Source code
Revision control
Copy as Markdown
Other Tools
/* -*- 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
#include "debugger/DebuggerMemory.h"
#include "mozilla/Maybe.h"
#include "mozilla/Vector.h"
#include <stdlib.h>
#include <utility>
#include "jsapi.h"
#include "builtin/MapObject.h"
#include "debugger/Debugger.h"
#include "gc/Marking.h"
#include "js/AllocPolicy.h"
#include "js/Debug.h"
#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_*
#include "js/PropertySpec.h"
#include "js/TracingAPI.h"
#include "js/UbiNode.h"
#include "js/UbiNodeCensus.h"
#include "js/Utility.h"
#include "vm/GlobalObject.h"
#include "vm/JSContext.h"
#include "vm/PlainObject.h" // js::PlainObject
#include "vm/Realm.h"
#include "vm/SavedStacks.h"
#include "debugger/Debugger-inl.h"
#include "gc/StableCellHasher-inl.h"
#include "vm/NativeObject-inl.h"
using namespace js;
/* static */
DebuggerMemory* DebuggerMemory::create(JSContext* cx, Debugger* dbg) {
Value memoryProtoValue =
dbg->object->getReservedSlot(Debugger::JSSLOT_DEBUG_MEMORY_PROTO);
RootedObject memoryProto(cx, &memoryProtoValue.toObject());
Rooted<DebuggerMemory*> memory(
cx, NewObjectWithGivenProto<DebuggerMemory>(cx, memoryProto));
if (!memory) {
return nullptr;
}
dbg->object->setReservedSlot(Debugger::JSSLOT_DEBUG_MEMORY_INSTANCE,
ObjectValue(*memory));
memory->setReservedSlot(JSSLOT_DEBUGGER, ObjectValue(*dbg->object));
return memory;
}
Debugger* DebuggerMemory::getDebugger() {
const Value& dbgVal = getReservedSlot(JSSLOT_DEBUGGER);
return Debugger::fromJSObject(&dbgVal.toObject());
}
/* static */
bool DebuggerMemory::construct(JSContext* cx, unsigned argc, Value* vp) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_NO_CONSTRUCTOR,
"Debugger.Source");
return false;
}
/* static */ const JSClass DebuggerMemory::class_ = {
"Memory",
JSCLASS_HAS_RESERVED_SLOTS(JSSLOT_COUNT),
};
/* static */
DebuggerMemory* DebuggerMemory::checkThis(JSContext* cx, CallArgs& args) {
const Value& thisValue = args.thisv();
if (!thisValue.isObject()) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_OBJECT_REQUIRED,
InformalValueTypeName(thisValue));
return nullptr;
}
JSObject& thisObject = thisValue.toObject();
if (!thisObject.is<DebuggerMemory>()) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_INCOMPATIBLE_PROTO, class_.name, "method",
thisObject.getClass()->name);
return nullptr;
}
return &thisObject.as<DebuggerMemory>();
}
struct MOZ_STACK_CLASS DebuggerMemory::CallData {
JSContext* cx;
const CallArgs& args;
Handle<DebuggerMemory*> memory;
CallData(JSContext* cx, const CallArgs& args, Handle<DebuggerMemory*> memory)
: cx(cx), args(args), memory(memory) {}
// Accessor properties of Debugger.Memory.prototype.
bool setTrackingAllocationSites();
bool getTrackingAllocationSites();
bool setMaxAllocationsLogLength();
bool getMaxAllocationsLogLength();
bool setAllocationSamplingProbability();
bool getAllocationSamplingProbability();
bool getAllocationsLogOverflowed();
bool getOnGarbageCollection();
bool setOnGarbageCollection();
// Function properties of Debugger.Memory.prototype.
