--- a/make/hotspot/lib/JvmFeatures.gmk Wed Oct 18 21:05:09 2017 +0000
+++ b/make/hotspot/lib/JvmFeatures.gmk Wed Oct 18 22:10:28 2017 +0000
@@ -132,6 +132,7 @@
cms/ g1/ parallel/
JVM_EXCLUDE_FILES += \
concurrentGCThread.cpp \
+ suspendibleThreadSet.cpp \
plab.cpp
JVM_EXCLUDE_FILES += \
g1MemoryPool.cpp \
--- a/src/hotspot/share/gc/cms/concurrentMarkSweepGeneration.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/cms/concurrentMarkSweepGeneration.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -55,6 +55,7 @@
#include "gc/shared/referencePolicy.hpp"
#include "gc/shared/strongRootsScope.hpp"
#include "gc/shared/taskqueue.inline.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "logging/log.hpp"
#include "logging/logStream.hpp"
#include "memory/allocation.hpp"
@@ -5224,6 +5225,11 @@
pt.print_all_references();
}
+ {
+ GCTraceTime(Debug, gc, phases) t("Weak Processing", _gc_timer_cm);
+ WeakProcessor::weak_oops_do(&_is_alive_closure, &cmsKeepAliveClosure, &cmsDrainMarkingStackClosure);
+ }
+
// This is the point where the entire marking should have completed.
verify_work_stacks_empty();
--- a/src/hotspot/share/gc/cms/parNewGeneration.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/cms/parNewGeneration.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -46,6 +46,7 @@
#include "gc/shared/spaceDecorator.hpp"
#include "gc/shared/strongRootsScope.hpp"
#include "gc/shared/taskqueue.inline.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "gc/shared/workgroup.hpp"
#include "logging/log.hpp"
#include "logging/logStream.hpp"
@@ -999,6 +1000,8 @@
_gc_tracer.report_tenuring_threshold(tenuring_threshold());
pt.print_all_references();
+ WeakProcessor::weak_oops_do(&is_alive, &keep_alive, &evacuate_followers);
+
if (!promotion_failed()) {
// Swap the survivor spaces.
eden()->clear(SpaceDecorator::Mangle);
--- a/src/hotspot/share/gc/g1/concurrentG1RefineThread.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/concurrentG1RefineThread.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2017, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -27,7 +27,7 @@
#include "gc/g1/concurrentG1RefineThread.hpp"
#include "gc/g1/g1CollectedHeap.inline.hpp"
#include "gc/g1/g1RemSet.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
#include "logging/log.hpp"
#include "memory/resourceArea.hpp"
#include "runtime/handles.inline.hpp"
--- a/src/hotspot/share/gc/g1/concurrentMarkThread.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/concurrentMarkThread.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -30,12 +30,12 @@
#include "gc/g1/g1ConcurrentMark.inline.hpp"
#include "gc/g1/g1MMUTracker.hpp"
#include "gc/g1/g1Policy.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
#include "gc/g1/vm_operations_g1.hpp"
#include "gc/shared/concurrentGCPhaseManager.hpp"
#include "gc/shared/gcId.hpp"
#include "gc/shared/gcTrace.hpp"
#include "gc/shared/gcTraceTime.inline.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
#include "logging/log.hpp"
#include "memory/resourceArea.hpp"
#include "runtime/vmThread.hpp"
--- a/src/hotspot/share/gc/g1/g1CardLiveData.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/g1CardLiveData.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -26,7 +26,7 @@
#include "gc/g1/g1CollectedHeap.inline.hpp"
#include "gc/g1/g1ConcurrentMark.inline.hpp"
#include "gc/g1/g1CardLiveData.inline.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
#include "gc/shared/workgroup.hpp"
#include "logging/log.hpp"
#include "memory/universe.hpp"
--- a/src/hotspot/share/gc/g1/g1CollectedHeap.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/g1CollectedHeap.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -57,7 +57,6 @@
#include "gc/g1/heapRegion.inline.hpp"
#include "gc/g1/heapRegionRemSet.hpp"
#include "gc/g1/heapRegionSet.inline.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
#include "gc/g1/vm_operations_g1.hpp"
#include "gc/shared/gcHeapSummary.hpp"
#include "gc/shared/gcId.hpp"
@@ -68,8 +67,10 @@
#include "gc/shared/generationSpec.hpp"
#include "gc/shared/isGCActiveMark.hpp"
#include "gc/shared/preservedMarks.inline.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
#include "gc/shared/referenceProcessor.inline.hpp"
#include "gc/shared/taskqueue.inline.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "logging/log.hpp"
#include "memory/allocation.hpp"
#include "memory/iterator.hpp"
@@ -4128,17 +4129,6 @@
}
};
-void G1CollectedHeap::process_weak_jni_handles() {
- double ref_proc_start = os::elapsedTime();
