1 /*
2 * Copyright (c) 2012, 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
25 #ifndef SHARE_VM_JFR_RECORDER_SERVICE_JFREVENT_HPP
26 #define SHARE_VM_JFR_RECORDER_SERVICE_JFREVENT_HPP
27
28 #include "jfr/recorder/jfrEventSetting.inline.hpp"
29 #include "jfr/recorder/stacktrace/jfrStackTraceRepository.hpp"
30 #include "jfr/utilities/jfrTime.hpp"
31 #include "jfr/utilities/jfrTypes.hpp"
32 #include "jfr/writers/jfrNativeEventWriter.hpp"
33 #include "runtime/thread.hpp"
34 #include "utilities/exceptions.hpp"
35 #include "utilities/ticks.hpp"
36 #ifdef ASSERT
37 #include "utilities/bitMap.hpp"
38 #endif
39
40 #ifdef ASSERT
41 class JfrEventVerifier {
42 template <typename>
43 friend class JfrEvent;
44 private:
45 // verification of event fields
46 BitMap::bm_word_t _verification_storage[1];
47 BitMap _verification_bit_map;
48 bool _committed;
49
50 JfrEventVerifier();
51 void check(BitMap::idx_t field_idx) const;
52 void set_field_bit(size_t field_idx);
53 bool verify_field_bit(size_t field_idx) const;
54 void set_committed();
55 void clear_committed();
56 bool committed() const;
57 };
58 #endif // ASSERT
59
60 template <typename T>
61 class JfrEvent {
62 private:
63 jlong _start_time;
64 jlong _end_time;
65 bool _started;
66
67 protected:
68 JfrEvent(EventStartTime timing=TIMED) : _start_time(0), _end_time(0), _started(false)
69 #ifdef ASSERT
70 , _verifier()
71 #endif
72 {
73 if (T::is_enabled()) {
74 _started = true;
75 if (TIMED == timing && !T::isInstant) {
76 set_starttime(JfrTicks::now());
77 }
78 }
79 }
80
81 void commit() {
82 if (!should_commit()) {
83 return;
84 }
85 assert(!_verifier.committed(), "event already committed");
86 if (_start_time == 0) {
87 set_starttime(JfrTicks::now());
88 } else if (_end_time == 0) {
89 set_endtime(JfrTicks::now());
90 }
91 if (should_write()) {
92 write_event();
93 DEBUG_ONLY(_verifier.set_committed();)
94 }
95 }
96
97 public:
98 void set_starttime(const JfrTicks& time) {
99 _start_time = time.value();
100 }
101
102 void set_endtime(const JfrTicks& time) {
103 _end_time = time.value();
104 }
105
106 void set_starttime(const Ticks& time) {
107 _start_time = JfrTime::is_ft_enabled() ? time.ft_value() : time.value();
108 }
109
110 void set_endtime(const Ticks& time) {
111 _end_time = JfrTime::is_ft_enabled() ? time.ft_value() : time.value();
112 }
113
114 static bool is_enabled() {
115 return JfrEventSetting::is_enabled(T::eventId);
116 }
117
118 static bool is_stacktrace_enabled() {
119 return JfrEventSetting::has_stacktrace(T::eventId);
120 }
121
122 static JfrEventId id() {
123 return T::eventId;
124 }
125
126 static bool is_instant() {
127 return T::isInstant;
128 }
129
130 static bool is_requestable() {
131 return T::isRequestable;
132 }
133
134 static bool has_thread() {
135 return T::hasThread;
136 }
137
138 static bool has_stacktrace() {
139 return T::hasStackTrace;
140 }
141
142 bool should_commit() {
143 return _started;
144 }
145
146 private:
147 bool should_write() {
148 if (T::isInstant || T::isRequestable || T::hasCutoff) {
149 return true;
150 }
151 return (_end_time - _start_time) >= JfrEventSetting::threshold(T::eventId);
152 }
153
154 void write_event() {
155 DEBUG_ONLY(assert_precondition();)
156 Thread* const event_thread = Thread::current();
157 JfrThreadLocal* const tl = event_thread->jfr_thread_local();
158 JfrBuffer* const buffer = tl->native_buffer();
159 if (buffer == NULL) {
160 // most likely a pending OOM
161 return;
162 }
163 JfrNativeEventWriter writer(buffer, event_thread);
164 writer.write<u8>(T::eventId);
165 assert(_start_time != 0, "invariant");
166 writer.write(_start_time);
167 if (!(T::isInstant || T::isRequestable) || T::hasCutoff) {
168 assert(_end_time != 0, "invariant");
169 writer.write(_end_time - _start_time);
170 }
171 if (T::hasThread) {
172 writer.write(tl->thread_id());
173 }
174 if (T::hasStackTrace) {
175 if (is_stacktrace_enabled()) {
176 if (tl->has_cached_stack_trace()) {
177 writer.write(tl->cached_stack_trace_id());
178 } else {
179 writer.write(JfrStackTraceRepository::record(event_thread));
180 }
181 } else {
182 writer.write<traceid>(0);
183 }
184 }
185 // payload
186 static_cast<T*>(this)->writeData(writer);
187 }
188
189 #ifdef ASSERT
190 private:
191 // verification of event fields
192 JfrEventVerifier _verifier;
193
194 void assert_precondition() {
195 assert(T::eventId >= (JfrEventId)NUM_RESERVED_EVENTS, "event id underflow invariant");
196 assert(T::eventId < MaxJfrEventId, "event id overflow invariant");
197 DEBUG_ONLY(static_cast<T*>(this)->verify());
198 }
199
200 protected:
201 void set_field_bit(size_t field_idx) {
202 _verifier.set_field_bit(field_idx);
203 // it is ok to reuse an already committed event
204 // granted you provide new informational content
205 _verifier.clear_committed();
206 }
207
208 bool verify_field_bit(size_t field_idx) const {
209 return _verifier.verify_field_bit(field_idx);
210 }
211 #endif // ASSERT
212 };
213
214 #endif // SHARE_VM_JFR_RECORDER_SERVICE_JFREVENT_HPP