diff options
Diffstat (limited to 'dom/base/nsJSEnvironment.cpp')
| -rw-r--r-- | dom/base/nsJSEnvironment.cpp | 2448 |
1 files changed, 2448 insertions, 0 deletions
diff --git a/dom/base/nsJSEnvironment.cpp b/dom/base/nsJSEnvironment.cpp new file mode 100644 index 0000000000..1d2eb16885 --- /dev/null +++ b/dom/base/nsJSEnvironment.cpp @@ -0,0 +1,2448 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "nsError.h" +#include "nsJSEnvironment.h" +#include "nsIScriptGlobalObject.h" +#include "nsIScriptObjectPrincipal.h" +#include "nsPIDOMWindow.h" +#include "nsDOMCID.h" +#include "nsIXPConnect.h" +#include "nsCOMPtr.h" +#include "nsISupportsPrimitives.h" +#include "nsReadableUtils.h" +#include "nsDOMJSUtils.h" +#include "nsJSUtils.h" +#include "nsIDocShell.h" +#include "nsIDocShellTreeItem.h" +#include "nsPresContext.h" +#include "nsIConsoleService.h" +#include "nsIInterfaceRequestor.h" +#include "nsIInterfaceRequestorUtils.h" +#include "nsIObserverService.h" +#include "nsITimer.h" +#include "nsAtom.h" +#include "nsContentUtils.h" +#include "mozilla/EventDispatcher.h" +#include "mozilla/HoldDropJSObjects.h" +#include "nsIContent.h" +#include "nsCycleCollector.h" +#include "nsXPCOMCIDInternal.h" +#include "nsServiceManagerUtils.h" +#include "nsTextFormatter.h" +#ifdef XP_WIN +# include <process.h> +# define getpid _getpid +#else +# include <unistd.h> // for getpid() +#endif +#include "xpcpublic.h" + +#include "jsapi.h" +#include "js/Array.h" // JS::NewArrayObject +#include "js/PropertyAndElement.h" // JS_DefineProperty +#include "js/PropertySpec.h" +#include "js/SliceBudget.h" +#include "js/Wrapper.h" +#include "nsIArray.h" +#include "CCGCScheduler.h" +#include "WrapperFactory.h" +#include "nsGlobalWindowInner.h" +#include "nsGlobalWindowOuter.h" +#include "mozilla/AutoRestore.h" +#include "mozilla/BasePrincipal.h" +#include "mozilla/PresShell.h" +#include "mozilla/SchedulerGroup.h" +#include "mozilla/StaticPrefs_dom.h" +#include "mozilla/StaticPrefs_javascript.h" +#include "mozilla/StaticPtr.h" +#include "mozilla/dom/BrowsingContext.h" +#include "mozilla/dom/DOMException.h" +#include "mozilla/dom/DOMExceptionBinding.h" +#include "mozilla/dom/Element.h" +#include "mozilla/dom/ErrorEvent.h" +#include "mozilla/dom/FetchUtil.h" +#include "mozilla/dom/RootedDictionary.h" +#include "mozilla/dom/ScriptSettings.h" +#include "mozilla/dom/SerializedStackHolder.h" +#include "mozilla/CycleCollectedJSRuntime.h" +#include "nsRefreshDriver.h" +#include "nsJSPrincipals.h" +#include "AccessCheck.h" +#include "mozilla/Logging.h" +#include "prthread.h" + +#include "mozilla/Preferences.h" +#include "mozilla/Telemetry.h" +#include "mozilla/dom/BindingUtils.h" +#include "mozilla/Attributes.h" +#include "mozilla/dom/CanvasRenderingContext2DBinding.h" +#include "mozilla/ContentEvents.h" +#include "mozilla/CycleCollectedJSContext.h" +#include "nsCycleCollectionNoteRootCallback.h" +#include "nsViewManager.h" +#include "mozilla/EventStateManager.h" +#include "mozilla/ProfilerLabels.h" +#include "mozilla/ProfilerMarkers.h" +#if defined(MOZ_MEMORY) +# include "mozmemory.h" +#endif + +using namespace mozilla; +using namespace mozilla::dom; + +// Thank you Microsoft! +#ifdef CompareString +# undef CompareString +#endif + +static JS::GCSliceCallback sPrevGCSliceCallback; + +static bool sIncrementalCC = false; + +static bool sIsInitialized; +static bool sShuttingDown; + +static CCGCScheduler* sScheduler = nullptr; +static std::aligned_storage_t<sizeof(*sScheduler)> sSchedulerStorage; + +struct CycleCollectorStats { + constexpr CycleCollectorStats() = default; + void Init(); + void Clear(); + void PrepareForCycleCollection(TimeStamp aNow); + void AfterPrepareForCycleCollectionSlice(TimeStamp aDeadline, + TimeStamp aBeginTime, + TimeStamp aMaybeAfterGCTime); + void AfterCycleCollectionSlice(); + void AfterSyncForgetSkippable(TimeStamp beginTime); + void AfterForgetSkippable(TimeDuration duration, uint32_t aRemovedPurples); + void AfterCycleCollection(); + + void SendTelemetry(TimeDuration aCCNowDuration, TimeStamp aPrevCCEnd) const; + void MaybeLogStats(const CycleCollectorResults& aResults, + uint32_t aCleanups) const; + void MaybeNotifyStats(const CycleCollectorResults& aResults, + TimeDuration aCCNowDuration, uint32_t aCleanups) const; + + // Time the current slice began, including any GC finishing. + TimeStamp mBeginSliceTime; + + // Time the previous slice of the current CC ended. + TimeStamp mEndSliceTime; + + // Time the current cycle collection began. + TimeStamp mBeginTime; + + // The longest GC finishing duration for any slice of the current CC. + TimeDuration mMaxGCDuration; + + // True if we ran sync forget skippable in any slice of the current CC. + bool mRanSyncForgetSkippable = false; + + // Number of suspected objects at the start of the current CC. + uint32_t mSuspected = 0; + + // The longest duration spent on sync forget skippable in any slice of the + // current CC. + TimeDuration mMaxSkippableDuration; + + // The longest pause of any slice in the current CC. + TimeDuration mMaxSliceTime; + + // The longest slice time since ClearMaxCCSliceTime() was called. + TimeDuration mMaxSliceTimeSinceClear; + + // The total amount of time spent actually running the current CC. + TimeDuration mTotalSliceTime; + + // True if we were locked out by the GC in any slice of the current CC. + bool mAnyLockedOut = false; + + // A file to dump CC activity to; set by MOZ_CCTIMER environment variable. + FILE* mFile = nullptr; + + // In case CC slice was triggered during idle time, set to the end of the idle + // period. + TimeStamp mIdleDeadline; + + TimeDuration mMinForgetSkippableTime; + TimeDuration mMaxForgetSkippableTime; + TimeDuration mTotalForgetSkippableTime; + uint32_t mForgetSkippableBeforeCC = 0; + + uint32_t mRemovedPurples = 0; +}; + +static CycleCollectorStats sCCStats; + +static const char* ProcessNameForCollectorLog() { + return XRE_GetProcessType() == GeckoProcessType_Default ? "default" + : "content"; +} + +namespace xpc { + +// This handles JS Exceptions (via ExceptionStackOrNull), DOM and XPC +// Exceptions, and arbitrary values that were associated with a stack by the +// JS engine when they were thrown, as specified by exceptionStack. +// +// Note that the returned stackObj and stackGlobal are _not_ wrapped into the +// compartment of exceptionValue. +void FindExceptionStackForConsoleReport( + nsPIDOMWindowInner* win, JS::Handle<JS::Value> exceptionValue, + JS::Handle<JSObject*> exceptionStack, JS::MutableHandle<JSObject*> stackObj, + JS::MutableHandle<JSObject*> stackGlobal) { + stackObj.set(nullptr); + stackGlobal.set(nullptr); + + if (!exceptionValue.isObject()) { + // Use the stack provided by the JS engine, if available. This will not be + // a wrapper. + if (exceptionStack) { + stackObj.set(exceptionStack); + stackGlobal.set(JS::GetNonCCWObjectGlobal(exceptionStack)); + } + return; + } + + if (win && win->AsGlobal()->IsDying()) { + // Pretend like we have no stack, so we don't end up keeping the global + // alive via the stack. + return; + } + + JS::RootingContext* rcx = RootingCx(); + JS::Rooted<JSObject*> exceptionObject(rcx, &exceptionValue.toObject()); + if (JSObject* excStack = JS::ExceptionStackOrNull(exceptionObject)) { + // At this point we know exceptionObject is a possibly-wrapped + // js::ErrorObject that has excStack as stack. excStack might also be a CCW, + // but excStack must be same-compartment with the unwrapped ErrorObject. + // Return the ErrorObject's global as stackGlobal. This matches what we do + // in the ErrorObject's |.stack| getter and ensures stackObj and stackGlobal + // are same-compartment. + JSObject* unwrappedException = js::UncheckedUnwrap(exceptionObject); + stackObj.set(excStack); + stackGlobal.set(JS::GetNonCCWObjectGlobal(unwrappedException)); + return; + } + + // It is not a JS Exception, try DOM Exception. + RefPtr<Exception> exception; + UNWRAP_OBJECT(DOMException, exceptionObject, exception); + if (!exception) { + // Not a DOM Exception, try XPC Exception. + UNWRAP_OBJECT(Exception, exceptionObject, exception); + if (!exception) { + // As above, use the stack provided by the JS engine, if available. + if (exceptionStack) { + stackObj.set(exceptionStack); + stackGlobal.set(JS::GetNonCCWObjectGlobal(exceptionStack)); + } + return; + } + } + + nsCOMPtr<nsIStackFrame> stack = exception->GetLocation(); + if (!stack) { + return; + } + JS::Rooted<JS::Value> value(rcx); + stack->GetNativeSavedFrame(&value); + if (value.isObject()) { + stackObj.set(&value.toObject()); + MOZ_ASSERT(JS::IsUnwrappedSavedFrame(stackObj)); + stackGlobal.set(JS::GetNonCCWObjectGlobal(stackObj)); + return; + } +} + +} /* namespace xpc */ + +static TimeDuration GetCollectionTimeDelta() { + static TimeStamp sFirstCollectionTime; + TimeStamp now = TimeStamp::Now(); + if (sFirstCollectionTime) { + return now - sFirstCollectionTime; + } + sFirstCollectionTime = now; + return TimeDuration(); +} + +class nsJSEnvironmentObserver final : public nsIObserver { + ~nsJSEnvironmentObserver() = default; + + public: + NS_DECL_ISUPPORTS + NS_DECL_NSIOBSERVER +}; + +NS_IMPL_ISUPPORTS(nsJSEnvironmentObserver, nsIObserver) + +NS_IMETHODIMP +nsJSEnvironmentObserver::Observe(nsISupports* aSubject, const char* aTopic, + const char16_t* aData) { + if (!nsCRT::strcmp(aTopic, "memory-pressure")) { + if (StaticPrefs::javascript_options_gc_on_memory_pressure()) { + if (sShuttingDown) { + // Don't GC/CC if we're already shutting down. + return NS_OK; + } + nsDependentString data(aData); + if (data.EqualsLiteral("low-memory-ongoing")) { + // Don't GC/CC if we are in an ongoing low-memory state since its very + // slow and it likely won't help us anyway. + return NS_OK; + } + if (data.EqualsLiteral("heap-minimize")) { + // heap-minimize notifiers expect this to run synchronously + nsJSContext::DoLowMemoryGC(); + return NS_OK; + } + if (data.EqualsLiteral("low-memory")) { + nsJSContext::SetLowMemoryState(true); + } + // Asynchronously GC. + nsJSContext::LowMemoryGC(); + } + } else if (!nsCRT::strcmp(aTopic, "memory-pressure-stop")) { + nsJSContext::SetLowMemoryState(false); + } else if (!nsCRT::strcmp(aTopic, "user-interaction-inactive")) { + sScheduler->UserIsInactive(); + } else if (!nsCRT::strcmp(aTopic, "user-interaction-active")) { + sScheduler->UserIsActive(); + } else if (!nsCRT::strcmp(aTopic, "quit-application") || + !nsCRT::strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) || + !nsCRT::strcmp(aTopic, "content-child-will-shutdown")) { + sShuttingDown = true; + sScheduler->Shutdown(); + } + + return NS_OK; +} + +/**************************************************************** + ************************** AutoFree **************************** + ****************************************************************/ + +class AutoFree { + public: + explicit AutoFree(void* aPtr) : mPtr(aPtr) {} + ~AutoFree() { + if (mPtr) free(mPtr); + } + void Invalidate() { mPtr = nullptr; } + + private: + void* mPtr; +}; + +// A utility function for script languages to call. Although it looks small, +// the use of nsIDocShell and nsPresContext triggers a huge number of +// dependencies that most languages would not otherwise need. +// XXXmarkh - This function is mis-placed! +bool NS_HandleScriptError(nsIScriptGlobalObject* aScriptGlobal, + const ErrorEventInit& aErrorEventInit, + nsEventStatus* aStatus) { + bool called = false; + nsCOMPtr<nsPIDOMWindowInner> win(do_QueryInterface(aScriptGlobal)); + nsIDocShell* docShell = win ? win->GetDocShell() : nullptr; + if (docShell) { + RefPtr<nsPresContext> presContext = docShell->GetPresContext(); + + static int32_t errorDepth; // Recursion prevention + ++errorDepth; + + if (errorDepth < 2) { + // Dispatch() must be synchronous for the recursion block + // (errorDepth) to work. + RefPtr<ErrorEvent> event = ErrorEvent::Constructor( + nsGlobalWindowInner::Cast(win), u"error"_ns, aErrorEventInit); + event->SetTrusted(true); + + // MOZ_KnownLive due to bug 1506441 + EventDispatcher::DispatchDOMEvent( + MOZ_KnownLive(nsGlobalWindowInner::Cast(win)), nullptr, event, + presContext, aStatus); + called = true; + } + --errorDepth; + } + return called; +} + +class ScriptErrorEvent : public Runnable { + public: + ScriptErrorEvent(nsPIDOMWindowInner* aWindow, JS::RootingContext* aRootingCx, + xpc::ErrorReport* aReport, JS::Handle<JS::Value> aError, + JS::Handle<JSObject*> aErrorStack) + : mozilla::Runnable("ScriptErrorEvent"), + mWindow(aWindow), + mReport(aReport), + mError(aRootingCx, aError), + mErrorStack(aRootingCx, aErrorStack) {} + + // TODO: Convert this to MOZ_CAN_RUN_SCRIPT (bug 1415230, bug 1535398) + MOZ_CAN_RUN_SCRIPT_BOUNDARY NS_IMETHOD Run() override { + nsEventStatus status = nsEventStatus_eIgnore; + nsCOMPtr<nsPIDOMWindowInner> win = mWindow; + MOZ_ASSERT(win); + MOZ_ASSERT(NS_IsMainThread()); + // First, notify the DOM that we have a script error, but only if + // our window is still the current inner. + JS::RootingContext* rootingCx = RootingCx(); + if (win->IsCurrentInnerWindow() && win->GetDocShell() && + !sHandlingScriptError) { + AutoRestore<bool> recursionGuard(sHandlingScriptError); + sHandlingScriptError = true; + + RefPtr<nsPresContext> presContext = win->GetDocShell()->GetPresContext(); + + RootedDictionary<ErrorEventInit> init(rootingCx); + init.mCancelable = true; + init.mFilename = mReport->mFileName; + init.mBubbles = true; + + constexpr auto xoriginMsg = u"Script error."_ns; + if (!mReport->mIsMuted) { + init.mMessage = mReport->mErrorMsg; + init.mLineno = mReport->mLineNumber; + init.mColno = mReport->mColumn; + init.mError = mError; + } else { + NS_WARNING("Not same origin error!"); + init.mMessage = xoriginMsg; + init.mLineno = 0; + } + + RefPtr<ErrorEvent> event = ErrorEvent::Constructor( + nsGlobalWindowInner::Cast(win), u"error"_ns, init); + event->SetTrusted(true); + + // MOZ_KnownLive due to bug 1506441 + EventDispatcher::DispatchDOMEvent( + MOZ_KnownLive(nsGlobalWindowInner::Cast(win)), nullptr, event, + presContext, &status); + } + + if (status != nsEventStatus_eConsumeNoDefault) { + JS::Rooted<JSObject*> stack(rootingCx); + JS::Rooted<JSObject*> stackGlobal(rootingCx); + xpc::FindExceptionStackForConsoleReport(win, mError, mErrorStack, &stack, + &stackGlobal); + JS::Rooted<Maybe<JS::Value>> exception(rootingCx, Some(mError)); + nsGlobalWindowInner* inner = nsGlobalWindowInner::Cast(win); + mReport->LogToConsoleWithStack(inner, exception, stack, stackGlobal); + } + + return NS_OK; + } + + private: + nsCOMPtr<nsPIDOMWindowInner> mWindow; + RefPtr<xpc::ErrorReport> mReport; + JS::PersistentRooted<JS::Value> mError; + JS::PersistentRooted<JSObject*> mErrorStack; + + static bool sHandlingScriptError; +}; + +bool ScriptErrorEvent::sHandlingScriptError = false; + +// This temporarily lives here to avoid code churn. It will go away entirely +// soon. +namespace xpc { + +void DispatchScriptErrorEvent(nsPIDOMWindowInner* win, + JS::RootingContext* rootingCx, + xpc::ErrorReport* xpcReport, + JS::Handle<JS::Value> exception, + JS::Handle<JSObject*> exceptionStack) { + nsContentUtils::AddScriptRunner(new ScriptErrorEvent( + win, rootingCx, xpcReport, exception, exceptionStack)); +} + +} /* namespace xpc */ + +#ifdef DEBUG +// A couple of useful functions to call when you're debugging. +nsGlobalWindowInner* JSObject2Win(JSObject* obj) { + return xpc::WindowOrNull(obj); +} + +template <typename T> +void PrintWinURI(T* win) { + if (!win) { + printf("No window passed in.\n"); + return; + } + + nsCOMPtr<Document> doc = win->GetExtantDoc(); + if (!doc) { + printf("No document in the window.\n"); + return; + } + + nsIURI* uri = doc->GetDocumentURI(); + if (!uri) { + printf("Document doesn't have a URI.\n"); + return; + } + + printf("%s\n", uri->GetSpecOrDefault().get()); +} + +void PrintWinURIInner(nsGlobalWindowInner* aWin) { return PrintWinURI(aWin); } + +void PrintWinURIOuter(nsGlobalWindowOuter* aWin) { return PrintWinURI(aWin); } + +template <typename T> +void PrintWinCodebase(T* win) { + if (!win) { + printf("No window passed in.\n"); + return; + } + + nsIPrincipal* prin = win->GetPrincipal(); + if (!prin) { + printf("Window doesn't have principals.\n"); + return; + } + if (prin->IsSystemPrincipal()) { + printf("No URI, it's the system principal.\n"); + return; + } + nsCString spec; + prin->GetAsciiSpec(spec); + printf("%s\n", spec.get()); +} + +void PrintWinCodebaseInner(nsGlobalWindowInner* aWin) { + return PrintWinCodebase(aWin); +} + +void PrintWinCodebaseOuter(nsGlobalWindowOuter* aWin) { + return PrintWinCodebase(aWin); +} + +void DumpString(const nsAString& str) { + printf("%s\n", NS_ConvertUTF16toUTF8(str).get()); +} +#endif + +nsJSContext::nsJSContext(bool aGCOnDestruction, + nsIScriptGlobalObject* aGlobalObject) + : mWindowProxy(nullptr), + mGCOnDestruction(aGCOnDestruction), + mGlobalObjectRef(aGlobalObject) { + EnsureStatics(); + + mProcessingScriptTag = false; + HoldJSObjects(this); +} + +nsJSContext::~nsJSContext() { + mGlobalObjectRef = nullptr; + + Destroy(); +} + +void nsJSContext::Destroy() { + if (mGCOnDestruction) { + sScheduler->PokeGC(JS::GCReason::NSJSCONTEXT_DESTROY, mWindowProxy); + } + + DropJSObjects(this); +} + +// QueryInterface implementation for nsJSContext +NS_IMPL_CYCLE_COLLECTION_CLASS(nsJSContext) + +NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsJSContext) + NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mWindowProxy) +NS_IMPL_CYCLE_COLLECTION_TRACE_END + +NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsJSContext) + tmp->mGCOnDestruction = false; + tmp->mWindowProxy = nullptr; + tmp->Destroy(); + NS_IMPL_CYCLE_COLLECTION_UNLINK(mGlobalObjectRef) +NS_IMPL_CYCLE_COLLECTION_UNLINK_END +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsJSContext) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mGlobalObjectRef) +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END + +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsJSContext) + NS_INTERFACE_MAP_ENTRY(nsIScriptContext) + NS_INTERFACE_MAP_ENTRY(nsISupports) +NS_INTERFACE_MAP_END + +NS_IMPL_CYCLE_COLLECTING_ADDREF(nsJSContext) +NS_IMPL_CYCLE_COLLECTING_RELEASE(nsJSContext) + +#ifdef DEBUG +bool AtomIsEventHandlerName(nsAtom* aName) { + const char16_t* name = aName->GetUTF16String(); + + const char16_t* cp; + char16_t c; + for (cp = name; *cp != '\0'; ++cp) { + c = *cp; + if ((c < 'A' || c > 'Z') && (c < 'a' || c > 'z')) return false; + } + + return true; +} +#endif + +nsIScriptGlobalObject* nsJSContext::GetGlobalObject() { + // Note: this could probably be simplified somewhat more; see bug 974327 + // comments 1 and 3. + if (!mWindowProxy) { + return nullptr; + } + + MOZ_ASSERT(mGlobalObjectRef); + return mGlobalObjectRef; +} + +nsresult nsJSContext::SetProperty(JS::Handle<JSObject*> aTarget, + const char* aPropName, nsISupports* aArgs) { + AutoJSAPI jsapi; + if (NS_WARN_IF(!jsapi.Init(GetGlobalObject()))) { + return NS_ERROR_FAILURE; + } + JSContext* cx = jsapi.cx(); + + JS::RootedVector<JS::Value> args(cx); + + JS::Rooted<JSObject*> global(cx, GetWindowProxy()); + nsresult rv = ConvertSupportsTojsvals(cx, aArgs, global, &args); + NS_ENSURE_SUCCESS(rv, rv); + + // got the arguments, now attach them. + + for (uint32_t i = 0; i < args.length(); ++i) { + if (!JS_WrapValue(cx, args[i])) { + return NS_ERROR_FAILURE; + } + } + + JS::Rooted<JSObject*> array(cx, JS::NewArrayObject(cx, args)); + if (!array) { + return NS_ERROR_FAILURE; + } + + return JS_DefineProperty(cx, aTarget, aPropName, array, 0) ? NS_OK + : NS_ERROR_FAILURE; +} + +nsresult nsJSContext::ConvertSupportsTojsvals( + JSContext* aCx, nsISupports* aArgs, JS::Handle<JSObject*> aScope, + JS::MutableHandleVector<JS::Value> aArgsOut) { + nsresult rv = NS_OK; + + // If the array implements nsIJSArgArray, copy the contents and return. + nsCOMPtr<nsIJSArgArray> fastArray = do_QueryInterface(aArgs); + if (fastArray) { + uint32_t argc; + JS::Value* argv; + rv = fastArray->GetArgs(&argc, reinterpret_cast<void**>(&argv)); + if (NS_SUCCEEDED(rv) && !aArgsOut.append(argv, argc)) { + rv = NS_ERROR_OUT_OF_MEMORY; + } + return rv; + } + + // Take the slower path converting each item. + // Handle only nsIArray and nsIVariant. nsIArray is only needed for + // SetProperty('arguments', ...); + + nsIXPConnect* xpc = nsContentUtils::XPConnect(); + NS_ENSURE_TRUE(xpc, NS_ERROR_UNEXPECTED); + + if (!aArgs) return NS_OK; + uint32_t argCount; + // This general purpose function may need to convert an arg array + // (window.arguments, event-handler args) and a generic property. + nsCOMPtr<nsIArray> argsArray(do_QueryInterface(aArgs)); + + if (argsArray) { + rv = argsArray->GetLength(&argCount); + NS_ENSURE_SUCCESS(rv, rv); + if (argCount == 0) return NS_OK; + } else { + argCount = 1; // the nsISupports which is not an array + } + + // Use the caller's auto guards to release and unroot. + if (!aArgsOut.resize(argCount)) { + return NS_ERROR_OUT_OF_MEMORY; + } + + if (argsArray) { + for (uint32_t argCtr = 0; argCtr < argCount && NS_SUCCEEDED(rv); argCtr++) { + nsCOMPtr<nsISupports> arg; + JS::MutableHandle<JS::Value> thisVal = aArgsOut[argCtr]; + argsArray->QueryElementAt(argCtr, NS_GET_IID(nsISupports), + getter_AddRefs(arg)); + if (!arg) { + thisVal.setNull(); + continue; + } + nsCOMPtr<nsIVariant> variant(do_QueryInterface(arg)); + if (variant != nullptr) { + rv = xpc->VariantToJS(aCx, aScope, variant, thisVal); + } else { + // And finally, support the nsISupportsPrimitives supplied + // by the AppShell. It generally will pass only strings, but + // as we have code for handling all, we may as well use it. + rv = AddSupportsPrimitiveTojsvals(aCx, arg, thisVal.address()); + if (rv == NS_ERROR_NO_INTERFACE) { + // something else - probably an event object or similar - + // just wrap it. +#ifdef DEBUG + // but first, check its not another nsISupportsPrimitive, as + // these are now deprecated for use with script contexts. + nsCOMPtr<nsISupportsPrimitive> prim(do_QueryInterface(arg)); + NS_ASSERTION(prim == nullptr, + "Don't pass nsISupportsPrimitives - use nsIVariant!"); +#endif + JSAutoRealm ar(aCx, aScope); + rv = nsContentUtils::WrapNative(aCx, arg, thisVal); + } + } + } + } else { + nsCOMPtr<nsIVariant> variant = do_QueryInterface(aArgs); + if (variant) { + rv = xpc->VariantToJS(aCx, aScope, variant, aArgsOut[0]); + } else { + NS_ERROR("Not an array, not an interface?"); + rv = NS_ERROR_UNEXPECTED; + } + } + return rv; +} + +// This really should go into xpconnect somewhere... +nsresult nsJSContext::AddSupportsPrimitiveTojsvals(JSContext* aCx, + nsISupports* aArg, + JS::Value* aArgv) { + MOZ_ASSERT(aArg, "Empty arg"); + + nsCOMPtr<nsISupportsPrimitive> argPrimitive(do_QueryInterface(aArg)); + if (!argPrimitive) return NS_ERROR_NO_INTERFACE; + + uint16_t type; + argPrimitive->GetType(&type); + + switch (type) { + case nsISupportsPrimitive::TYPE_CSTRING: { + nsCOMPtr<nsISupportsCString> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + nsAutoCString data; + + p->GetData(data); + + JSString* str = ::JS_NewStringCopyN(aCx, data.get(), data.Length()); + NS_ENSURE_TRUE(str, NS_ERROR_OUT_OF_MEMORY); + + aArgv->setString(str); + + break; + } + case nsISupportsPrimitive::TYPE_STRING: { + nsCOMPtr<nsISupportsString> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + nsAutoString data; + + p->GetData(data); + + // cast is probably safe since wchar_t and char16_t are expected + // to be equivalent; both unsigned 16-bit entities + JSString* str = ::JS_NewUCStringCopyN(aCx, data.get(), data.Length()); + NS_ENSURE_TRUE(str, NS_ERROR_OUT_OF_MEMORY); + + aArgv->setString(str); + break; + } + case nsISupportsPrimitive::TYPE_PRBOOL: { + nsCOMPtr<nsISupportsPRBool> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + bool data; + + p->GetData(&data); + + aArgv->setBoolean(data); + + break; + } + case nsISupportsPrimitive::TYPE_PRUINT8: { + nsCOMPtr<nsISupportsPRUint8> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + uint8_t data; + + p->GetData(&data); + + aArgv->setInt32(data); + + break; + } + case nsISupportsPrimitive::TYPE_PRUINT16: { + nsCOMPtr<nsISupportsPRUint16> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + uint16_t data; + + p->GetData(&data); + + aArgv->setInt32(data); + + break; + } + case nsISupportsPrimitive::TYPE_PRUINT32: { + nsCOMPtr<nsISupportsPRUint32> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + uint32_t data; + + p->GetData(&data); + + aArgv->setInt32(data); + + break; + } + case nsISupportsPrimitive::TYPE_CHAR: { + nsCOMPtr<nsISupportsChar> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + char data; + + p->GetData(&data); + + JSString* str = ::JS_NewStringCopyN(aCx, &data, 1); + NS_ENSURE_TRUE(str, NS_ERROR_OUT_OF_MEMORY); + + aArgv->setString(str); + + break; + } + case nsISupportsPrimitive::TYPE_PRINT16: { + nsCOMPtr<nsISupportsPRInt16> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + int16_t data; + + p->GetData(&data); + + aArgv->setInt32(data); + + break; + } + case nsISupportsPrimitive::TYPE_PRINT32: { + nsCOMPtr<nsISupportsPRInt32> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + int32_t data; + + p->GetData(&data); + + aArgv->setInt32(data); + + break; + } + case nsISupportsPrimitive::TYPE_FLOAT: { + nsCOMPtr<nsISupportsFloat> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + float data; + + p->GetData(&data); + + *aArgv = ::JS_NumberValue(data); + + break; + } + case nsISupportsPrimitive::TYPE_DOUBLE: { + nsCOMPtr<nsISupportsDouble> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + double data; + + p->GetData(&data); + + *aArgv = ::JS_NumberValue(data); + + break; + } + case nsISupportsPrimitive::TYPE_INTERFACE_POINTER: { + nsCOMPtr<nsISupportsInterfacePointer> p(do_QueryInterface(argPrimitive)); + NS_ENSURE_TRUE(p, NS_ERROR_UNEXPECTED); + + nsCOMPtr<nsISupports> data; + nsIID* iid = nullptr; + + p->GetData(getter_AddRefs(data)); + p->GetDataIID(&iid); + NS_ENSURE_TRUE(iid, NS_ERROR_UNEXPECTED); + + AutoFree iidGuard(iid); // Free iid upon destruction. + + JS::Rooted<JSObject*> scope(aCx, GetWindowProxy()); + JS::Rooted<JS::Value> v(aCx); + JSAutoRealm ar(aCx, scope); + nsresult rv = nsContentUtils::WrapNative(aCx, data, iid, &v); + NS_ENSURE_SUCCESS(rv, rv); + + *aArgv = v; + + break; + } + case nsISupportsPrimitive::TYPE_ID: + case nsISupportsPrimitive::TYPE_PRUINT64: + case nsISupportsPrimitive::TYPE_PRINT64: + case nsISupportsPrimitive::TYPE_PRTIME: { + NS_WARNING("Unsupported primitive type used"); + aArgv->setNull(); + break; + } + default: { + NS_WARNING("Unknown primitive type used"); + aArgv->setNull(); + break; + } + } + return NS_OK; +} + +#ifdef MOZ_JPROF + +# include <signal.h> + +inline bool IsJProfAction(struct sigaction* action) { + return (action->sa_sigaction && + (action->sa_flags & (SA_RESTART | SA_SIGINFO)) == + (SA_RESTART | SA_SIGINFO)); +} + +void NS_JProfStartProfiling(); +void NS_JProfStopProfiling(); +void NS_JProfClearCircular(); + +static bool JProfStartProfilingJS(JSContext* cx, unsigned argc, JS::Value* vp) { + NS_JProfStartProfiling(); + return true; +} + +void NS_JProfStartProfiling() { + // Figure out whether we're dealing with SIGPROF, SIGALRM, or + // SIGPOLL profiling (SIGALRM for JP_REALTIME, SIGPOLL for + // JP_RTC_HZ) + struct sigaction action; + + // Must check ALRM before PROF since both are enabled for real-time + sigaction(SIGALRM, nullptr, &action); + // printf("SIGALRM: %p, flags = %x\n",action.sa_sigaction,action.sa_flags); + if (IsJProfAction(&action)) { + // printf("Beginning real-time jprof profiling.