Fix mark stack expand race.
We now guard parallel mark stack pushing with a lock. This is
only used by checkpoint root marking. I did not observe a
significant slowdown by looking at ritzperf and maps, but it may
be worth reinvestigating in the future.
Also a bit of refactoring.
Bug: 10113123
Change-Id: Ifcb12d14df437e2aea9a1165a9568054f80d91b3
diff --git a/runtime/gc/collector/mark_sweep.h b/runtime/gc/collector/mark_sweep.h
index dbec3e9..d5f4042 100644
--- a/runtime/gc/collector/mark_sweep.h
+++ b/runtime/gc/collector/mark_sweep.h
@@ -305,8 +305,9 @@
void VerifyRoots()
NO_THREAD_SAFETY_ANALYSIS;
- // Expand mark stack to 2x its current size. Thread safe.
- void ExpandMarkStack();
+ // Expand mark stack to 2x its current size.
+ void ExpandMarkStack() EXCLUSIVE_LOCKS_REQUIRED(mark_stack_lock_);
+ void ResizeMarkStack(size_t new_size) EXCLUSIVE_LOCKS_REQUIRED(mark_stack_lock_);
// Returns how many threads we should use for the current GC phase based on if we are paused,
// whether or not we care about pauses.
@@ -445,7 +446,7 @@
UniquePtr<Barrier> gc_barrier_;
Mutex large_object_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
- Mutex mark_stack_expand_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
+ Mutex mark_stack_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
const bool is_concurrent_;