1 /*
2 * Copyright (c) 2014, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24 #include "precompiled.hpp"
25 #include "jfr/recorder/jfrEventSetting.hpp"
26 #include "jfr/recorder/access/jfrThreadData.hpp"
27 #include "jfr/recorder/checkpoint/jfrCheckpointManager.hpp"
28 #include "jfr/recorder/stacktrace/jfrStackTraceRepository.hpp"
29 #include "jfr/leakprofiler/sampling/objectSample.hpp"
30 #include "jfr/leakprofiler/sampling/objectSampler.hpp"
31 #include "jfr/leakprofiler/sampling/sampleList.hpp"
32 #include "jfr/leakprofiler/sampling/samplePriorityQueue.hpp"
33 #include "jfr/utilities/jfrTryLock.hpp"
34 #include "oops/oop.inline.hpp"
35 #include "runtime/thread.hpp"
36 #include "trace/tracing.hpp"
37
38 ObjectSampler::ObjectSampler(size_t size) :
39 _priority_queue(new SamplePriorityQueue(size)),
40 _list(new SampleList(size)),
41 _last_sweep(Tracing::time()),
42 _total_allocated(0),
43 _threshold(0),
44 _size(size),
45 _tryLock(0),
46 _dead_samples(false) {}
47
48 ObjectSampler::~ObjectSampler() {
49 delete _priority_queue;
50 _priority_queue = NULL;
51 delete _list;
52 _list = NULL;
53 }
54
55 void ObjectSampler::add(HeapWord* obj, size_t allocated, JavaThread* thread) {
56 assert(thread != NULL, "invariant");
57 const traceid thread_id = thread->threadObj() != NULL ? thread->trace_data()->thread_id() : 0;
58 if (thread_id == 0) {
59 return;
60 }
61 assert(thread_id != 0, "invariant");
62
63 if (!thread->trace_data()->has_thread_checkpoint()) {
64 JfrCheckpointManager::create_thread_checkpoint(thread);
65 assert(thread->trace_data()->has_thread_checkpoint(), "invariant");
66 }
67
68 traceid stack_trace_id = 0;
69 unsigned int stack_trace_hash = 0;
70 if (JfrEventSetting::has_stacktrace(EventOldObjectSample::eventId)) {
71 stack_trace_id = JfrStackTraceRepository::record(thread, 0, &stack_trace_hash);
72 thread->trace_data()->set_cached_stack_trace_id(stack_trace_id, stack_trace_hash);
73 }
74
75 const JfrTraceTime allocation_time = Tracing::time();
76
77 JfrTryLock tryLock(&_tryLock);
78 if (!tryLock.has_lock()) {
79 log_trace(jfr, oldobject, sampling)("Skipping old object sample due to lock contention");
80 return;
81 }
82
83 if (_dead_samples) {
84 scavenge();
85 assert(!_dead_samples, "invariant");
86 }
87
88 _total_allocated += allocated;
89 const size_t span = _total_allocated - _priority_queue->total();
90 ObjectSample* sample;
91 if ((size_t)_priority_queue->count() == _size) {
92 assert(_list->count() == _size, "invariant");
93 const ObjectSample* peek = _priority_queue->peek();
94 if (peek->span() > span) {
95 // quick reject, will not fit
96 return;
97 }
98 sample = _list->reuse(_priority_queue->pop());
99 } else {
100 sample = _list->get();
101 }
102
103 assert(sample != NULL, "invariant");
104 assert(thread_id != 0, "invariant");
105 sample->set_thread_id(thread_id);
106 sample->set_thread_checkpoint(thread->trace_data()->thread_checkpoint());
107
108 if (stack_trace_id != 0) {
109 sample->set_stack_trace_id(stack_trace_id);
110 sample->set_stack_trace_hash(stack_trace_hash);
111 }
112
113 sample->set_span(allocated);
114 sample->set_object((oop)obj);
115 sample->set_allocated(allocated);
116 sample->set_allocation_time(allocation_time);
117 _priority_queue->push(sample);
118 }
119
120 const ObjectSample* ObjectSampler::last() const {
121 return _list->last();
122 }
123
124 const ObjectSample* ObjectSampler::last_resolved() const {
125 return _list->last_resolved();
126 }
127
128 void ObjectSampler::set_last_resolved(const ObjectSample* sample) {
129 _list->set_last_resolved(sample);
130 }
131
132 void ObjectSampler::oops_do(BoolObjectClosure* is_alive, OopClosure* f) {
133 ObjectSample* current = _list->last();
134 while (current != NULL) {
135 ObjectSample* next = current->next();
136 if (!current->is_dead()) {
137 if (is_alive->do_object_b(current->object())) {
138 // The weakly referenced object is alive, update pointer
139 f->do_oop(const_cast<oop*>(current->object_addr()));
140 } else {
141 current->set_dead();
142 _dead_samples = true;
143 }
144 }
145 current = next;
146 }
147 _last_sweep = Tracing::time();
148 }
149
150 void ObjectSampler::remove_dead(ObjectSample* sample) {
151 assert(sample != NULL, "invariant");
152 assert(sample->is_dead(), "invariant");
153 ObjectSample* const previous = sample->prev();
154 // push span on to previous
155 if (previous != NULL) {
156 _priority_queue->remove(previous);
157 previous->add_span(sample->span());
158 _priority_queue->push(previous);
159 }
160 _priority_queue->remove(sample);
161 _list->release(sample);
162 }
163
164 void ObjectSampler::scavenge() {
165 ObjectSample* current = _list->last();
166 while (current != NULL) {
167 ObjectSample* next = current->next();
168 if (current->is_dead()) {
169 remove_dead(current);
170 }
171 current = next;
172 }
173 _dead_samples = false;
174 }
175
176 int ObjectSampler::item_count() const {
177 return _priority_queue->count();
178 }
179
180 const ObjectSample* ObjectSampler::item_at(int index) const {
181 return _priority_queue->item_at(index);
182 }
183
184 ObjectSample* ObjectSampler::item_at(int index) {
185 return const_cast<ObjectSample*>(
186 const_cast<const ObjectSampler*>(this)->item_at(index)
187 );
188 }
189
190 const JfrTraceTime& ObjectSampler::last_sweep() const {
191 return _last_sweep;
192 }