wuggy/Dactyloidae
wuggy/Dactyloidae
1
0
Fork 0
mirror of https://repo.dactyloidae.xyz/Dactyloidae/UXP.git synced 2026-09-03 22:38:41 +09:00
Code Issues Projects Releases Packages Wiki Activity

Improve dead compartment collection js/src

Browse source
This commit is contained in:
win7-7 2019-04-29 11:59:46 +03:00 • committed by Roy Tam
commit a695e349d8
3 changed files with 141 additions and 91 deletions
Download patch file Download diff file Expand all files Collapse all files

198
js/src/jsgc.cpp
View file

@ -1524,20 +1524,11 @@ GCMarker::delayMarkingChildren(const void* thing)
}
inline void
ArenaLists::prepareForIncrementalGC(JSRuntime* rt)
ArenaLists::prepareForIncrementalGC()
{
for (auto i : AllAllocKinds()) {
FreeSpan* span = freeLists[i];
if (span != &placeholder) {
if (!span->isEmpty()) {
Arena* arena = span->getArena();
arena->allocatedDuringIncremental = true;
rt->gc.marker.delayMarkingArena(arena);
} else {
freeLists[i] = &placeholder;
}
}
}
purge();
for (auto i : AllAllocKinds())
arenaLists[i].moveCursorToEnd();
}
/* Compacting GC */
@ -2251,7 +2242,7 @@ GCRuntime::updateTypeDescrObjects(MovingTracer* trc, Zone* zone)
{
zone->typeDescrObjects.sweep();
for (auto r = zone->typeDescrObjects.all(); !r.empty(); r.popFront())
UpdateCellPointers(trc, r.front().get());
UpdateCellPointers(trc, r.front());
}
void
@ -3579,6 +3570,23 @@ RelazifyFunctions(Zone* zone, AllocKind kind)
}
}
static bool
ShouldCollectZone(Zone* zone, JS::gcreason::Reason reason)
{
// Normally we collect all scheduled zones.
if (reason != JS::gcreason::COMPARTMENT_REVIVED)
return zone->isGCScheduled();
// If we are repeating a GC becuase we noticed dead compartments haven't
// been collected, then only collect zones contianing those compartments.
for (CompartmentsInZoneIter comp(zone); !comp.done(); comp.next()) {
if (comp->scheduledForDestruction)
return true;
}
return false;
}
bool
GCRuntime::beginMarkPhase(JS::gcreason::Reason reason, AutoLockForExclusiveAccess& lock)
{
@ -3602,7 +3610,7 @@ GCRuntime::beginMarkPhase(JS::gcreason::Reason reason, AutoLockForExclusiveAcces
#endif
/* Set up which zones will be collected. */
if (zone->isGCScheduled()) {
if (ShouldCollectZone(zone, reason)) {
if (!zone->isAtomsZone()) {
any = true;
zone->setGCState(Zone::Mark);
@ -3621,7 +3629,7 @@ GCRuntime::beginMarkPhase(JS::gcreason::Reason reason, AutoLockForExclusiveAcces
for (CompartmentsIter c(rt, WithAtoms); !c.done(); c.next()) {
c->marked = false;
c->scheduledForDestruction = false;
c->maybeAlive = false;
c->maybeAlive = c->hasBeenEntered() || !c->zone()->isGCScheduled();
if (shouldPreserveJITCode(c, currentTime, reason, canAllocateMoreCode))
c->zone()->setPreservingCode(true);
}
@ -3640,6 +3648,12 @@ GCRuntime::beginMarkPhase(JS::gcreason::Reason reason, AutoLockForExclusiveAcces
* keepAtoms() will only change on the main thread, which we are currently
* on. If the value of keepAtoms() changes between GC slices, then we'll
* cancel the incremental GC. See IsIncrementalGCSafe.
*/
if (isFull && !rt->keepAtoms()) {
Zone* atomsZone = rt->atomsCompartment(lock)->zone();
@ -3655,15 +3669,12 @@ GCRuntime::beginMarkPhase(JS::gcreason::Reason reason, AutoLockForExclusiveAcces
return false;
/*
* At the end of each incremental slice, we call prepareForIncrementalGC,
* which marks objects in all arenas that we're currently allocating
* into. This can cause leaks if unreachable objects are in these
* arenas. This purge call ensures that we only mark arenas that have had
* allocations after the incremental GC started.
* Ensure that after the start of a collection we don't allocate into any
* existing arenas, as this can cause unreachable things to be marked.
