forked from mirrors/gecko-dev
2359bca10c
The patch forces a budget check when we start marking or sweeping unless we have just started a GC slice in the current state. This turned out more complicated than expected because the change caused a test that called gcslice(1) in a loop to not make any progress. This was because the original stepAndForceCheck() method ate the single unit of work budget. The fix was to remove the step part of this method. I don't think any of the callers need it to step the budget as well. Differential Revision: https://phabricator.services.mozilla.com/D193925
2028 lines
68 KiB
C++
2028 lines
68 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=8 sts=2 et sw=2 tw=80: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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// We're dividing JS objects into 3 categories:
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//
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// 1. "real" roots, held by the JS engine itself or rooted through the root
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// and lock JS APIs. Roots from this category are considered black in the
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// cycle collector, any cycle they participate in is uncollectable.
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//
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// 2. certain roots held by C++ objects that are guaranteed to be alive.
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// Roots from this category are considered black in the cycle collector,
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// and any cycle they participate in is uncollectable. These roots are
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// traced from TraceNativeBlackRoots.
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//
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// 3. all other roots held by C++ objects that participate in cycle collection,
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// held by us (see TraceNativeGrayRoots). Roots from this category are
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// considered grey in the cycle collector; whether or not they are collected
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// depends on the objects that hold them.
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//
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// Note that if a root is in multiple categories the fact that it is in
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// category 1 or 2 that takes precedence, so it will be considered black.
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//
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// During garbage collection we switch to an additional mark color (gray) when
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// tracing inside TraceNativeGrayRoots. This allows us to walk those roots later
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// on and add all objects reachable only from them to the cycle collector.
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//
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// Phases:
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//
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// 1. marking of the roots in category 1 by having the JS GC do its marking
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// 2. marking of the roots in category 2 by having the JS GC call us back
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// (via JS_SetExtraGCRootsTracer) and running TraceNativeBlackRoots
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// 3. marking of the roots in category 3 by
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// TraceNativeGrayRootsInCollectingZones using an additional color (gray).
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// 4. end of GC, GC can sweep its heap
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//
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// At some later point, when the cycle collector runs:
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//
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// 5. walk gray objects and add them to the cycle collector, cycle collect
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//
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// JS objects that are part of cycles the cycle collector breaks will be
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// collected by the next JS GC.
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//
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// If WantAllTraces() is false the cycle collector will not traverse roots
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// from category 1 or any JS objects held by them. Any JS objects they hold
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// will already be marked by the JS GC and will thus be colored black
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// themselves. Any C++ objects they hold will have a missing (untraversed)
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// edge from the JS object to the C++ object and so it will be marked black
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// too. This decreases the number of objects that the cycle collector has to
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// deal with.
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// To improve debugging, if WantAllTraces() is true all JS objects are
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// traversed.
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#include "mozilla/CycleCollectedJSRuntime.h"
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#include <algorithm>
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#include <utility>
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#include "js/Debug.h"
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#include "js/RealmOptions.h"
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#include "js/friend/DumpFunctions.h" // js::DumpHeap
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#include "js/GCAPI.h"
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#include "js/HeapAPI.h"
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#include "js/Object.h" // JS::GetClass, JS::GetCompartment, JS::GetPrivate
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#include "js/PropertyAndElement.h" // JS_DefineProperty
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#include "js/Warnings.h" // JS::SetWarningReporter
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#include "js/ShadowRealmCallbacks.h"
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#include "js/SliceBudget.h"
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#include "jsfriendapi.h"
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#include "mozilla/ArrayUtils.h"
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#include "mozilla/AutoRestore.h"
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#include "mozilla/CycleCollectedJSContext.h"
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#include "mozilla/DebuggerOnGCRunnable.h"
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#include "mozilla/MemoryReporting.h"
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#include "mozilla/PerfStats.h"
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#include "mozilla/ProfilerLabels.h"
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#include "mozilla/ProfilerMarkers.h"
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#include "mozilla/Sprintf.h"
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#include "mozilla/StaticPrefs_javascript.h"
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#include "mozilla/Telemetry.h"
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#include "mozilla/Unused.h"
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#include "mozilla/dom/AutoEntryScript.h"
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#include "mozilla/dom/DOMJSClass.h"
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#include "mozilla/dom/JSExecutionManager.h"
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#include "mozilla/dom/Promise.h"
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#include "mozilla/dom/PromiseBinding.h"
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#include "mozilla/dom/PromiseDebugging.h"
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#include "mozilla/dom/ScriptSettings.h"
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#include "mozilla/dom/ShadowRealmGlobalScope.h"
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#include "mozilla/dom/RegisterShadowRealmBindings.h"
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#include "nsContentUtils.h"
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#include "nsCycleCollectionNoteRootCallback.h"
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#include "nsCycleCollectionParticipant.h"
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#include "nsCycleCollector.h"
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#include "nsDOMJSUtils.h"
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#include "nsExceptionHandler.h"
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#include "nsJSUtils.h"
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#include "nsStringBuffer.h"
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#include "nsWrapperCache.h"
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#include "prenv.h"
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#if defined(XP_MACOSX)
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# include "nsMacUtilsImpl.h"
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#endif
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#include "nsThread.h"
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#include "nsThreadUtils.h"
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#include "xpcpublic.h"
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#ifdef NIGHTLY_BUILD
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// For performance reasons, we make the JS Dev Error Interceptor a Nightly-only
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// feature.
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# define MOZ_JS_DEV_ERROR_INTERCEPTOR = 1
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#endif // NIGHTLY_BUILD
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using namespace mozilla;
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using namespace mozilla::dom;
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namespace mozilla {
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struct DeferredFinalizeFunctionHolder {
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DeferredFinalizeFunction run;
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void* data;
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};
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class IncrementalFinalizeRunnable : public DiscardableRunnable {
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typedef AutoTArray<DeferredFinalizeFunctionHolder, 16> DeferredFinalizeArray;
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typedef CycleCollectedJSRuntime::DeferredFinalizerTable
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DeferredFinalizerTable;
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CycleCollectedJSRuntime* mRuntime;
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DeferredFinalizeArray mDeferredFinalizeFunctions;
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uint32_t mFinalizeFunctionToRun;
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bool mReleasing;
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static const PRTime SliceMillis = 5; /* ms */
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public:
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IncrementalFinalizeRunnable(CycleCollectedJSRuntime* aRt,
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DeferredFinalizerTable& aFinalizerTable);
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virtual ~IncrementalFinalizeRunnable();
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void ReleaseNow(bool aLimited);
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NS_DECL_NSIRUNNABLE
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};
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} // namespace mozilla
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struct NoteWeakMapChildrenTracer : public JS::CallbackTracer {
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NoteWeakMapChildrenTracer(JSRuntime* aRt,
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nsCycleCollectionNoteRootCallback& aCb)
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: JS::CallbackTracer(aRt, JS::TracerKind::Callback),
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mCb(aCb),
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mTracedAny(false),
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mMap(nullptr),
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mKey(nullptr),
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mKeyDelegate(nullptr) {}
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void onChild(JS::GCCellPtr aThing, const char* name) override;
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nsCycleCollectionNoteRootCallback& mCb;
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bool mTracedAny;
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JSObject* mMap;
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JS::GCCellPtr mKey;
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JSObject* mKeyDelegate;
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};
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void NoteWeakMapChildrenTracer::onChild(JS::GCCellPtr aThing,
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const char* name) {
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if (aThing.is<JSString>()) {
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return;
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}
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if (!JS::GCThingIsMarkedGrayInCC(aThing) && !mCb.WantAllTraces()) {
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return;
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}
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if (JS::IsCCTraceKind(aThing.kind())) {
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mCb.NoteWeakMapping(mMap, mKey, mKeyDelegate, aThing);
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mTracedAny = true;
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} else {
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JS::TraceChildren(this, aThing);
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}
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}
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struct NoteWeakMapsTracer : public js::WeakMapTracer {
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NoteWeakMapsTracer(JSRuntime* aRt, nsCycleCollectionNoteRootCallback& aCccb)
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: js::WeakMapTracer(aRt), mCb(aCccb), mChildTracer(aRt, aCccb) {}
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void trace(JSObject* aMap, JS::GCCellPtr aKey, JS::GCCellPtr aValue) override;
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nsCycleCollectionNoteRootCallback& mCb;
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NoteWeakMapChildrenTracer mChildTracer;
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};
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void NoteWeakMapsTracer::trace(JSObject* aMap, JS::GCCellPtr aKey,
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JS::GCCellPtr aValue) {
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// If nothing that could be held alive by this entry is marked gray, return.
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if ((!aKey || !JS::GCThingIsMarkedGrayInCC(aKey)) &&
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MOZ_LIKELY(!mCb.WantAllTraces())) {
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if (!aValue || !JS::GCThingIsMarkedGrayInCC(aValue) ||
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aValue.is<JSString>()) {
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return;
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}
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}
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// The cycle collector can only properly reason about weak maps if it can
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// reason about the liveness of their keys, which in turn requires that
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// the key can be represented in the cycle collector graph. All existing
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// uses of weak maps use either objects or scripts as keys, which are okay.
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MOZ_ASSERT(JS::IsCCTraceKind(aKey.kind()));
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// As an emergency fallback for non-debug builds, if the key is not
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// representable in the cycle collector graph, we treat it as marked. This
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// can cause leaks, but is preferable to ignoring the binding, which could
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// cause the cycle collector to free live objects.
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if (!JS::IsCCTraceKind(aKey.kind())) {
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aKey = nullptr;
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}
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JSObject* kdelegate = nullptr;
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if (aKey.is<JSObject>()) {
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kdelegate = js::UncheckedUnwrapWithoutExpose(&aKey.as<JSObject>());
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}
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if (JS::IsCCTraceKind(aValue.kind())) {
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mCb.NoteWeakMapping(aMap, aKey, kdelegate, aValue);
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} else {
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mChildTracer.mTracedAny = false;
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mChildTracer.mMap = aMap;
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mChildTracer.mKey = aKey;
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mChildTracer.mKeyDelegate = kdelegate;
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if (!aValue.is<JSString>()) {
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JS::TraceChildren(&mChildTracer, aValue);
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}
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// The delegate could hold alive the key, so report something to the CC
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// if we haven't already.
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if (!mChildTracer.mTracedAny && aKey && JS::GCThingIsMarkedGrayInCC(aKey) &&
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kdelegate) {
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mCb.NoteWeakMapping(aMap, aKey, kdelegate, nullptr);
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}
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}
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}
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// Report whether the key or value of a weak mapping entry are gray but need to
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// be marked black.
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static void ShouldWeakMappingEntryBeBlack(JSObject* aMap, JS::GCCellPtr aKey,
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JS::GCCellPtr aValue,
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bool* aKeyShouldBeBlack,
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bool* aValueShouldBeBlack) {
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*aKeyShouldBeBlack = false;
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*aValueShouldBeBlack = false;
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// If nothing that could be held alive by this entry is marked gray, return.
