1 /*
2 * Copyright (c) 2014, 2015, Dynatrace and/or its affiliates. All rights reserved.
3 *
4 * This file is part of the Lock Contention Tracing Subsystem for the HotSpot
5 * Virtual Machine, which is developed at Christian Doppler Laboratory on
6 * Monitoring and Evolution of Very-Large-Scale Software Systems. Please
7 * contact us at <http://mevss.jku.at/> if you need additional information
8 * or have any questions.
9 *
10 * This code is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License version 2 only, as
12 * published by the Free Software Foundation.
13 *
14 * This code is distributed in the hope that it will be useful, but WITHOUT
15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 * version 2 for more details (a copy is included in the LICENSE file that
18 * accompanied this code).
19 *
20 * You should have received a copy of the GNU General Public License version
21 * 2 along with this work. If not, see <http://www.gnu.org/licenses/>.
22 *
23 */
24
25 #ifndef SHARE_VM_EVTRACE_TRACESTACK_HPP
26 #define SHARE_VM_EVTRACE_TRACESTACK_HPP
27
28 #include "evtrace/traceTypes.hpp"
29
30 #include "memory/allocation.hpp"
31 #include "runtime/timer.hpp"
32
33 class Method;
34 class CachedTraceStack;
35 class TraceMetadata;
36
37 #define TRACE_STACK_MAX_FRAMES 128
38
39 class CompositeTraceStack;
40
41 struct TraceStackFrame {
42 bool is_compiled;
43 union {
44 struct {
45 nmethod *nm;
46 address pc;
47 } compiled;
48 struct {
49 Method *method;
50 int bci;
51 } interpreted;
52 };
53
54 intptr_t hash() const;
55 bool equals(const TraceStackFrame& other) const;
56 };
57
58 class TraceStackBuilder: StackObj {
59 private:
60 TraceStackFrame _frames[TRACE_STACK_MAX_FRAMES];
61 size_t _count;
62 bool _truncated;
63 intptr_t _hash;
64
65 void add(const TraceStackFrame &f);
66
67 public:
68 TraceStackBuilder();
69
70 void add_frame(const frame *fr);
71 void set_truncated() { _truncated = true; }
72
73 const TraceStackFrame *frame_at(size_t index) const;
74
75 size_t count() const { return _count; }
76 bool is_full() const { return (_count == EventTracingStackDepthLimit); }
77 bool is_truncated() const { return _truncated; }
78 intptr_t hash() const { return _hash; }
79
80 bool range_equals(size_t offset, const CachedTraceStack *cts, size_t cts_offset, size_t count) const;
81 };
82
83 class CachedTraceStack: CHeapObj<mtEventTracing> {
84 public:
85 static CachedTraceStack *create(TraceTypes::stack_id id, const CompositeTraceStack &ts);
86
87 const TraceStackFrame *frame_at(size_t index) const;
88
89 TraceTypes::stack_id id() const { return _id; }
90 size_t count() const { return _count; }
91 bool is_truncated() const { return _truncated; }
92 intptr_t hash() const { return _hash; }
93
94 bool has_interpreted_method_from_classloader(const ClassLoaderData *loader) const;
95 bool has_nmethod(const nmethod *nm) const;
96 bool range_equals(size_t offset, const CachedTraceStack *other, size_t other_offset, size_t count) const;
97
98 bool is_valid() const { return _valid; }
99 void invalidate();
100
101 CachedTraceStack *cache_next();
102 void set_cache_next(CachedTraceStack *next);
103
104 void operator delete(void* p);
105
106 private:
107 void* operator new(size_t size, size_t nframes) throw ();
108 CachedTraceStack(TraceTypes::stack_id id, const CompositeTraceStack &ts);
109
110 CachedTraceStack * volatile _cache_next;
111
112 const TraceTypes::stack_id _id;
113 const intptr_t _hash;
114 const size_t _count;
115 const bool _truncated;
116 bool _valid;
117 TraceStackFrame _frames[0];
118 };
119
120 class CompositeTraceStack: StackObj {
121 private:
122 const TraceStackBuilder &_top;
123 const CachedTraceStack *_bottom;
124 size_t _bottom_offset;
125 intptr_t _hash;
126 size_t _count;
127 bool _truncated;
128
129 public:
130 CompositeTraceStack(TraceStackBuilder &top);
131
132 void set_bottom(const CachedTraceStack *cts, size_t offset);
133
134 bool equals(const CachedTraceStack *cts) const;
135 bool equals(const CompositeTraceStack &other) const;
136
137 const TraceStackFrame *frame_at(size_t index) const;
138
139 intptr_t hash() const { return _hash; }
140 size_t count() const { return _count; }
141 bool is_truncated() const { return _truncated; }
142 };
143
144 class TraceStackVframeIterator: StackObj {
145 private:
146 const CompositeTraceStack &_ts;
147 int _index;
148 int _decode_offset;
149 Method *_method;
150 int _bci;
151
152 void fill_from_compiled_frame();
153
154 public:
155 TraceStackVframeIterator(const CompositeTraceStack &ts);
156
157 bool has_next();
158 void next();
159 void reset();
160
161 Method *method() { return _method; }
162 int bci() { return _bci; }
163 };
164
165 class TraceStackCache: public CHeapObj<mtEventTracing> {
166 private:
167 TraceMetadata *_metadata;
168
169 CachedTraceStack **_table;
170 volatile intptr_t _count;
171 size_t _size;
172 volatile bool _has_invalid_stacks;
173
174 // statistics
175 elapsedTimer _purge_timer;
176 elapsedTimer _maintenance_timer;
177 volatile intptr_t _lookup_counter;
178 volatile intptr_t _lookup_miss_counter;
179 volatile intptr_t _lookup_collision_counter;
180 volatile intptr_t _probe_counter;
181 volatile intptr_t _probe_collision_counter;
182
183 void add_for_rehash(CachedTraceStack *cts);
184
185 class CachedTraceStackPredicate;
186 class UnloadingClassPredicate;
187 class UnloadingNmethodPredicate;
188 class AnyPredicate;
189 void purge_matches(CachedTraceStackPredicate *pr);
190
191 void update_counters_after_lookup(bool present, jlong probes, jlong collisions);
192
193 public:
194 TraceStackCache(TraceMetadata *tm);
195 virtual ~TraceStackCache();
196
197 const CachedTraceStack * get_or_try_add(const CompositeTraceStack &ts, bool &known, TraceTypes::stack_id preallocated_id = 0);
198
199 void purge_unloading_classes(const ClassLoaderData *loader);
200 void purge_unloading_nmethod(const nmethod *nm);
201 void purge_all();
202
203 bool has_invalid_stacks() const { return _has_invalid_stacks; }
204 void do_maintenance();
205
206 intptr_t lookups() { return _lookup_counter; }
207 intptr_t lookup_misses() { return _lookup_miss_counter; }
208 intptr_t lookup_collisions() { return _lookup_collision_counter; }
209 intptr_t probes() { return _probe_counter; }
210 intptr_t probe_collisions() { return _probe_collision_counter; }
211 jlong purge_millis() { return _purge_timer.milliseconds(); }
212 jlong maintenance_millis() { return _maintenance_timer.milliseconds(); }
213 void reset_stats();
214 };
215
216 #include "evtrace/traceStack.inline.hpp"
217
218 #endif /* SHARE_VM_EVTRACE_TRACESTACK_HPP */