1 /* |
|
2 * Copyright (c) 2014, 2018, 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 "gc/shared/collectedHeap.hpp" |
|
26 #include "jfr/jfrEvents.hpp" |
|
27 #include "jfr/leakprofiler/utilities/granularTimer.hpp" |
|
28 #include "jfr/leakprofiler/chains/rootSetClosure.hpp" |
|
29 #include "jfr/leakprofiler/chains/edge.hpp" |
|
30 #include "jfr/leakprofiler/chains/edgeQueue.hpp" |
|
31 #include "jfr/leakprofiler/chains/edgeStore.hpp" |
|
32 #include "jfr/leakprofiler/chains/bitset.hpp" |
|
33 #include "jfr/leakprofiler/sampling/objectSample.hpp" |
|
34 #include "jfr/leakprofiler/leakProfiler.hpp" |
|
35 #include "jfr/leakprofiler/checkpoint/objectSampleCheckpoint.hpp" |
|
36 #include "jfr/leakprofiler/sampling/objectSampler.hpp" |
|
37 #include "jfr/leakprofiler/emitEventOperation.hpp" |
|
38 #include "jfr/leakprofiler/chains/bfsClosure.hpp" |
|
39 #include "jfr/leakprofiler/chains/dfsClosure.hpp" |
|
40 #include "jfr/leakprofiler/chains/objectSampleMarker.hpp" |
|
41 #include "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp" |
|
42 #include "jfr/support/jfrThreadId.hpp" |
|
43 #include "logging/log.hpp" |
|
44 #include "memory/resourceArea.hpp" |
|
45 #include "memory/universe.hpp" |
|
46 #include "oops/markOop.hpp" |
|
47 #include "oops/oop.inline.hpp" |
|
48 #include "runtime/safepoint.hpp" |
|
49 #include "runtime/vmThread.hpp" |
|
50 #include "utilities/globalDefinitions.hpp" |
|
51 |
|
52 /* The EdgeQueue is backed by directly managed virtual memory. |
|
53 * We will attempt to dimension an initial reservation |
|
54 * in proportion to the size of the heap (represented by heap_region). |
|
55 * Initial memory reservation: 5% of the heap OR at least 32 Mb |
|
56 * Commit ratio: 1 : 10 (subject to allocation granularties) |
|
57 */ |
|
58 static size_t edge_queue_memory_reservation(const MemRegion& heap_region) { |
|
59 const size_t memory_reservation_bytes = MAX2(heap_region.byte_size() / 20, 32*M); |
|
60 assert(memory_reservation_bytes >= (size_t)32*M, "invariant"); |
|
61 return memory_reservation_bytes; |
|
62 } |
|
63 |
|
64 static size_t edge_queue_memory_commit_size(size_t memory_reservation_bytes) { |
|
65 const size_t memory_commit_block_size_bytes = memory_reservation_bytes / 10; |
|
66 assert(memory_commit_block_size_bytes >= (size_t)3*M, "invariant"); |
|
67 return memory_commit_block_size_bytes; |
|
68 } |
|
69 |
|
70 static void log_edge_queue_summary(const EdgeQueue& edge_queue) { |
|
71 log_trace(jfr, system)("EdgeQueue reserved size total: " SIZE_FORMAT " [KB]", edge_queue.reserved_size() / K); |
|
72 log_trace(jfr, system)("EdgeQueue edges total: " SIZE_FORMAT, edge_queue.top()); |
|
73 log_trace(jfr, system)("EdgeQueue liveset total: " SIZE_FORMAT " [KB]", edge_queue.live_set() / K); |
|
74 if (edge_queue.reserved_size() > 0) { |
|
75 log_trace(jfr, system)("EdgeQueue commit reserve ratio: %f\n", |
|
76 ((double)edge_queue.live_set() / (double)edge_queue.reserved_size())); |
|
77 } |
|
78 } |
|
79 |
|
80 void EmitEventOperation::doit() { |
|
81 assert(LeakProfiler::is_running(), "invariant"); |
|
82 _object_sampler = LeakProfiler::object_sampler(); |
|
83 assert(_object_sampler != NULL, "invariant"); |
|
84 |
|
85 _vm_thread = VMThread::vm_thread(); |
|