-
- G1STWIsAliveClosure is_alive(this);
- G1KeepAliveClosure keep_alive(this);
- JNIHandles::weak_oops_do(&is_alive, &keep_alive);
-
- double ref_proc_time = os::elapsedTime() - ref_proc_start;
- g1_policy()->phase_times()->record_ref_proc_time(ref_proc_time * 1000.0);
-}
-
void G1CollectedHeap::preserve_cm_referents(G1ParScanThreadStateSet* per_thread_states) {
// Any reference objects, in the collection set, that were 'discovered'
// by the CM ref processor should have already been copied (either by
@@ -4369,14 +4359,23 @@
process_discovered_references(per_thread_states);
} else {
ref_processor_stw()->verify_no_references_recorded();
- process_weak_jni_handles();
+ }
+
+ G1STWIsAliveClosure is_alive(this);
+ G1KeepAliveClosure keep_alive(this);
+
+ {
+ double start = os::elapsedTime();
+
+ WeakProcessor::weak_oops_do(&is_alive, &keep_alive);
+
+ double time_ms = (os::elapsedTime() - start) * 1000.0;
+ g1_policy()->phase_times()->record_ref_proc_time(time_ms);
}
if (G1StringDedup::is_enabled()) {
double fixup_start = os::elapsedTime();
- G1STWIsAliveClosure is_alive(this);
- G1KeepAliveClosure keep_alive(this);
G1StringDedup::unlink_or_oops_do(&is_alive, &keep_alive, true, g1_policy()->phase_times());
double fixup_time_ms = (os::elapsedTime() - fixup_start) * 1000.0;
--- a/src/hotspot/share/gc/g1/g1CollectedHeap.hpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/g1CollectedHeap.hpp Wed Oct 18 22:10:28 2017 +0000
@@ -303,8 +303,6 @@
void trace_heap(GCWhen::Type when, const GCTracer* tracer);
- void process_weak_jni_handles();
-
// These are macros so that, if the assert fires, we get the correct
// line number, file, etc.
--- a/src/hotspot/share/gc/g1/g1ConcurrentMark.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/g1ConcurrentMark.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -38,7 +38,6 @@
#include "gc/g1/heapRegion.inline.hpp"
#include "gc/g1/heapRegionRemSet.hpp"
#include "gc/g1/heapRegionSet.inline.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
#include "gc/shared/gcId.hpp"
#include "gc/shared/gcTimer.hpp"
#include "gc/shared/gcTrace.hpp"
@@ -46,8 +45,10 @@
#include "gc/shared/genOopClosures.inline.hpp"
#include "gc/shared/referencePolicy.hpp"
#include "gc/shared/strongRootsScope.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
#include "gc/shared/taskqueue.inline.hpp"
#include "gc/shared/vmGCOperations.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "logging/log.hpp"
#include "memory/allocation.hpp"
#include "memory/resourceArea.hpp"
@@ -1603,6 +1604,23 @@
// Is alive closure.
G1CMIsAliveClosure g1_is_alive(g1h);
+ // Instances of the 'Keep Alive' and 'Complete GC' closures used
+ // in serial reference processing. Note these closures are also
+ // used for serially processing (by the the current thread) the
+ // JNI references during parallel reference processing.
+ //
+ // These closures do not need to synchronize with the worker
+ // threads involved in parallel reference processing as these
+ // instances are executed serially by the current thread (e.g.
+ // reference processing is not multi-threaded and is thus
+ // performed by the current thread instead of a gang worker).
+ //
+ // The gang tasks involved in parallel reference processing create
+ // their own instances of these closures, which do their own
+ // synchronization among themselves.
+ G1CMKeepAliveAndDrainClosure g1_keep_alive(this, task(0), true /* is_serial */);
+ G1CMDrainMarkingStackClosure g1_drain_mark_stack(this, task(0), true /* is_serial */);
+
// Inner scope to exclude the cleaning of the string and symbol
// tables from the displayed time.
{
@@ -1617,23 +1635,6 @@
rp->setup_policy(clear_all_soft_refs);
assert(_global_mark_stack.is_empty(), "mark stack should be empty");
- // Instances of the 'Keep Alive' and 'Complete GC' closures used
- // in serial reference processing. Note these closures are also
- // used for serially processing (by the the current thread) the
- // JNI references during parallel reference processing.
- //
- // These closures do not need to synchronize with the worker
- // threads involved in parallel reference processing as these
- // instances are executed serially by the current thread (e.g.
- // reference processing is not multi-threaded and is thus
- // performed by the current thread instead of a gang worker).
- //
- // The gang tasks involved in parallel reference processing create
- // their own instances of these closures, which do their own
- // synchronization among themselves.
