/*
* Copyright (c) 2015, 2019, Red Hat, Inc. All rights reserved.
*
* 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 "classfile/classLoaderDataGraph.hpp"
#include "classfile/stringTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "code/codeCache.hpp"
#include "gc/shenandoah/shenandoahRootProcessor.hpp"
#include "gc/shenandoah/shenandoahHeap.hpp"
#include "gc/shenandoah/shenandoahPhaseTimings.hpp"
#include "gc/shenandoah/shenandoahStringDedup.hpp"
#include "gc/shenandoah/shenandoahTimingTracker.hpp"
#include "gc/shenandoah/shenandoahUtils.hpp"
#include "gc/shenandoah/shenandoahVMOperations.hpp"
#include "gc/shared/weakProcessor.inline.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/iterator.hpp"
#include "memory/resourceArea.hpp"
#include "runtime/thread.hpp"
#include "services/management.hpp"
struct PhaseMap {
WeakProcessorPhases::Phase _weak_processor_phase;
ShenandoahPhaseTimings::GCParPhases _shenandoah_phase;
};
static const struct PhaseMap phase_mapping[] = {
#if INCLUDE_JVMTI
{WeakProcessorPhases::jvmti, ShenandoahPhaseTimings::JVMTIWeakRoots},
#endif
#if INCLUDE_JFR
{WeakProcessorPhases::jfr, ShenandoahPhaseTimings::JFRWeakRoots},
#endif
{WeakProcessorPhases::jni, ShenandoahPhaseTimings::JNIWeakRoots},
{WeakProcessorPhases::stringtable, ShenandoahPhaseTimings::StringTableRoots},
{WeakProcessorPhases::vm, ShenandoahPhaseTimings::VMWeakRoots}
};
STATIC_ASSERT(sizeof(phase_mapping) / sizeof(PhaseMap) == WeakProcessorPhases::phase_count);
ShenandoahRootProcessor::ShenandoahRootProcessor(ShenandoahHeap* heap, uint n_workers,
ShenandoahPhaseTimings::Phase phase) :
_process_strong_tasks(new SubTasksDone(SHENANDOAH_RP_PS_NumElements)),
_srs(n_workers),
_par_state_string(StringTable::weak_storage()),
_phase(phase),
_coderoots_all_iterator(ShenandoahCodeRoots::iterator()),
_weak_processor_timings(n_workers),
_weak_processor_task(&_weak_processor_timings, n_workers),
_processed_weak_roots(false) {
heap->phase_timings()->record_workers_start(_phase);
if (ShenandoahStringDedup::is_enabled()) {
StringDedup::gc_prologue(false);
}
}
ShenandoahRootProcessor::~ShenandoahRootProcessor() {
delete _process_strong_tasks;
if (ShenandoahStringDedup::is_enabled()) {
StringDedup::gc_epilogue();
}
ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
if (_processed_weak_roots) {
assert(_weak_processor_timings.max_threads() == n_workers(), "Must match");
for (uint index = 0; index < WeakProcessorPhases::phase_count; index ++) {
weak_processor_timing_to_shenandoah_timing(phase_mapping[index]._weak_processor_phase,
phase_mapping[index]._shenandoah_phase,
worker_times);
}
}
ShenandoahHeap::heap()->phase_timings()->record_workers_end(_phase);
}
void ShenandoahRootProcessor::weak_processor_timing_to_shenandoah_timing(const WeakProcessorPhases::Phase wpp,
const ShenandoahPhaseTimings::GCParPhases spp,
ShenandoahWorkerTimings* worker_times) const {
if (WeakProcessorPhases::is_serial(wpp)) {
worker_times->record_time_secs(spp, 0, _weak_processor_timings.phase_time_sec(wpp));
} else {
for (uint index = 0; index < _weak_processor_timings.max_threads(); index ++) {
worker_times->record_time_secs(spp, index, _weak_processor_timings.worker_time_sec(index, wpp));
}
}
}
void ShenandoahRootProcessor::process_all_roots_slow(OopClosure* oops) {
CLDToOopClosure clds(oops, ClassLoaderData::_claim_strong);
CodeBlobToOopClosure blobs(oops, !CodeBlobToOopClosure::FixRelocations);
CodeCache::blobs_do(&blobs);
ClassLoaderDataGraph::cld_do(&clds);
Universe::oops_do(oops);
Management::oops_do(oops);
JvmtiExport::oops_do(oops);
JNIHandles::oops_do(oops);
ObjectSynchronizer::oops_do(oops);
SystemDictionary::oops_do(oops);
// Do thread roots the last. This allows verification code to find
// any broken objects from those special roots first, not the accidental
// dangling reference from the thread root.
