Refactor and optimize GC code.
Fixed the reference cache mod union table, and re-enabled it by
default. Added a boolean flag to count how many null objects,
immune, fast path, slow path objects we marked.
Slight speedup in mark stack processing, large speedup in image mod
union table scanning.
EvaluateAndApplyChanges Before:
Process mark stack time for full GC only:
12.464089s, 12.357870s, 12.538028s
Time spent marking mod image union table ~240ms.
After:
Process mark stack time: 12.299375s, 12.217142s, 12.187076s
Time spent marking mod image union table ~40ms.
TODO: Refactor reference visiting logic into mirror::Object.
Change-Id: I91889ded9d3f2bf127bc0051c1b1ff77e792e94f
diff --git a/runtime/gc/collector/semi_space.h b/runtime/gc/collector/semi_space.h
index 7cc7f9b..0d77f29 100644
--- a/runtime/gc/collector/semi_space.h
+++ b/runtime/gc/collector/semi_space.h
@@ -66,18 +66,19 @@
// If true, use remembered sets in the generational mode.
static constexpr bool kUseRememberedSet = true;
- explicit SemiSpace(Heap* heap, bool generational = false,
- const std::string& name_prefix = "");
+ explicit SemiSpace(Heap* heap, bool generational = false, const std::string& name_prefix = "");
~SemiSpace() {}
- virtual void InitializePhase();
- virtual void MarkingPhase() EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_);
- virtual void ReclaimPhase() EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_);
- virtual void FinishPhase() EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_);
- virtual void MarkReachableObjects()
+ virtual void InitializePhase() OVERRIDE;
+ virtual void MarkingPhase() OVERRIDE EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_)
+ LOCKS_EXCLUDED(Locks::heap_bitmap_lock_);
+ virtual void ReclaimPhase() OVERRIDE EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_)
+ LOCKS_EXCLUDED(Locks::heap_bitmap_lock_);
+ virtual void FinishPhase() OVERRIDE EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_);
+ void MarkReachableObjects()
EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
- virtual GcType GetGcType() const {
+ virtual GcType GetGcType() const OVERRIDE {
return kGcTypePartial;
}
virtual CollectorType GetCollectorType() const OVERRIDE {
@@ -112,12 +113,13 @@
// Bind the live bits to the mark bits of bitmaps for spaces that are never collected, ie
// the image. Mark that portion of the heap as immune.
- virtual void BindBitmaps() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+ virtual void BindBitmaps() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
+ LOCKS_EXCLUDED(Locks::heap_bitmap_lock_);
void UnBindBitmaps()
EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
- void ProcessReferences(Thread* self)
+ void ProcessReferences(Thread* self) EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_)
EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_);
// Sweeps unmarked objects to complete the garbage collection.
@@ -126,22 +128,9 @@
// Sweeps unmarked objects to complete the garbage collection.
void SweepLargeObjects(bool swap_bitmaps) EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
- // Sweep only pointers within an array. WARNING: Trashes objects.
- void SweepArray(accounting::ObjectStack* allocation_stack_, bool swap_bitmaps)
- EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
-
- // TODO: enable thread safety analysis when in use by multiple worker threads.
- template <typename MarkVisitor>
- void ScanObjectVisit(const mirror::Object* obj, const MarkVisitor& visitor)
- NO_THREAD_SAFETY_ANALYSIS;
-
void SweepSystemWeaks()
SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
- template <typename Visitor>
- static void VisitObjectReferencesAndClass(mirror::Object* obj, const Visitor& visitor)
- EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
-
static void MarkRootCallback(mirror::Object** root, void* arg, uint32_t /*tid*/,
RootType /*root_type*/)
EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
@@ -158,15 +147,18 @@
protected:
// Returns null if the object is not marked, otherwise returns the forwarding address (same as
// object for non movable things).
- mirror::Object* GetMarkedForwardAddress(mirror::Object* object) const;
+ mirror::Object* GetMarkedForwardAddress(mirror::Object* object) const
+ EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_)
+ SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
static mirror::Object* MarkedForwardingAddressCallback(mirror::Object* object, void* arg)
+ EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_)
SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
// Marks or unmarks a large object based on whether or not set is true. If set is true, then we
// mark, otherwise we unmark.
bool MarkLargeObject(const mirror::Object* obj)
- EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_);
+ EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
// Expand mark stack to 2x its current size.
void ResizeMarkStack(size_t new_size);
@@ -174,48 +166,8 @@
// Returns true if we should sweep the space.
virtual bool ShouldSweepSpace(space::ContinuousSpace* space) const;
- static void VerifyRootCallback(const mirror::Object* root, void* arg, size_t vreg,
- const StackVisitor *visitor);
-
- void VerifyRoot(const mirror::Object* root, size_t vreg, const StackVisitor* visitor)
- NO_THREAD_SAFETY_ANALYSIS;
-
- template <typename Visitor>
- static void VisitInstanceFieldsReferences(const mirror::Class* klass, const mirror::Object* obj,
- const Visitor& visitor)
- SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
-
- // Visit the header, static field references, and interface pointers of a class object.
- template <typename Visitor>
- static void VisitClassReferences(const mirror::Class* klass, const mirror::Object* obj,
- const Visitor& visitor)
- SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
-
- template <typename Visitor>
- static void VisitStaticFieldsReferences(const mirror::Class* klass, const Visitor& visitor)
- SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
-
- template <typename Visitor>
- static void VisitFieldsReferences(const mirror::Object* obj, uint32_t ref_offsets, bool is_static,
- const Visitor& visitor)
- SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
-
- // Visit all of the references in an object array.
- template <typename Visitor>
- static void VisitObjectArrayReferences(const mirror::ObjectArray<mirror::Object>* array,
- const Visitor& visitor)
- SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_);
-
- // Visits the header and field references of a data object.
- template <typename Visitor>
- static void VisitOtherReferences(const mirror::Class* klass, const mirror::Object* obj,
- const Visitor& visitor)
- SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_, Locks::mutator_lock_) {
- return VisitInstanceFieldsReferences(klass, obj, visitor);
- }
-
// Push an object onto the mark stack.
- inline void MarkStackPush(mirror::Object* obj);
+ void MarkStackPush(mirror::Object* obj);
void UpdateAndMarkModUnion()
EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
@@ -229,15 +181,6 @@
void ProcessMarkStack()
EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
- void EnqueueFinalizerReferences(mirror::Object** ref)
- EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
-
- void PreserveSomeSoftReferences(mirror::Object** ref)
- EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
-
- void ClearWhiteReferences(mirror::Object** list)
- EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
-
void ProcessReferences(mirror::Object** soft_references, bool clear_soft_references,
mirror::Object** weak_references,
mirror::Object** finalizer_references,