- G1CMKeepAliveAndDrainClosure g1_keep_alive(this, task(0), true /* is_serial */);
- G1CMDrainMarkingStackClosure g1_drain_mark_stack(this, task(0), true /* is_serial */);
-
// We need at least one active thread. If reference processing
// is not multi-threaded we use the current (VMThread) thread,
// otherwise we use the work gang from the G1CollectedHeap and
@@ -1687,6 +1688,11 @@
assert(!rp->discovery_enabled(), "Post condition");
}
+ {
+ GCTraceTime(Debug, gc, phases) debug("Weak Processing", _gc_timer_cm);
+ WeakProcessor::weak_oops_do(&g1_is_alive, &g1_keep_alive, &g1_drain_mark_stack);
+ }
+
if (has_overflown()) {
// We can not trust g1_is_alive if the marking stack overflowed
return;
--- a/src/hotspot/share/gc/g1/g1ConcurrentMark.inline.hpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/g1ConcurrentMark.inline.hpp Wed Oct 18 22:10:28 2017 +0000
@@ -29,7 +29,7 @@
#include "gc/g1/g1ConcurrentMark.hpp"
#include "gc/g1/g1ConcurrentMarkBitMap.inline.hpp"
#include "gc/g1/g1ConcurrentMarkObjArrayProcessor.inline.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
#include "gc/shared/taskqueue.inline.hpp"
#include "utilities/bitMap.inline.hpp"
--- a/src/hotspot/share/gc/g1/g1MarkSweep.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/g1MarkSweep.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -43,6 +43,7 @@
#include "gc/shared/modRefBarrierSet.hpp"
#include "gc/shared/referencePolicy.hpp"
#include "gc/shared/space.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "oops/instanceRefKlass.hpp"
#include "oops/oop.inline.hpp"
#include "prims/jvmtiExport.hpp"
@@ -181,6 +182,13 @@
pt.print_all_references();
}
+ {
+ GCTraceTime(Debug, gc, phases) trace("Weak Processing", gc_timer());
+ WeakProcessor::weak_oops_do(&GenMarkSweep::is_alive,
+ &GenMarkSweep::keep_alive,
+ &GenMarkSweep::follow_stack_closure);
+ }
+
// This is the point where the entire marking should have completed.
assert(GenMarkSweep::_marking_stack.is_empty(), "Marking should have completed");
@@ -272,7 +280,7 @@
// Now adjust pointers in remaining weak roots. (All of which should
// have been cleared if they pointed to non-surviving objects.)
- JNIHandles::weak_oops_do(&GenMarkSweep::adjust_pointer_closure);
+ WeakProcessor::oops_do(&GenMarkSweep::adjust_pointer_closure);
if (G1StringDedup::is_enabled()) {
G1StringDedup::oops_do(&GenMarkSweep::adjust_pointer_closure);
--- a/src/hotspot/share/gc/g1/g1RemSet.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/g1RemSet.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -36,8 +36,8 @@
#include "gc/g1/heapRegion.inline.hpp"
#include "gc/g1/heapRegionManager.inline.hpp"
#include "gc/g1/heapRegionRemSet.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
#include "gc/shared/gcTraceTime.inline.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
#include "memory/iterator.hpp"
#include "memory/resourceArea.hpp"
#include "oops/oop.inline.hpp"
--- a/src/hotspot/share/gc/g1/g1StringDedupThread.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/g1StringDedupThread.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -28,7 +28,7 @@
#include "gc/g1/g1StringDedupQueue.hpp"
#include "gc/g1/g1StringDedupTable.hpp"
#include "gc/g1/g1StringDedupThread.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
#include "logging/log.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/atomic.hpp"
--- a/src/hotspot/share/gc/g1/g1YoungRemSetSamplingThread.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/g1/g1YoungRemSetSamplingThread.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -29,7 +29,7 @@
#include "gc/g1/g1YoungRemSetSamplingThread.hpp"
#include "gc/g1/heapRegion.inline.hpp"
#include "gc/g1/heapRegionRemSet.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
#include "runtime/mutexLocker.hpp"
G1YoungRemSetSamplingThread::G1YoungRemSetSamplingThread() :
--- a/src/hotspot/share/gc/g1/suspendibleThreadSet.cpp Wed Oct 18 21:05:09 2017 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,134 +0,0 @@
-/*
- * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-#include "precompiled.hpp"
-#include "gc/g1/suspendibleThreadSet.hpp"
-#include "runtime/mutexLocker.hpp"
-#include "runtime/semaphore.hpp"
-#include "runtime/thread.inline.hpp"
-
-uint SuspendibleThreadSet::_nthreads = 0;
-uint SuspendibleThreadSet::_nthreads_stopped = 0;
-bool SuspendibleThreadSet::_suspend_all = false;
-double SuspendibleThreadSet::_suspend_all_start = 0.0;
-
-static Semaphore* _synchronize_wakeup = NULL;
-
-void SuspendibleThreadSet_init() {
- assert(_synchronize_wakeup == NULL, "STS already initialized");
- _synchronize_wakeup = new Semaphore();
-}
-
-bool SuspendibleThreadSet::is_synchronized() {
- assert_lock_strong(STS_lock);
- assert(_nthreads_stopped <= _nthreads, "invariant");
- return _nthreads_stopped == _nthreads;
-}
-
-void SuspendibleThreadSet::join() {
- assert(!Thread::current()->is_suspendible_thread(), "Thread already joined");
- MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
- while (_suspend_all) {
- ml.wait(Mutex::_no_safepoint_check_flag);
- }
- _nthreads++;
- DEBUG_ONLY(Thread::current()->set_suspendible_thread();)
-}
-
-void SuspendibleThreadSet::leave() {
- assert(Thread::current()->is_suspendible_thread(), "Thread not joined");
- MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
- assert(_nthreads > 0, "Invalid");
- DEBUG_ONLY(Thread::current()->clear_suspendible_thread();)
- _nthreads--;
- if (_suspend_all && is_synchronized()) {
- // This leave completes a request, so inform the requestor.