86 assert(_vm_thread == Thread::current(), "invariant"); |
|
87 _vm_thread_local = _vm_thread->jfr_thread_local(); |
|
88 assert(_vm_thread_local != NULL, "invariant"); |
|
89 assert(_vm_thread->jfr_thread_local()->thread_id() == JFR_THREAD_ID(_vm_thread), "invariant"); |
|
90 |
|
91 // The VM_Operation::evaluate() which invoked doit() |
|
92 // contains a top level ResourceMark |
|
93 |
|
94 // save the original markWord for the potential leak objects |
|
95 // to be restored on function exit |
|
96 ObjectSampleMarker marker; |
|
97 if (ObjectSampleCheckpoint::mark(marker, _emit_all) == 0) { |
|
98 return; |
|
99 } |
|
100 |
|
101 EdgeStore edge_store; |
|
102 |
|
103 GranularTimer::start(_cutoff_ticks, 1000000); |
|
104 if (_cutoff_ticks <= 0) { |
|
105 // no chains |
|
106 write_events(&edge_store); |
|
107 return; |
|
108 } |
|
109 |
|
110 assert(_cutoff_ticks > 0, "invariant"); |
|
111 |
|
112 // The bitset used for marking is dimensioned as a function of the heap size |
|
113 const MemRegion heap_region = Universe::heap()->reserved_region(); |
|
114 BitSet mark_bits(heap_region); |
|
115 |
|
116 // The edge queue is dimensioned as a fraction of the heap size |
|
117 const size_t edge_queue_reservation_size = edge_queue_memory_reservation(heap_region); |
|
118 EdgeQueue edge_queue(edge_queue_reservation_size, edge_queue_memory_commit_size(edge_queue_reservation_size)); |
|
119 |
|
120 // The initialize() routines will attempt to reserve and allocate backing storage memory. |
|
121 // Failure to accommodate will render root chain processing impossible. |
|
122 // As a fallback on failure, just write out the existing samples, flat, without chains. |
|
123 if (!(mark_bits.initialize() && edge_queue.initialize())) { |
|
124 log_warning(jfr)("Unable to allocate memory for root chain processing"); |
|
125 write_events(&edge_store); |
|
126 return; |
|
127 } |
|
128 |
|
129 // necessary condition for attempting a root set iteration |
|
130 Universe::heap()->ensure_parsability(false); |
|
131 |
|
132 RootSetClosure::add_to_queue(&edge_queue); |
|
133 if (edge_queue.is_full()) { |
|
134 // Pathological case where roots don't fit in queue |
|
135 // Do a depth-first search, but mark roots first |
|
136 // to avoid walking sideways over roots |
|
137 DFSClosure::find_leaks_from_root_set(&edge_store, &mark_bits); |
|
138 } else { |
|
139 BFSClosure bfs(&edge_queue, &edge_store, &mark_bits); |
|
140 bfs.process(); |
|
141 } |
|
142 GranularTimer::stop(); |
|
143 write_events(&edge_store); |
|
144 log_edge_queue_summary(edge_queue); |
|
145 } |
|
146 |
|
147 int EmitEventOperation::write_events(EdgeStore* edge_store) { |
|
148 assert(_object_sampler != NULL, "invariant"); |
|
149 assert(edge_store != NULL, "invariant"); |
|
150 assert(_vm_thread != NULL, "invariant"); |
|
151 assert(_vm_thread_local != NULL, "invariant"); |
|
152 assert(SafepointSynchronize::is_at_safepoint(), "invariant"); |
|
153 |
|
154 // save thread id in preparation for thread local trace data manipulations |
|
155 const traceid vmthread_id = _vm_thread_local->thread_id(); |
|
156 assert(_vm_thread_local->thread_id() == JFR_THREAD_ID(_vm_thread), "invariant"); |
|
157 |
|
158 const jlong last_sweep = _emit_all ? max_jlong : _object_sampler->last_sweep().value(); |
