Bug 716014 Investigate if we could use CompartmentGC more often, r=billm+terrence (add06019) · Commits · Tommy Webb / Tor Browser

dom/base/nsDOMWindowUtils.cpp

+1 −1

Original line number	Diff line number	Diff line
		@@ -1012,7 +1012,7 @@ nsDOMWindowUtils::GarbageCollect(nsICycleCollectorListener *aListener,
		}
		#endif

		nsJSContext::GarbageCollectNow(js::gcreason::DOM_UTILS);
		nsJSContext::GarbageCollectNow(js::gcreason::DOM_UTILS, nsGCNormal, true);
		nsJSContext::CycleCollectNow(aListener, aExtraForgetSkippableCalls);

		return NS_OK;

dom/base/nsJSEnvironment.cpp

+99 −21

Original line number	Diff line number	Diff line
		@@ -134,6 +134,10 @@ static PRLogModuleInfo* gJSDiagnostics;
		// doing the first GC.
		#define NS_FIRST_GC_DELAY 10000 // ms

		#define NS_FULL_GC_DELAY 60000 // ms

		#define NS_MAX_COMPARTMENT_GC_COUNT 20

		// Maximum amount of time that should elapse between incremental GC slices
		#define NS_INTERSLICE_GC_DELAY 100 // ms

		@@ -159,6 +163,7 @@ static PRLogModuleInfo* gJSDiagnostics;
		static nsITimer *sGCTimer;
		static nsITimer *sShrinkGCBuffersTimer;
		static nsITimer *sCCTimer;
		static nsITimer *sFullGCTimer;

		static PRTime sLastCCEndTime;

		@@ -178,6 +183,7 @@ static bool sLoadingInProgress;

		static PRUint32 sCCollectedWaitingForGC;
		static bool sPostGCEventsToConsole;
		static bool sDisableExplicitCompartmentGC;
		static PRUint32 sCCTimerFireCount = 0;
		static PRUint32 sMinForgetSkippableTime = PR_UINT32_MAX;
		static PRUint32 sMaxForgetSkippableTime = 0;
		@@ -185,9 +191,10 @@ static PRUint32 sTotalForgetSkippableTime = 0;
		static PRUint32 sRemovedPurples = 0;
		static PRUint32 sForgetSkippableBeforeCC = 0;
		static PRUint32 sPreviousSuspectedCount = 0;

		static PRUint32 sCompartmentGCCount = NS_MAX_COMPARTMENT_GC_COUNT;
		static PRUint32 sCleanupsSinceLastGC = PR_UINT32_MAX;
		static bool sNeedsFullCC = false;
		static nsJSContext *sContextList = nsnull;

		nsScriptNameSpaceManager *gNameSpaceManager;

		@@ -229,7 +236,8 @@ nsMemoryPressureObserver::Observe(nsISupports* aSubject, const char* aTopic,
		const PRUnichar* aData)
		{
		if (sGCOnMemoryPressure) {
		nsJSContext::GarbageCollectNow(js::gcreason::MEM_PRESSURE, nsGCShrinking);
		nsJSContext::GarbageCollectNow(js::gcreason::MEM_PRESSURE, nsGCShrinking,
		true);
		nsJSContext::CycleCollectNow();
		}
		return NS_OK;
		@@ -929,6 +937,8 @@ static const char js_pccounts_content_str[] = JS_OPTIONS_DOT_STR "pccounts.con
		static const char js_pccounts_chrome_str[] = JS_OPTIONS_DOT_STR "pccounts.chrome";
		static const char js_jit_hardening_str[] = JS_OPTIONS_DOT_STR "jit_hardening";
		static const char js_memlog_option_str[] = JS_OPTIONS_DOT_STR "mem.log";
		static const char js_disable_explicit_compartment_gc[] =
		JS_OPTIONS_DOT_STR "disable_explicit_compartment_gc";

