| /* |
| * Copyright (c) 2017, 2019, 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 "jfr/jfrEvents.hpp" |
| #include "jfr/leakprofiler/sampling/objectSample.hpp" |
| #include "jfr/leakprofiler/sampling/objectSampler.hpp" |
| #include "jfr/leakprofiler/sampling/sampleList.hpp" |
| #include "jfr/leakprofiler/sampling/samplePriorityQueue.hpp" |
| #include "jfr/recorder/jfrEventSetting.inline.hpp" |
| #include "jfr/recorder/checkpoint/jfrCheckpointManager.hpp" |
| #include "jfr/recorder/stacktrace/jfrStackTraceRepository.hpp" |
| #include "jfr/support/jfrThreadLocal.hpp" |
| #include "jfr/utilities/jfrTryLock.hpp" |
| #include "logging/log.hpp" |
| #include "memory/universe.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "runtime/atomic.hpp" |
| #include "runtime/orderAccess.hpp" |
| #include "runtime/safepoint.hpp" |
| #include "runtime/thread.hpp" |
| |
| static ObjectSampler* _instance = NULL; |
| |
| static ObjectSampler& instance() { |
| assert(_instance != NULL, "invariant"); |
| return *_instance; |
| } |
| |
| ObjectSampler::ObjectSampler(size_t size) : |
| _priority_queue(new SamplePriorityQueue(size)), |
| _list(new SampleList(size)), |
| _last_sweep(JfrTicks::now()), |
| _total_allocated(0), |
| _threshold(0), |
| _size(size), |
| _dead_samples(false) {} |
| |
| ObjectSampler::~ObjectSampler() { |
| delete _priority_queue; |
| _priority_queue = NULL; |
| delete _list; |
| _list = NULL; |
| } |
| |
| bool ObjectSampler::create(size_t size) { |
| assert(SafepointSynchronize::is_at_safepoint(), "invariant"); |
| assert(_instance == NULL, "invariant"); |
| _instance = new ObjectSampler(size); |
| return _instance != NULL; |
| } |
| |
| bool ObjectSampler::is_created() { |
| return _instance != NULL; |
| } |
| |
| ObjectSampler* ObjectSampler::sampler() { |
| assert(is_created(), "invariant"); |
| return _instance; |
| } |
| |
| void ObjectSampler::destroy() { |
| assert(SafepointSynchronize::is_at_safepoint(), "invariant"); |
| if (_instance != NULL) { |
| ObjectSampler* const sampler = _instance; |
| _instance = NULL; |
| delete sampler; |
| } |
| } |
| |
| static volatile int _lock = 0; |
| |
| ObjectSampler* ObjectSampler::acquire() { |
| assert(is_created(), "invariant"); |
| while (Atomic::cmpxchg(1, &_lock, 0) == 1) {} |
| return _instance; |
| } |
| |
| void ObjectSampler::release() { |
| assert(is_created(), "invariant"); |
| OrderAccess::fence(); |
| _lock = 0; |
| } |
| |
| static traceid get_thread_id(JavaThread* thread) { |
| assert(thread != NULL, "invariant"); |
| if (thread->threadObj() == NULL) { |
| return 0; |
| } |
| const JfrThreadLocal* const tl = thread->jfr_thread_local(); |
| assert(tl != NULL, "invariant"); |
| if (tl->is_excluded()) { |
| return 0; |
| } |
| if (!tl->has_thread_blob()) { |
| JfrCheckpointManager::create_thread_blob(thread); |
| } |
| assert(tl->has_thread_blob(), "invariant"); |
| return tl->thread_id(); |
| } |
| |
| static void record_stacktrace(JavaThread* thread) { |
| assert(thread != NULL, "invariant"); |
| if (JfrEventSetting::has_stacktrace(EventOldObjectSample::eventId)) { |
| JfrStackTraceRepository::record_and_cache(thread); |
| } |
| } |
| |
| void ObjectSampler::sample(HeapWord* obj, size_t allocated, JavaThread* thread) { |
| assert(thread != NULL, "invariant"); |
| assert(is_created(), "invariant"); |
| const traceid thread_id = get_thread_id(thread); |
| if (thread_id == 0) { |
| return; |
| } |
| record_stacktrace(thread); |
| // try enter critical section |
| JfrTryLock tryLock(&_lock); |
| if (!tryLock.has_lock()) { |
| log_trace(jfr, oldobject, sampling)("Skipping old object sample due to lock contention"); |
| return; |
| } |
| instance().add(obj, allocated, thread_id, thread); |
| } |
| |
| void ObjectSampler::add(HeapWord* obj, size_t allocated, traceid thread_id, JavaThread* thread) { |