- _synchronize_wakeup->signal();
- }
-}
-
-void SuspendibleThreadSet::yield() {
- assert(Thread::current()->is_suspendible_thread(), "Must have joined");
- MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
- if (_suspend_all) {
- _nthreads_stopped++;
- if (is_synchronized()) {
- if (ConcGCYieldTimeout > 0) {
- double now = os::elapsedTime();
- guarantee((now - _suspend_all_start) * 1000.0 < (double)ConcGCYieldTimeout, "Long delay");
- }
- // This yield completes the request, so inform the requestor.
- _synchronize_wakeup->signal();
- }
- while (_suspend_all) {
- ml.wait(Mutex::_no_safepoint_check_flag);
- }
- assert(_nthreads_stopped > 0, "Invalid");
- _nthreads_stopped--;
- }
-}
-
-void SuspendibleThreadSet::synchronize() {
- assert(Thread::current()->is_VM_thread(), "Must be the VM thread");
- if (ConcGCYieldTimeout > 0) {
- _suspend_all_start = os::elapsedTime();
- }
- {
- MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
- assert(!_suspend_all, "Only one at a time");
- _suspend_all = true;
- if (is_synchronized()) {
- return;
- }
- } // Release lock before semaphore wait.
-
- // Semaphore initial count is zero. To reach here, there must be at
- // least one not yielded thread in the set, e.g. is_synchronized()
- // was false before the lock was released. A thread in the set will
- // signal the semaphore iff it is the last to yield or leave while
- // there is an active suspend request. So there will be exactly one
- // signal, which will increment the semaphore count to one, which
- // will then be consumed by this wait, returning it to zero. No
- // thread can exit yield or enter the set until desynchronize is
- // called, so there are no further opportunities for the semaphore
- // being signaled until we get back here again for some later
- // synchronize call. Hence, there is no need to re-check for
- // is_synchronized after the wait; it will always be true there.
- _synchronize_wakeup->wait();
-
-#ifdef ASSERT
- MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
- assert(_suspend_all, "STS not synchronizing");
- assert(is_synchronized(), "STS not synchronized");
-#endif
-}
-
-void SuspendibleThreadSet::desynchronize() {
- assert(Thread::current()->is_VM_thread(), "Must be the VM thread");
- MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
- assert(_suspend_all, "STS not synchronizing");
- assert(is_synchronized(), "STS not synchronized");
- _suspend_all = false;
- ml.notify_all();
-}
--- a/src/hotspot/share/gc/g1/suspendibleThreadSet.hpp Wed Oct 18 21:05:09 2017 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,119 +0,0 @@
-/*
- * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-#ifndef SHARE_VM_GC_G1_SUSPENDIBLETHREADSET_HPP
-#define SHARE_VM_GC_G1_SUSPENDIBLETHREADSET_HPP
-
-#include "memory/allocation.hpp"
-
-// A SuspendibleThreadSet is a set of threads that can be suspended.
-// A thread can join and later leave the set, and periodically yield.
-// If some thread (not in the set) requests, via synchronize(), that
-// the threads be suspended, then the requesting thread is blocked
-// until all the threads in the set have yielded or left the set. Threads
-// may not enter the set when an attempted suspension is in progress. The
-// suspending thread later calls desynchronize(), allowing the suspended
-// threads to continue.
-class SuspendibleThreadSet : public AllStatic {
- friend class SuspendibleThreadSetJoiner;
- friend class SuspendibleThreadSetLeaver;
-
-private:
- static uint _nthreads;
- static uint _nthreads_stopped;
- static bool _suspend_all;
- static double _suspend_all_start;
-
- static bool is_synchronized();
-
- // Add the current thread to the set. May block if a suspension is in progress.
- static void join();
-
- // Removes the current thread from the set.
- static void leave();
-
-public:
- // Returns true if an suspension is in progress.
- static bool should_yield() { return _suspend_all; }
-
- // Suspends the current thread if a suspension is in progress.
- static void yield();
-
- // Returns when all threads in the set are suspended.
- static void synchronize();
-
- // Resumes all suspended threads in the set.
