Remove first GC pause.
Fixed error where we were prefetching the address of address of
objects.
Remove first paused by removing get dirty cards and replacing it
with card aging. We now age the cards before doing the checkpoint
instead of clearing them. This lets us know which cards were
dirtied before the start of the GC and which cards were dirtied
after.
Optimized FreeList slightly.
Change-Id: I39d6aac1839476d7541d83970c8b27b266e8a117
diff --git a/src/gc/mark_sweep.cc b/src/gc/mark_sweep.cc
index 4662cf6..f2617e4 100644
--- a/src/gc/mark_sweep.cc
+++ b/src/gc/mark_sweep.cc
@@ -51,6 +51,7 @@
static const bool kProfileLargeObjects = false;
static const bool kMeasureOverhead = false;
static const bool kCountTasks = false;
+static const bool kCountJavaLangRefs = false;
class SetFingerVisitor {
public:
@@ -83,6 +84,7 @@
large_object_test_(0), large_object_mark_(0),
classes_marked_(0), overhead_time_(0),
work_chunks_created_(0), work_chunks_deleted_(0),
+ reference_count_(0),
gc_barrier_(new Barrier),
large_object_lock_("large object lock") {
DCHECK(mark_stack_ != NULL);
@@ -272,8 +274,7 @@
}
void operator ()(const Object* obj, const Object* ref, MemberOffset offset, bool is_static) const
- SHARED_LOCKS_REQUIRED(Locks::heap_bitmap_lock_,
- Locks::mutator_lock_) {
+ NO_THREAD_SAFETY_ANALYSIS {
mark_sweep_->CheckReference(obj, ref, offset, is_static);
}
@@ -327,7 +328,7 @@
MarkSweep* const mark_sweep_;
};
-void MarkSweep::ScanGrayObjects() {
+void MarkSweep::ScanGrayObjects(byte minimum_age) {
const Spaces& spaces = heap_->GetSpaces();
CardTable* card_table = heap_->GetCardTable();
ScanObjectVisitor visitor(this);
@@ -339,7 +340,7 @@
byte* end = space->End();
// Image spaces are handled properly since live == marked for them.
SpaceBitmap* mark_bitmap = space->GetMarkBitmap();
- card_table->Scan(mark_bitmap, begin, end, visitor, IdentityFunctor());
+ card_table->Scan(mark_bitmap, begin, end, visitor, VoidFunctor(), minimum_age);
}
}
@@ -373,7 +374,7 @@
uintptr_t end = reinterpret_cast<uintptr_t>(space->End());
SpaceBitmap* live_bitmap = space->GetLiveBitmap();
DCHECK(live_bitmap != NULL);
- live_bitmap->VisitMarkedRange(begin, end, visitor, IdentityFunctor());
+ live_bitmap->VisitMarkedRange(begin, end, visitor, VoidFunctor());
}
}
}
@@ -436,7 +437,7 @@
}
}
if (kDisableFinger) {
- active_bitmap->VisitMarkedRange(begin, end, image_root_visitor, IdentityFunctor());
+ active_bitmap->VisitMarkedRange(begin, end, image_root_visitor, VoidFunctor());
} else {
active_bitmap->VisitMarkedRange(begin, end, image_root_visitor, finger_visitor);
}
@@ -452,8 +453,8 @@
!reinterpret_cast<MarkSweep*>(arg)->GetHeap()->GetLiveBitmap()->Test(object);
}
-void MarkSweep::RecursiveMarkDirtyObjects() {
- ScanGrayObjects();
+void MarkSweep::RecursiveMarkDirtyObjects(byte minimum_age) {
+ ScanGrayObjects(minimum_age);
ProcessMarkStack();
}
@@ -569,8 +570,8 @@
virtual void Run(Thread* thread) NO_THREAD_SAFETY_ANALYSIS {
// Note: self is not necessarily equal to thread since thread may be suspended.