		int
		nsJSContext::JSOptionChangedCallback(const char pref, void data)
		@@ -938,6 +948,8 @@ nsJSContext::JSOptionChangedCallback(const char pref, void data)
		PRUint32 newDefaultJSOptions = oldDefaultJSOptions;

		sPostGCEventsToConsole = Preferences::GetBool(js_memlog_option_str);
		sDisableExplicitCompartmentGC =
		Preferences::GetBool(js_disable_explicit_compartment_gc);

		bool strict = Preferences::GetBool(js_strict_option_str);
		if (strict)
		@@ -1038,9 +1050,16 @@ nsJSContext::JSOptionChangedCallback(const char pref, void data)
		}

		nsJSContext::nsJSContext(JSRuntime *aRuntime)
		: mGCOnDestruction(true),
		: mActive(false),
		mGCOnDestruction(true),
		mExecuteDepth(0)
		{
		mNext = sContextList;
		mPrev = &sContextList;
		if (sContextList) {
		sContextList->mPrev = &mNext;
		}
		sContextList = this;

		++sContextCount;

		@@ -1079,6 +1098,11 @@ nsJSContext::~nsJSContext()
		nsCycleCollector_DEBUG_wasFreed(static_cast<nsIScriptContext*>(this));
		#endif

		*mPrev = mNext;
		if (mNext) {
		mNext->mPrev = mPrev;
		}

		// We may still have pending termination functions if the context is destroyed
		// before they could be executed. In this case, free the references to their
		// parameters, but don't execute the functions (see bug 622326).
		@@ -2849,6 +2873,7 @@ nsJSContext::ScriptEvaluated(bool aTerminated)
		if (aTerminated) {
		mOperationCallbackTime = 0;
		mModalStateTime = 0;
		mActive = true;
		}
		}

		@@ -2916,9 +2941,20 @@ nsJSContext::ScriptExecuted()
		return NS_OK;
		}

		void
		FullGCTimerFired(nsITimer* aTimer, void* aClosure)
		{
		NS_RELEASE(sFullGCTimer);

		uintptr_t reason = reinterpret_cast<uintptr_t>(aClosure);
		nsJSContext::GarbageCollectNow(static_cast<js::gcreason::Reason>(reason),
		nsGCNormal, true);
		}

		//static
		void
		nsJSContext::GarbageCollectNow(js::gcreason::Reason reason, PRUint32 gckind)
		nsJSContext::GarbageCollectNow(js::gcreason::Reason aReason, PRUint32 aGckind,
		bool aGlobal)
		{
		NS_TIME_FUNCTION_MIN(1.0);
		SAMPLE_LABEL("GC", "GarbageCollectNow");
		@@ -2935,9 +2971,35 @@ nsJSContext::GarbageCollectNow(js::gcreason::Reason reason, PRUint32 gckind)
		sPendingLoadCount = 0;
		sLoadingInProgress = false;

		if (nsContentUtils::XPConnect()) {
		nsContentUtils::XPConnect()->GarbageCollect(reason, gckind);
		if (!nsContentUtils::XPConnect()) {
		return;
		}

		// Use compartment GC when we're not asked to do a shrinking GC nor
		// global GC and compartment GC has been called less than
		// NS_MAX_COMPARTMENT_GC_COUNT times after the previous global GC.
		if (!sDisableExplicitCompartmentGC &&
		aGckind != nsGCShrinking && !aGlobal &&
		sCompartmentGCCount < NS_MAX_COMPARTMENT_GC_COUNT) {
		js::PrepareForFullGC(nsJSRuntime::sRuntime);
		for (nsJSContext* cx = sContextList; cx; cx = cx->mNext) {
		if (!cx->mActive && cx->mContext) {
		if (JSObject* global = cx->GetNativeGlobal()) {
		js::SkipCompartmentForGC(js::GetObjectCompartment(global));
		}
		}
		cx->mActive = false;
		}
		if (js::IsGCScheduled(nsJSRuntime::sRuntime)) {
		js::IncrementalGC(nsJSRuntime::sRuntime, aReason);
		}
		return;
		}

		for (nsJSContext* cx = sContextList; cx; cx = cx->mNext) {
		cx->mActive = false;
		}
		nsContentUtils::XPConnect()->GarbageCollect(aReason, aGckind);
		}