- static void desynchronize();
-};
-
-class SuspendibleThreadSetJoiner : public StackObj {
-private:
- bool _active;
-
-public:
- SuspendibleThreadSetJoiner(bool active = true) : _active(active) {
- if (_active) {
- SuspendibleThreadSet::join();
- }
- }
-
- ~SuspendibleThreadSetJoiner() {
- if (_active) {
- SuspendibleThreadSet::leave();
- }
- }
-
- bool should_yield() {
- if (_active) {
- return SuspendibleThreadSet::should_yield();
- } else {
- return false;
- }
- }
-
- void yield() {
- assert(_active, "Thread has not joined the suspendible thread set");
- SuspendibleThreadSet::yield();
- }
-};
-
-class SuspendibleThreadSetLeaver : public StackObj {
-private:
- bool _active;
-
-public:
- SuspendibleThreadSetLeaver(bool active = true) : _active(active) {
- if (_active) {
- SuspendibleThreadSet::leave();
- }
- }
-
- ~SuspendibleThreadSetLeaver() {
- if (_active) {
- SuspendibleThreadSet::join();
- }
- }
-};
-
-#endif // SHARE_VM_GC_G1_SUSPENDIBLETHREADSET_HPP
--- a/src/hotspot/share/gc/parallel/psMarkSweep.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/parallel/psMarkSweep.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -47,6 +47,7 @@
#include "gc/shared/referencePolicy.hpp"
#include "gc/shared/referenceProcessor.hpp"
#include "gc/shared/spaceDecorator.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "logging/log.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/biasedLocking.hpp"
@@ -542,6 +543,11 @@
pt.print_all_references();
}
+ {
+ GCTraceTime(Debug, gc, phases) t("Weak Processing", _gc_timer);
+ WeakProcessor::weak_oops_do(is_alive_closure(), mark_and_push_closure(), follow_stack_closure());
+ }
+
// This is the point where the entire marking should have completed.
assert(_marking_stack.is_empty(), "Marking should have completed");
@@ -617,7 +623,7 @@
// Now adjust pointers in remaining weak roots. (All of which should
// have been cleared if they pointed to non-surviving objects.)
// Global (weak) JNI handles
- JNIHandles::weak_oops_do(adjust_pointer_closure());
+ WeakProcessor::oops_do(adjust_pointer_closure());
CodeBlobToOopClosure adjust_from_blobs(adjust_pointer_closure(), CodeBlobToOopClosure::FixRelocations);
CodeCache::blobs_do(&adjust_from_blobs);
--- a/src/hotspot/share/gc/parallel/psParallelCompact.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/parallel/psParallelCompact.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -52,6 +52,7 @@
#include "gc/shared/referencePolicy.hpp"
#include "gc/shared/referenceProcessor.hpp"
#include "gc/shared/spaceDecorator.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "logging/log.hpp"
#include "memory/resourceArea.hpp"
#include "oops/instanceKlass.inline.hpp"
@@ -2118,6 +2119,11 @@
pt.print_all_references();
}
+ {
+ GCTraceTime(Debug, gc, phases) tm("Weak Processing", &_gc_timer);
+ WeakProcessor::weak_oops_do(is_alive_closure(), &mark_and_push_closure, &follow_stack_closure);
+ }
+
// This is the point where the entire marking should have completed.
assert(cm->marking_stacks_empty(), "Marking should have completed");
@@ -2170,8 +2176,7 @@
// Now adjust pointers in remaining weak roots. (All of which should
// have been cleared if they pointed to non-surviving objects.)
- // Global (weak) JNI handles
- JNIHandles::weak_oops_do(&oop_closure);
+ WeakProcessor::oops_do(&oop_closure);
CodeBlobToOopClosure adjust_from_blobs(&oop_closure, CodeBlobToOopClosure::FixRelocations);
CodeCache::blobs_do(&adjust_from_blobs);
--- a/src/hotspot/share/gc/parallel/psScavenge.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/parallel/psScavenge.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -45,6 +45,7 @@
#include "gc/shared/referencePolicy.hpp"
#include "gc/shared/referenceProcessor.hpp"
#include "gc/shared/spaceDecorator.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "memory/resourceArea.hpp"
#include "logging/log.hpp"
#include "oops/oop.inline.hpp"
@@ -406,14 +407,15 @@
scavenge_midpoint.update();
+ PSKeepAliveClosure keep_alive(promotion_manager);
+ PSEvacuateFollowersClosure evac_followers(promotion_manager);
+
// Process reference objects discovered during scavenge
{
GCTraceTime(Debug, gc, phases) tm("Reference Processing", &_gc_timer);
reference_processor()->setup_policy(false); // not always_clear
reference_processor()->set_active_mt_degree(active_workers);
- PSKeepAliveClosure keep_alive(promotion_manager);
- PSEvacuateFollowersClosure evac_followers(promotion_manager);
ReferenceProcessorStats stats;
ReferenceProcessorPhaseTimes pt(&_gc_timer, reference_processor()->num_q());
if (reference_processor()->processing_is_mt()) {
@@ -441,6 +443,11 @@
}
{
+ GCTraceTime(Debug, gc, phases) tm("Weak Processing", &_gc_timer);
+ WeakProcessor::weak_oops_do(&_is_alive_closure, &keep_alive, &evac_followers);
+ }
+
+ {
GCTraceTime(Debug, gc, phases) tm("Scrub String Table", &_gc_timer);
// Unlink any dead interned Strings and process the remaining live ones.