|
159 int count = 0; |
|
160 |
|
161 const ObjectSample* current = _object_sampler->first(); |
|
162 while (current != NULL) { |
|
163 ObjectSample* prev = current->prev(); |
|
164 if (current->is_alive_and_older_than(last_sweep)) { |
|
165 write_event(current, edge_store); |
|
166 ++count; |
|
167 } |
|
168 current = prev; |
|
169 } |
|
170 |
|
171 // restore thread local stack trace and thread id |
|
172 _vm_thread_local->set_thread_id(vmthread_id); |
|
173 _vm_thread_local->clear_cached_stack_trace(); |
|
174 assert(_vm_thread_local->thread_id() == JFR_THREAD_ID(_vm_thread), "invariant"); |
|
175 |
|
176 if (count > 0) { |
|
177 // serialize assoicated checkpoints |
|
178 ObjectSampleCheckpoint::write(edge_store, _emit_all, _vm_thread); |
|
179 } |
|
180 return count; |
|
181 } |
|
182 |
|
183 static int array_size(const oop object) { |
|
184 assert(object != NULL, "invariant"); |
|
185 if (object->is_array()) { |
|
186 return arrayOop(object)->length(); |
|
187 } |
|
188 return min_jint; |
|
189 } |
|
190 |
|
191 void EmitEventOperation::write_event(const ObjectSample* sample, EdgeStore* edge_store) { |
|
192 assert(sample != NULL, "invariant"); |
|
193 assert(!sample->is_dead(), "invariant"); |
|
194 assert(edge_store != NULL, "invariant"); |
|
195 assert(_vm_thread_local != NULL, "invariant"); |
|
196 const oop* object_addr = sample->object_addr(); |
|
197 assert(*object_addr != NULL, "invariant"); |
|
198 |
|
199 const Edge* edge = (const Edge*)(*object_addr)->mark(); |
|
200 traceid gc_root_id = 0; |
|
201 if (edge == NULL) { |
|
202 // In order to dump out a representation of the event |
|
203 // even though it was not reachable / too long to reach, |
|
204 // we need to register a top level edge for this object |
|
205 Edge e(NULL, object_addr); |
|
206 edge_store->add_chain(&e, 1); |
|
207 edge = (const Edge*)(*object_addr)->mark(); |
|
208 } else { |
|
209 gc_root_id = edge_store->get_root_id(edge); |
|
210 } |
|
211 |
|
212 assert(edge != NULL, "invariant"); |
|
213 assert(edge->pointee() == *object_addr, "invariant"); |
|
214 const traceid object_id = edge_store->get_id(edge); |
|
215 assert(object_id != 0, "invariant"); |
|
216 |
|
217 EventOldObjectSample e(UNTIMED); |
|
218 e.set_starttime(GranularTimer::start_time()); |
|
219 e.set_endtime(GranularTimer::end_time()); |
|
220 e.set_allocationTime(sample->allocation_time()); |
|
221 e.set_lastKnownHeapUsage(sample->heap_used_at_last_gc()); |
|
222 e.set_object(object_id); |
|
223 e.set_arrayElements(array_size(*object_addr)); |
|
224 e.set_root(gc_root_id); |
|
225 |
|
226 // Temporarily assigning both the stack trace id and thread id |
|
227 // onto the thread local data structure of the VMThread (for the duration |
|
228 // of the commit() call). This trick provides a means to override |
|
229 // the event generation mechanism by injecting externally provided id's. |
|
230 // Here, in particular, this allows us to emit an old object event |
|
231 // supplying information from where the actual sampling occurred. |
|
232 _vm_thread_local->set_cached_stack_trace_id(sample->stack_trace_id()); |
|
233 assert(sample->has_thread(), "invariant"); |
|
234 _vm_thread_local->set_thread_id(sample->thread_id()); |
|
235 e.commit(); |
|
236 } |
|