Threads::possibly_parallel_oops_do(false, oops, &blobs);
}
void ShenandoahRootProcessor::process_strong_roots(OopClosure* oops,
CLDClosure* clds,
CodeBlobClosure* blobs,
ThreadClosure* thread_cl,
uint worker_id) {
process_java_roots(oops, clds, NULL, blobs, thread_cl, worker_id);
process_vm_roots(oops, worker_id);
_process_strong_tasks->all_tasks_completed(n_workers());
}
void ShenandoahRootProcessor::process_all_roots(OopClosure* oops,
CLDClosure* clds,
CodeBlobClosure* blobs,
ThreadClosure* thread_cl,
uint worker_id) {
ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
process_java_roots(oops, clds, clds, blobs, thread_cl, worker_id);
process_vm_roots(oops, worker_id);
if (blobs != NULL) {
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::CodeCacheRoots, worker_id);
_coderoots_all_iterator.possibly_parallel_blobs_do(blobs);
}
_process_strong_tasks->all_tasks_completed(n_workers());
}
class ShenandoahParallelOopsDoThreadClosure : public ThreadClosure {
private:
OopClosure* _f;
CodeBlobClosure* _cf;
ThreadClosure* _thread_cl;
public:
ShenandoahParallelOopsDoThreadClosure(OopClosure* f, CodeBlobClosure* cf, ThreadClosure* thread_cl) :
_f(f), _cf(cf), _thread_cl(thread_cl) {}
void do_thread(Thread* t) {
if (_thread_cl != NULL) {
_thread_cl->do_thread(t);
}
t->oops_do(_f, _cf);
}
};
void ShenandoahRootProcessor::process_java_roots(OopClosure* strong_roots,
CLDClosure* strong_clds,
CLDClosure* weak_clds,
CodeBlobClosure* strong_code,
ThreadClosure* thread_cl,
uint worker_id)
{
ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
// Iterating over the CLDG and the Threads are done early to allow us to
// first process the strong CLDs and nmethods and then, after a barrier,
// let the thread process the weak CLDs and nmethods.
{
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::CLDGRoots, worker_id);
_cld_iterator.root_cld_do(strong_clds, weak_clds);
}
{
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::ThreadRoots, worker_id);
bool is_par = n_workers() > 1;
ResourceMark rm;
ShenandoahParallelOopsDoThreadClosure cl(strong_roots, strong_code, thread_cl);
Threads::possibly_parallel_threads_do(is_par, &cl);
}
}
void ShenandoahRootProcessor::process_vm_roots(OopClosure* strong_roots,
uint worker_id) {
ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
if (_process_strong_tasks->try_claim_task(SHENANDOAH_RP_PS_Universe_oops_do)) {
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::UniverseRoots, worker_id);
Universe::oops_do(strong_roots);
}
if (_process_strong_tasks->try_claim_task(SHENANDOAH_RP_PS_JNIHandles_oops_do)) {
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::JNIRoots, worker_id);
JNIHandles::oops_do(strong_roots);
}
if (_process_strong_tasks->try_claim_task(SHENANDOAH_RP_PS_Management_oops_do)) {
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::ManagementRoots, worker_id);
Management::oops_do(strong_roots);
}
if (_process_strong_tasks->try_claim_task(SHENANDOAH_RP_PS_jvmti_oops_do)) {
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::JVMTIRoots, worker_id);
JvmtiExport::oops_do(strong_roots);
}
if (_process_strong_tasks->try_claim_task(SHENANDOAH_RP_PS_SystemDictionary_oops_do)) {
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::SystemDictionaryRoots, worker_id);
SystemDictionary::oops_do(strong_roots);
}
{
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::ObjectSynchronizerRoots, worker_id);
if (_process_strong_tasks->try_claim_task(SHENANDOAH_RP_PS_ObjectSynchronizer_oops_do)) {
ObjectSynchronizer::oops_do(strong_roots);
}
}
}
uint ShenandoahRootProcessor::n_workers() const {
return _srs.n_threads();
}
ShenandoahRootEvacuator::ShenandoahRootEvacuator(ShenandoahHeap* heap, uint n_workers, ShenandoahPhaseTimings::Phase phase) :
_evacuation_tasks(new SubTasksDone(SHENANDOAH_EVAC_NumElements)),
_srs(n_workers),
_phase(phase),
_coderoots_cset_iterator(ShenandoahCodeRoots::cset_iterator())
{
heap->phase_timings()->record_workers_start(_phase);
}
ShenandoahRootEvacuator::~ShenandoahRootEvacuator() {
delete _evacuation_tasks;
ShenandoahHeap::heap()->phase_timings()->record_workers_end(_phase);
}
void ShenandoahRootEvacuator::process_evacuate_roots(OopClosure* oops,
CodeBlobClosure* blobs,
uint worker_id) {
ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
{
bool is_par = n_workers() > 1;
ResourceMark rm;
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::ThreadRoots, worker_id);
Threads::possibly_parallel_oops_do(is_par, oops, NULL);
}
if (blobs != NULL) {
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::CodeCacheRoots, worker_id);
_coderoots_cset_iterator.possibly_parallel_blobs_do(blobs);
}
if (_evacuation_tasks->try_claim_task(SHENANDOAH_EVAC_jvmti_oops_do)) {
ShenandoahForwardedIsAliveClosure is_alive;
ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::JVMTIRoots, worker_id);
JvmtiExport::weak_oops_do(&is_alive, oops);
}
}
uint ShenandoahRootEvacuator::n_workers() const {
return _srs.n_threads();
}
// Implemenation of ParallelCLDRootIterator
ParallelCLDRootIterator::ParallelCLDRootIterator() {
assert(SafepointSynchronize::is_at_safepoint(), "Must at safepoint");
ClassLoaderDataGraph::clear_claimed_marks();
}
void ParallelCLDRootIterator::root_cld_do(CLDClosure* strong, CLDClosure* weak) {
ClassLoaderDataGraph::roots_cld_do(strong, weak);
}