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bool keyMightNeedMarking = aKey && JS::GCThingIsMarkedGrayInCC(aKey);
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bool valueMightNeedMarking = aValue && JS::GCThingIsMarkedGrayInCC(aValue) &&
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aValue.kind() != JS::TraceKind::String;
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if (!keyMightNeedMarking && !valueMightNeedMarking) {
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return;
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}
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if (!JS::IsCCTraceKind(aKey.kind())) {
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aKey = nullptr;
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}
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if (keyMightNeedMarking && aKey.is<JSObject>()) {
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JSObject* kdelegate =
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js::UncheckedUnwrapWithoutExpose(&aKey.as<JSObject>());
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if (kdelegate && !JS::ObjectIsMarkedGray(kdelegate) &&
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(!aMap || !JS::ObjectIsMarkedGray(aMap))) {
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*aKeyShouldBeBlack = true;
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}
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}
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if (aValue && JS::GCThingIsMarkedGrayInCC(aValue) &&
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(!aKey || !JS::GCThingIsMarkedGrayInCC(aKey)) &&
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(!aMap || !JS::ObjectIsMarkedGray(aMap)) &&
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aValue.kind() != JS::TraceKind::Shape) {
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*aValueShouldBeBlack = true;
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}
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}
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struct FixWeakMappingGrayBitsTracer : public js::WeakMapTracer {
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explicit FixWeakMappingGrayBitsTracer(JSRuntime* aRt)
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: js::WeakMapTracer(aRt) {}
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void FixAll() {
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do {
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mAnyMarked = false;
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js::TraceWeakMaps(this);
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} while (mAnyMarked);
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}
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void trace(JSObject* aMap, JS::GCCellPtr aKey,
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JS::GCCellPtr aValue) override {
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bool keyShouldBeBlack;
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bool valueShouldBeBlack;
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ShouldWeakMappingEntryBeBlack(aMap, aKey, aValue, &keyShouldBeBlack,
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&valueShouldBeBlack);
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if (keyShouldBeBlack && JS::UnmarkGrayGCThingRecursively(aKey)) {
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mAnyMarked = true;
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}
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if (valueShouldBeBlack && JS::UnmarkGrayGCThingRecursively(aValue)) {
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mAnyMarked = true;
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}
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}
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MOZ_INIT_OUTSIDE_CTOR bool mAnyMarked;
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};
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#ifdef DEBUG
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// Check whether weak maps are marked correctly according to the logic above.
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struct CheckWeakMappingGrayBitsTracer : public js::WeakMapTracer {
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explicit CheckWeakMappingGrayBitsTracer(JSRuntime* aRt)
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: js::WeakMapTracer(aRt), mFailed(false) {}
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static bool Check(JSRuntime* aRt) {
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CheckWeakMappingGrayBitsTracer tracer(aRt);
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js::TraceWeakMaps(&tracer);
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return !tracer.mFailed;
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}
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void trace(JSObject* aMap, JS::GCCellPtr aKey,
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JS::GCCellPtr aValue) override {
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bool keyShouldBeBlack;
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bool valueShouldBeBlack;
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ShouldWeakMappingEntryBeBlack(aMap, aKey, aValue, &keyShouldBeBlack,
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&valueShouldBeBlack);
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if (keyShouldBeBlack) {
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fprintf(stderr, "Weak mapping key %p of map %p should be black\n",
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aKey.asCell(), aMap);
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mFailed = true;
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}
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if (valueShouldBeBlack) {
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fprintf(stderr, "Weak mapping value %p of map %p should be black\n",
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aValue.asCell(), aMap);
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mFailed = true;
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}
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}
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bool mFailed;
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};
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#endif // DEBUG
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static void CheckParticipatesInCycleCollection(JS::GCCellPtr aThing,
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const char* aName,
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void* aClosure) {
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bool* cycleCollectionEnabled = static_cast<bool*>(aClosure);
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if (*cycleCollectionEnabled) {
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return;
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}
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if (JS::IsCCTraceKind(aThing.kind()) && JS::GCThingIsMarkedGrayInCC(aThing)) {
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*cycleCollectionEnabled = true;
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}
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}
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NS_IMETHODIMP
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JSGCThingParticipant::TraverseNative(void* aPtr,
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nsCycleCollectionTraversalCallback& aCb) {
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auto runtime = reinterpret_cast<CycleCollectedJSRuntime*>(
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reinterpret_cast<char*>(this) -
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offsetof(CycleCollectedJSRuntime, mGCThingCycleCollectorGlobal));
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JS::GCCellPtr cellPtr(aPtr, JS::GCThingTraceKind(aPtr));
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runtime->TraverseGCThing(CycleCollectedJSRuntime::TRAVERSE_FULL, cellPtr,
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aCb);
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return NS_OK;
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}
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// NB: This is only used to initialize the participant in
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// CycleCollectedJSRuntime. It should never be used directly.
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static JSGCThingParticipant sGCThingCycleCollectorGlobal;
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NS_IMETHODIMP
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JSZoneParticipant::TraverseNative(void* aPtr,
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nsCycleCollectionTraversalCallback& aCb) {
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auto runtime = reinterpret_cast<CycleCollectedJSRuntime*>(
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reinterpret_cast<char*>(this) -
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offsetof(CycleCollectedJSRuntime, mJSZoneCycleCollectorGlobal));
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MOZ_ASSERT(!aCb.WantAllTraces());
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JS::Zone* zone = static_cast<JS::Zone*>(aPtr);
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runtime->TraverseZone(zone, aCb);
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return NS_OK;
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}
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struct TraversalTracer : public JS::CallbackTracer {
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TraversalTracer(JSRuntime* aRt, nsCycleCollectionTraversalCallback& aCb)
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: JS::CallbackTracer(aRt, JS::TracerKind::Callback,
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JS::TraceOptions(JS::WeakMapTraceAction::Skip,
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JS::WeakEdgeTraceAction::Trace)),
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mCb(aCb) {}
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void onChild(JS::GCCellPtr aThing, const char* name) override;
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nsCycleCollectionTraversalCallback& mCb;
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};
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void TraversalTracer::onChild(JS::GCCellPtr aThing, const char* name) {
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// Checking strings and symbols for being gray is rather slow, and we don't
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|
// need either of them for the cycle collector.
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if (aThing.is<JSString>() || aThing.is<JS::Symbol>()) {
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return;
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}
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// Don't traverse non-gray objects, unless we want all traces.
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if (!JS::GCThingIsMarkedGrayInCC(aThing) && !mCb.WantAllTraces()) {
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return;
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}
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/*
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* This function needs to be careful to avoid stack overflow. Normally, when
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* IsCCTraceKind is true, the recursion terminates immediately as we just add
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* |thing| to the CC graph. So overflow is only possible when there are long
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* or cyclic chains of non-IsCCTraceKind GC things. Places where this can
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* occur use special APIs to handle such chains iteratively.
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*/
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if (JS::IsCCTraceKind(aThing.kind())) {
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if (MOZ_UNLIKELY(mCb.WantDebugInfo())) {
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char buffer[200];
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context().getEdgeName(name, buffer, sizeof(buffer));
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mCb.NoteNextEdgeName(buffer);
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}
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mCb.NoteJSChild(aThing);
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return;
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}
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// Allow re-use of this tracer inside trace callback.
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|
JS::AutoClearTracingContext actc(this);
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if (aThing.is<js::Shape>()) {
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// The maximum depth of traversal when tracing a Shape is unbounded, due to
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// the parent pointers on the shape.
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JS_TraceShapeCycleCollectorChildren(this, aThing);
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} else {
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JS::TraceChildren(this, aThing);
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}
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}
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|
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/*
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* The cycle collection participant for a Zone is intended to produce the same
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* results as if all of the gray GCthings in a zone were merged into a single
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* node, except for self-edges. This avoids the overhead of representing all of
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* the GCthings in the zone in the cycle collector graph, which should be much
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* faster if many of the GCthings in the zone are gray.
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*
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* Zone merging should not always be used, because it is a conservative
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* approximation of the true cycle collector graph that can incorrectly identify
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* some garbage objects as being live. For instance, consider two cycles that
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* pass through a zone, where one is garbage and the other is live. If we merge
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* the entire zone, the cycle collector will think that both are alive.
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*
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* We don't have to worry about losing track of a garbage cycle, because any
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* such garbage cycle incorrectly identified as live must contain at least one
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* C++ to JS edge, and XPConnect will always add the C++ object to the CC graph.
|
|
* (This is in contrast to pure C++ garbage cycles, which must always be
|
|
* properly identified, because we clear the purple buffer during every CC,
|
|
* which may contain the last reference to a garbage cycle.)
|
|
*/
|
|
|
|
// NB: This is only used to initialize the participant in
|
|
// CycleCollectedJSRuntime. It should never be used directly.
|
|
static const JSZoneParticipant sJSZoneCycleCollectorGlobal;
|
|
|
|
static void JSObjectsTenuredCb(JSContext* aContext, void* aData) {
|
|
static_cast<CycleCollectedJSRuntime*>(aData)->JSObjectsTenured();
|
|
}
|
|
|
|
static void MozCrashWarningReporter(JSContext*, JSErrorReport*) {
|
|
MOZ_CRASH("Why is someone touching JSAPI without an AutoJSAPI?");
|
|
}
|
|
|
|
JSHolderMap::Entry::Entry() : Entry(nullptr, nullptr, nullptr) {}
|
|
|
|
JSHolderMap::Entry::Entry(void* aHolder, nsScriptObjectTracer* aTracer,
|
|
JS::Zone* aZone)
|
|
: mHolder(aHolder),
|
|
mTracer(aTracer)
|
|
#ifdef DEBUG
|
|
,
|
|
mZone(aZone)
|
|
#endif
|
|
{
|
|
}
|
|
|
|
void JSHolderMap::EntryVectorIter::Settle() {
|
|
if (Done()) {
|
|
return;
|
|
}
|
|
|
|
Entry* entry = &mIter.Get();
|
|
|
|
// If the entry has been cleared, remove it and shrink the vector.
|
|
if (!entry->mHolder && !mHolderMap.RemoveEntry(mVector, entry)) {
|
|
// We removed the last entry, so reset the iterator to an empty one.
|
|
mIter = EntryVector().Iter();
|
|
MOZ_ASSERT(Done());
|
|
}
|
|
}
|
|
|
|
JSHolderMap::Iter::Iter(JSHolderMap& aMap, WhichHolders aWhich)
|
|
: mHolderMap(aMap), mIter(aMap, aMap.mAnyZoneJSHolders) {
|
|
MOZ_RELEASE_ASSERT(!mHolderMap.mHasIterator);
|
|
mHolderMap.mHasIterator = true;
|
|
|
|
// Populate vector of zones to iterate after the any-zone holders.
|
|
for (auto i = aMap.mPerZoneJSHolders.iter(); !i.done(); i.next()) {
|
|
JS::Zone* zone = i.get().key();
|
|
if (aWhich == AllHolders || JS::NeedGrayRootsForZone(i.get().key())) {
|
|
MOZ_ALWAYS_TRUE(mZones.append(zone));
|
|
}
|
|
}
|
|
|
|
Settle();
|
|
}
|
|
|
|
void JSHolderMap::Iter::Settle() {
|
|
while (mIter.Done()) {
|
|
if (mZone && mIter.Vector().IsEmpty()) {
|
|
mHolderMap.mPerZoneJSHolders.remove(mZone);
|
|
}
|
|
|
|
mZone = nullptr;
|
|
if (mZones.empty()) {
|
|
break;
|
|
}
|
|
|
|
mZone = mZones.popCopy();
|
|
EntryVector& vector = *mHolderMap.mPerZoneJSHolders.lookup(mZone)->value();
|
|
new (&mIter) EntryVectorIter(mHolderMap, vector);
|
|
}
|
|
}
|
|
|
|
void JSHolderMap::Iter::UpdateForRemovals() {
|
|
mIter.Settle();
|
|
Settle();
|
|
}
|
|
|
|
JSHolderMap::JSHolderMap() : mJSHolderMap(256) {}
|
|
|
|
bool JSHolderMap::RemoveEntry(EntryVector& aJSHolders, Entry* aEntry) {
|
|
MOZ_ASSERT(aEntry);
|
|
MOZ_ASSERT(!aEntry->mHolder);
|
|
|
|
// Remove all dead entries from the end of the vector.