PSScavengeRootsClosure root_closure(promotion_manager);
--- a/src/hotspot/share/gc/serial/defNewGeneration.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/serial/defNewGeneration.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -41,6 +41,7 @@
#include "gc/shared/space.inline.hpp"
#include "gc/shared/spaceDecorator.hpp"
#include "gc/shared/strongRootsScope.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "logging/log.hpp"
#include "memory/iterator.hpp"
#include "memory/resourceArea.hpp"
@@ -658,6 +659,8 @@
gc_tracer.report_tenuring_threshold(tenuring_threshold());
pt.print_all_references();
+ WeakProcessor::weak_oops_do(&is_alive, &keep_alive, &evacuate_followers);
+
if (!_promotion_failed) {
// Swap the survivor spaces.
eden()->clear(SpaceDecorator::Mangle);
--- a/src/hotspot/share/gc/serial/genMarkSweep.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/serial/genMarkSweep.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -43,6 +43,7 @@
#include "gc/shared/referencePolicy.hpp"
#include "gc/shared/space.hpp"
#include "gc/shared/strongRootsScope.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "oops/instanceRefKlass.hpp"
#include "oops/oop.inline.hpp"
#include "prims/jvmtiExport.hpp"
@@ -217,6 +218,11 @@
gc_tracer()->report_gc_reference_stats(stats);
}
+ {
+ GCTraceTime(Debug, gc, phases) tm_m("Weak Processing", gc_timer());
+ WeakProcessor::weak_oops_do(&is_alive, &keep_alive, &follow_stack_closure);
+ }
+
// This is the point where the entire marking should have completed.
assert(_marking_stack.is_empty(), "Marking should have completed");
--- a/src/hotspot/share/gc/shared/genCollectedHeap.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/shared/genCollectedHeap.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -42,6 +42,7 @@
#include "gc/shared/space.hpp"
#include "gc/shared/strongRootsScope.hpp"
#include "gc/shared/vmGCOperations.hpp"
+#include "gc/shared/weakProcessor.hpp"
#include "gc/shared/workgroup.hpp"
#include "memory/filemap.hpp"
#include "memory/resourceArea.hpp"
@@ -652,7 +653,7 @@
}
void GenCollectedHeap::gen_process_weak_roots(OopClosure* root_closure) {
- JNIHandles::weak_oops_do(root_closure);
+ WeakProcessor::oops_do(root_closure);
_young_gen->ref_processor()->weak_oops_do(root_closure);
_old_gen->ref_processor()->weak_oops_do(root_closure);
}
--- a/src/hotspot/share/gc/shared/referenceProcessor.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/shared/referenceProcessor.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -36,7 +36,6 @@
#include "memory/resourceArea.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/java.hpp"
-#include "runtime/jniHandles.hpp"
ReferencePolicy* ReferenceProcessor::_always_clear_soft_ref_policy = NULL;
ReferencePolicy* ReferenceProcessor::_default_soft_ref_policy = NULL;
@@ -245,51 +244,16 @@
is_alive, keep_alive, complete_gc, task_executor, phase_times);
}
- // Weak global JNI references. It would make more sense (semantically) to
- // traverse these simultaneously with the regular weak references above, but
- // that is not how the JDK1.2 specification is. See #4126360. Native code can
- // thus use JNI weak references to circumvent the phantom references and
- // resurrect a "post-mortem" object.
- {
- GCTraceTime(Debug, gc, ref) tt("JNI Weak Reference", phase_times->gc_timer());
- if (task_executor != NULL) {
- task_executor->set_single_threaded_mode();
- }
- process_phaseJNI(is_alive, keep_alive, complete_gc);
+ if (task_executor != NULL) {
+ // Record the work done by the parallel workers.
+ task_executor->set_single_threaded_mode();
}
phase_times->set_total_time_ms((os::elapsedTime() - start_time) * 1000);
- log_develop_trace(gc, ref)("JNI Weak Reference count: " SIZE_FORMAT, count_jni_refs());
-
return stats;
}
-#ifndef PRODUCT
-// Calculate the number of jni handles.
-size_t ReferenceProcessor::count_jni_refs() {
- class CountHandleClosure: public OopClosure {
- private:
- size_t _count;
- public:
- CountHandleClosure(): _count(0) {}
- void do_oop(oop* unused) { _count++; }
- void do_oop(narrowOop* unused) { ShouldNotReachHere(); }
- size_t count() { return _count; }
- };
- CountHandleClosure global_handle_count;
- JNIHandles::weak_oops_do(&global_handle_count);
- return global_handle_count.count();
-}
-#endif
-
-void ReferenceProcessor::process_phaseJNI(BoolObjectClosure* is_alive,
- OopClosure* keep_alive,
- VoidClosure* complete_gc) {
- JNIHandles::weak_oops_do(is_alive, keep_alive);
- complete_gc->do_void();
-}
-
void ReferenceProcessor::enqueue_discovered_references(AbstractRefProcTaskExecutor* task_executor,
ReferenceProcessorPhaseTimes* phase_times) {
// Enqueue references that are not made active again, and
--- a/src/hotspot/share/gc/shared/referenceProcessor.hpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/gc/shared/referenceProcessor.hpp Wed Oct 18 22:10:28 2017 +0000
@@ -246,10 +246,6 @@
AbstractRefProcTaskExecutor* task_executor,
ReferenceProcessorPhaseTimes* phase_times);
- void process_phaseJNI(BoolObjectClosure* is_alive,
- OopClosure* keep_alive,
- VoidClosure* complete_gc);
-
// Work methods used by the method process_discovered_reflist
// Phase1: keep alive all those referents that are otherwise
// dead but which must be kept alive by policy (and their closure).
