHistory->NotifyVisitedParent(uris);
     }
 
     return NS_OK;
@@ -1998,6 +2012,20 @@ GetLinkDocument(Link* aLink)
   return element ? element->OwnerDoc() : nullptr;
 }
 
+void
+History::NotifyVisitedParent(const nsTArray<URIParams>& aURIs)
+{
+  MOZ_ASSERT(XRE_IsParentProcess());
+  nsTArray<ContentParent*> cplist;
+  ContentParent::GetAll(cplist);
+
+  if (!cplist.IsEmpty()) {
+    for (uint32_t i = 0; i < cplist.Length(); ++i) {
+      Unused << cplist[i]->SendNotifyVisited(aURIs);
+    }
+  }
+}
+
 NS_IMETHODIMP
 History::NotifyVisited(nsIURI* aURI)
 {
@@ -2008,19 +2036,6 @@ History::NotifyVisited(nsIURI* aURI)
 
   nsAutoScriptBlocker scriptBlocker;
 
-  if (XRE_IsParentProcess()) {
-    nsTArray<ContentParent*> cplist;
-    ContentParent::GetAll(cplist);
-
-    if (!cplist.IsEmpty()) {
-      URIParams uri;
-      SerializeURI(aURI, uri);
-      for (uint32_t i = 0; i < cplist.Length(); ++i) {
-        Unused << cplist[i]->SendNotifyVisited(uri);
-      }
-    }
-  }
-
   // If we have no observers for this URI, we have nothing to notify about.
   KeyClass* key = mObservers.GetEntry(aURI);
   if (!key) {

toolkit/components/places/History.h

@@ -15,6 +15,7 @@
 #include "Database.h"
 
 #include "mozilla/dom/Link.h"
+#include "mozilla/ipc/URIParams.h"
 #include "nsTHashtable.h"
 #include "nsString.h"
 #include "nsURIHashKey.h"
@@ -143,6 +144,7 @@ public:
    */
   void AppendToRecentlyVisitedURIs(nsIURI* aURI);
 
+  void NotifyVisitedParent(const nsTArray<mozilla::ipc::URIParams>& aURIs);
 private:
   virtual ~History();