|
|
while (!aJSHolders.GetLast().mHolder && &aJSHolders.GetLast() != aEntry) {
|
|
aJSHolders.PopLast();
|
|
}
|
|
|
|
// Swap the element we want to remove with the last one and update the hash
|
|
// table.
|
|
Entry* lastEntry = &aJSHolders.GetLast();
|
|
if (aEntry != lastEntry) {
|
|
MOZ_ASSERT(lastEntry->mHolder);
|
|
*aEntry = *lastEntry;
|
|
MOZ_ASSERT(mJSHolderMap.has(aEntry->mHolder));
|
|
MOZ_ALWAYS_TRUE(mJSHolderMap.put(aEntry->mHolder, aEntry));
|
|
}
|
|
|
|
aJSHolders.PopLast();
|
|
|
|
// Return whether aEntry is still in the vector.
|
|
return aEntry != lastEntry;
|
|
}
|
|
|
|
bool JSHolderMap::Has(void* aHolder) const { return mJSHolderMap.has(aHolder); }
|
|
|
|
nsScriptObjectTracer* JSHolderMap::Get(void* aHolder) const {
|
|
auto ptr = mJSHolderMap.lookup(aHolder);
|
|
if (!ptr) {
|
|
return nullptr;
|
|
}
|
|
|
|
Entry* entry = ptr->value();
|
|
MOZ_ASSERT(entry->mHolder == aHolder);
|
|
return entry->mTracer;
|
|
}
|
|
|
|
nsScriptObjectTracer* JSHolderMap::Extract(void* aHolder) {
|
|
MOZ_ASSERT(aHolder);
|
|
|
|
auto ptr = mJSHolderMap.lookup(aHolder);
|
|
if (!ptr) {
|
|
return nullptr;
|
|
}
|
|
|
|
Entry* entry = ptr->value();
|
|
MOZ_ASSERT(entry->mHolder == aHolder);
|
|
nsScriptObjectTracer* tracer = entry->mTracer;
|
|
|
|
// Clear the entry's contents. It will be removed the next time iteration
|
|
// visits this entry.
|
|
*entry = Entry();
|
|
|
|
mJSHolderMap.remove(ptr);
|
|
|
|
return tracer;
|
|
}
|
|
|
|
void JSHolderMap::Put(void* aHolder, nsScriptObjectTracer* aTracer,
|
|
JS::Zone* aZone) {
|
|
MOZ_ASSERT(aHolder);
|
|
MOZ_ASSERT(aTracer);
|
|
|
|
// Don't associate multi-zone holders with a zone, even if one is supplied.
|
|
if (!aTracer->IsSingleZoneJSHolder()) {
|
|
aZone = nullptr;
|
|
}
|
|
|
|
auto ptr = mJSHolderMap.lookupForAdd(aHolder);
|
|
if (ptr) {
|
|
Entry* entry = ptr->value();
|
|
#ifdef DEBUG
|
|
MOZ_ASSERT(entry->mHolder == aHolder);
|
|
MOZ_ASSERT(entry->mTracer == aTracer,
|
|
"Don't call HoldJSObjects in superclass ctors");
|
|
if (aZone) {
|
|
if (entry->mZone) {
|
|
MOZ_ASSERT(entry->mZone == aZone);
|
|
} else {
|
|
entry->mZone = aZone;
|
|
}
|
|
}
|
|
#endif
|
|
entry->mTracer = aTracer;
|
|
return;
|
|
}
|
|
|
|
EntryVector* vector = &mAnyZoneJSHolders;
|
|
if (aZone) {
|
|
auto ptr = mPerZoneJSHolders.lookupForAdd(aZone);
|
|
if (!ptr) {
|
|
MOZ_ALWAYS_TRUE(
|
|
mPerZoneJSHolders.add(ptr, aZone, MakeUnique<EntryVector>()));
|
|
}
|
|
vector = ptr->value().get();
|
|
}
|
|
|
|
vector->InfallibleAppend(Entry{aHolder, aTracer, aZone});
|
|
MOZ_ALWAYS_TRUE(mJSHolderMap.add(ptr, aHolder, &vector->GetLast()));
|
|
}
|
|
|
|
size_t JSHolderMap::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
|
|
size_t n = 0;
|
|
|
|
// We're deliberately not measuring anything hanging off the entries in
|
|
// mJSHolders.
|
|
n += mJSHolderMap.shallowSizeOfExcludingThis(aMallocSizeOf);
|
|
n += mAnyZoneJSHolders.SizeOfExcludingThis(aMallocSizeOf);
|
|
n += mPerZoneJSHolders.shallowSizeOfExcludingThis(aMallocSizeOf);
|
|
for (auto i = mPerZoneJSHolders.iter(); !i.done(); i.next()) {
|
|
n += i.get().value()->SizeOfExcludingThis(aMallocSizeOf);
|
|
}
|
|
|
|
return n;
|
|
}
|
|
|
|
static bool InitializeShadowRealm(JSContext* aCx,
|
|
JS::Handle<JSObject*> aGlobal) {
|
|
MOZ_ASSERT(StaticPrefs::javascript_options_experimental_shadow_realms());
|
|
|
|
JSAutoRealm ar(aCx, aGlobal);
|
|
return dom::RegisterShadowRealmBindings(aCx, aGlobal);
|
|
}
|
|
|
|
CycleCollectedJSRuntime::CycleCollectedJSRuntime(JSContext* aCx)
|
|
: mContext(nullptr),
|
|
mGCThingCycleCollectorGlobal(sGCThingCycleCollectorGlobal),
|
|
mJSZoneCycleCollectorGlobal(sJSZoneCycleCollectorGlobal),
|
|
mJSRuntime(JS_GetRuntime(aCx)),
|
|
mHasPendingIdleGCTask(false),
|
|
mPrevGCSliceCallback(nullptr),
|
|
mOutOfMemoryState(OOMState::OK),
|
|
mLargeAllocationFailureState(OOMState::OK)
|
|
#ifdef DEBUG
|
|
,
|
|
mShutdownCalled(false)
|
|
#endif
|
|
{
|
|
MOZ_COUNT_CTOR(CycleCollectedJSRuntime);
|
|
MOZ_ASSERT(aCx);
|
|
MOZ_ASSERT(mJSRuntime);
|
|
|
|
#if defined(XP_MACOSX)
|
|
if (!XRE_IsParentProcess()) {
|
|
nsMacUtilsImpl::EnableTCSMIfAvailable();
|
|
}
|
|
#endif
|
|
|
|
if (!JS_AddExtraGCRootsTracer(aCx, TraceBlackJS, this)) {
|
|
MOZ_CRASH("JS_AddExtraGCRootsTracer failed");
|
|
}
|
|
JS_SetGrayGCRootsTracer(aCx, TraceGrayJS, this);
|
|
JS_SetGCCallback(aCx, GCCallback, this);
|
|
mPrevGCSliceCallback = JS::SetGCSliceCallback(aCx, GCSliceCallback);
|
|
|
|
if (NS_IsMainThread()) {
|
|
// We would like to support all threads here, but the way timeline consumers
|
|
// are set up currently, you can either add a marker for one specific
|
|
// docshell, or for every consumer globally. We would like to add a marker
|
|
// for every consumer observing anything on this thread, but that is not
|
|
// currently possible. For now, add global markers only when we are on the
|
|
// main thread, since the UI for this tracing data only displays data
|
|
// relevant to the main-thread.
|
|
JS::AddGCNurseryCollectionCallback(aCx, GCNurseryCollectionCallback,
|
|
nullptr);
|
|
}
|
|
|
|
JS_SetObjectsTenuredCallback(aCx, JSObjectsTenuredCb, this);
|
|
JS::SetOutOfMemoryCallback(aCx, OutOfMemoryCallback, this);
|
|
JS::SetWaitCallback(mJSRuntime, BeforeWaitCallback, AfterWaitCallback,
|
|
sizeof(dom::AutoYieldJSThreadExecution));
|
|
JS::SetWarningReporter(aCx, MozCrashWarningReporter);
|
|
JS::SetShadowRealmInitializeGlobalCallback(aCx, InitializeShadowRealm);
|
|
JS::SetShadowRealmGlobalCreationCallback(aCx, dom::NewShadowRealmGlobal);
|
|
|
|
js::AutoEnterOOMUnsafeRegion::setAnnotateOOMAllocationSizeCallback(
|
|
CrashReporter::AnnotateOOMAllocationSize);
|
|
|
|
static js::DOMCallbacks DOMcallbacks = {InstanceClassHasProtoAtDepth};
|
|
SetDOMCallbacks(aCx, &DOMcallbacks);
|
|
js::SetScriptEnvironmentPreparer(aCx, &mEnvironmentPreparer);
|
|
|
|
JS::dbg::SetDebuggerMallocSizeOf(aCx, moz_malloc_size_of);
|
|
|
|
#ifdef MOZ_JS_DEV_ERROR_INTERCEPTOR
|
|
JS_SetErrorInterceptorCallback(mJSRuntime, &mErrorInterceptor);
|
|
#endif // MOZ_JS_DEV_ERROR_INTERCEPTOR
|
|
|
|
JS_SetDestroyZoneCallback(aCx, OnZoneDestroyed);
|
|
}
|
|
|
|
#ifdef NS_BUILD_REFCNT_LOGGING
|
|
class JSLeakTracer : public JS::CallbackTracer {
|
|
public:
|
|
explicit JSLeakTracer(JSRuntime* aRuntime)
|
|
: JS::CallbackTracer(aRuntime, JS::TracerKind::Callback,
|
|
JS::WeakMapTraceAction::TraceKeysAndValues) {}
|
|
|
|
private:
|
|
void onChild(JS::GCCellPtr thing, const char* name) override {
|
|
const char* kindName = JS::GCTraceKindToAscii(thing.kind());
|
|
size_t size = JS::GCTraceKindSize(thing.kind());
|
|
MOZ_LOG_CTOR(thing.asCell(), kindName, size);
|
|
}
|
|
};
|
|
#endif
|
|
|
|
void CycleCollectedJSRuntime::Shutdown(JSContext* aCx) {
|
|
#ifdef MOZ_JS_DEV_ERROR_INTERCEPTOR
|
|
mErrorInterceptor.Shutdown(mJSRuntime);
|
|
#endif // MOZ_JS_DEV_ERROR_INTERCEPTOR
|
|
|
|
// There should not be any roots left to trace at this point. Ensure any that
|
|
// remain are flagged as leaks.