@@ -341,9 +337,6 @@
void clear_discovered_references(DiscoveredList& refs_list);
- // Calculate the number of jni handles.
- size_t count_jni_refs();
-
void log_reflist_counts(DiscoveredList ref_lists[], uint active_length, size_t total_count) PRODUCT_RETURN;
// Balances reference queues.
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/suspendibleThreadSet.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/shared/suspendibleThreadSet.hpp"
+#include "runtime/mutexLocker.hpp"
+#include "runtime/semaphore.hpp"
+#include "runtime/thread.inline.hpp"
+
+uint SuspendibleThreadSet::_nthreads = 0;
+uint SuspendibleThreadSet::_nthreads_stopped = 0;
+bool SuspendibleThreadSet::_suspend_all = false;
+double SuspendibleThreadSet::_suspend_all_start = 0.0;
+
+static Semaphore* _synchronize_wakeup = NULL;
+
+void SuspendibleThreadSet_init() {
+ assert(_synchronize_wakeup == NULL, "STS already initialized");
+ _synchronize_wakeup = new Semaphore();
+}
+
+bool SuspendibleThreadSet::is_synchronized() {
+ assert_lock_strong(STS_lock);
+ assert(_nthreads_stopped <= _nthreads, "invariant");
+ return _nthreads_stopped == _nthreads;
+}
+
+void SuspendibleThreadSet::join() {
+ assert(!Thread::current()->is_suspendible_thread(), "Thread already joined");
+ MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
+ while (_suspend_all) {
+ ml.wait(Mutex::_no_safepoint_check_flag);
+ }
+ _nthreads++;
+ DEBUG_ONLY(Thread::current()->set_suspendible_thread();)
+}
+
+void SuspendibleThreadSet::leave() {
+ assert(Thread::current()->is_suspendible_thread(), "Thread not joined");
+ MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
+ assert(_nthreads > 0, "Invalid");
+ DEBUG_ONLY(Thread::current()->clear_suspendible_thread();)
+ _nthreads--;
+ if (_suspend_all && is_synchronized()) {
+ // This leave completes a request, so inform the requestor.
+ _synchronize_wakeup->signal();
+ }
+}
+
+void SuspendibleThreadSet::yield() {
+ assert(Thread::current()->is_suspendible_thread(), "Must have joined");
+ MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
+ if (_suspend_all) {
+ _nthreads_stopped++;
+ if (is_synchronized()) {
+ if (ConcGCYieldTimeout > 0) {
+ double now = os::elapsedTime();
+ guarantee((now - _suspend_all_start) * 1000.0 < (double)ConcGCYieldTimeout, "Long delay");
+ }
+ // This yield completes the request, so inform the requestor.
+ _synchronize_wakeup->signal();
+ }
+ while (_suspend_all) {
+ ml.wait(Mutex::_no_safepoint_check_flag);
+ }
+ assert(_nthreads_stopped > 0, "Invalid");
+ _nthreads_stopped--;
+ }
+}
+
+void SuspendibleThreadSet::synchronize() {
+ assert(Thread::current()->is_VM_thread(), "Must be the VM thread");
+ if (ConcGCYieldTimeout > 0) {
+ _suspend_all_start = os::elapsedTime();
+ }
+ {
+ MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
+ assert(!_suspend_all, "Only one at a time");
+ _suspend_all = true;
+ if (is_synchronized()) {
+ return;
+ }
+ } // Release lock before semaphore wait.
+
+ // Semaphore initial count is zero. To reach here, there must be at
+ // least one not yielded thread in the set, e.g. is_synchronized()
+ // was false before the lock was released. A thread in the set will
+ // signal the semaphore iff it is the last to yield or leave while
+ // there is an active suspend request. So there will be exactly one
+ // signal, which will increment the semaphore count to one, which
+ // will then be consumed by this wait, returning it to zero. No
+ // thread can exit yield or enter the set until desynchronize is
+ // called, so there are no further opportunities for the semaphore
+ // being signaled until we get back here again for some later
+ // synchronize call. Hence, there is no need to re-check for
+ // is_synchronized after the wait; it will always be true there.
+ _synchronize_wakeup->wait();
+
+#ifdef ASSERT
+ MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
+ assert(_suspend_all, "STS not synchronizing");
+ assert(is_synchronized(), "STS not synchronized");
+#endif
+}
+
+void SuspendibleThreadSet::desynchronize() {
+ assert(Thread::current()->is_VM_thread(), "Must be the VM thread");
+ MonitorLockerEx ml(STS_lock, Mutex::_no_safepoint_check_flag);
+ assert(_suspend_all, "STS not synchronizing");
+ assert(is_synchronized(), "STS not synchronized");
+ _suspend_all = false;
+ ml.notify_all();
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/suspendibleThreadSet.hpp Wed Oct 18 22:10:28 2017 +0000
@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_GC_SHARED_SUSPENDIBLETHREADSET_HPP
+#define SHARE_GC_SHARED_SUSPENDIBLETHREADSET_HPP
+
+#include "memory/allocation.hpp"
+
+// A SuspendibleThreadSet is a set of threads that can be suspended.