		//static
		@@ -2963,7 +3025,7 @@ nsJSContext::CycleCollectNow(nsICycleCollectorListener *aListener,

		if (sCCLockedOut) {
		// We're in the middle of an incremental GC; finish it first
		nsJSContext::GarbageCollectNow(js::gcreason::CC_FORCED, nsGCNormal);
		nsJSContext::GarbageCollectNow(js::gcreason::CC_FORCED, nsGCNormal, true);
		}

		SAMPLE_LABEL("GC", "CycleCollectNow");
		@@ -3100,7 +3162,8 @@ GCTimerFired(nsITimer aTimer, void aClosure)
		NS_RELEASE(sGCTimer);

		uintptr_t reason = reinterpret_cast<uintptr_t>(aClosure);
		nsJSContext::GarbageCollectNow(static_cast<js::gcreason::Reason>(reason), nsGCIncremental);
		nsJSContext::GarbageCollectNow(static_cast<js::gcreason::Reason>(reason),
		nsGCNormal, false);
		}

		void
		@@ -3156,7 +3219,7 @@ CCTimerFired(nsITimer aTimer, void aClosure)
		}

		// Finish the current incremental GC
		nsJSContext::GarbageCollectNow(js::gcreason::CC_FORCED, nsGCNormal);
		nsJSContext::GarbageCollectNow(js::gcreason::CC_FORCED, nsGCNormal, true);
		}

		++sCCTimerFireCount;
		@@ -3309,6 +3372,15 @@ nsJSContext::KillGCTimer()
		}
		}

		void
		nsJSContext::KillFullGCTimer()
		{
		if (sFullGCTimer) {
		sFullGCTimer->Cancel();
		NS_RELEASE(sFullGCTimer);
		}
		}

		//static
		void
		nsJSContext::KillShrinkGCBuffersTimer()
		@@ -3336,6 +3408,7 @@ nsJSContext::KillCCTimer()
		void
		nsJSContext::GC(js::gcreason::Reason aReason)
		{
		mActive = true;
		PokeGC(aReason);
		}

		@@ -3417,20 +3490,23 @@ DOMGCSliceCallback(JSRuntime *aRt, js::GCProgress aProgress, const js::GCDescrip

		sCCollectedWaitingForGC = 0;
		sCleanupsSinceLastGC = 0;
		sNeedsFullCC = true;
		nsJSContext::MaybePokeCC();

		if (aDesc.isCompartment) {
		// If this is a compartment GC, restart it. We still want
		// a full GC to happen. Compartment GCs usually happen as a
		// result of last-ditch or MaybeGC. In both cases it is
		// probably a time of heavy activity and we want to delay
		// the full GC, but we do want it to happen eventually.
		nsJSContext::PokeGC(js::gcreason::POST_COMPARTMENT);
		++sCompartmentGCCount;
		if (!sFullGCTimer) {
		CallCreateInstance("@mozilla.org/timer;1", &sFullGCTimer);
		js::gcreason::Reason reason = js::gcreason::FULL_GC_TIMER;
		sFullGCTimer->InitWithFuncCallback(FullGCTimerFired,
		reinterpret_cast<void *>(reason),
		NS_FULL_GC_DELAY,
		nsITimer::TYPE_ONE_SHOT);
		}
		} else {
		sCompartmentGCCount = 0;
		nsJSContext::KillFullGCTimer();

		sNeedsFullCC = true;
		nsJSContext::MaybePokeCC();