|
|
#ifdef NS_BUILD_REFCNT_LOGGING
|
|
JSLeakTracer tracer(Runtime());
|
|
TraceNativeBlackRoots(&tracer);
|
|
TraceAllNativeGrayRoots(&tracer);
|
|
#endif
|
|
|
|
#ifdef DEBUG
|
|
mShutdownCalled = true;
|
|
#endif
|
|
|
|
JS_SetDestroyZoneCallback(aCx, nullptr);
|
|
|
|
if (NS_IsMainThread()) {
|
|
JS::RemoveGCNurseryCollectionCallback(aCx, GCNurseryCollectionCallback,
|
|
nullptr);
|
|
}
|
|
}
|
|
|
|
CycleCollectedJSRuntime::~CycleCollectedJSRuntime() {
|
|
MOZ_COUNT_DTOR(CycleCollectedJSRuntime);
|
|
MOZ_ASSERT(!mDeferredFinalizerTable.Count());
|
|
MOZ_ASSERT(!mFinalizeRunnable);
|
|
MOZ_ASSERT(mShutdownCalled);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::SetContext(CycleCollectedJSContext* aContext) {
|
|
MOZ_ASSERT(!mContext || !aContext, "Don't replace the context!");
|
|
mContext = aContext;
|
|
}
|
|
|
|
size_t CycleCollectedJSRuntime::SizeOfExcludingThis(
|
|
MallocSizeOf aMallocSizeOf) const {
|
|
return mJSHolders.SizeOfExcludingThis(aMallocSizeOf);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::UnmarkSkippableJSHolders() {
|
|
for (JSHolderMap::Iter entry(mJSHolders); !entry.Done(); entry.Next()) {
|
|
entry->mTracer->CanSkip(entry->mHolder, true);
|
|
}
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::DescribeGCThing(
|
|
bool aIsMarked, JS::GCCellPtr aThing,
|
|
nsCycleCollectionTraversalCallback& aCb) const {
|
|
if (!aCb.WantDebugInfo()) {
|
|
aCb.DescribeGCedNode(aIsMarked, "JS Object");
|
|
return;
|
|
}
|
|
|
|
char name[72];
|
|
uint64_t compartmentAddress = 0;
|
|
if (aThing.is<JSObject>()) {
|
|
JSObject* obj = &aThing.as<JSObject>();
|
|
compartmentAddress = (uint64_t)JS::GetCompartment(obj);
|
|
const JSClass* clasp = JS::GetClass(obj);
|
|
|
|
// Give the subclass a chance to do something
|
|
if (DescribeCustomObjects(obj, clasp, name)) {
|
|
// Nothing else to do!
|
|
} else if (js::IsFunctionObject(obj)) {
|
|
JSFunction* fun = JS_GetObjectFunction(obj);
|
|
JSString* str = JS_GetMaybePartialFunctionDisplayId(fun);
|
|
if (str) {
|
|
JSLinearString* linear = JS_ASSERT_STRING_IS_LINEAR(str);
|
|
nsAutoString chars;
|
|
AssignJSLinearString(chars, linear);
|
|
NS_ConvertUTF16toUTF8 fname(chars);
|
|
SprintfLiteral(name, "JS Object (Function - %s)", fname.get());
|
|
} else {
|
|
SprintfLiteral(name, "JS Object (Function)");
|
|
}
|
|
} else {
|
|
SprintfLiteral(name, "JS Object (%s)", clasp->name);
|
|
}
|
|
} else {
|
|
SprintfLiteral(name, "%s", JS::GCTraceKindToAscii(aThing.kind()));
|
|
}
|
|
|
|
// Disable printing global for objects while we figure out ObjShrink fallout.
|
|
aCb.DescribeGCedNode(aIsMarked, name, compartmentAddress);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::NoteGCThingJSChildren(
|
|
JS::GCCellPtr aThing, nsCycleCollectionTraversalCallback& aCb) const {
|
|
TraversalTracer trc(mJSRuntime, aCb);
|
|
JS::TraceChildren(&trc, aThing);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::NoteGCThingXPCOMChildren(
|
|
const JSClass* aClasp, JSObject* aObj,
|
|
nsCycleCollectionTraversalCallback& aCb) const {
|
|
MOZ_ASSERT(aClasp);
|
|
MOZ_ASSERT(aClasp == JS::GetClass(aObj));
|
|
|
|
JS::Rooted<JSObject*> obj(RootingCx(), aObj);
|
|
|
|
if (NoteCustomGCThingXPCOMChildren(aClasp, obj, aCb)) {
|
|
// Nothing else to do!
|
|
return;
|
|
}
|
|
|
|
// XXX This test does seem fragile, we should probably allowlist classes
|
|
// that do hold a strong reference, but that might not be possible.
|
|
if (aClasp->slot0IsISupports()) {
|
|
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(aCb, "JS::GetObjectISupports(obj)");
|
|
aCb.NoteXPCOMChild(JS::GetObjectISupports<nsISupports>(obj));
|
|
return;
|
|
}
|
|
|
|
const DOMJSClass* domClass = GetDOMClass(aClasp);
|
|
if (domClass) {
|
|
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(aCb, "UnwrapDOMObject(obj)");
|
|
// It's possible that our object is an unforgeable holder object, in
|
|
// which case it doesn't actually have a C++ DOM object associated with
|
|
// it. Use UnwrapPossiblyNotInitializedDOMObject, which produces null in
|
|
// that case, since NoteXPCOMChild/NoteNativeChild are null-safe.
|
|
if (domClass->mDOMObjectIsISupports) {
|
|
aCb.NoteXPCOMChild(
|
|
UnwrapPossiblyNotInitializedDOMObject<nsISupports>(obj));
|
|
} else if (domClass->mParticipant) {
|
|
aCb.NoteNativeChild(UnwrapPossiblyNotInitializedDOMObject<void>(obj),
|
|
domClass->mParticipant);
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (IsRemoteObjectProxy(obj)) {
|
|
auto handler =
|
|
static_cast<const RemoteObjectProxyBase*>(js::GetProxyHandler(obj));
|
|
return handler->NoteChildren(obj, aCb);
|
|
}
|
|
|
|
JS::Value value = js::MaybeGetScriptPrivate(obj);
|
|
if (!value.isUndefined()) {
|
|
aCb.NoteXPCOMChild(static_cast<nsISupports*>(value.toPrivate()));
|
|
}
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::TraverseGCThing(
|
|
TraverseSelect aTs, JS::GCCellPtr aThing,
|
|
nsCycleCollectionTraversalCallback& aCb) {
|
|
bool isMarkedGray = JS::GCThingIsMarkedGrayInCC(aThing);
|
|
|
|
if (aTs == TRAVERSE_FULL) {
|
|
DescribeGCThing(!isMarkedGray, aThing, aCb);
|
|
}
|
|
|
|
// If this object is alive, then all of its children are alive. For JS
|
|
// objects, the black-gray invariant ensures the children are also marked
|
|
// black. For C++ objects, the ref count from this object will keep them
|
|
// alive. Thus we don't need to trace our children, unless we are debugging
|
|
// using WantAllTraces.
|
|
if (!isMarkedGray && !aCb.WantAllTraces()) {
|
|
return;
|
|
}
|
|
|
|
if (aTs == TRAVERSE_FULL) {
|
|
NoteGCThingJSChildren(aThing, aCb);
|
|
}
|
|
|
|
if (aThing.is<JSObject>()) {
|
|
JSObject* obj = &aThing.as<JSObject>();
|
|
NoteGCThingXPCOMChildren(JS::GetClass(obj), obj, aCb);
|
|
}
|
|
}
|
|
|
|
struct TraverseObjectShimClosure {
|
|
nsCycleCollectionTraversalCallback& cb;
|
|
CycleCollectedJSRuntime* self;
|
|
};
|
|
|
|
void CycleCollectedJSRuntime::TraverseZone(
|
|
JS::Zone* aZone, nsCycleCollectionTraversalCallback& aCb) {
|
|
/*
|
|
* We treat the zone as being gray. We handle non-gray GCthings in the
|
|
* zone by not reporting their children to the CC. The black-gray invariant
|
|
* ensures that any JS children will also be non-gray, and thus don't need to
|
|
* be added to the graph. For C++ children, not representing the edge from the
|
|
* non-gray JS GCthings to the C++ object will keep the child alive.
|
|
*
|
|
* We don't allow zone merging in a WantAllTraces CC, because then these
|
|
* assumptions don't hold.
|
|
*/
|
|
aCb.DescribeGCedNode(false, "JS Zone");
|
|
|
|
/*
|
|
* Every JS child of everything in the zone is either in the zone
|
|
* or is a cross-compartment wrapper. In the former case, we don't need to
|
|
* represent these edges in the CC graph because JS objects are not ref
|
|
* counted. In the latter case, the JS engine keeps a map of these wrappers,
|
|
* which we iterate over. Edges between compartments in the same zone will add
|
|
* unnecessary loop edges to the graph (bug 842137).
|
|
*/
|
|
TraversalTracer trc(mJSRuntime, aCb);
|
|
js::TraceGrayWrapperTargets(&trc, aZone);
|
|
|
|
/*
|
|
* To find C++ children of things in the zone, we scan every JS Object in
|
|
* the zone. Only JS Objects can have C++ children.
|
|
*/
|
|
TraverseObjectShimClosure closure = {aCb, this};
|
|
js::IterateGrayObjects(aZone, TraverseObjectShim, &closure);
|
|
}
|
|
|
|
/* static */
|
|
void CycleCollectedJSRuntime::TraverseObjectShim(
|
|
void* aData, JS::GCCellPtr aThing, const JS::AutoRequireNoGC& nogc) {
|
|
TraverseObjectShimClosure* closure =
|
|
static_cast<TraverseObjectShimClosure*>(aData);
|
|
|
|
MOZ_ASSERT(aThing.is<JSObject>());
|
|
closure->self->TraverseGCThing(CycleCollectedJSRuntime::TRAVERSE_CPP, aThing,
|
|
closure->cb);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::TraverseNativeRoots(
|
|
nsCycleCollectionNoteRootCallback& aCb) {
|
|
// NB: This is here just to preserve the existing XPConnect order. I doubt it
|
|
// would hurt to do this after the JS holders.
|
|
TraverseAdditionalNativeRoots(aCb);
|
|
|
|
for (JSHolderMap::Iter entry(mJSHolders); !entry.Done(); entry.Next()) {
|
|
void* holder = entry->mHolder;
|
|
nsScriptObjectTracer* tracer = entry->mTracer;
|
|
|
|
bool noteRoot = false;
|
|
if (MOZ_UNLIKELY(aCb.WantAllTraces())) {
|
|
noteRoot = true;
|
|
} else {
|
|
tracer->Trace(holder,
|
|
TraceCallbackFunc(CheckParticipatesInCycleCollection),
|
|
¬eRoot);
|
|
}
|
|
|
|
if (noteRoot) {
|
|
aCb.NoteNativeRoot(holder, tracer);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* static */
|
|
void CycleCollectedJSRuntime::TraceBlackJS(JSTracer* aTracer, void* aData) {
|
|
CycleCollectedJSRuntime* self = static_cast<CycleCollectedJSRuntime*>(aData);
|
|
|
|
self->TraceNativeBlackRoots(aTracer);
|
|
}
|
|
|
|
/* static */
|
|
bool CycleCollectedJSRuntime::TraceGrayJS(JSTracer* aTracer,
|
|
js::SliceBudget& budget,
|
|
void* aData) {
|
|
CycleCollectedJSRuntime* self = static_cast<CycleCollectedJSRuntime*>(aData);
|
|
|
|
// Mark these roots as gray so the CC can walk them later.