+// A thread can join and later leave the set, and periodically yield.
+// If some thread (not in the set) requests, via synchronize(), that
+// the threads be suspended, then the requesting thread is blocked
+// until all the threads in the set have yielded or left the set. Threads
+// may not enter the set when an attempted suspension is in progress. The
+// suspending thread later calls desynchronize(), allowing the suspended
+// threads to continue.
+class SuspendibleThreadSet : public AllStatic {
+ friend class SuspendibleThreadSetJoiner;
+ friend class SuspendibleThreadSetLeaver;
+
+private:
+ static uint _nthreads;
+ static uint _nthreads_stopped;
+ static bool _suspend_all;
+ static double _suspend_all_start;
+
+ static bool is_synchronized();
+
+ // Add the current thread to the set. May block if a suspension is in progress.
+ static void join();
+
+ // Removes the current thread from the set.
+ static void leave();
+
+public:
+ // Returns true if an suspension is in progress.
+ static bool should_yield() { return _suspend_all; }
+
+ // Suspends the current thread if a suspension is in progress.
+ static void yield();
+
+ // Returns when all threads in the set are suspended.
+ static void synchronize();
+
+ // Resumes all suspended threads in the set.
+ static void desynchronize();
+};
+
+class SuspendibleThreadSetJoiner : public StackObj {
+private:
+ bool _active;
+
+public:
+ SuspendibleThreadSetJoiner(bool active = true) : _active(active) {
+ if (_active) {
+ SuspendibleThreadSet::join();
+ }
+ }
+
+ ~SuspendibleThreadSetJoiner() {
+ if (_active) {
+ SuspendibleThreadSet::leave();
+ }
+ }
+
+ bool should_yield() {
+ if (_active) {
+ return SuspendibleThreadSet::should_yield();
+ } else {
+ return false;
+ }
+ }
+
+ void yield() {
+ assert(_active, "Thread has not joined the suspendible thread set");
+ SuspendibleThreadSet::yield();
+ }
+};
+
+class SuspendibleThreadSetLeaver : public StackObj {
+private:
+ bool _active;
+
+public:
+ SuspendibleThreadSetLeaver(bool active = true) : _active(active) {
+ if (_active) {
+ SuspendibleThreadSet::leave();
+ }
+ }
+
+ ~SuspendibleThreadSetLeaver() {
+ if (_active) {
+ SuspendibleThreadSet::join();
+ }
+ }
+};
+
+#endif // SHARE_GC_SHARED_SUSPENDIBLETHREADSET_HPP
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/weakProcessor.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/shared/weakProcessor.hpp"
+#include "prims/jvmtiExport.hpp"
+#include "runtime/jniHandles.hpp"
+
+void WeakProcessor::weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, VoidClosure* complete) {
+ JNIHandles::weak_oops_do(is_alive, keep_alive);
+ JvmtiExport::weak_oops_do(is_alive, keep_alive);
+
+ if (complete != NULL) {
+ complete->do_void();
+ }
+}
+
+void WeakProcessor::oops_do(OopClosure* closure) {
+ AlwaysTrueClosure always_true;
+ weak_oops_do(&always_true, closure, NULL);
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/weakProcessor.hpp Wed Oct 18 22:10:28 2017 +0000
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_GC_SHARED_WEAKPROCESSOR_HPP
+#define SHARE_VM_GC_SHARED_WEAKPROCESSOR_HPP
+
+#include "memory/allocation.hpp"
+#include "memory/iterator.hpp"
+
+// Helper class to aid in root scanning and cleaning of weak oops in the VM.
+//
+// New containers of weak oops added to this class will automatically
+// be cleaned by all GCs, including the young generation GCs.
+class WeakProcessor : AllStatic {
+public:
+ // Visit all oop*s and apply the keep_alive closure if the referenced
+ // object is considered alive by the is_alive closure, otherwise do some
+ // container specific cleanup of element holding the oop.
+ //
+ // The complete closure is used as a post-processing step,
+ // called after all container have been processed.
+ static void weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, VoidClosure* complete = NULL);
+
+ // Visit all oop*s and apply the given closure.
+ static void oops_do(OopClosure* closure);
+};
+
+#endif // SHARE_VM_GC_SHARED_WEAKPROCESSOR_HPP
--- a/src/hotspot/share/runtime/jniHandles.cpp Wed Oct 18 21:05:09 2017 +0000
+++ b/src/hotspot/share/runtime/jniHandles.cpp Wed Oct 18 22:10:28 2017 +0000
@@ -27,7 +27,6 @@
#include "logging/log.hpp"
#include "memory/iterator.hpp"
#include "oops/oop.inline.hpp"
-#include "prims/jvmtiExport.hpp"
#include "runtime/jniHandles.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/thread.inline.hpp"
@@ -424,12 +423,6 @@
break;
}
}
-
- /*
- * JVMTI data structures may also contain weak oops. The iteration of them
- * is placed here so that we don't need to add it to each of the collectors.
- */
- JvmtiExport::weak_oops_do(is_alive, f);
}