\n"); + raise(SIGALRM); + return; + } + + sigaction(SIGPROF, nullptr, &action); + // printf("SIGPROF: %p, flags = %x\n",action.sa_sigaction,action.sa_flags); + if (IsJProfAction(&action)) { + // printf("Beginning process-time jprof profiling.\n"); + raise(SIGPROF); + return; + } + + sigaction(SIGPOLL, nullptr, &action); + // printf("SIGPOLL: %p, flags = %x\n",action.sa_sigaction,action.sa_flags); + if (IsJProfAction(&action)) { + // printf("Beginning rtc-based jprof profiling.\n"); + raise(SIGPOLL); + return; + } + + printf("Could not start jprof-profiling since JPROF_FLAGS was not set.\n"); +} + +static bool JProfStopProfilingJS(JSContext* cx, unsigned argc, JS::Value* vp) { + NS_JProfStopProfiling(); + return true; +} + +void NS_JProfStopProfiling() { + raise(SIGUSR1); + // printf("Stopped jprof profiling.\n"); +} + +static bool JProfClearCircularJS(JSContext* cx, unsigned argc, JS::Value* vp) { + NS_JProfClearCircular(); + return true; +} + +void NS_JProfClearCircular() { + raise(SIGUSR2); + // printf("cleared jprof buffer\n"); +} + +static bool JProfSaveCircularJS(JSContext* cx, unsigned argc, JS::Value* vp) { + // Not ideal... + NS_JProfStopProfiling(); + NS_JProfStartProfiling(); + return true; +} + +static const JSFunctionSpec JProfFunctions[] = { + JS_FN("JProfStartProfiling", JProfStartProfilingJS, 0, 0), + JS_FN("JProfStopProfiling", JProfStopProfilingJS, 0, 0), + JS_FN("JProfClearCircular", JProfClearCircularJS, 0, 0), + JS_FN("JProfSaveCircular", JProfSaveCircularJS, 0, 0), JS_FS_END}; + +#endif /* defined(MOZ_JPROF) */ + +nsresult nsJSContext::InitClasses(JS::Handle<JSObject*> aGlobalObj) { + AutoJSAPI jsapi; + jsapi.Init(); + JSContext* cx = jsapi.cx(); + JSAutoRealm ar(cx, aGlobalObj); + +#ifdef MOZ_JPROF + // Attempt to initialize JProf functions + ::JS_DefineFunctions(cx, aGlobalObj, JProfFunctions); +#endif + + return NS_OK; +} + +bool nsJSContext::GetProcessingScriptTag() { return mProcessingScriptTag; } + +void nsJSContext::SetProcessingScriptTag(bool aFlag) { + mProcessingScriptTag = aFlag; +} + +// static +void nsJSContext::SetLowMemoryState(bool aState) { + JSContext* cx = danger::GetJSContext(); + JS::SetLowMemoryState(cx, aState); +} + +static void GarbageCollectImpl(JS::GCReason aReason, + nsJSContext::IsShrinking aShrinking, + const js::SliceBudget& aBudget) { + AUTO_PROFILER_LABEL_DYNAMIC_CSTR_NONSENSITIVE( + "nsJSContext::GarbageCollectNow", GCCC, JS::ExplainGCReason(aReason)); + + bool wantIncremental = !aBudget.isUnlimited(); + + // We use danger::GetJSContext() since AutoJSAPI will assert if the current + // thread's context is null (such as during shutdown). + JSContext* cx = danger::GetJSContext(); + + if (!nsContentUtils::XPConnect() || !cx) { + return; + } + + if (sScheduler->InIncrementalGC() && wantIncremental) { + // We're in the middle of incremental GC. Do another slice. + JS::PrepareForIncrementalGC(cx); + JS::IncrementalGCSlice(cx, aReason, aBudget); + return; + } + + JS::GCOptions options = aShrinking == nsJSContext::ShrinkingGC + ? JS::GCOptions::Shrink + : JS::GCOptions::Normal; + + if (!wantIncremental || aReason == JS::GCReason::FULL_GC_TIMER) { + sScheduler->SetNeedsFullGC(); + } + + if (sScheduler->NeedsFullGC()) { + JS::PrepareForFullGC(cx); + } + + if (wantIncremental) { + // Incremental GC slices will be triggered by the GC Runner. If one doesn't + // already exist, create it in the GC_SLICE_END callback for the first + // slice being executed here. + JS::StartIncrementalGC(cx, options, aReason, aBudget); + } else { + JS::NonIncrementalGC(cx, options, aReason); + } +} + +// static +void nsJSContext::GarbageCollectNow(JS::GCReason aReason, + IsShrinking aShrinking) { + GarbageCollectImpl(aReason, aShrinking, js::SliceBudget::unlimited()); +} + +// static +void nsJSContext::RunIncrementalGCSlice(JS::GCReason aReason, + IsShrinking aShrinking, + js::SliceBudget& aBudget) { + AUTO_PROFILER_LABEL_RELEVANT_FOR_JS("Incremental GC", GCCC); + GarbageCollectImpl(aReason, aShrinking, aBudget); +} + +static void FinishAnyIncrementalGC() { + AUTO_PROFILER_LABEL("FinishAnyIncrementalGC", GCCC); + + if (sScheduler->InIncrementalGC()) { + AutoJSAPI jsapi; + jsapi.Init(); + + // We're in the middle of an incremental GC, so finish it. + JS::PrepareForIncrementalGC(jsapi.cx()); + JS::FinishIncrementalGC(jsapi.cx(), JS::GCReason::CC_FORCED); + } +} + +namespace geckoprofiler::markers { +class CCSliceMarker : public BaseMarkerType<CCSliceMarker> { + public: + static constexpr const char* Name = "CCSlice"; + static constexpr const char* Description = + "Information for an individual CC slice."; + + using MS = MarkerSchema; + static constexpr MS::PayloadField PayloadFields[] = { + {"idle", MS::InputType::Boolean, "Idle", MS::Format::Integer}}; + + static constexpr MS::Location Locations[] = {MS::Location::MarkerChart, + MS::Location::MarkerTable, + MS::Location::TimelineMemory}; + static constexpr const char* AllLabels = + "{marker.name} (idle={marker.data.idle})"; + + static constexpr MS::ETWMarkerGroup Group = MS::ETWMarkerGroup::Memory; + + static void StreamJSONMarkerData( + mozilla::baseprofiler::SpliceableJSONWriter& aWriter, + bool aIsDuringIdle) { + StreamJSONMarkerDataImpl(aWriter, aIsDuringIdle); + } +}; +} // namespace geckoprofiler::markers + +static void FireForgetSkippable(bool aRemoveChildless, TimeStamp aDeadline) { + TimeStamp startTimeStamp = TimeStamp::Now(); + FinishAnyIncrementalGC(); + + uint32_t suspectedBefore = nsCycleCollector_suspectedCount(); + js::SliceBudget budget = + sScheduler->ComputeForgetSkippableBudget(startTimeStamp, aDeadline); + bool earlyForgetSkippable = sScheduler->IsEarlyForgetSkippable(); + nsCycleCollector_forgetSkippable(budget, aRemoveChildless, + earlyForgetSkippable); + TimeStamp now = TimeStamp::Now(); + uint32_t removedPurples = sScheduler->NoteForgetSkippableComplete( + now, suspectedBefore, nsCycleCollector_suspectedCount()); + + TimeDuration duration = now - startTimeStamp; + + sCCStats.AfterForgetSkippable(duration, removedPurples); + + if (duration.ToSeconds()) { + TimeDuration idleDuration; + if (!aDeadline.IsNull()) { + if (aDeadline < now) { + // This slice overflowed the idle period. + if (aDeadline > startTimeStamp) { + idleDuration = aDeadline - startTimeStamp; + } + } else { + idleDuration = duration; + } + } + + uint32_t percent = + uint32_t(idleDuration.ToSeconds() / duration.ToSeconds() * 100); + Telemetry::Accumulate(Telemetry::FORGET_SKIPPABLE_DURING_IDLE, percent); + } + + PROFILER_MARKER("ForgetSkippable", GCCC, + MarkerTiming::IntervalUntilNowFrom(startTimeStamp), + CCSliceMarker, !aDeadline.IsNull()); +} + +MOZ_ALWAYS_INLINE +static TimeDuration TimeBetween(TimeStamp aStart, TimeStamp aEnd) { + MOZ_ASSERT(aEnd >= aStart); + return aEnd - aStart; +} + +static TimeDuration TimeUntilNow(TimeStamp start) { + if (start.IsNull()) { + return TimeDuration(); + } + return TimeBetween(start, TimeStamp::Now()); +} + +void CycleCollectorStats::Init() { + Clear(); + + char* env = getenv("MOZ_CCTIMER"); + if (!env) { + return; + } + if (strcmp(env, "none") == 0) { + mFile = nullptr; + } else if (strcmp(env, "stdout") == 0) { + mFile = stdout; + } else if (strcmp(env, "stderr") == 0) { + mFile = stderr; + } else { + mFile = fopen(env, "a"); + if (!mFile) { + MOZ_CRASH("Failed to open MOZ_CCTIMER log file."); + } + } +} + +void CycleCollectorStats::Clear() { + if (mFile && mFile != stdout && mFile != stderr) { + fclose(mFile); + } + *this = CycleCollectorStats(); +} + +void CycleCollectorStats::AfterCycleCollectionSlice() { + if (mBeginSliceTime.IsNull()) { + // We already called this method from EndCycleCollectionCallback for this + // slice. + return; + } + + mEndSliceTime = TimeStamp::Now(); + TimeDuration duration = mEndSliceTime - mBeginSliceTime; + + PROFILER_MARKER( + "CCSlice", GCCC, MarkerTiming::Interval(mBeginSliceTime, mEndSliceTime), + CCSliceMarker, !mIdleDeadline.IsNull() && mIdleDeadline >= mEndSliceTime); + + if (duration.ToSeconds()) { + TimeDuration idleDuration; + if (!mIdleDeadline.IsNull()) { + if (mIdleDeadline < mEndSliceTime) { + // This slice overflowed the idle period. + if (mIdleDeadline > mBeginSliceTime) { + idleDuration = mIdleDeadline - mBeginSliceTime; + } + } else { + idleDuration = duration; + } + } + + uint32_t percent = + uint32_t(idleDuration.ToSeconds() / duration.ToSeconds() * 100); + Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_SLICE_DURING_IDLE, + percent); + } + + TimeDuration