Oilpan: Schedule a precise GC when a page navigates

Source/platform/heap/ThreadState.h

Index: Source/platform/heap/ThreadState.h
diff --git a/Source/platform/heap/ThreadState.h b/Source/platform/heap/ThreadState.h
index 0c015aeee37db03a46d4f7c03e250cddb3e39ba8..718c07e4e78fdf2995daefa4fa3207a16a22b8c9 100644
--- a/Source/platform/heap/ThreadState.h
+++ b/Source/platform/heap/ThreadState.h
@@ -185,6 +185,7 @@ public:
         IdleGCScheduled,
         PreciseGCScheduled,
         FullGCScheduled,
+        PageNavigationGCScheduled,

[haraken, 2015/08/11 07:43:08]

You need to add PageNavigationGCScheduled to ThreadState::setGCState. I think
the transition should be very similar to PreciseGCScheduled.

[keishi, 2015/08/11 08:12:58]

Please check the change to ThreadState::setGCState to see if I got this right.
PageNavigationGCScheduled can be set while NoGCScheduled or any of
theGCScheduled states and I didn't do completeSweep because I already do it in
ThreadState::schedulePageNavigationGCIfNeeded.

         GCRunning,
         EagerSweepScheduled,
         LazySweepScheduled,
@@ -329,6 +330,11 @@ public:
     void scheduleIdleGC();
     void scheduleIdleLazySweep();
     void schedulePreciseGC();
+    // estimatedRemovalRatio is the estimated ratio of objects that will be no
+    // longer necessary due to the navigation.
+    bool shouldSchedulePageNavigationGC(float estimatedRemovalRatio);

[haraken, 2015/08/11 07:43:08]

Move this declaration to the other shouldScheduleXXX methods.

[keishi, 2015/08/11 08:12:58]

Done.

+    void schedulePageNavigationGCIfNeeded(float estimatedRemovalRatio);
+    void schedulePageNavigationGC();
     void scheduleGCIfNeeded();
     void setGCState(GCState);
     GCState gcState() const;