133 lines
5.6 KiB
C++
133 lines
5.6 KiB
C++
/*
|
|
* Copyright (C) 2014 The Android Open Source Project
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#ifndef ART_RUNTIME_GC_REFERENCE_PROCESSOR_H_
|
|
#define ART_RUNTIME_GC_REFERENCE_PROCESSOR_H_
|
|
|
|
#include "base/locks.h"
|
|
#include "jni.h"
|
|
#include "reference_queue.h"
|
|
#include "runtime_globals.h"
|
|
|
|
namespace art {
|
|
|
|
class IsMarkedVisitor;
|
|
class TimingLogger;
|
|
|
|
namespace mirror {
|
|
class Class;
|
|
class FinalizerReference;
|
|
class Object;
|
|
class Reference;
|
|
} // namespace mirror
|
|
|
|
namespace gc {
|
|
|
|
namespace collector {
|
|
class GarbageCollector;
|
|
} // namespace collector
|
|
|
|
class Heap;
|
|
|
|
// Used to process java.lang.ref.Reference instances concurrently or paused.
|
|
class ReferenceProcessor {
|
|
public:
|
|
ReferenceProcessor();
|
|
|
|
// Initialize for a reference processing pass. Called before suspending weak
|
|
// access.
|
|
void Setup(Thread* self,
|
|
collector::GarbageCollector* collector,
|
|
bool concurrent,
|
|
bool clear_soft_references)
|
|
REQUIRES(!Locks::reference_processor_lock_);
|
|
// Enqueue all types of java.lang.ref.References, and mark through finalizers.
|
|
// Assumes there is no concurrent mutator-driven marking, i.e. all potentially
|
|
// mutator-accessible objects should be marked before this.
|
|
void ProcessReferences(Thread* self, TimingLogger* timings)
|
|
REQUIRES_SHARED(Locks::mutator_lock_)
|
|
REQUIRES(Locks::heap_bitmap_lock_)
|
|
REQUIRES(!Locks::reference_processor_lock_);
|
|
|
|
// The slow path bool is contained in the reference class object, can only be set once
|
|
// Only allow setting this with mutators suspended so that we can avoid using a lock in the
|
|
// GetReferent fast path as an optimization.
|
|
void EnableSlowPath() REQUIRES_SHARED(Locks::mutator_lock_);
|
|
void BroadcastForSlowPath(Thread* self);
|
|
// Decode the referent, may block if references are being processed. In the normal
|
|
// no-read-barrier or Baker-read-barrier cases, we assume reference is not a PhantomReference.
|
|
ObjPtr<mirror::Object> GetReferent(Thread* self, ObjPtr<mirror::Reference> reference)
|
|
REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!Locks::reference_processor_lock_);
|
|
// Collects the cleared references and returns a task, to be executed after FinishGC, that will
|
|
// enqueue all of them.
|
|
SelfDeletingTask* CollectClearedReferences(Thread* self) REQUIRES(!Locks::mutator_lock_);
|
|
void DelayReferenceReferent(ObjPtr<mirror::Class> klass,
|
|
ObjPtr<mirror::Reference> ref,
|
|
collector::GarbageCollector* collector)
|
|
REQUIRES_SHARED(Locks::mutator_lock_);
|
|
void UpdateRoots(IsMarkedVisitor* visitor)
|
|
REQUIRES_SHARED(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
|
|
// Make a circular list with reference if it is not enqueued. Uses the finalizer queue lock.
|
|
bool MakeCircularListIfUnenqueued(ObjPtr<mirror::FinalizerReference> reference)
|
|
REQUIRES_SHARED(Locks::mutator_lock_)
|
|
REQUIRES(!Locks::reference_processor_lock_,
|
|
!Locks::reference_queue_finalizer_references_lock_);
|
|
void ClearReferent(ObjPtr<mirror::Reference> ref)
|
|
REQUIRES_SHARED(Locks::mutator_lock_)
|
|
REQUIRES(!Locks::reference_processor_lock_);
|
|
uint32_t ForwardSoftReferences(TimingLogger* timings)
|
|
REQUIRES_SHARED(Locks::mutator_lock_);
|
|
|
|
private:
|
|
bool SlowPathEnabled() REQUIRES_SHARED(Locks::mutator_lock_);
|
|
// Called by ProcessReferences.
|
|
void DisableSlowPath(Thread* self) REQUIRES(Locks::reference_processor_lock_)
|
|
REQUIRES_SHARED(Locks::mutator_lock_);
|
|
// Wait until reference processing is done.
|
|
void WaitUntilDoneProcessingReferences(Thread* self)
|
|
REQUIRES_SHARED(Locks::mutator_lock_)
|
|
REQUIRES(Locks::reference_processor_lock_);
|
|
// Collector which is clearing references, used by the GetReferent to return referents which are
|
|
// already marked. Only updated by thread currently running GC.
|
|
// Guarded by reference_processor_lock_ when not read by collector. Only the collector changes
|
|
// it.
|
|
collector::GarbageCollector* collector_;
|
|
// Reference processor state. Only valid while weak reference processing is suspended.
|
|
// Used by GetReferent and friends to return early.
|
|
enum class RpState : uint8_t { kStarting, kInitMarkingDone, kInitClearingDone };
|
|
RpState rp_state_ GUARDED_BY(Locks::reference_processor_lock_);
|
|
bool concurrent_; // Running concurrently with mutator? Only used by GC thread.
|
|
bool clear_soft_references_; // Only used by GC thread.
|
|
|
|
// Condition that people wait on if they attempt to get the referent of a reference while
|
|
// processing is in progress. Broadcast when an empty checkpoint is requested, but not for other
|
|
// checkpoints or thread suspensions. See mutator_gc_coord.md.
|
|
ConditionVariable condition_ GUARDED_BY(Locks::reference_processor_lock_);
|
|
// Reference queues used by the GC.
|
|
ReferenceQueue soft_reference_queue_;
|
|
ReferenceQueue weak_reference_queue_;
|
|
ReferenceQueue finalizer_reference_queue_;
|
|
ReferenceQueue phantom_reference_queue_;
|
|
ReferenceQueue cleared_references_;
|
|
|
|
DISALLOW_COPY_AND_ASSIGN(ReferenceProcessor);
|
|
};
|
|
|
|
} // namespace gc
|
|
} // namespace art
|
|
|
|
#endif // ART_RUNTIME_GC_REFERENCE_PROCESSOR_H_
|