|
|
|
|
JSHolderMap::WhichHolders which = JSHolderMap::AllHolders;
|
|
|
|
// Only trace holders in collecting zones when marking, except if we are
|
|
// collecting the atoms zone since any holder may point into that zone.
|
|
if (aTracer->isMarkingTracer() &&
|
|
!JS::AtomsZoneIsCollecting(self->Runtime())) {
|
|
which = JSHolderMap::HoldersRequiredForGrayMarking;
|
|
}
|
|
|
|
return self->TraceNativeGrayRoots(aTracer, which, budget);
|
|
}
|
|
|
|
/* static */
|
|
void CycleCollectedJSRuntime::GCCallback(JSContext* aContext,
|
|
JSGCStatus aStatus,
|
|
JS::GCReason aReason, void* aData) {
|
|
CycleCollectedJSRuntime* self = static_cast<CycleCollectedJSRuntime*>(aData);
|
|
|
|
MOZ_ASSERT(CycleCollectedJSContext::Get()->Context() == aContext);
|
|
MOZ_ASSERT(CycleCollectedJSContext::Get()->Runtime() == self);
|
|
|
|
self->OnGC(aContext, aStatus, aReason);
|
|
}
|
|
|
|
/* static */
|
|
void CycleCollectedJSRuntime::GCSliceCallback(JSContext* aContext,
|
|
JS::GCProgress aProgress,
|
|
const JS::GCDescription& aDesc) {
|
|
CycleCollectedJSRuntime* self = CycleCollectedJSRuntime::Get();
|
|
MOZ_ASSERT(CycleCollectedJSContext::Get()->Context() == aContext);
|
|
|
|
if (profiler_thread_is_being_profiled_for_markers()) {
|
|
if (aProgress == JS::GC_CYCLE_END) {
|
|
struct GCMajorMarker {
|
|
static constexpr mozilla::Span<const char> MarkerTypeName() {
|
|
return mozilla::MakeStringSpan("GCMajor");
|
|
}
|
|
static void StreamJSONMarkerData(
|
|
mozilla::baseprofiler::SpliceableJSONWriter& aWriter,
|
|
const mozilla::ProfilerString8View& aTimingJSON) {
|
|
if (aTimingJSON.Length() != 0) {
|
|
aWriter.SplicedJSONProperty("timings", aTimingJSON);
|
|
} else {
|
|
aWriter.NullProperty("timings");
|
|
}
|
|
}
|
|
static mozilla::MarkerSchema MarkerTypeDisplay() {
|
|
using MS = mozilla::MarkerSchema;
|
|
MS schema{MS::Location::MarkerChart, MS::Location::MarkerTable,
|
|
MS::Location::TimelineMemory};
|
|
schema.AddStaticLabelValue(
|
|
"Description",
|
|
"Summary data for an entire major GC, encompassing a set of "
|
|
"incremental slices. The main thread is not blocked for the "
|
|
"entire major GC interval, only for the individual slices.");
|
|
// No display instructions here, there is special handling in the
|
|
// front-end.
|
|
return schema;
|
|
}
|
|
};
|
|
|
|
profiler_add_marker("GCMajor", baseprofiler::category::GCCC,
|
|
MarkerTiming::Interval(aDesc.startTime(aContext),
|
|
aDesc.endTime(aContext)),
|
|
GCMajorMarker{},
|
|
ProfilerString8View::WrapNullTerminatedString(
|
|
aDesc.formatJSONProfiler(aContext).get()));
|
|
} else if (aProgress == JS::GC_SLICE_END) {
|
|
struct GCSliceMarker {
|
|
static constexpr mozilla::Span<const char> MarkerTypeName() {
|
|
return mozilla::MakeStringSpan("GCSlice");
|
|
}
|
|
static void StreamJSONMarkerData(
|
|
mozilla::baseprofiler::SpliceableJSONWriter& aWriter,
|
|
const mozilla::ProfilerString8View& aTimingJSON) {
|
|
if (aTimingJSON.Length() != 0) {
|
|
aWriter.SplicedJSONProperty("timings", aTimingJSON);
|
|
} else {
|
|
aWriter.NullProperty("timings");
|
|
}
|
|
}
|
|
static mozilla::MarkerSchema MarkerTypeDisplay() {
|
|
using MS = mozilla::MarkerSchema;
|
|
MS schema{MS::Location::MarkerChart, MS::Location::MarkerTable,
|
|
MS::Location::TimelineMemory};
|
|
schema.AddStaticLabelValue(
|
|
"Description",
|
|
"One slice of an incremental garbage collection (GC). The main "
|
|
"thread is blocked during this time.");
|
|
// No display instructions here, there is special handling in the
|
|
// front-end.
|
|
return schema;
|
|
}
|
|
};
|
|
|
|
profiler_add_marker("GCSlice", baseprofiler::category::GCCC,
|
|
MarkerTiming::Interval(aDesc.lastSliceStart(aContext),
|
|
aDesc.lastSliceEnd(aContext)),
|
|
GCSliceMarker{},
|
|
ProfilerString8View::WrapNullTerminatedString(
|
|
aDesc.sliceToJSONProfiler(aContext).get()));
|
|
}
|
|
}
|
|
|
|
if (aProgress == JS::GC_CYCLE_END &&
|
|
JS::dbg::FireOnGarbageCollectionHookRequired(aContext)) {
|
|
JS::GCReason reason = aDesc.reason_;
|
|
Unused << NS_WARN_IF(
|
|
NS_FAILED(DebuggerOnGCRunnable::Enqueue(aContext, aDesc)) &&
|
|
reason != JS::GCReason::SHUTDOWN_CC &&
|
|
reason != JS::GCReason::DESTROY_RUNTIME &&
|
|
reason != JS::GCReason::XPCONNECT_SHUTDOWN);
|
|
}
|
|
|
|
if (self->mPrevGCSliceCallback) {
|
|
self->mPrevGCSliceCallback(aContext, aProgress, aDesc);
|
|
}
|
|
}
|
|
|
|
/* static */
|
|
void CycleCollectedJSRuntime::GCNurseryCollectionCallback(
|
|
JSContext* aContext, JS::GCNurseryProgress aProgress, JS::GCReason aReason,
|
|
void* data) {
|
|
CycleCollectedJSRuntime* self = CycleCollectedJSRuntime::Get();
|
|
MOZ_ASSERT(CycleCollectedJSContext::Get()->Context() == aContext);
|
|
MOZ_ASSERT(NS_IsMainThread());
|
|
|
|
TimeStamp now = TimeStamp::Now();
|
|
if (aProgress == JS::GCNurseryProgress::GC_NURSERY_COLLECTION_START) {
|
|
self->mLatestNurseryCollectionStart = now;
|
|
} else if (aProgress == JS::GCNurseryProgress::GC_NURSERY_COLLECTION_END) {
|
|
PerfStats::RecordMeasurement(PerfStats::Metric::MinorGC,
|
|
now - self->mLatestNurseryCollectionStart);
|
|
}
|
|
|
|
if (aProgress == JS::GCNurseryProgress::GC_NURSERY_COLLECTION_END &&
|
|
profiler_thread_is_being_profiled_for_markers()) {
|
|
struct GCMinorMarker {
|
|
static constexpr mozilla::Span<const char> MarkerTypeName() {
|
|
return mozilla::MakeStringSpan("GCMinor");
|
|
}
|
|
static void StreamJSONMarkerData(
|
|
mozilla::baseprofiler::SpliceableJSONWriter& aWriter,
|
|
const mozilla::ProfilerString8View& aTimingJSON) {
|
|
if (aTimingJSON.Length() != 0) {
|
|
aWriter.SplicedJSONProperty("nursery", aTimingJSON);
|
|
} else {
|
|
aWriter.NullProperty("nursery");
|
|
}
|
|
}
|
|
static mozilla::MarkerSchema MarkerTypeDisplay() {
|
|
using MS = mozilla::MarkerSchema;
|
|
MS schema{MS::Location::MarkerChart, MS::Location::MarkerTable,
|
|
MS::Location::TimelineMemory};
|
|
schema.AddStaticLabelValue(
|
|
"Description",
|
|
"A minor GC (aka nursery collection) to clear out the buffer used "
|
|
"for recent allocations and move surviving data to the tenured "
|
|
"(long-lived) heap.");
|
|
// No display instructions here, there is special handling in the
|
|
// front-end.
|
|
return schema;
|
|
}
|
|
};
|
|
|
|
profiler_add_marker(
|
|
"GCMinor", baseprofiler::category::GCCC,
|
|
MarkerTiming::Interval(self->mLatestNurseryCollectionStart, now),
|
|
GCMinorMarker{},
|
|
ProfilerString8View::WrapNullTerminatedString(
|
|
JS::MinorGcToJSON(aContext).get()));
|
|
}
|
|
}
|
|
|
|
/* static */
|
|
void CycleCollectedJSRuntime::OutOfMemoryCallback(JSContext* aContext,
|
|
void* aData) {
|
|
CycleCollectedJSRuntime* self = static_cast<CycleCollectedJSRuntime*>(aData);
|
|
|
|
MOZ_ASSERT(CycleCollectedJSContext::Get()->Context() == aContext);
|
|
MOZ_ASSERT(CycleCollectedJSContext::Get()->Runtime() == self);
|
|
|
|
self->OnOutOfMemory();
|
|
}
|
|
|
|
/* static */
|
|
void* CycleCollectedJSRuntime::BeforeWaitCallback(uint8_t* aMemory) {
|
|
MOZ_ASSERT(aMemory);
|
|
|
|
// aMemory is stack allocated memory to contain our RAII object. This allows
|
|
// for us to avoid allocations on the heap during this callback.