sliceTime = TimeBetween(mBeginSliceTime, mEndSliceTime); + mMaxSliceTime = std::max(mMaxSliceTime, sliceTime); + mMaxSliceTimeSinceClear = std::max(mMaxSliceTimeSinceClear, sliceTime); + mTotalSliceTime += sliceTime; + mBeginSliceTime = TimeStamp(); +} + +void CycleCollectorStats::PrepareForCycleCollection(TimeStamp aNow) { + mBeginTime = aNow; + mSuspected = nsCycleCollector_suspectedCount(); +} + +void CycleCollectorStats::AfterPrepareForCycleCollectionSlice( + TimeStamp aDeadline, TimeStamp aBeginTime, TimeStamp aMaybeAfterGCTime) { + mBeginSliceTime = aBeginTime; + mIdleDeadline = aDeadline; + + if (!aMaybeAfterGCTime.IsNull()) { + mAnyLockedOut = true; + mMaxGCDuration = std::max(mMaxGCDuration, aMaybeAfterGCTime - aBeginTime); + } +} + +void CycleCollectorStats::AfterSyncForgetSkippable(TimeStamp beginTime) { + mMaxSkippableDuration = + std::max(mMaxSkippableDuration, TimeUntilNow(beginTime)); + mRanSyncForgetSkippable = true; +} + +void CycleCollectorStats::AfterForgetSkippable(TimeDuration duration, + uint32_t aRemovedPurples) { + if (!mMinForgetSkippableTime || mMinForgetSkippableTime > duration) { + mMinForgetSkippableTime = duration; + } + if (!mMaxForgetSkippableTime || mMaxForgetSkippableTime < duration) { + mMaxForgetSkippableTime = duration; + } + mTotalForgetSkippableTime += duration; + ++mForgetSkippableBeforeCC; + + mRemovedPurples += aRemovedPurples; +} + +void CycleCollectorStats::SendTelemetry(TimeDuration aCCNowDuration, + TimeStamp aPrevCCEnd) const { + Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_FINISH_IGC, mAnyLockedOut); + Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_SYNC_SKIPPABLE, + mRanSyncForgetSkippable); + Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_FULL, + aCCNowDuration.ToMilliseconds()); + Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_MAX_PAUSE, + mMaxSliceTime.ToMilliseconds()); + + if (!aPrevCCEnd.IsNull()) { + TimeDuration timeBetween = TimeBetween(aPrevCCEnd, mBeginTime); + Telemetry::Accumulate(Telemetry::CYCLE_COLLECTOR_TIME_BETWEEN, + timeBetween.ToSeconds()); + } + + Telemetry::Accumulate(Telemetry::FORGET_SKIPPABLE_MAX, + mMaxForgetSkippableTime.ToMilliseconds()); +} + +void CycleCollectorStats::MaybeLogStats(const CycleCollectorResults& aResults, + uint32_t aCleanups) const { + if (!StaticPrefs::javascript_options_mem_log() && !sCCStats.mFile) { + return; + } + + TimeDuration delta = GetCollectionTimeDelta(); + + nsCString mergeMsg; + if (aResults.mMergedZones) { + mergeMsg.AssignLiteral(" merged"); + } + + nsCString gcMsg; + if (aResults.mForcedGC) { + gcMsg.AssignLiteral(", forced a GC"); + } + + const char16_t* kFmt = + u"CC(T+%.1f)[%s-%i] max pause: %.fms, total time: %.fms, slices: %lu, " + u"suspected: %lu, visited: %lu RCed and %lu%s GCed, collected: %lu " + u"RCed and %lu GCed (%lu|%lu|%lu waiting for GC)%s\n" + u"ForgetSkippable %lu times before CC, min: %.f ms, max: %.f ms, avg: " + u"%.f ms, total: %.f ms, max sync: %.f ms, removed: %lu"; + nsString msg; + nsTextFormatter::ssprintf( + msg, kFmt, delta.ToMicroseconds() / PR_USEC_PER_SEC, + ProcessNameForCollectorLog(), getpid(), mMaxSliceTime.ToMilliseconds(), + mTotalSliceTime.ToMilliseconds(), aResults.mNumSlices, mSuspected, + aResults.mVisitedRefCounted, aResults.mVisitedGCed, mergeMsg.get(), + aResults.mFreedRefCounted, aResults.mFreedGCed, + sScheduler->mCCollectedWaitingForGC, + sScheduler->mCCollectedZonesWaitingForGC, + sScheduler->mLikelyShortLivingObjectsNeedingGC, gcMsg.get(), + mForgetSkippableBeforeCC, mMinForgetSkippableTime.ToMilliseconds(), + mMaxForgetSkippableTime.ToMilliseconds(), + mTotalForgetSkippableTime.ToMilliseconds() / aCleanups, + mTotalForgetSkippableTime.ToMilliseconds(), + mMaxSkippableDuration.ToMilliseconds(), mRemovedPurples); + if (StaticPrefs::javascript_options_mem_log()) { + nsCOMPtr<nsIConsoleService> cs = + do_GetService(NS_CONSOLESERVICE_CONTRACTID); + if (cs) { + cs->LogStringMessage(msg.get()); + } + } + if (mFile) { + fprintf(mFile, "%s\n", NS_ConvertUTF16toUTF8(msg).get()); + } +} + +void CycleCollectorStats::MaybeNotifyStats( + const CycleCollectorResults& aResults, TimeDuration aCCNowDuration, + uint32_t aCleanups) const { + if (!StaticPrefs::javascript_options_mem_notify()) { + return; + } + + const char16_t* kJSONFmt = + u"{ \"timestamp\": %llu, " + u"\"duration\": %.f, " + u"\"max_slice_pause\": %.f, " + u"\"total_slice_pause\": %.f, " + u"\"max_finish_gc_duration\": %.f, " + u"\"max_sync_skippable_duration\": %.f, " + u"\"suspected\": %lu, " + u"\"visited\": { " + u"\"RCed\": %lu, " + u"\"GCed\": %lu }, " + u"\"collected\": { " + u"\"RCed\": %lu, " + u"\"GCed\": %lu }, " + u"\"waiting_for_gc\": %lu, " + u"\"zones_waiting_for_gc\": %lu, " + u"\"short_living_objects_waiting_for_gc\": %lu, " + u"\"forced_gc\": %d, " + u"\"forget_skippable\": { " + u"\"times_before_cc\": %lu, " + u"\"min\": %.f, " + u"\"max\": %.f, " + u"\"avg\": %.f, " + u"\"total\": %.f, " + u"\"removed\": %lu } " + u"}"; + + nsString json; + nsTextFormatter::ssprintf( + json, kJSONFmt, PR_Now(), aCCNowDuration.ToMilliseconds(), + mMaxSliceTime.ToMilliseconds(), mTotalSliceTime.ToMilliseconds(), + mMaxGCDuration.ToMilliseconds(), mMaxSkippableDuration.ToMilliseconds(), + mSuspected, aResults.mVisitedRefCounted, aResults.mVisitedGCed, + aResults.mFreedRefCounted, aResults.mFreedGCed, + sScheduler->mCCollectedWaitingForGC, + sScheduler->mCCollectedZonesWaitingForGC, + sScheduler->mLikelyShortLivingObjectsNeedingGC, aResults.mForcedGC, + mForgetSkippableBeforeCC, mMinForgetSkippableTime.ToMilliseconds(), + mMaxForgetSkippableTime.ToMilliseconds(), + mTotalForgetSkippableTime.ToMilliseconds() / aCleanups, + mTotalForgetSkippableTime.ToMilliseconds(), mRemovedPurples); + nsCOMPtr<nsIObserverService> observerService = + mozilla::services::GetObserverService(); + if (observerService) { + observerService->NotifyObservers(nullptr, "cycle-collection-statistics", + json.get()); + } +} + +// static +void nsJSContext::CycleCollectNow(CCReason aReason, + nsICycleCollectorListener* aListener) { + if (!NS_IsMainThread()) { + return; + } + + AUTO_PROFILER_LABEL("nsJSContext::CycleCollectNow", GCCC); + + PrepareForCycleCollectionSlice(aReason, TimeStamp()); + nsCycleCollector_collect(aReason, aListener); + sCCStats.AfterCycleCollectionSlice(); +} + +// static +void nsJSContext::PrepareForCycleCollectionSlice(CCReason aReason, + TimeStamp aDeadline) { + TimeStamp beginTime = TimeStamp::Now(); + + // Before we begin the cycle collection, make sure there is no active GC. + TimeStamp afterGCTime; + if (sScheduler->InIncrementalGC()) { + FinishAnyIncrementalGC(); + afterGCTime = TimeStamp::Now(); + } + + if (!sScheduler->IsCollectingCycles()) { + sCCStats.PrepareForCycleCollection(beginTime); + sScheduler->NoteCCBegin(aReason, beginTime, + sCCStats.mForgetSkippableBeforeCC, + sCCStats.mSuspected, sCCStats.mRemovedPurples); + } + + sCCStats.AfterPrepareForCycleCollectionSlice(aDeadline, beginTime, + afterGCTime); +} + +// static +void nsJSContext::RunCycleCollectorSlice(CCReason aReason, + TimeStamp aDeadline) { + if (!NS_IsMainThread()) { + return; + } + + PrepareForCycleCollectionSlice(aReason, aDeadline); + + // Decide how long we want to budget for this slice. + if (sIncrementalCC) { + bool preferShorterSlices; + js::SliceBudget budget = sScheduler->ComputeCCSliceBudget( + aDeadline, sCCStats.mBeginTime, sCCStats.mEndSliceTime, + TimeStamp::Now(), &preferShorterSlices); + nsCycleCollector_collectSlice(budget, aReason, preferShorterSlices); + } else { + js::SliceBudget budget = js::SliceBudget::unlimited(); + nsCycleCollector_collectSlice(budget, aReason, false); + } + + sCCStats.AfterCycleCollectionSlice(); +} + +// static +void nsJSContext::RunCycleCollectorWorkSlice(int64_t aWorkBudget) { + if (!NS_IsMainThread()) { + return; + } + + AUTO_PROFILER_LABEL("nsJSContext::RunCycleCollectorWorkSlice", GCCC); + + PrepareForCycleCollectionSlice(CCReason::API, TimeStamp()); + + js::SliceBudget budget = js::SliceBudget(js::WorkBudget(aWorkBudget)); + nsCycleCollector_collectSlice(budget, CCReason::API); + + sCCStats.AfterCycleCollectionSlice(); +} + +void nsJSContext::ClearMaxCCSliceTime() { + sCCStats.mMaxSliceTimeSinceClear = TimeDuration(); +} + +uint32_t nsJSContext::GetMaxCCSliceTimeSinceClear() { + return sCCStats.mMaxSliceTimeSinceClear.ToMilliseconds(); +} + +// static +void nsJSContext::BeginCycleCollectionCallback(CCReason aReason) { + MOZ_ASSERT(NS_IsMainThread()); + + TimeStamp startTime = TimeStamp::Now(); + sCCStats.PrepareForCycleCollection(startTime); + + // Run forgetSkippable synchronously to reduce the size of the CC graph. This + // is particularly useful if we recently finished a GC. + if (sScheduler->IsEarlyForgetSkippable()) { + while (sScheduler->IsEarlyForgetSkippable()) { + FireForgetSkippable(false, TimeStamp()); + } + sCCStats.AfterSyncForgetSkippable(startTime); + } + + if (sShuttingDown) { + return; + } + + sScheduler->InitCCRunnerStateMachine( + mozilla::CCGCScheduler::CCRunnerState::CycleCollecting, aReason); + sScheduler->EnsureCCRunner(kICCIntersliceDelay, kIdleICCSliceBudget); +} + +// static +void nsJSContext::EndCycleCollectionCallback( + const CycleCollectorResults& aResults) { + MOZ_ASSERT(NS_IsMainThread()); + + sScheduler->KillCCRunner(); + + // Update timing information for the current slice before we log it, if + // we previously called PrepareForCycleCollectionSlice(). During shutdown + // CCs, this won't happen. + sCCStats.AfterCycleCollectionSlice(); + + TimeStamp endCCTimeStamp = TimeStamp::Now(); + TimeDuration ccNowDuration = TimeBetween(sCCStats.mBeginTime, endCCTimeStamp); + TimeStamp prevCCEnd = sScheduler->GetLastCCEndTime(); + + sScheduler->NoteCCEnd(aResults, endCCTimeStamp, sCCStats.mMaxSliceTime); + + // Log information about the CC via telemetry, JSON and the console. + + sCCStats.SendTelemetry(ccNowDuration, prevCCEnd); + + uint32_t cleanups = std::max(sCCStats.mForgetSkippableBeforeCC, 1u); + + sCCStats.MaybeLogStats(aResults, cleanups); + + sCCStats.MaybeNotifyStats(aResults, ccNowDuration, cleanups); + + // Update global state to indicate we have just run a cycle collection. + sCCStats.Clear(); + + // If we need a GC after this CC (typically because lots of GCed objects or + // zones have been collected in the CC), schedule it. + + if (sScheduler->NeedsGCAfterCC()) { + MOZ_ASSERT( + TimeDuration::FromMilliseconds( + StaticPrefs::javascript_options_gc_delay()) > kMaxICCDuration, + "A max duration ICC shouldn't reduce GC delay to 0"); + + TimeDuration delay; + if (aResults.mFreedGCed > 10000 && aResults.mFreedRefCounted > 10000) { + // If we collected lots of objects, trigger the next GC sooner so that + // GC can cut JS-to-native edges and native objects can be then deleted. + delay = TimeDuration::FromMilliseconds( + StaticPrefs::javascript_options_gc_delay_interslice()); + } else { + delay = TimeDuration::FromMilliseconds( + StaticPrefs::javascript_options_gc_delay()) - + std::min(ccNowDuration, kMaxICCDuration); + } + + sScheduler->PokeGC(JS::GCReason::CC_FINISHED, nullptr, delay); + } +#if defined(MOZ_MEMORY) + else if ( + StaticPrefs:: + dom_memory_foreground_content_processes_have_larger_page_cache()) { + jemalloc_free_dirty_pages(); + } +#endif +} + +/* static */ +bool CCGCScheduler::CCRunnerFired(TimeStamp aDeadline) { + AUTO_PROFILER_LABEL_RELEVANT_FOR_JS("Incremental CC", GCCC); + + bool didDoWork = false; + + // The CC/GC scheduler (sScheduler) decides what action(s) to take during + // this invocation of the CC runner. + // + // This may be zero, one, or multiple actions. (Zero is when CC is blocked by + // incremental GC, or when the scheduler determined that a CC is no longer + // needed.) Loop until the scheduler finishes this invocation by returning + // `Yield` in step.mYield. + CCRunnerStep step; + do { + step = sScheduler->AdvanceCCRunner(aDeadline, TimeStamp::Now(), + nsCycleCollector_suspectedCount()); + switch (step.mAction) { + case CCRunnerAction::None: + break; + + case CCRunnerAction::MinorGC: + JS::MaybeRunNurseryCollection(CycleCollectedJSRuntime::Get()->Runtime(), + step.mParam.mReason); + sScheduler->NoteMinorGCEnd(); + break; + + case CCRunnerAction::ForgetSkippable: + // 'Forget skippable' only, then end this invocation. + FireForgetSkippable(bool(step.mParam.mRemoveChildless), aDeadline); + break; + + case CCRunnerAction::CleanupContentUnbinder: + // Clear content unbinder before the first actual CC slice. + Element::ClearContentUnbinder(); + break; + + case CCRunnerAction::CleanupDeferred: + // and if time still permits, perform deferred deletions. + nsCycleCollector_doDeferredDeletion(); + break; + + case CCRunnerAction::CycleCollect: + // Cycle collection slice. + nsJSContext::RunCycleCollectorSlice(step.mParam.mCCReason, aDeadline); + break; + + case CCRunnerAction::StopRunning: + // End this CC, either because we have run a cycle collection slice, or + // because a CC is no longer needed. + sScheduler->KillCCRunner(); + break; + } + + if (step.mAction != CCRunnerAction::None) { + didDoWork = true; + } + } while (step.mYield == CCRunnerYield::Continue); + + return didDoWork; +} + +// static +bool nsJSContext::HasHadCleanupSinceLastGC() { + return sScheduler->IsEarlyForgetSkippable(1); +} + +// static +void nsJSContext::RunNextCollectorTimer(JS::GCReason aReason, + mozilla::TimeStamp aDeadline) { + sScheduler->RunNextCollectorTimer(aReason, aDeadline); +} + +// static +void nsJSContext::MaybeRunNextCollectorSlice(nsIDocShell* aDocShell, + JS::GCReason aReason) { + if (!aDocShell || !XRE_IsContentProcess()) { + return; + } + + BrowsingContext* bc = aDocShell->GetBrowsingContext(); + if (!bc) { + return; + } + + BrowsingContext* root = bc->Top(); + if (bc == root) { + // We don't want to run collectors when loading the top level page. + return; + } + + nsIDocShell* rootDocShell = root->GetDocShell(); + if (!rootDocShell) { + return; + } + + Document* rootDocument = rootDocShell->GetDocument(); + if (!rootDocument || + rootDocument->GetReadyStateEnum() != Document::READYSTATE_COMPLETE || + rootDocument->IsInBackgroundWindow()) { + return; + } + + PresShell* presShell = rootDocument->GetPresShell(); + if (!presShell) { + return; + } + + nsViewManager* vm = presShell->GetViewManager(); + if (!vm) { + return; + } + + if (!sScheduler->IsUserActive()) { + if (sScheduler->InIncrementalGC() || sScheduler->IsCollectingCycles()) { + Maybe<TimeStamp> next = nsRefreshDriver::GetNextTickHint(); + if (next.isSome()) { + // Try to not delay the next RefreshDriver tick, so give a reasonable + // deadline for collectors. + sScheduler->RunNextCollectorTimer(aReason, next.value()); + } + } else { + nsCOMPtr<nsIDocShell> shell = aDocShell; + NS_DispatchToCurrentThreadQueue( + NS_NewRunnableFunction( + "nsJSContext::MaybeRunNextCollectorSlice", + [shell] { + nsIDocShell::BusyFlags busyFlags = nsIDocShell::BUSY_FLAGS_NONE; + shell->GetBusyFlags(&busyFlags); + if (busyFlags == nsIDocShell::BUSY_FLAGS_NONE) { + return; + } + + // In order to improve performance on the next page, run a minor + // GC. The 16ms limit ensures it isn't called all the time if + // there are for example multiple iframes loading at the same + // time. + JS::RunNurseryCollection( + CycleCollectedJSRuntime::Get()->Runtime(), + JS::GCReason::PREPARE_FOR_PAGELOAD, + mozilla::TimeDuration::FromMilliseconds(16)); + }), + EventQueuePriority::Idle); + } + } +} + +// static +void nsJSContext::PokeGC(JS::GCReason aReason, JSObject* aObj, + TimeDuration aDelay) { + sScheduler->PokeGC(aReason, aObj, aDelay); +} + +// static +void nsJSContext::MaybePokeGC() { + if (sShuttingDown) { + return; + } + + JSRuntime* rt = CycleCollectedJSRuntime::Get()->Runtime(); + JS::GCReason reason = JS::WantEagerMinorGC(rt); + if (reason != JS::GCReason::NO_REASON) { + MOZ_ASSERT(reason == JS::GCReason::EAGER_NURSERY_COLLECTION); + sScheduler->PokeMinorGC(reason); + } + + // Bug 1772638: For now, only do eager minor GCs. Eager major GCs regress some + // benchmarks. Hopefully that will be worked out and this will check for + // whether an eager major GC is needed. +} + +void nsJSContext::DoLowMemoryGC() { + if (sShuttingDown) { + return; + } + nsJSContext::GarbageCollectNow(JS::GCReason::MEM_PRESSURE, + nsJSContext::ShrinkingGC); + nsJSContext::CycleCollectNow(CCReason::MEM_PRESSURE); + if (sScheduler->NeedsGCAfterCC()) { + nsJSContext::GarbageCollectNow(JS::GCReason::MEM_PRESSURE, + nsJSContext::ShrinkingGC); + } +} + +// static +void nsJSContext::LowMemoryGC() { + RefPtr<CCGCScheduler::MayGCPromise> mbPromise = + CCGCScheduler::MayGCNow(JS::GCReason::MEM_PRESSURE); + if (!mbPromise) { + // Normally when the promise is null it means that IPC failed, that probably + // means that something bad happened, don't bother with the GC. + return; + } + mbPromise->Then( + GetMainThreadSerialEventTarget(), __func__, + [](bool aIgnored) { DoLowMemoryGC(); }, + [](mozilla::ipc::ResponseRejectReason r) {}); +} + +// static +void nsJSContext::MaybePokeCC() { + sScheduler->MaybePokeCC(TimeStamp::NowLoRes(), + nsCycleCollector_suspectedCount()); +} + +static void DOMGCSliceCallback(JSContext* aCx, JS::GCProgress aProgress, + const JS::GCDescription& aDesc) { + NS_ASSERTION(NS_IsMainThread(), "GCs must run on the main thread"); + + static TimeStamp sCurrentGCStartTime; + + switch (aProgress) { + case JS::GC_CYCLE_BEGIN: { + // Prevent cycle collections and shrinking during incremental GC. + sScheduler->NoteGCBegin(aDesc.reason_); + sCurrentGCStartTime = TimeStamp::Now(); + break; + } + + case JS::GC_CYCLE_END: { + TimeDuration delta = GetCollectionTimeDelta(); + + if (StaticPrefs::javascript_options_mem_log()) { + nsString gcstats; + gcstats.Adopt(aDesc.formatSummaryMessage(aCx)); + nsAutoString prefix; + nsTextFormatter::ssprintf(prefix, u"GC(T+%.1f)[%s-%i] ", + delta.ToSeconds(), + ProcessNameForCollectorLog(), getpid()); + nsString msg = prefix + gcstats; + nsCOMPtr<nsIConsoleService> cs = + do_GetService(NS_CONSOLESERVICE_CONTRACTID); + if (cs) { + cs->LogStringMessage(msg.get()); + } + } + + sScheduler->NoteGCEnd(); + + // May need to kill the GC runner + sScheduler->KillGCRunner(); + + nsJSContext::MaybePokeCC(); + +#if defined(MOZ_MEMORY) + bool freeDirty = false; +#endif + if (aDesc.isZone_) { + sScheduler->PokeFullGC(); + } else { +#if defined(MOZ_MEMORY) + freeDirty = true; +#endif + sScheduler->SetNeedsFullGC(false); + sScheduler->KillFullGCTimer(); + } + + if (sScheduler->IsCCNeeded(TimeStamp::Now(), + nsCycleCollector_suspectedCount()) != + CCReason::NO_REASON) { +#if defined(MOZ_MEMORY) + // We're likely to free the dirty pages after CC. + freeDirty = false; +#endif + nsCycleCollector_dispatchDeferredDeletion(); + } + + Telemetry::Accumulate(Telemetry::GC_IN_PROGRESS_MS, + TimeUntilNow(sCurrentGCStartTime).ToMilliseconds()); + +#if defined(MOZ_MEMORY) + if (freeDirty && + StaticPrefs:: + dom_memory_foreground_content_processes_have_larger_page_cache()) { + jemalloc_free_dirty_pages(); + } +#endif + break; + } + + case JS::GC_SLICE_BEGIN: + break; + + case JS::GC_SLICE_END: + sScheduler->NoteGCSliceEnd(aDesc.lastSliceStart(aCx), + aDesc.lastSliceEnd(aCx)); + + if (sShuttingDown) { + sScheduler->KillGCRunner(); + } else { + // If incremental GC wasn't triggered by GCTimerFired, we may not have a + // runner to ensure all the slices are handled. So, create the runner + // here. + sScheduler->EnsureOrResetGCRunner(); + } + + if (sScheduler->IsCCNeeded(TimeStamp::Now(), + nsCycleCollector_suspectedCount()) != + CCReason::NO_REASON) { + nsCycleCollector_dispatchDeferredDeletion(); + } + + if (StaticPrefs::javascript_options_mem_log()) { + nsString gcstats; + gcstats.Adopt(aDesc.formatSliceMessage(aCx)); + nsAutoString prefix; + nsTextFormatter::ssprintf(prefix, u"[%s-%i] ", + ProcessNameForCollectorLog(), getpid()); + nsString msg = prefix + gcstats; + nsCOMPtr<nsIConsoleService> cs = + do_GetService(NS_CONSOLESERVICE_CONTRACTID); + if (cs) { + cs->LogStringMessage(msg.get()); + } + } + + break; + + default: + MOZ_CRASH("Unexpected GCProgress value"); + } + + if (sPrevGCSliceCallback) { + (*sPrevGCSliceCallback)(aCx, aProgress, aDesc); + } +} + +void nsJSContext::SetWindowProxy(JS::Handle<JSObject*> aWindowProxy) { + mWindowProxy = aWindowProxy; +} + +JSObject* nsJSContext::GetWindowProxy() { return mWindowProxy; } + +void nsJSContext::LikelyShortLivingObjectCreated() { + ++sScheduler->mLikelyShortLivingObjectsNeedingGC; +} + +void mozilla::dom::StartupJSEnvironment() { + // initialize all our statics, so that we can restart XPCOM + sIsInitialized = false; + sShuttingDown = false; + sCCStats.Init(); +} + +static void SetGCParameter(JSGCParamKey aParam, uint32_t aValue) { + AutoJSAPI jsapi; + jsapi.Init(); + JS_SetGCParameter(jsapi.cx(), aParam, aValue); +} + +static void ResetGCParameter(JSGCParamKey aParam) { + AutoJSAPI jsapi; + jsapi.Init(); + JS_ResetGCParameter(jsapi.cx(), aParam); +} + +static void SetMemoryPrefChangedCallbackMB(const char* aPrefName, + void* aClosure) { + int32_t prefMB = Preferences::GetInt(aPrefName, -1); + // handle overflow and negative pref values + CheckedInt<int32_t> prefB = CheckedInt<int32_t>(prefMB) * 1024 * 1024; + if (prefB.isValid() && prefB.value() >= 0) { + SetGCParameter((JSGCParamKey)(uintptr_t)aClosure, prefB.value()); + } else { + ResetGCParameter((JSGCParamKey)(uintptr_t)aClosure); + } +} + +static void SetMemoryNurseryPrefChangedCallback(const char* aPrefName, + void* aClosure) { + int32_t prefKB = Preferences::GetInt(aPrefName, -1); + // handle overflow and negative pref values + CheckedInt<int32_t> prefB = CheckedInt<int32_t>(prefKB) * 1024; + if (prefB.isValid() && prefB.value() >= 0) { + SetGCParameter((JSGCParamKey)(uintptr_t)aClosure, prefB.value()); + } else { + ResetGCParameter((JSGCParamKey)(uintptr_t)aClosure); + } +} + +static void SetMemoryPrefChangedCallbackInt(const char* aPrefName, + void* aClosure) { + int32_t pref = Preferences::GetInt(aPrefName, -1); + // handle overflow and negative pref values + if (pref >= 0 && pref < 10000) { + SetGCParameter((JSGCParamKey)(uintptr_t)aClosure, pref); + } else { + ResetGCParameter((JSGCParamKey)(uintptr_t)aClosure); + } +} + +static void SetMemoryPrefChangedCallbackBool(const char* aPrefName, + void* aClosure) { + bool pref = Preferences::GetBool(aPrefName); + SetGCParameter((JSGCParamKey)(uintptr_t)aClosure, pref); +} + +static void SetMemoryGCSliceTimePrefChangedCallback(const char* aPrefName, + void* aClosure) { + int32_t pref = Preferences::GetInt(aPrefName, -1); + // handle overflow and negative pref values + if (pref > 0 && pref < 100000) { + sScheduler->SetActiveIntersliceGCBudget( + TimeDuration::FromMilliseconds(pref)); + SetGCParameter(JSGC_SLICE_TIME_BUDGET_MS, pref); + } else { + ResetGCParameter(JSGC_SLICE_TIME_BUDGET_MS); + } +} + +static void SetIncrementalCCPrefChangedCallback(const char* aPrefName, + void* aClosure) { + bool pref = Preferences::GetBool(aPrefName); + sIncrementalCC = pref; +} + +class JSDispatchableRunnable final : public Runnable { + ~JSDispatchableRunnable() { MOZ_ASSERT(!mDispatchable); } + + public: + explicit JSDispatchableRunnable(JS::Dispatchable* aDispatchable) + : mozilla::Runnable("JSDispatchableRunnable"), + mDispatchable(aDispatchable) { + MOZ_ASSERT(mDispatchable); + } + + protected: + NS_IMETHOD Run() override { + MOZ_ASSERT(NS_IsMainThread()); + + AutoJSAPI jsapi; + jsapi.Init(); + + JS::Dispatchable::MaybeShuttingDown maybeShuttingDown = + sShuttingDown ? JS::Dispatchable::ShuttingDown + : JS::Dispatchable::NotShuttingDown; + + mDispatchable->run(jsapi.cx(), maybeShuttingDown); + mDispatchable = nullptr; // mDispatchable may delete itself + + return NS_OK; + } + + private: + JS::Dispatchable* mDispatchable; +}; + +static bool DispatchToEventLoop(void* closure, + JS::Dispatchable* aDispatchable) { + MOZ_ASSERT(!closure); + + // This callback may execute either on the main thread or a random JS-internal + // helper thread. This callback can be called during shutdown so we cannot + // simply NS_DispatchToMainThread. Failure during shutdown is expected and + // properly handled by the JS engine. + + nsCOMPtr<nsIEventTarget> mainTarget = GetMainThreadSerialEventTarget(); + if (!mainTarget) { + return false; + } + + RefPtr<JSDispatchableRunnable> r = new JSDispatchableRunnable(aDispatchable); + MOZ_ALWAYS_SUCCEEDS(mainTarget->Dispatch(r.forget(), NS_DISPATCH_NORMAL)); + return true; +} + +static bool ConsumeStream(JSContext* aCx, JS::Handle<JSObject*> aObj, + JS::MimeType aMimeType, + JS::StreamConsumer* aConsumer) { + return FetchUtil::StreamResponseToJS(aCx, aObj, aMimeType, aConsumer, + nullptr); +} + +static js::SliceBudget CreateGCSliceBudget(JS::GCReason aReason, + int64_t aMillis) { + return sScheduler->CreateGCSliceBudget( + mozilla::TimeDuration::FromMilliseconds(aMillis), false, false); +} + +void nsJSContext::EnsureStatics() { + if (sIsInitialized) { + if (!nsContentUtils::XPConnect()) { + MOZ_CRASH(); + } + return; + } + + // Let's make sure that our main thread is the same as the xpcom main thread. + MOZ_ASSERT(NS_IsMainThread()); + + sScheduler = + new (&sSchedulerStorage) CCGCScheduler(); // Reset the scheduler state. + + AutoJSAPI jsapi; + jsapi.Init(); + + sPrevGCSliceCallback = JS::SetGCSliceCallback(jsapi.cx(), DOMGCSliceCallback); + + JS::SetCreateGCSliceBudgetCallback(jsapi.cx(), CreateGCSliceBudget); + + JS::InitDispatchToEventLoop(jsapi.cx(), DispatchToEventLoop, nullptr); + JS::InitConsumeStreamCallback(jsapi.cx(), ConsumeStream, + FetchUtil::ReportJSStreamError); + + // Set these global xpconnect options... + Preferences::RegisterCallbackAndCall(SetMemoryPrefChangedCallbackMB, + "javascript.options.mem.max", + (void*)JSGC_MAX_BYTES); + Preferences::RegisterCallbackAndCall(SetMemoryNurseryPrefChangedCallback, + "javascript.options.mem.nursery.min_kb", + (void*)JSGC_MIN_NURSERY_BYTES); + Preferences::RegisterCallbackAndCall(SetMemoryNurseryPrefChangedCallback, + "javascript.options.mem.nursery.max_kb", + (void*)JSGC_MAX_NURSERY_BYTES); + + Preferences::RegisterCallbackAndCall(SetMemoryPrefChangedCallbackBool, + "javascript.options.mem.gc_per_zone", + (void*)JSGC_PER_ZONE_GC_ENABLED); + + Preferences::RegisterCallbackAndCall(SetMemoryPrefChangedCallbackBool, + "javascript.options.mem.gc_incremental", + (void*)JSGC_INCREMENTAL_GC_ENABLED); + + Preferences::RegisterCallbackAndCall(SetMemoryPrefChangedCallbackBool, + "javascript.options.mem.gc_compacting", + (void*)JSGC_COMPACTING_ENABLED); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackBool, + "javascript.options.mem.gc_parallel_marking", + (void*)JSGC_PARALLEL_MARKING_ENABLED); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_parallel_marking_threshold_mb", + (void*)JSGC_PARALLEL_MARKING_THRESHOLD_MB); + + Preferences::RegisterCallbackAndCall( + SetMemoryGCSliceTimePrefChangedCallback, + "javascript.options.mem.gc_incremental_slice_ms"); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackBool, + "javascript.options.mem.incremental_weakmap", + (void*)JSGC_INCREMENTAL_WEAKMAP_ENABLED); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_high_frequency_time_limit_ms", + (void*)JSGC_HIGH_FREQUENCY_TIME_LIMIT); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_low_frequency_heap_growth", + (void*)JSGC_LOW_FREQUENCY_HEAP_GROWTH); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_high_frequency_large_heap_growth", + (void*)JSGC_HIGH_FREQUENCY_LARGE_HEAP_GROWTH); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_high_frequency_small_heap_growth", + (void*)JSGC_HIGH_FREQUENCY_SMALL_HEAP_GROWTH); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackBool, + "javascript.options.mem.gc_balanced_heap_limits", + (void*)JSGC_BALANCED_HEAP_LIMITS_ENABLED); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_heap_growth_factor", + (void*)JSGC_HEAP_GROWTH_FACTOR); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_small_heap_size_max_mb", + (void*)JSGC_SMALL_HEAP_SIZE_MAX); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_large_heap_size_min_mb", + (void*)JSGC_LARGE_HEAP_SIZE_MIN); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_allocation_threshold_mb", + (void*)JSGC_ALLOCATION_THRESHOLD); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_malloc_threshold_base_mb", + (void*)JSGC_MALLOC_THRESHOLD_BASE); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_small_heap_incremental_limit", + (void*)JSGC_SMALL_HEAP_INCREMENTAL_LIMIT); + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_large_heap_incremental_limit", + (void*)JSGC_LARGE_HEAP_INCREMENTAL_LIMIT); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_urgent_threshold_mb", + (void*)JSGC_URGENT_THRESHOLD_MB); + + Preferences::RegisterCallbackAndCall(SetIncrementalCCPrefChangedCallback, + "dom.cycle_collector.incremental"); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_min_empty_chunk_count", + (void*)JSGC_MIN_EMPTY_CHUNK_COUNT); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_max_empty_chunk_count", + (void*)JSGC_MAX_EMPTY_CHUNK_COUNT); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_helper_thread_ratio", + (void*)JSGC_HELPER_THREAD_RATIO); + + Preferences::RegisterCallbackAndCall( + SetMemoryPrefChangedCallbackInt, + "javascript.options.mem.gc_max_helper_threads", + (void*)JSGC_MAX_HELPER_THREADS); + + nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService(); + if (!obs) { + MOZ_CRASH(); + } + + nsIObserver* observer = new nsJSEnvironmentObserver(); + obs->AddObserver(observer, "memory-pressure", false); + obs->AddObserver(observer, "user-interaction-inactive", false); + obs->AddObserver(observer, "user-interaction-active", false); + obs->AddObserver(observer, "quit-application", false); + obs->AddObserver(observer, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false); + obs->AddObserver(observer, "content-child-will-shutdown", false); + + sIsInitialized = true; +} + +void mozilla::dom::ShutdownJSEnvironment() { + sShuttingDown = true; + sScheduler->Shutdown(); +} + +AsyncErrorReporter::AsyncErrorReporter(xpc::ErrorReport* aReport) + : Runnable("dom::AsyncErrorReporter"), mReport(aReport) {} + +void AsyncErrorReporter::SerializeStack(JSContext* aCx, + JS::Handle<JSObject*> aStack) { + mStackHolder = MakeUnique<SerializedStackHolder>(); + mStackHolder->SerializeMainThreadOrWorkletStack(aCx, aStack); +} + +void AsyncErrorReporter::SetException(JSContext* aCx, + JS::Handle<JS::Value> aException) { + MOZ_ASSERT(NS_IsMainThread()); + mException.init(aCx, aException); + mHasException = true; +} + +NS_IMETHODIMP AsyncErrorReporter::Run() { + AutoJSAPI jsapi; + // We're only using this context to deserialize a stack to report to the + // console, so the scope we use doesn't matter. Stack frame filtering happens + // based on the principal encoded into the frame and the caller compartment, + // not the compartment of the frame object, and the console reporting code + // will not be using our context, and therefore will not care what compartment + // it has entered. + DebugOnly<bool> ok = jsapi.Init(xpc::PrivilegedJunkScope()); + MOZ_ASSERT(ok, "Problem with system global?"); + JSContext* cx = jsapi.cx(); + JS::Rooted<JSObject*> stack(cx); + JS::Rooted<JSObject*> stackGlobal(cx); + if (mStackHolder) { + stack = mStackHolder->ReadStack(cx); + if (stack) { + stackGlobal = JS::CurrentGlobalOrNull(cx); + } + } + + JS::Rooted<Maybe<JS::Value>> exception(cx, Nothing()); + if (mHasException) { + MOZ_ASSERT(NS_IsMainThread()); + exception = Some(mException); + // Remove our reference to the exception. + mException.setUndefined(); + mHasException = false; + } + + mReport->LogToConsoleWithStack(nullptr, exception, stack, stackGlobal); + return NS_OK; +} + +// A fast-array class for JS. This class supports both nsIJSScriptArray and +// nsIArray. If it is JS itself providing and consuming this class, all work +// can be done via nsIJSScriptArray, and avoid the conversion of elements +// to/from nsISupports. +// When consumed by non-JS (eg, another script language), conversion is done +// on-the-fly. +class nsJSArgArray final : public nsIJSArgArray { + public: + nsJSArgArray(JSContext* aContext, uint32_t argc, const JS::Value* argv, + nsresult* prv); + + // nsISupports + NS_DECL_CYCLE_COLLECTING_ISUPPORTS + NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_AMBIGUOUS(nsJSArgArray, + nsIJSArgArray) + + // nsIArray + NS_DECL_NSIARRAY + + // nsIJSArgArray + nsresult GetArgs(uint32_t* argc, void** argv) override; + + void ReleaseJSObjects(); + + protected: + ~nsJSArgArray(); + JSContext* mContext; + JS::Heap<JS::Value>* mArgv; + uint32_t mArgc; +}; + +nsJSArgArray::nsJSArgArray(JSContext* aContext, uint32_t argc, + const JS::Value* argv, nsresult* prv) + : mContext(aContext), mArgv(nullptr), mArgc(argc) { + // copy the array - we don't know its lifetime, and ours is tied to xpcom + // refcounting. + if (argc) { + mArgv = new (fallible) JS::Heap<JS::Value>[argc]; + if (!mArgv) { + *prv = NS_ERROR_OUT_OF_MEMORY; + return; + } + } + + // Callers are allowed to pass in a null argv even for argc > 0. They can + // then use GetArgs to initialize the values. + if (argv) { + for (uint32_t i = 0; i < argc; ++i) mArgv[i] = argv[i]; + } + + if (argc > 0) { + mozilla::HoldJSObjects(this); + } + + *prv = NS_OK; +} + +nsJSArgArray::~nsJSArgArray() { ReleaseJSObjects(); } + +void nsJSArgArray::ReleaseJSObjects() { + delete[] mArgv; + + if (mArgc > 0) { + mArgc = 0; + mozilla::DropJSObjects(this); + } +} + +// QueryInterface implementation for nsJSArgArray +NS_IMPL_CYCLE_COLLECTION_CLASS(nsJSArgArray) + +NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsJSArgArray) + tmp->ReleaseJSObjects(); +NS_IMPL_CYCLE_COLLECTION_UNLINK_END +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsJSArgArray) +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END + +NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsJSArgArray) + if (tmp->mArgv) { + for (uint32_t i = 0; i < tmp->mArgc; ++i) { + NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mArgv[i]) + } + } +NS_IMPL_CYCLE_COLLECTION_TRACE_END + +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsJSArgArray) + NS_INTERFACE_MAP_ENTRY(nsIArray) + NS_INTERFACE_MAP_ENTRY(nsIJSArgArray) + NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIJSArgArray) +NS_INTERFACE_MAP_END + +NS_IMPL_CYCLE_COLLECTING_ADDREF(nsJSArgArray) +NS_IMPL_CYCLE_COLLECTING_RELEASE(nsJSArgArray) + +nsresult nsJSArgArray::GetArgs(uint32_t* argc, void** argv) { + *argv = (void*)mArgv; + *argc = mArgc; + return NS_OK; +} + +// nsIArray impl +NS_IMETHODIMP nsJSArgArray::GetLength(uint32_t* aLength) { + *aLength = mArgc; + return NS_OK; +} + +NS_IMETHODIMP nsJSArgArray::QueryElementAt(uint32_t index, const nsIID& uuid, + void** result) { + *result = nullptr; + if (index >= mArgc) return NS_ERROR_INVALID_ARG; + + if (uuid.Equals(NS_GET_IID(nsIVariant)) || + uuid.Equals(NS_GET_IID(nsISupports))) { + // Have to copy a Heap into a Rooted to work with it. + JS::Rooted<JS::Value> val(mContext, mArgv[index]); + return nsContentUtils::XPConnect()->JSToVariant(mContext, val, + (nsIVariant**)result); + } + NS_WARNING("nsJSArgArray only handles nsIVariant"); + return NS_ERROR_NO_INTERFACE; +} + +NS_IMETHODIMP nsJSArgArray::IndexOf(uint32_t startIndex, nsISupports* element, + uint32_t* _retval) { + return NS_ERROR_NOT_IMPLEMENTED; +} + +NS_IMETHODIMP nsJSArgArray::ScriptedEnumerate(const nsIID& aElemIID, + uint8_t aArgc, + nsISimpleEnumerator** aResult) { + return NS_ERROR_NOT_IMPLEMENTED; +} + +NS_IMETHODIMP nsJSArgArray::EnumerateImpl(const nsID& aEntryIID, + nsISimpleEnumerator** _retval) { + return NS_ERROR_NOT_IMPLEMENTED; +} + +// The factory function +nsresult NS_CreateJSArgv(JSContext* aContext, uint32_t argc, + const JS::Value* argv, nsIJSArgArray** aArray) { + nsresult rv; + nsCOMPtr<nsIJSArgArray> ret = new nsJSArgArray(aContext, argc, argv, &rv); + if (NS_FAILED(rv)) { + return rv; + } + ret.forget(aArray); + return NS_OK; +} |