| assert(obj != NULL, "invariant"); |
| assert(thread_id != 0, "invariant"); |
| assert(thread != NULL, "invariant"); |
| assert(thread->jfr_thread_local()->has_thread_blob(), "invariant"); |
| |
| if (_dead_samples) { |
| scavenge(); |
| assert(!_dead_samples, "invariant"); |
| } |
| |
| _total_allocated += allocated; |
| const size_t span = _total_allocated - _priority_queue->total(); |
| ObjectSample* sample; |
| if ((size_t)_priority_queue->count() == _size) { |
| assert(_list->count() == _size, "invariant"); |
| const ObjectSample* peek = _priority_queue->peek(); |
| if (peek->span() > span) { |
| // quick reject, will not fit |
| return; |
| } |
| sample = _list->reuse(_priority_queue->pop()); |
| } else { |
| sample = _list->get(); |
| } |
| |
| assert(sample != NULL, "invariant"); |
| sample->set_thread_id(thread_id); |
| |
| const JfrThreadLocal* const tl = thread->jfr_thread_local(); |
| sample->set_thread(tl->thread_blob()); |
| |
| const unsigned int stacktrace_hash = tl->cached_stack_trace_hash(); |
| if (stacktrace_hash != 0) { |
| sample->set_stack_trace_id(tl->cached_stack_trace_id()); |
| sample->set_stack_trace_hash(stacktrace_hash); |
| } |
| |
| sample->set_span(allocated); |
| sample->set_object((oop)obj); |
| sample->set_allocated(allocated); |
| sample->set_allocation_time(JfrTicks::now()); |
| sample->set_heap_used_at_last_gc(Universe::get_heap_used_at_last_gc()); |
| _priority_queue->push(sample); |
| } |
| |
| void ObjectSampler::scavenge() { |
| ObjectSample* current = _list->last(); |
| while (current != NULL) { |
| ObjectSample* next = current->next(); |
| if (current->is_dead()) { |
| remove_dead(current); |
| } |
| current = next; |
| } |
| _dead_samples = false; |
| } |
| |
| void ObjectSampler::remove_dead(ObjectSample* sample) { |
| assert(sample != NULL, "invariant"); |
| assert(sample->is_dead(), "invariant"); |
| ObjectSample* const previous = sample->prev(); |
| // push span on to previous |
| if (previous != NULL) { |
| _priority_queue->remove(previous); |
| previous->add_span(sample->span()); |
| _priority_queue->push(previous); |
| } |
| _priority_queue->remove(sample); |
| _list->release(sample); |
| } |
| |
| void ObjectSampler::oops_do(BoolObjectClosure* is_alive, OopClosure* f) { |
| assert(is_created(), "invariant"); |
| assert(SafepointSynchronize::is_at_safepoint(), "invariant"); |
| ObjectSampler& sampler = instance(); |
| ObjectSample* current = sampler._list->last(); |
| while (current != NULL) { |
| ObjectSample* next = current->next(); |
| if (!current->is_dead()) { |
| if (is_alive->do_object_b(current->object())) { |
| // The weakly referenced object is alive, update pointer |
| f->do_oop(const_cast<oop*>(current->object_addr())); |
| } else { |
| current->set_dead(); |
| sampler._dead_samples = true; |
| } |
| } |
| current = next; |
| } |
| sampler._last_sweep = JfrTicks::now(); |
| } |
| |
| ObjectSample* ObjectSampler::last() const { |
| return _list->last(); |
| } |
| |
| const ObjectSample* ObjectSampler::first() const { |
| return _list->first(); |
| } |
| |
| const ObjectSample* ObjectSampler::last_resolved() const { |
| return _list->last_resolved(); |
| } |
| |
| void ObjectSampler::set_last_resolved(const ObjectSample* sample) { |
| _list->set_last_resolved(sample); |
| } |
| |
| int ObjectSampler::item_count() const { |
| return _priority_queue->count(); |
| } |
| |
| const ObjectSample* ObjectSampler::item_at(int index) const { |
| return _priority_queue->item_at(index); |
| } |
| |
| ObjectSample* ObjectSampler::item_at(int index) { |
| return const_cast<ObjectSample*>( |
| const_cast<const ObjectSampler*>(this)->item_at(index) |
| ); |
| } |
| |
| const JfrTicks& ObjectSampler::last_sweep() const { |
| return _last_sweep; |
| } |