|
|
return new (aMemory) dom::AutoYieldJSThreadExecution;
|
|
}
|
|
|
|
/* static */
|
|
void CycleCollectedJSRuntime::AfterWaitCallback(void* aCookie) {
|
|
MOZ_ASSERT(aCookie);
|
|
static_cast<dom::AutoYieldJSThreadExecution*>(aCookie)
|
|
->~AutoYieldJSThreadExecution();
|
|
}
|
|
|
|
struct JsGcTracer : public TraceCallbacks {
|
|
virtual void Trace(JS::Heap<JS::Value>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JS::TraceEdge(static_cast<JSTracer*>(aClosure), aPtr, aName);
|
|
}
|
|
virtual void Trace(JS::Heap<jsid>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JS::TraceEdge(static_cast<JSTracer*>(aClosure), aPtr, aName);
|
|
}
|
|
virtual void Trace(JS::Heap<JSObject*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JS::TraceEdge(static_cast<JSTracer*>(aClosure), aPtr, aName);
|
|
}
|
|
virtual void Trace(nsWrapperCache* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
aPtr->TraceWrapper(static_cast<JSTracer*>(aClosure), aName);
|
|
}
|
|
virtual void Trace(JS::TenuredHeap<JSObject*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JS::TraceEdge(static_cast<JSTracer*>(aClosure), aPtr, aName);
|
|
}
|
|
virtual void Trace(JS::Heap<JSString*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JS::TraceEdge(static_cast<JSTracer*>(aClosure), aPtr, aName);
|
|
}
|
|
virtual void Trace(JS::Heap<JSScript*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JS::TraceEdge(static_cast<JSTracer*>(aClosure), aPtr, aName);
|
|
}
|
|
virtual void Trace(JS::Heap<JSFunction*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JS::TraceEdge(static_cast<JSTracer*>(aClosure), aPtr, aName);
|
|
}
|
|
};
|
|
|
|
void mozilla::TraceScriptHolder(nsISupports* aHolder, JSTracer* aTracer) {
|
|
nsXPCOMCycleCollectionParticipant* participant = nullptr;
|
|
CallQueryInterface(aHolder, &participant);
|
|
participant->Trace(aHolder, JsGcTracer(), aTracer);
|
|
}
|
|
|
|
#if defined(NIGHTLY_BUILD) || defined(MOZ_DEV_EDITION) || defined(DEBUG)
|
|
# define CHECK_SINGLE_ZONE_JS_HOLDERS
|
|
#endif
|
|
|
|
#ifdef CHECK_SINGLE_ZONE_JS_HOLDERS
|
|
|
|
// A tracer that checks that a JS holder only holds JS GC things in a single
|
|
// JS::Zone.
|
|
struct CheckZoneTracer : public TraceCallbacks {
|
|
const char* mClassName;
|
|
mutable JS::Zone* mZone;
|
|
|
|
explicit CheckZoneTracer(const char* aClassName, JS::Zone* aZone = nullptr)
|
|
: mClassName(aClassName), mZone(aZone) {}
|
|
|
|
void checkZone(JS::Zone* aZone, const char* aName) const {
|
|
if (JS::IsAtomsZone(aZone)) {
|
|
// Any holder may contain pointers into the atoms zone.
|
|
return;
|
|
}
|
|
|
|
if (!mZone) {
|
|
mZone = aZone;
|
|
return;
|
|
}
|
|
|
|
if (aZone == mZone) {
|
|
return;
|
|
}
|
|
|
|
// Most JS holders only contain pointers to GC things in a single zone. We
|
|
// group holders by referent zone where possible, allowing us to improve GC
|
|
// performance by only tracing holders for zones that are being collected.
|
|
//
|
|
// Additionally, pointers from any holder into the atoms zone are allowed
|
|
// since all holders are traced when we collect the atoms zone.
|
|
//
|
|
// If you added a holder that has pointers into multiple zones do not
|
|
// use NS_IMPL_CYCLE_COLLECTION_SINGLE_ZONE_SCRIPT_HOLDER_CLASS.
|
|
MOZ_CRASH_UNSAFE_PRINTF(
|
|
"JS holder %s contains pointers to GC things in more than one zone ("
|
|
"found in %s)\n",
|
|
mClassName, aName);
|
|
}
|
|
|
|
virtual void Trace(JS::Heap<JS::Value>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JS::Value value = aPtr->unbarrieredGet();
|
|
if (value.isGCThing()) {
|
|
checkZone(JS::GetGCThingZone(value.toGCCellPtr()), aName);
|
|
}
|
|
}
|
|
virtual void Trace(JS::Heap<jsid>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
jsid id = aPtr->unbarrieredGet();
|
|
if (id.isGCThing()) {
|
|
MOZ_ASSERT(JS::IsAtomsZone(JS::GetTenuredGCThingZone(id.toGCCellPtr())));
|
|
}
|
|
}
|
|
virtual void Trace(JS::Heap<JSObject*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JSObject* obj = aPtr->unbarrieredGet();
|
|
if (obj) {
|
|
checkZone(js::GetObjectZoneFromAnyThread(obj), aName);
|
|
}
|
|
}
|
|
virtual void Trace(nsWrapperCache* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JSObject* obj = aPtr->GetWrapperPreserveColor();
|
|
if (obj) {
|
|
checkZone(js::GetObjectZoneFromAnyThread(obj), aName);
|
|
}
|
|
}
|
|
virtual void Trace(JS::TenuredHeap<JSObject*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JSObject* obj = aPtr->unbarrieredGetPtr();
|
|
if (obj) {
|
|
checkZone(js::GetObjectZoneFromAnyThread(obj), aName);
|
|
}
|
|
}
|
|
virtual void Trace(JS::Heap<JSString*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JSString* str = aPtr->unbarrieredGet();
|
|
if (str) {
|
|
checkZone(JS::GetStringZone(str), aName);
|
|
}
|
|
}
|
|
virtual void Trace(JS::Heap<JSScript*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JSScript* script = aPtr->unbarrieredGet();
|
|
if (script) {
|
|
checkZone(JS::GetTenuredGCThingZone(JS::GCCellPtr(script)), aName);
|
|
}
|
|
}
|
|
virtual void Trace(JS::Heap<JSFunction*>* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
JSFunction* fun = aPtr->unbarrieredGet();
|
|
if (fun) {
|
|
checkZone(js::GetObjectZoneFromAnyThread(JS_GetFunctionObject(fun)),
|
|
aName);
|
|
}
|
|
}
|
|
};
|
|
|
|
static inline void CheckHolderIsSingleZone(
|
|
void* aHolder, nsCycleCollectionParticipant* aParticipant,
|
|
JS::Zone* aZone) {
|
|
CheckZoneTracer tracer(aParticipant->ClassName(), aZone);
|
|
aParticipant->Trace(aHolder, tracer, nullptr);
|
|
}
|
|
|
|
#endif
|
|
|
|
static inline bool ShouldCheckSingleZoneHolders() {
|
|
#if defined(DEBUG)
|
|
return true;
|
|
#elif defined(NIGHTLY_BUILD) || defined(MOZ_DEV_EDITION)
|
|
// Don't check every time to avoid performance impact.
|
|
return rand() % 256 == 0;
|
|
#else
|
|
return false;
|
|
#endif
|
|
}
|
|
|
|
#ifdef NS_BUILD_REFCNT_LOGGING
|
|
void CycleCollectedJSRuntime::TraceAllNativeGrayRoots(JSTracer* aTracer) {
|
|
MOZ_RELEASE_ASSERT(mHolderIter.isNothing());
|
|
js::SliceBudget budget = js::SliceBudget::unlimited();
|
|
MOZ_ALWAYS_TRUE(
|
|
TraceNativeGrayRoots(aTracer, JSHolderMap::AllHolders, budget));
|
|
}
|
|
#endif
|
|
|
|
bool CycleCollectedJSRuntime::TraceNativeGrayRoots(
|
|
JSTracer* aTracer, JSHolderMap::WhichHolders aWhich,
|
|
js::SliceBudget& aBudget) {
|
|
if (!mHolderIter) {
|
|
// NB: This is here just to preserve the existing XPConnect order. I doubt
|
|
// it would hurt to do this after the JS holders.
|
|
TraceAdditionalNativeGrayRoots(aTracer);
|
|
|
|
mHolderIter.emplace(mJSHolders, aWhich);
|
|
aBudget.forceCheck();
|
|
} else {
|
|
// Holders may have been removed between slices, so we may need to update
|
|
// the iterator.
|
|
mHolderIter->UpdateForRemovals();
|
|
}
|
|
|
|
bool finished = TraceJSHolders(aTracer, *mHolderIter, aBudget);
|
|
if (finished) {
|
|
mHolderIter.reset();
|
|
}
|
|
|
|
return finished;
|
|
}
|
|
|
|
bool CycleCollectedJSRuntime::TraceJSHolders(JSTracer* aTracer,
|
|
JSHolderMap::Iter& aIter,
|
|
js::SliceBudget& aBudget) {
|
|
bool checkSingleZoneHolders = ShouldCheckSingleZoneHolders();
|
|
|
|
while (!aIter.Done() && !aBudget.isOverBudget()) {
|
|
void* holder = aIter->mHolder;
|
|
nsScriptObjectTracer* tracer = aIter->mTracer;
|
|
|
|
#ifdef CHECK_SINGLE_ZONE_JS_HOLDERS
|
|
if (checkSingleZoneHolders && tracer->IsSingleZoneJSHolder()) {
|
|
CheckHolderIsSingleZone(holder, tracer, aIter.Zone());
|
|
}
|
|
#else
|
|
Unused << checkSingleZoneHolders;
|
|
#endif
|
|
|
|
tracer->Trace(holder, JsGcTracer(), aTracer);
|
|
|
|
aIter.Next();
|
|
aBudget.step();
|
|
}
|
|
|
|
return aIter.Done();
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::AddJSHolder(void* aHolder,
|
|
nsScriptObjectTracer* aTracer,
|
|
JS::Zone* aZone) {
|
|
mJSHolders.Put(aHolder, aTracer, aZone);
|
|
}
|
|
|
|
struct ClearJSHolder : public TraceCallbacks {
|
|
virtual void Trace(JS::Heap<JS::Value>* aPtr, const char*,
|
|
void*) const override {
|
|
aPtr->setUndefined();
|
|
}
|
|
|
|
virtual void Trace(JS::Heap<jsid>* aPtr, const char*, void*) const override {
|
|
*aPtr = JS::PropertyKey::Void();
|
|
}
|
|
|
|
virtual void Trace(JS::Heap<JSObject*>* aPtr, const char*,
|
|
void*) const override {
|
|
*aPtr = nullptr;
|
|
}
|
|
|
|
virtual void Trace(nsWrapperCache* aPtr, const char* aName,
|
|
void* aClosure) const override {
|
|
aPtr->ClearWrapper();
|
|
}
|
|
|
|
virtual void Trace(JS::TenuredHeap<JSObject*>* aPtr, const char*,
|
|
void*) const override {
|
|
*aPtr = nullptr;
|
|
}
|
|
|
|
virtual void Trace(JS::Heap<JSString*>* aPtr, const char*,
|
|
void*) const override {
|
|
*aPtr = nullptr;
|
|
}
|
|
|
|
virtual void Trace(JS::Heap<JSScript*>* aPtr, const char*,
|
|
void*) const override {
|
|
*aPtr = nullptr;
|
|
}
|
|
|
|
virtual void Trace(JS::Heap<JSFunction*>* aPtr, const char*,
|
|
void*) const override {
|
|
*aPtr = nullptr;
|
|
}
|
|
};
|
|
|
|
void CycleCollectedJSRuntime::RemoveJSHolder(void* aHolder) {
|
|
nsScriptObjectTracer* tracer = mJSHolders.Extract(aHolder);
|
|
if (tracer) {
|
|
// Bug 1531951: The analysis can't see through the virtual call but we know
|
|
// that the ClearJSHolder tracer will never GC.