*/
if (isIncremental) {
for (GCZonesIter zone(rt); !zone.done(); zone.next())
zone->arenas.purge();
zone->arenas.prepareForIncrementalGC();
}
MemProfiler::MarkTenuredStart(rt);
@ -3747,13 +3758,11 @@ GCRuntime::beginMarkPhase(JS::gcreason::Reason reason, AutoLockForExclusiveAcces
gcstats::AutoPhase ap2(stats, gcstats::PHASE_MARK_ROOTS);
if (isIncremental) {
gcstats::AutoPhase ap3(stats, gcstats::PHASE_BUFFER_GRAY_ROOTS);
bufferGrayRoots();
}
markCompartments();
if (isIncremental) {
bufferGrayRoots();
markCompartments();
}
return true;
}
@ -3766,9 +3775,14 @@ GCRuntime::markCompartments()
* This code ensures that if a compartment is "dead", then it will be
* collected in this GC. A compartment is considered dead if its maybeAlive
* flag is false. The maybeAlive flag is set if:
* (1) the compartment has incoming cross-compartment edges, or
* (2) an object in the compartment was marked during root marking, either
* as a black root or a gray root.
* (1) the compartment has been entered (set in beginMarkPhase() above)
* (2) the compartment is not being collected (set in beginMarkPhase()
* above)
* (3) an object in the compartment was marked during root marking, either
* as a black root or a gray root (set in RootMarking.cpp), or
* (4) the compartment has incoming cross-compartment edges from another
* compartment that has maybeAlive set (set by this method).
*
* If the maybeAlive is false, then we set the scheduledForDestruction flag.
* At the end of the GC, we look for compartments where
* scheduledForDestruction is true. These are compartments that were somehow
@ -3786,26 +3800,37 @@ GCRuntime::markCompartments()
* allocation and read barriers during JS_TransplantObject and the like.
*/
/* Set the maybeAlive flag based on cross-compartment edges. */
for (CompartmentsIter c(rt, SkipAtoms); !c.done(); c.next()) {
for (JSCompartment::WrapperEnum e(c); !e.empty(); e.popFront()) {
/* Propagate the maybeAlive flag via cross-compartment edges. */
Vector<JSCompartment*, 0, js::SystemAllocPolicy> workList;
for (CompartmentsIter comp(rt, SkipAtoms); !comp.done(); comp.next()) {
if (comp->maybeAlive) {
if (!workList.append(comp))
return;
}
}
while (!workList.empty()) {
JSCompartment* comp = workList.popCopy();
for (JSCompartment::WrapperEnum e(comp); !e.empty(); e.popFront()) {
if (e.front().key().is<JSString*>())
continue;
JSCompartment* dest = e.front().mutableKey().compartment();
if (dest)
if (dest && !dest->maybeAlive) {
dest->maybeAlive = true;
if (!workList.append(dest))
return;
}
}
}
/*
* For black roots, code in gc/Marking.cpp will already have set maybeAlive
* during MarkRuntime.
*/
/* Propogate maybeAlive to scheduleForDestruction. */
for (GCCompartmentsIter c(rt); !c.done(); c.next()) {
if (!c->maybeAlive && !rt->isAtomsCompartment(c))
c->scheduledForDestruction = true;
/* Set scheduleForDestruction based on maybeAlive. */
for (GCCompartmentsIter comp(rt); !comp.done(); comp.next()) {
MOZ_ASSERT(!comp->scheduledForDestruction);
if (!comp->maybeAlive && !rt->isAtomsCompartment(comp))
comp->scheduledForDestruction = true;
}
}
@ -5306,7 +5331,7 @@ AutoGCSlice::~AutoGCSlice()
for (ZonesIter zone(runtime, WithAtoms); !zone.done(); zone.next()) {
if (zone->isGCMarking()) {
zone->setNeedsIncrementalBarrier(true, Zone::UpdateJit);
zone->arenas.prepareForIncrementalGC(runtime);
zone->arenas.purge();
} else {
zone->setNeedsIncrementalBarrier(false, Zone::UpdateJit);
}
@ -5487,9 +5512,9 @@ gc::AbortReason
gc::IsIncrementalGCUnsafe(JSRuntime* rt)
{
MOZ_ASSERT(!rt->mainThread.suppressGC);
if (rt->keepAtoms())
return gc::AbortReason::KeepAtomsSet;
if (rt->keepAtoms())