bool takeCensus();
bool drainAllocationsLog();
using Method = bool (CallData::*)();
template <Method MyMethod>
static bool ToNative(JSContext* cx, unsigned argc, Value* vp);
};
template <DebuggerMemory::CallData::Method MyMethod>
/* static */
bool DebuggerMemory::CallData::ToNative(JSContext* cx, unsigned argc,
Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
Rooted<DebuggerMemory*> memory(cx, DebuggerMemory::checkThis(cx, args));
if (!memory) {
return false;
}
CallData data(cx, args, memory);
return (data.*MyMethod)();
}
static bool undefined(const CallArgs& args) {
args.rval().setUndefined();
return true;
}
bool DebuggerMemory::CallData::setTrackingAllocationSites() {
if (!args.requireAtLeast(cx, "(set trackingAllocationSites)", 1)) {
return false;
}
Debugger* dbg = memory->getDebugger();
bool enabling = ToBoolean(args[0]);
if (enabling == dbg->trackingAllocationSites) {
return undefined(args);
}
dbg->trackingAllocationSites = enabling;
if (enabling) {
if (!dbg->addAllocationsTrackingForAllDebuggees(cx)) {
dbg->trackingAllocationSites = false;
return false;
}
} else {
dbg->removeAllocationsTrackingForAllDebuggees();
}
return undefined(args);
}
bool DebuggerMemory::CallData::getTrackingAllocationSites() {
args.rval().setBoolean(memory->getDebugger()->trackingAllocationSites);
return true;
}
bool DebuggerMemory::CallData::drainAllocationsLog() {
Debugger* dbg = memory->getDebugger();
if (!dbg->trackingAllocationSites) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_NOT_TRACKING_ALLOCATIONS,
"drainAllocationsLog");
return false;
}
size_t length = dbg->allocationsLog.length();
Rooted<ArrayObject*> result(cx, NewDenseFullyAllocatedArray(cx, length));
if (!result) {
return false;
}
result->ensureDenseInitializedLength(0, length);
for (size_t i = 0; i < length; i++) {
Rooted<PlainObject*> obj(cx, NewPlainObject(cx));
if (!obj) {
return false;
}
// Don't pop the AllocationsLogEntry yet. The queue's links are followed
// by the GC to find the AllocationsLogEntry, but are not barriered, so
// we must edit them with great care. Use the queue entry in place, and
// then pop and delete together.
Debugger::AllocationsLogEntry& entry = dbg->allocationsLog.front();
RootedValue frame(cx, ObjectOrNullValue(entry.frame));
if (!DefineDataProperty(cx, obj, cx->names().frame, frame)) {
return false;
}
double when =
(entry.when - mozilla::TimeStamp::ProcessCreation()).ToMilliseconds();
RootedValue timestampValue(cx, NumberValue(when));
if (!DefineDataProperty(cx, obj, cx->names().timestamp, timestampValue)) {
return false;
}
RootedString className(
cx, Atomize(cx, entry.className, strlen(entry.className)));
if (!className) {
return false;
}
RootedValue classNameValue(cx, StringValue(className));
if (!DefineDataProperty(cx, obj, cx->names().class_, classNameValue)) {
return false;
}
RootedValue size(cx, NumberValue(entry.size));
if (!DefineDataProperty(cx, obj, cx->names().size, size)) {
return false;
}
RootedValue inNursery(cx, BooleanValue(entry.inNursery));
if (!DefineDataProperty(cx, obj, cx->names().inNursery, inNursery)) {
return false;
}
result->setDenseElement(i, ObjectValue(*obj));
// Pop the front queue entry, and delete it immediately, so that the GC
// sees the AllocationsLogEntry's HeapPtr barriers run atomically with
// the change to the graph (the queue link).
dbg->allocationsLog.popFront();
}
dbg->allocationsLogOverflowed = false;
args.rval().setObject(*result);
return true;
}
bool DebuggerMemory::CallData::getMaxAllocationsLogLength() {
args.rval().setInt32(memory->getDebugger()->maxAllocationsLogLength);
return true;
}
bool DebuggerMemory::CallData::setMaxAllocationsLogLength() {
if (!args.requireAtLeast(cx, "(set maxAllocationsLogLength)", 1)) {
return false;
}
int32_t max;
if (!ToInt32(cx, args[0], &max)) {
return false;
}
if (max < 1) {
JS_ReportErrorNumberASCII(
cx, GetErrorMessage, nullptr, JSMSG_UNEXPECTED_TYPE,
"(set maxAllocationsLogLength)'s parameter", "not a positive integer");
return false;
}
Debugger* dbg = memory->getDebugger();
dbg->maxAllocationsLogLength = max;
while (dbg->allocationsLog.length() > dbg->maxAllocationsLogLength) {
dbg->allocationsLog.popFront();
}
args.rval().setUndefined();
return true;
}
bool DebuggerMemory::CallData::getAllocationSamplingProbability() {
args.rval().setDouble(memory->getDebugger()->allocationSamplingProbability);
return true;
}
bool DebuggerMemory::CallData::setAllocationSamplingProbability() {
if (!args.requireAtLeast(cx, "(set allocationSamplingProbability)", 1)) {
return false;
}
double probability;
if (!ToNumber(cx, args[0], &probability)) {
return false;
}
// Careful! This must also reject NaN.