|
|
JS::AutoSuppressGCAnalysis nogc;
|
|
tracer->Trace(aHolder, ClearJSHolder(), nullptr);
|
|
}
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
static void AssertNoGcThing(JS::GCCellPtr aGCThing, const char* aName,
|
|
void* aClosure) {
|
|
MOZ_ASSERT(!aGCThing);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::AssertNoObjectsToTrace(void* aPossibleJSHolder) {
|
|
nsScriptObjectTracer* tracer = mJSHolders.Get(aPossibleJSHolder);
|
|
if (tracer) {
|
|
tracer->Trace(aPossibleJSHolder, TraceCallbackFunc(AssertNoGcThing),
|
|
nullptr);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
nsCycleCollectionParticipant* CycleCollectedJSRuntime::GCThingParticipant() {
|
|
return &mGCThingCycleCollectorGlobal;
|
|
}
|
|
|
|
nsCycleCollectionParticipant* CycleCollectedJSRuntime::ZoneParticipant() {
|
|
return &mJSZoneCycleCollectorGlobal;
|
|
}
|
|
|
|
nsresult CycleCollectedJSRuntime::TraverseRoots(
|
|
nsCycleCollectionNoteRootCallback& aCb) {
|
|
TraverseNativeRoots(aCb);
|
|
|
|
NoteWeakMapsTracer trc(mJSRuntime, aCb);
|
|
js::TraceWeakMaps(&trc);
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
bool CycleCollectedJSRuntime::UsefulToMergeZones() const { return false; }
|
|
|
|
void CycleCollectedJSRuntime::FixWeakMappingGrayBits() const {
|
|
MOZ_ASSERT(!JS::IsIncrementalGCInProgress(mJSRuntime),
|
|
"Don't call FixWeakMappingGrayBits during a GC.");
|
|
FixWeakMappingGrayBitsTracer fixer(mJSRuntime);
|
|
fixer.FixAll();
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::CheckGrayBits() const {
|
|
MOZ_ASSERT(!JS::IsIncrementalGCInProgress(mJSRuntime),
|
|
"Don't call CheckGrayBits during a GC.");
|
|
|
|
#ifndef ANDROID
|
|
// Bug 1346874 - The gray state check is expensive. Android tests are already
|
|
// slow enough that this check can easily push them over the threshold to a
|
|
// timeout.
|
|
|
|
MOZ_ASSERT(js::CheckGrayMarkingState(mJSRuntime));
|
|
MOZ_ASSERT(CheckWeakMappingGrayBitsTracer::Check(mJSRuntime));
|
|
#endif
|
|
}
|
|
|
|
bool CycleCollectedJSRuntime::AreGCGrayBitsValid() const {
|
|
return js::AreGCGrayBitsValid(mJSRuntime);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::GarbageCollect(JS::GCOptions aOptions,
|
|
JS::GCReason aReason) const {
|
|
JSContext* cx = CycleCollectedJSContext::Get()->Context();
|
|
JS::PrepareForFullGC(cx);
|
|
JS::NonIncrementalGC(cx, aOptions, aReason);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::JSObjectsTenured() {
|
|
JSContext* cx = CycleCollectedJSContext::Get()->Context();
|
|
for (auto iter = mNurseryObjects.Iter(); !iter.Done(); iter.Next()) {
|
|
nsWrapperCache* cache = iter.Get();
|
|
JSObject* wrapper = cache->GetWrapperMaybeDead();
|
|
MOZ_DIAGNOSTIC_ASSERT(wrapper);
|
|
if (!JS::ObjectIsTenured(wrapper)) {
|
|
MOZ_ASSERT(!cache->PreservingWrapper());
|
|
js::gc::FinalizeDeadNurseryObject(cx, wrapper);
|
|
}
|
|
}
|
|
|
|
mNurseryObjects.Clear();
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::NurseryWrapperAdded(nsWrapperCache* aCache) {
|
|
MOZ_ASSERT(aCache);
|
|
MOZ_ASSERT(aCache->GetWrapperMaybeDead());
|
|
MOZ_ASSERT(!JS::ObjectIsTenured(aCache->GetWrapperMaybeDead()));
|
|
mNurseryObjects.InfallibleAppend(aCache);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::DeferredFinalize(
|
|
DeferredFinalizeAppendFunction aAppendFunc, DeferredFinalizeFunction aFunc,
|
|
void* aThing) {
|
|
// Tell the analysis that the function pointers will not GC.
|
|
JS::AutoSuppressGCAnalysis suppress;
|
|
mDeferredFinalizerTable.WithEntryHandle(aFunc, [&](auto&& entry) {
|
|
if (entry) {
|
|
aAppendFunc(entry.Data(), aThing);
|
|
} else {
|
|
entry.Insert(aAppendFunc(nullptr, aThing));
|
|
}
|
|
});
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::DeferredFinalize(nsISupports* aSupports) {
|
|
typedef DeferredFinalizerImpl<nsISupports> Impl;
|
|
DeferredFinalize(Impl::AppendDeferredFinalizePointer, Impl::DeferredFinalize,
|
|
aSupports);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::DumpJSHeap(FILE* aFile) {
|
|
JSContext* cx = CycleCollectedJSContext::Get()->Context();
|
|
|
|
mozilla::MallocSizeOf mallocSizeOf =
|
|
PR_GetEnv("MOZ_GC_LOG_SIZE") ? moz_malloc_size_of : nullptr;
|
|
js::DumpHeap(cx, aFile, js::CollectNurseryBeforeDump, mallocSizeOf);
|
|
}
|
|
|
|
IncrementalFinalizeRunnable::IncrementalFinalizeRunnable(
|
|
CycleCollectedJSRuntime* aRt, DeferredFinalizerTable& aFinalizers)
|
|
: DiscardableRunnable("IncrementalFinalizeRunnable"),
|
|
mRuntime(aRt),
|
|
mFinalizeFunctionToRun(0),
|
|
mReleasing(false) {
|
|
for (auto iter = aFinalizers.Iter(); !iter.Done(); iter.Next()) {
|
|
DeferredFinalizeFunction& function = iter.Key();
|
|
void*& data = iter.Data();
|
|
|
|
DeferredFinalizeFunctionHolder* holder =
|
|
mDeferredFinalizeFunctions.AppendElement();
|
|
holder->run = function;
|
|
holder->data = data;
|
|
|
|
iter.Remove();
|
|
}
|
|
MOZ_ASSERT(mDeferredFinalizeFunctions.Length());
|
|
}
|
|
|
|
IncrementalFinalizeRunnable::~IncrementalFinalizeRunnable() {
|
|
MOZ_ASSERT(!mDeferredFinalizeFunctions.Length());
|
|
MOZ_ASSERT(!mRuntime);
|
|
}
|
|
|
|
void IncrementalFinalizeRunnable::ReleaseNow(bool aLimited) {
|
|
if (mReleasing) {
|
|
NS_WARNING("Re-entering ReleaseNow");
|
|
return;
|
|
}
|
|
{
|
|
AUTO_PROFILER_LABEL("IncrementalFinalizeRunnable::ReleaseNow",
|
|
GCCC_Finalize);
|
|
|
|
mozilla::AutoRestore<bool> ar(mReleasing);
|
|
mReleasing = true;
|
|
MOZ_ASSERT(mDeferredFinalizeFunctions.Length() != 0,
|
|
"We should have at least ReleaseSliceNow to run");
|
|
MOZ_ASSERT(mFinalizeFunctionToRun < mDeferredFinalizeFunctions.Length(),
|
|
"No more finalizers to run?");
|
|
|
|
TimeDuration sliceTime = TimeDuration::FromMilliseconds(SliceMillis);
|
|
TimeStamp started = aLimited ? TimeStamp::Now() : TimeStamp();
|
|
bool timeout = false;
|
|
do {
|
|
const DeferredFinalizeFunctionHolder& function =
|
|
mDeferredFinalizeFunctions[mFinalizeFunctionToRun];
|
|
if (aLimited) {
|
|
bool done = false;
|
|
while (!timeout && !done) {
|
|
/*
|
|
* We don't want to read the clock too often, so we try to
|
|
* release slices of 100 items.
|
|
*/
|
|
done = function.run(100, function.data);
|
|
timeout = TimeStamp::Now() - started >= sliceTime;
|
|
}
|
|
if (done) {
|
|
++mFinalizeFunctionToRun;
|
|
}
|
|
if (timeout) {
|
|
break;
|
|
}
|
|
} else {
|
|
while (!function.run(UINT32_MAX, function.data))
|
|
;
|
|
++mFinalizeFunctionToRun;
|
|
}
|
|
} while (mFinalizeFunctionToRun < mDeferredFinalizeFunctions.Length());
|
|
}
|
|
|
|
if (mFinalizeFunctionToRun == mDeferredFinalizeFunctions.Length()) {
|
|
MOZ_ASSERT(mRuntime->mFinalizeRunnable == this);
|
|
mDeferredFinalizeFunctions.Clear();
|
|
CycleCollectedJSRuntime* runtime = mRuntime;
|
|
mRuntime = nullptr;
|
|
// NB: This may delete this!
|
|
runtime->mFinalizeRunnable = nullptr;
|
|
}
|
|
}
|
|
|
|
NS_IMETHODIMP
|
|
IncrementalFinalizeRunnable::Run() {
|
|
if (!mDeferredFinalizeFunctions.Length()) {
|
|
/* These items were already processed synchronously in JSGC_END. */
|
|
MOZ_ASSERT(!mRuntime);
|
|
return NS_OK;
|
|
}
|
|
|
|
MOZ_ASSERT(mRuntime->mFinalizeRunnable == this);
|
|
TimeStamp start = TimeStamp::Now();
|
|
ReleaseNow(true);
|
|
|
|
if (mDeferredFinalizeFunctions.Length()) {
|
|
nsresult rv = NS_DispatchToCurrentThread(this);
|
|
if (NS_FAILED(rv)) {
|
|
ReleaseNow(false);
|
|
}
|
|
} else {
|
|
MOZ_ASSERT(!mRuntime);
|
|
}
|
|
|
|
uint32_t duration = (uint32_t)((TimeStamp::Now() - start).ToMilliseconds());
|
|
Telemetry::Accumulate(Telemetry::DEFERRED_FINALIZE_ASYNC, duration);
|
|
|
|
return NS_OK;
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::FinalizeDeferredThings(
|
|
DeferredFinalizeType aType) {
|
|
// If mFinalizeRunnable isn't null, we didn't finalize everything from the
|
|
// previous GC.
|
|
if (mFinalizeRunnable) {
|
|
if (aType == FinalizeLater) {
|
|
// We need to defer all finalization until we return to the event loop,
|
|
// so leave things alone. Any new objects to be finalized from the current
|
|
// GC will be handled by the existing mFinalizeRunnable.
|
|
return;
|
|
}
|
|
MOZ_ASSERT(aType == FinalizeIncrementally || aType == FinalizeNow);
|
|
// If we're finalizing incrementally, we don't want finalizers to build up,
|
|
// so try to finish them off now.
|
|
// If we're finalizing synchronously, also go ahead and clear them out,
|
|
// so we make sure as much as possible is freed.
|
|
mFinalizeRunnable->ReleaseNow(false);
|
|
if (mFinalizeRunnable) {
|
|
// If we re-entered ReleaseNow, we couldn't delete mFinalizeRunnable and
|
|
// we need to just continue processing it.
|
|
return;
|
|
}
|
|
}
|
|
|
|
// If there's nothing to finalize, don't create a new runnable.
|
|
if (mDeferredFinalizerTable.Count() == 0) {
|
|
return;
|
|
}
|
|
|
|
mFinalizeRunnable =
|
|
new IncrementalFinalizeRunnable(this, mDeferredFinalizerTable);
|
|
|
|
// Everything should be gone now.