Thread* self = Thread::Current();
- DCHECK(thread == self || thread->IsSuspended() || thread->GetState() == kWaitingPerformingGc)
- << thread->GetState();
+ CHECK(thread == self || thread->IsSuspended() || thread->GetState() == kWaitingPerformingGc)
+ << thread->GetState() << " thread " << thread << " self " << self;
WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
thread->VisitRoots(MarkSweep::MarkObjectCallback, mark_sweep_);
mark_sweep_->GetBarrier().Pass(self);
@@ -585,12 +586,12 @@
}
void MarkSweep::MarkRootsCheckpoint() {
- UniquePtr<CheckpointMarkThreadRoots> check_point(new CheckpointMarkThreadRoots(this));
+ CheckpointMarkThreadRoots check_point(this);
ThreadList* thread_list = Runtime::Current()->GetThreadList();
// Increment the count of the barrier. If all of the checkpoints have already been finished then
// will hit 0 and continue. Otherwise we are still waiting for some checkpoints, so the counter
// will go positive and we will unblock when it hits zero.
- gc_barrier_->Increment(Thread::Current(), thread_list->RunCheckpoint(check_point.get()));
+ gc_barrier_->Increment(Thread::Current(), thread_list->RunCheckpoint(&check_point));
}
void MarkSweep::SweepCallback(size_t num_ptrs, Object** ptrs, void* arg) {
@@ -675,7 +676,7 @@
freed_bytes_ += freed_bytes;
logger.AddSplit("FreeList");
allocations->Reset();
- logger.AddSplit("Reset stack");
+ logger.AddSplit("ResetStack");
}
void MarkSweep::Sweep(TimingLogger& timings, bool partial, bool swap_bitmaps) {
@@ -799,6 +800,9 @@
DCHECK(klass->IsReferenceClass());
Object* pending = obj->GetFieldObject<Object*>(heap_->GetReferencePendingNextOffset(), false);
Object* referent = heap_->GetReferenceReferent(obj);
+ if (kCountJavaLangRefs) {
+ ++reference_count_;
+ }
if (pending == NULL && referent != NULL && !IsMarked(referent)) {
Object** list = NULL;
if (klass->IsSoftReferenceClass()) {
@@ -826,9 +830,7 @@
}
void operator ()(const Object* /* obj */, const Object* ref, const MemberOffset& /* offset */,
- bool /* is_static */) const
- EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_)
- SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+ bool /* is_static */) const EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) {
mark_sweep_->MarkObject(ref);
}
@@ -963,13 +965,9 @@
virtual void Run(Thread* self) {
int index;
while ((index = index_++) < length_) {
- static const size_t prefetch_look_ahead = 4;
if (kUseMarkStackPrefetch) {
- if (index + prefetch_look_ahead < length_) {
- __builtin_prefetch(&data_[index + prefetch_look_ahead]);
- } else {
- __builtin_prefetch(&data_[length_ - 1]);
- }
+ static const size_t prefetch_look_ahead = 1;
+ __builtin_prefetch(data_[std::min(index + prefetch_look_ahead, length_ - 1)]);
}
Object* obj = data_[index];
DCHECK(obj != NULL);
@@ -1203,25 +1201,29 @@
}
MarkSweep::~MarkSweep() {
- if (class_count_ != 0 || array_count_ != 0 || other_count_ != 0) {
- LOG(INFO) << "MarkSweep scanned classes=" << class_count_ << " arrays=" << array_count_
- << " other=" << other_count_;
+ if (kCountScannedTypes) {
+ VLOG(gc) << "MarkSweep scanned classes=" << class_count_ << " arrays=" << array_count_
+ << " other=" << other_count_;
}
if (kCountTasks) {
- LOG(INFO) << "Total number of work chunks allocated: " << work_chunks_created_;
+ VLOG(gc) << "Total number of work chunks allocated: " << work_chunks_created_;
}
if (kMeasureOverhead) {
- LOG(INFO) << "Overhead time " << PrettyDuration(overhead_time_);
+ VLOG(gc) << "Overhead time " << PrettyDuration(overhead_time_);
}
if (kProfileLargeObjects) {
- LOG(INFO) << "Large objects tested " << large_object_test_ << " marked " << large_object_mark_;
+ VLOG(gc) << "Large objects tested " << large_object_test_ << " marked " << large_object_mark_;
}
if (kCountClassesMarked) {
- LOG(INFO) << "Classes marked " << classes_marked_;
+ VLOG(gc) << "Classes marked " << classes_marked_;
+ }
+
+ if (kCountJavaLangRefs) {
+ VLOG(gc) << "References scanned " << reference_count_;
}
// Ensure that the mark stack is empty.