if (!(0.0 <= probability && probability <= 1.0)) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_UNEXPECTED_TYPE,
"(set allocationSamplingProbability)'s parameter",
"not a number between 0 and 1");
return false;
}
Debugger* dbg = memory->getDebugger();
if (dbg->allocationSamplingProbability != probability) {
dbg->allocationSamplingProbability = probability;
// If this is a change any debuggees would observe, have all debuggee
// realms recompute their sampling probabilities.
if (dbg->trackingAllocationSites) {
for (auto r = dbg->debuggees.all(); !r.empty(); r.popFront()) {
r.front()->realm()->chooseAllocationSamplingProbability();
}
}
}
args.rval().setUndefined();
return true;
}
bool DebuggerMemory::CallData::getAllocationsLogOverflowed() {
args.rval().setBoolean(memory->getDebugger()->allocationsLogOverflowed);
return true;
}
bool DebuggerMemory::CallData::getOnGarbageCollection() {
return Debugger::getGarbageCollectionHook(cx, args, *memory->getDebugger());
}
bool DebuggerMemory::CallData::setOnGarbageCollection() {
return Debugger::setGarbageCollectionHook(cx, args, *memory->getDebugger());
}
/* Debugger.Memory.prototype.takeCensus */
JS_PUBLIC_API void JS::dbg::SetDebuggerMallocSizeOf(
JSContext* cx, mozilla::MallocSizeOf mallocSizeOf) {
cx->runtime()->debuggerMallocSizeOf = mallocSizeOf;
}
JS_PUBLIC_API mozilla::MallocSizeOf JS::dbg::GetDebuggerMallocSizeOf(
JSContext* cx) {
return cx->runtime()->debuggerMallocSizeOf;
}
using JS::ubi::Census;
using JS::ubi::CountBasePtr;
using JS::ubi::CountTypePtr;
// The takeCensus function works in three phases:
//
// 1) We examine the 'breakdown' property of our 'options' argument, and
// use that to build a CountType tree.
//
// 2) We create a count node for the root of our CountType tree, and then walk
// the heap, counting each node we find, expanding our tree of counts as we
// go.
//
// 3) We walk the tree of counts and produce JavaScript objects reporting the
// accumulated results.
bool DebuggerMemory::CallData::takeCensus() {
Census census(cx);
CountTypePtr rootType;
RootedObject options(cx);
if (args.get(0).isObject()) {
options = &args[0].toObject();
}
if (!JS::ubi::ParseCensusOptions(cx, census, options, rootType)) {
return false;
}
JS::ubi::RootedCount rootCount(cx, rootType->makeCount());
if (!rootCount) {
ReportOutOfMemory(cx);
return false;
}
JS::ubi::CensusHandler handler(census, rootCount,
cx->runtime()->debuggerMallocSizeOf);
Debugger* dbg = memory->getDebugger();
RootedObject dbgObj(cx, dbg->object);
// Populate our target set of debuggee zones.
for (WeakGlobalObjectSet::Range r = dbg->allDebuggees(); !r.empty();
r.popFront()) {
if (!census.targetZones.put(r.front()->zone())) {
ReportOutOfMemory(cx);
return false;
}
}
{
JS::ubi::RootList rootList(cx);
auto [ok, nogc] = rootList.init(dbgObj);
if (!ok) {
ReportOutOfMemory(cx);
return false;
}
JS::ubi::CensusTraversal traversal(cx, handler, nogc);
traversal.wantNames = false;
if (!traversal.addStart(JS::ubi::Node(&rootList)) ||
!traversal.traverse()) {
ReportOutOfMemory(cx);
return false;
}
}
return handler.report(cx, args.rval());
}
/* Debugger.Memory property and method tables. */
/* static */ const JSPropertySpec DebuggerMemory::properties[] = {
JS_DEBUG_PSGS("trackingAllocationSites", getTrackingAllocationSites,
setTrackingAllocationSites),
JS_DEBUG_PSGS("maxAllocationsLogLength", getMaxAllocationsLogLength,
setMaxAllocationsLogLength),
JS_DEBUG_PSGS("allocationSamplingProbability",
getAllocationSamplingProbability,
setAllocationSamplingProbability),
JS_DEBUG_PSG("allocationsLogOverflowed", getAllocationsLogOverflowed),
JS_DEBUG_PSGS("onGarbageCollection", getOnGarbageCollection,
setOnGarbageCollection),
JS_PS_END,
};
/* static */ const JSFunctionSpec DebuggerMemory::methods[] = {
JS_DEBUG_FN("drainAllocationsLog", drainAllocationsLog, 0),
JS_DEBUG_FN("takeCensus", takeCensus, 0),
JS_FS_END,
};