|
|
MOZ_ASSERT(mDeferredFinalizerTable.Count() == 0);
|
|
|
|
if (aType == FinalizeNow) {
|
|
mFinalizeRunnable->ReleaseNow(false);
|
|
MOZ_ASSERT(!mFinalizeRunnable);
|
|
} else {
|
|
MOZ_ASSERT(aType == FinalizeIncrementally || aType == FinalizeLater);
|
|
NS_DispatchToCurrentThreadQueue(do_AddRef(mFinalizeRunnable), 2500,
|
|
EventQueuePriority::Idle);
|
|
}
|
|
}
|
|
|
|
const char* CycleCollectedJSRuntime::OOMStateToString(
|
|
const OOMState aOomState) const {
|
|
switch (aOomState) {
|
|
case OOMState::OK:
|
|
return "OK";
|
|
case OOMState::Reporting:
|
|
return "Reporting";
|
|
case OOMState::Reported:
|
|
return "Reported";
|
|
case OOMState::Recovered:
|
|
return "Recovered";
|
|
default:
|
|
MOZ_ASSERT_UNREACHABLE("OOMState holds an invalid value");
|
|
return "Unknown";
|
|
}
|
|
}
|
|
|
|
bool CycleCollectedJSRuntime::OOMReported() {
|
|
return mOutOfMemoryState == OOMState::Reported;
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::AnnotateAndSetOutOfMemory(OOMState* aStatePtr,
|
|
OOMState aNewState) {
|
|
*aStatePtr = aNewState;
|
|
CrashReporter::Annotation annotation =
|
|
(aStatePtr == &mOutOfMemoryState)
|
|
? CrashReporter::Annotation::JSOutOfMemory
|
|
: CrashReporter::Annotation::JSLargeAllocationFailure;
|
|
|
|
CrashReporter::AnnotateCrashReport(
|
|
annotation, nsDependentCString(OOMStateToString(aNewState)));
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::OnGC(JSContext* aContext, JSGCStatus aStatus,
|
|
JS::GCReason aReason) {
|
|
switch (aStatus) {
|
|
case JSGC_BEGIN:
|
|
MOZ_RELEASE_ASSERT(mHolderIter.isNothing());
|
|
nsCycleCollector_prepareForGarbageCollection();
|
|
PrepareWaitingZonesForGC();
|
|
break;
|
|
case JSGC_END: {
|
|
MOZ_RELEASE_ASSERT(mHolderIter.isNothing());
|
|
if (mOutOfMemoryState == OOMState::Reported) {
|
|
AnnotateAndSetOutOfMemory(&mOutOfMemoryState, OOMState::Recovered);
|
|
}
|
|
if (mLargeAllocationFailureState == OOMState::Reported) {
|
|
AnnotateAndSetOutOfMemory(&mLargeAllocationFailureState,
|
|
OOMState::Recovered);
|
|
}
|
|
|
|
DeferredFinalizeType finalizeType;
|
|
if (JS_IsExceptionPending(aContext)) {
|
|
// There is a pending exception. The finalizers are not set up to run
|
|
// in that state, so don't run the finalizer until we've returned to the
|
|
// event loop.
|
|
finalizeType = FinalizeLater;
|
|
} else if (JS::InternalGCReason(aReason)) {
|
|
if (aReason == JS::GCReason::DESTROY_RUNTIME) {
|
|
// We're shutting down, so we need to destroy things immediately.
|
|
finalizeType = FinalizeNow;
|
|
} else {
|
|
// We may be in the middle of running some code that the JIT has
|
|
// assumed can't have certain kinds of side effects. Finalizers can do
|
|
// all sorts of things, such as run JS, so we want to run them later,
|
|
// after we've returned to the event loop.
|
|
finalizeType = FinalizeLater;
|
|
}
|
|
} else if (JS::WasIncrementalGC(mJSRuntime)) {
|
|
// The GC was incremental, so we probably care about pauses. Try to
|
|
// break up finalization, but it is okay if we do some now.
|
|
finalizeType = FinalizeIncrementally;
|
|
} else {
|
|
// If we're running a synchronous GC, we probably want to free things as
|
|
// quickly as possible. This can happen during testing or if memory is
|
|
// low.
|
|
finalizeType = FinalizeNow;
|
|
}
|
|
FinalizeDeferredThings(finalizeType);
|
|
|
|
break;
|
|
}
|
|
default:
|
|
MOZ_CRASH();
|
|
}
|
|
|
|
CustomGCCallback(aStatus);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::OnOutOfMemory() {
|
|
AnnotateAndSetOutOfMemory(&mOutOfMemoryState, OOMState::Reporting);
|
|
CustomOutOfMemoryCallback();
|
|
AnnotateAndSetOutOfMemory(&mOutOfMemoryState, OOMState::Reported);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::SetLargeAllocationFailure(OOMState aNewState) {
|
|
AnnotateAndSetOutOfMemory(&mLargeAllocationFailureState, aNewState);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::PrepareWaitingZonesForGC() {
|
|
JSContext* cx = CycleCollectedJSContext::Get()->Context();
|
|
if (mZonesWaitingForGC.Count() == 0) {
|
|
JS::PrepareForFullGC(cx);
|
|
} else {
|
|
for (const auto& key : mZonesWaitingForGC) {
|
|
JS::PrepareZoneForGC(cx, key);
|
|
}
|
|
mZonesWaitingForGC.Clear();
|
|
}
|
|
}
|
|
|
|
/* static */
|
|
void CycleCollectedJSRuntime::OnZoneDestroyed(JS::GCContext* aGcx,
|
|
JS::Zone* aZone) {
|
|
// Remove the zone from the set of zones waiting for GC, if present. This can
|
|
// happen if a zone is added to the set during an incremental GC in which it
|
|
// is later destroyed.
|
|
CycleCollectedJSRuntime* runtime = Get();
|
|
runtime->mZonesWaitingForGC.Remove(aZone);
|
|
}
|
|
|
|
void CycleCollectedJSRuntime::EnvironmentPreparer::invoke(
|
|
JS::HandleObject global, js::ScriptEnvironmentPreparer::Closure& closure) {
|
|
MOZ_ASSERT(JS_IsGlobalObject(global));
|
|
nsIGlobalObject* nativeGlobal = xpc::NativeGlobal(global);
|
|
|
|
// Not much we can do if we simply don't have a usable global here...
|
|
NS_ENSURE_TRUE_VOID(nativeGlobal && nativeGlobal->HasJSGlobal());
|
|
|
|
AutoEntryScript aes(nativeGlobal, "JS-engine-initiated execution");
|
|
|
|
MOZ_ASSERT(!JS_IsExceptionPending(aes.cx()));
|
|
|
|
DebugOnly<bool> ok = closure(aes.cx());
|
|
|
|
MOZ_ASSERT_IF(ok, !JS_IsExceptionPending(aes.cx()));
|
|
|
|
// The AutoEntryScript will check for JS_IsExceptionPending on the
|
|
// JSContext and report it as needed as it comes off the stack.
|
|
}
|
|
|
|
/* static */
|
|
CycleCollectedJSRuntime* CycleCollectedJSRuntime::Get() {
|
|
auto context = CycleCollectedJSContext::Get();
|
|
if (context) {
|
|
return context->Runtime();
|
|
}
|
|
return nullptr;
|
|
}
|
|
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#ifdef MOZ_JS_DEV_ERROR_INTERCEPTOR
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namespace js {
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extern void DumpValue(const JS::Value& val);
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}
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void CycleCollectedJSRuntime::ErrorInterceptor::Shutdown(JSRuntime* rt) {
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JS_SetErrorInterceptorCallback(rt, nullptr);
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mThrownError.reset();
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}
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/* virtual */
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void CycleCollectedJSRuntime::ErrorInterceptor::interceptError(
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JSContext* cx, JS::HandleValue exn) {
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if (mThrownError) {
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// We already have an error, we don't need anything more.
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return;
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}
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if (!nsContentUtils::ThreadsafeIsSystemCaller(cx)) {
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// We are only interested in chrome code.
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return;
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}
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const auto type = JS_GetErrorType(exn);
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if (!type) {
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// This is not one of the primitive error types.
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return;
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}
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switch (*type) {
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case JSExnType::JSEXN_REFERENCEERR:
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case JSExnType::JSEXN_SYNTAXERR:
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break;
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default:
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// Not one of the errors we are interested in.
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// Note that we are not interested in instances of `TypeError`
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// for the time being, as DOM (ab)uses this constructor to represent
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// all sorts of errors that are not even remotely related to type
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// errors (e.g. some network errors).
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// If we ever have a mechanism to differentiate between DOM-thrown
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// and SpiderMonkey-thrown instances of `TypeError`, we should
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// consider watching for `TypeError` here.
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return;
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}
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// Now copy the details of the exception locally.
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// While copying the details of an exception could be expensive, in most runs,
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// this will be done at most once during the execution of the process, so the
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// total cost should be reasonable.
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ErrorDetails details;
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details.mType = *type;
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// If `exn` isn't an exception object, `ExtractErrorValues` could end up
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// calling `toString()`, which could in turn end up throwing an error. While
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// this should work, we want to avoid that complex use case. Fortunately, we
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// have already checked above that `exn` is an exception object, so nothing
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// such should happen.
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nsContentUtils::ExtractErrorValues(cx, exn, details.mFilename, &details.mLine,
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&details.mColumn, details.mMessage);
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JS::UniqueChars buf =
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JS::FormatStackDump(cx, /* showArgs = */ false, /* showLocals = */ false,
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/* showThisProps = */ false);
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CopyUTF8toUTF16(mozilla::MakeStringSpan(buf.get()), details.mStack);
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mThrownError.emplace(std::move(details));
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}
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void CycleCollectedJSRuntime::ClearRecentDevError() {
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mErrorInterceptor.mThrownError.reset();
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}
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bool CycleCollectedJSRuntime::GetRecentDevError(
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JSContext* cx, JS::MutableHandle<JS::Value> error) {
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if (!mErrorInterceptor.mThrownError) {
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return true;
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}
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// Create a copy of the exception.
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JS::RootedObject obj(cx, JS_NewPlainObject(cx));
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if (!obj) {
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return false;
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}
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JS::RootedValue message(cx);
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JS::RootedValue filename(cx);
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JS::RootedValue stack(cx);
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if (!ToJSValue(cx, mErrorInterceptor.mThrownError->mMessage, &message) ||
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!ToJSValue(cx, mErrorInterceptor.mThrownError->mFilename, &filename) ||
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!ToJSValue(cx, mErrorInterceptor.mThrownError->mStack, &stack)) {
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return false;
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}
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// Build the object.
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const auto FLAGS = JSPROP_READONLY | JSPROP_ENUMERATE | JSPROP_PERMANENT;
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if (!JS_DefineProperty(cx, obj, "message", message, FLAGS) ||
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!JS_DefineProperty(cx, obj, "fileName", filename, FLAGS) ||
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!JS_DefineProperty(cx, obj, "lineNumber",
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mErrorInterceptor.mThrownError->mLine, FLAGS) ||
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!JS_DefineProperty(cx, obj, "stack", stack, FLAGS)) {
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return false;
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}
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// Pass the result.
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error.setObject(*obj);
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return true;
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}
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#endif // MOZ_JS_DEV_ERROR_INTERCEPTOR
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#undef MOZ_JS_DEV_ERROR_INTERCEPTOR
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