return gc::AbortReason::KeepAtomsSet;
if (!rt->gc.isIncrementalGCAllowed())
return gc::AbortReason::IncrementalDisabled;
@ -5498,9 +5523,17 @@ gc::IsIncrementalGCUnsafe(JSRuntime* rt)
}
void
GCRuntime::budgetIncrementalGC(SliceBudget& budget, AutoLockForExclusiveAccess& lock)
GCRuntime::budgetIncrementalGC(JS::gcreason::Reason reason, SliceBudget& budget,
AutoLockForExclusiveAccess& lock)
{
AbortReason unsafeReason = IsIncrementalGCUnsafe(rt);
if (unsafeReason == AbortReason::None) {
if (reason == JS::gcreason::COMPARTMENT_REVIVED)
unsafeReason = gc::AbortReason::CompartmentRevived;
else if (mode != JSGC_MODE_INCREMENTAL)
unsafeReason = gc::AbortReason::ModeChange;
}
if (unsafeReason != AbortReason::None) {
resetIncrementalGC(unsafeReason, lock);
budget.makeUnlimited();
@ -5508,12 +5541,7 @@ GCRuntime::budgetIncrementalGC(SliceBudget& budget, AutoLockForExclusiveAccess&
return;
}
if (mode != JSGC_MODE_INCREMENTAL) {
resetIncrementalGC(AbortReason::ModeChange, lock);
budget.makeUnlimited();
stats.nonincremental(AbortReason::ModeChange);
return;
}
if (isTooMuchMalloc()) {
budget.makeUnlimited();
@ -5660,6 +5688,10 @@ GCRuntime::gcCycle(bool nonincrementalByAPI, SliceBudget& budget, JS::gcreason::
}
State prevState = incrementalState;
if (nonincrementalByAPI) {
// Reset any in progress incremental GC if this was triggered via the
@ -5672,7 +5704,7 @@ GCRuntime::gcCycle(bool nonincrementalByAPI, SliceBudget& budget, JS::gcreason::
stats.nonincremental(gc::AbortReason::NonIncrementalRequested);
budget.makeUnlimited();
} else {
budgetIncrementalGC(budget, session.lock);
budgetIncrementalGC(reason, budget, session.lock);
}
/* The GC was reset, so we need a do-over. */
@ -5764,6 +5796,22 @@ GCRuntime::checkIfGCAllowedInCurrentState(JS::gcreason::Reason reason)
return true;
}
bool
GCRuntime::shouldRepeatForDeadZone(JS::gcreason::Reason reason)
{
MOZ_ASSERT_IF(reason == JS::gcreason::COMPARTMENT_REVIVED, !isIncremental);
if (!isIncremental || isIncrementalGCInProgress())
return false;
for (CompartmentsIter c(rt, SkipAtoms); !c.done(); c.next()) {
if (c->scheduledForDestruction)
return true;
}
return false;
}
void
GCRuntime::collect(bool nonincrementalByAPI, SliceBudget budget, JS::gcreason::Reason reason)
{
@ -5782,27 +5830,23 @@ GCRuntime::collect(bool nonincrementalByAPI, SliceBudget budget, JS::gcreason::R
do {
poked = false;
bool wasReset = gcCycle(nonincrementalByAPI, budget, reason);
/* Need to re-schedule all zones for GC. */
if (poked && cleanUpEverything)
bool repeatForDeadZone = false;
if (poked && cleanUpEverything) {
/* Need to re-schedule all zones for GC. */
JS::PrepareForFullGC(rt->contextFromMainThread());
/*
* This code makes an extra effort to collect compartments that we
* thought were dead at the start of the GC. See the large comment in
* beginMarkPhase.
*/
bool repeatForDeadZone = false;
if (!nonincrementalByAPI && !isIncrementalGCInProgress()) {
for (CompartmentsIter c(rt, SkipAtoms); !c.done(); c.next()) {
if (c->scheduledForDestruction) {
nonincrementalByAPI = true;
repeatForDeadZone = true;
reason = JS::gcreason::COMPARTMENT_REVIVED;
c->zone()->scheduleGC();
}
}
}
} else if (shouldRepeatForDeadZone(reason) && !wasReset) {
/*
* This code makes an extra effort to collect compartments that we
* thought were dead at the start of the GC. See the large comment
* in beginMarkPhase.
*/
repeatForDeadZone = true;
reason = JS::gcreason::COMPARTMENT_REVIVED;
}
/*
* If we reset an existing GC, we need to start a new one. Also, we
@ -7070,4 +7114,4 @@ js::gc::detail::CellIsMarkedGrayIfKnown(const Cell* cell)
}
return detail::CellIsMarkedGray(tc);
}
}