		if (!aDesc.isCompartment) {
		// Avoid shrinking during heavy activity, which is suggested by
		// compartment GC.
		nsJSContext::PokeShrinkGCBuffers();
		@@ -3530,7 +3606,7 @@ void
		nsJSRuntime::Startup()
		{
		// initialize all our statics, so that we can restart XPCOM
		sGCTimer = sCCTimer = nsnull;
		sGCTimer = sFullGCTimer = sCCTimer = nsnull;
		sCCLockedOut = false;
		sCCLockedOutTime = 0;
		sLastCCEndTime = 0;
		@@ -3538,6 +3614,7 @@ nsJSRuntime::Startup()
		sLoadingInProgress = false;
		sCCollectedWaitingForGC = 0;
		sPostGCEventsToConsole = false;
		sDisableExplicitCompartmentGC = false;
		sNeedsFullCC = false;
		gNameSpaceManager = nsnull;
		sRuntimeService = nsnull;
		@@ -3829,6 +3906,7 @@ nsJSRuntime::Shutdown()
		nsJSContext::KillGCTimer();
		nsJSContext::KillShrinkGCBuffersTimer();
		nsJSContext::KillCCTimer();
		nsJSContext::KillFullGCTimer();

		NS_IF_RELEASE(gNameSpaceManager);

dom/base/nsJSEnvironment.h

+8 −2

Original line number	Diff line number	Diff line
		@@ -184,7 +184,9 @@ public:
		static void LoadStart();
		static void LoadEnd();

		static void GarbageCollectNow(js::gcreason::Reason reason, PRUint32 gckind = nsGCNormal);
		static void GarbageCollectNow(js::gcreason::Reason reason,
		PRUint32 aGckind,
		bool aGlobal);
		static void ShrinkGCBuffersNow();
		// If aExtraForgetSkippableCalls is -1, forgetSkippable won't be
		// called even if the previous collection was GC.
		@@ -199,6 +201,7 @@ public:

		static void MaybePokeCC();
		static void KillCCTimer();
		static void KillFullGCTimer();

		virtual void GC(js::gcreason::Reason aReason);

		@@ -238,7 +241,7 @@ private:
		nsrefcnt GetCCRefcnt();

		JSContext *mContext;
		PRUint32 mNumEvaluations;
		bool mActive;

		protected:
		struct TerminationFuncHolder;
		@@ -307,6 +310,9 @@ private:
		PRTime mModalStateTime;
		PRUint32 mModalStateDepth;

		nsJSContext *mNext;
		nsJSContext **mPrev;

		// mGlobalObjectRef ensures that the outer window stays alive as long as the
		// context does. It is eventually collected by the cycle collector.
		nsCOMPtr<nsIScriptGlobalObject> mGlobalObjectRef;

dom/ipc/ContentChild.cpp

+2 −2

Original line number	Diff line number	Diff line
		@@ -791,14 +791,14 @@ ContentChild::GetIndexedDBPath()
		bool
		ContentChild::RecvGarbageCollect()
		{
		nsJSContext::GarbageCollectNow(js::gcreason::DOM_IPC);
		nsJSContext::GarbageCollectNow(js::gcreason::DOM_IPC, nsGCNormal, true);
		return true;
		}

		bool
		ContentChild::RecvCycleCollect()
		{
		nsJSContext::GarbageCollectNow(js::gcreason::DOM_IPC);
		nsJSContext::GarbageCollectNow(js::gcreason::DOM_IPC, nsGCNormal, true);
		nsJSContext::CycleCollectNow();
		return true;
		}

js/src/jscompartment.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -172,6 +172,12 @@ struct JSCompartment
		gcState = GCScheduled;
		}

		void unscheduleGC() {
		JS_ASSERT(!rt->gcRunning);
		JS_ASSERT(gcState != GCRunning);
		gcState = NoGCScheduled;
		}

		bool isGCScheduled() const {
		return gcState == GCScheduled;
		}