Revision: 9251
Author: [email protected]
Date: Tue Sep 13 02:24:38 2011
Log: Guard against rare case of allocation failure during evacuation.
This fixes flakiness of mjsunit/regress/regress-524 (crash always
reproducible with --always-compact).
[email protected]
BUG=v8:1556
Review URL: http://codereview.chromium.org/7870003
http://code.google.com/p/v8/source/detail?r=9251
Modified:
/branches/experimental/gc/src/mark-compact.cc
/branches/experimental/gc/src/spaces.cc
/branches/experimental/gc/src/spaces.h
=======================================
--- /branches/experimental/gc/src/mark-compact.cc Sat Sep 10 07:48:09 2011
+++ /branches/experimental/gc/src/mark-compact.cc Tue Sep 13 02:24:38 2011
@@ -2576,10 +2576,16 @@
int size = object->Size();
- // This should never fail as we are in always allocate scope.
- Object* target = space->AllocateRaw(size)->ToObjectUnchecked();
-
- MigrateObject(HeapObject::cast(target)->address(),
+ MaybeObject* target = space->AllocateRaw(size);
+ if (target->IsFailure()) {
+ // OS refused to give us memory.
+ V8::FatalProcessOutOfMemory("Evacuation");
+ return;
+ }
+
+ Object* target_object = target->ToObjectUnchecked();
+
+ MigrateObject(HeapObject::cast(target_object)->address(),
object_addr,
size,
space->identity());
@@ -2599,7 +2605,19 @@
ASSERT(p->IsEvacuationCandidate() ||
p->IsFlagSet(Page::RESCAN_ON_EVACUATION));
if (p->IsEvacuationCandidate()) {
- EvacuateLiveObjectsFromPage(p);
+ // During compaction we might have to request a new page.
+ // Check that space still have room for that.
+ if (static_cast<PagedSpace*>(p->owner())->CanExpand()) {
+ EvacuateLiveObjectsFromPage(p);
+ } else {
+ // Without room for expansion evacuation is not guaranteed to
succeed.
+ // Pessimistically abandon unevacuated pages.
+ for (int j = i; j < npages; j++) {
+ evacuation_candidates_[j]->ClearEvacuationCandidate();
+ evacuation_candidates_[j]->SetFlag(Page::RESCAN_ON_EVACUATION);
+ }
+ return;
+ }
}
}
}
@@ -2807,10 +2825,14 @@
PagedSpace* space = static_cast<PagedSpace*>(p->owner());
p->ClearFlag(MemoryChunk::RESCAN_ON_EVACUATION);
- SweepPrecisely(space,
- p,
- SWEEP_AND_VISIT_LIVE_OBJECTS,
- &updating_visitor);
+ if (space->identity() == OLD_DATA_SPACE) {
+ SweepConservatively(space, p);
+ } else {
+ SweepPrecisely(space,
+ p,
+ SWEEP_AND_VISIT_LIVE_OBJECTS,
+ &updating_visitor);
+ }
}
}
=======================================
--- /branches/experimental/gc/src/spaces.cc Thu Sep 8 05:15:24 2011
+++ /branches/experimental/gc/src/spaces.cc Tue Sep 13 02:24:38 2011
@@ -721,8 +721,7 @@
return Failure::Exception();
}
-
-bool PagedSpace::Expand() {
+bool PagedSpace::CanExpand() {
ASSERT(max_capacity_ % Page::kObjectAreaSize == 0);
ASSERT(Capacity() % Page::kObjectAreaSize == 0);
@@ -733,6 +732,12 @@
// Are we going to exceed capacity for this space?
if ((Capacity() + Page::kPageSize) > max_capacity_) return false;
+ return true;
+}
+
+bool PagedSpace::Expand() {
+ if (!CanExpand()) return false;
+
Page* p = heap()->isolate()->memory_allocator()->
AllocatePage(this, executable());
if (p == NULL) return false;
=======================================
--- /branches/experimental/gc/src/spaces.h Tue Sep 6 08:11:38 2011
+++ /branches/experimental/gc/src/spaces.h Tue Sep 13 02:24:38 2011
@@ -1492,6 +1492,8 @@
void EvictEvacuationCandidatesFromFreeLists();
+ bool CanExpand();
+
protected:
// Maximum capacity of this space.
intptr_t max_capacity_;
--
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