1 /*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #ifndef _LIBS_CUTILS_TRACE_H
18 #define _LIBS_CUTILS_TRACE_H
19
20 #include <sys/cdefs.h>
21 #include <sys/types.h>
22 #include <stdint.h>
23 #include <stdbool.h>
24 #include <unistd.h>
25 #include <cutils/compiler.h>
26
27 #ifdef ANDROID_SMP
28 #include <cutils/atomic-inline.h>
29 #else
30 #include <cutils/atomic.h>
31 #endif
32
33 __BEGIN_DECLS
34
35 /**
36 * The ATRACE_TAG macro can be defined before including this header to trace
37 * using one of the tags defined below. It must be defined to one of the
38 * following ATRACE_TAG_* macros. The trace tag is used to filter tracing in
39 * userland to avoid some of the runtime cost of tracing when it is not desired.
40 *
41 * Defining ATRACE_TAG to be ATRACE_TAG_ALWAYS will result in the tracing always
42 * being enabled - this should ONLY be done for debug code, as userland tracing
43 * has a performance cost even when the trace is not being recorded. Defining
44 * ATRACE_TAG to be ATRACE_TAG_NEVER or leaving ATRACE_TAG undefined will result
45 * in the tracing always being disabled.
46 *
47 * ATRACE_TAG_HAL should be bitwise ORed with the relevant tags for tracing
48 * within a hardware module. For example a camera hardware module would set:
49 * #define ATRACE_TAG (ATRACE_TAG_CAMERA | ATRACE_TAG_HAL)
50 *
51 * Keep these in sync with frameworks/base/core/java/android/os/Trace.java.
52 */
53 #define ATRACE_TAG_NEVER 0 // This tag is never enabled.
54 #define ATRACE_TAG_ALWAYS (1<<0) // This tag is always enabled.
55 #define ATRACE_TAG_GRAPHICS (1<<1)
56 #define ATRACE_TAG_INPUT (1<<2)
57 #define ATRACE_TAG_VIEW (1<<3)
58 #define ATRACE_TAG_WEBVIEW (1<<4)
59 #define ATRACE_TAG_WINDOW_MANAGER (1<<5)
60 #define ATRACE_TAG_ACTIVITY_MANAGER (1<<6)
61 #define ATRACE_TAG_SYNC_MANAGER (1<<7)
62 #define ATRACE_TAG_AUDIO (1<<8)
63 #define ATRACE_TAG_VIDEO (1<<9)
64 #define ATRACE_TAG_CAMERA (1<<10)
65 #define ATRACE_TAG_HAL (1<<11)
66 #define ATRACE_TAG_APP (1<<12)
67 #define ATRACE_TAG_RESOURCES (1<<13)
68 #define ATRACE_TAG_DALVIK (1<<14)
69 #define ATRACE_TAG_LAST ATRACE_TAG_DALVIK
70
71 // Reserved for initialization.
72 #define ATRACE_TAG_NOT_READY (1LL<<63)
73
74 #define ATRACE_TAG_VALID_MASK ((ATRACE_TAG_LAST - 1) | ATRACE_TAG_LAST)
75
76 #ifndef ATRACE_TAG
77 #define ATRACE_TAG ATRACE_TAG_NEVER
78 #elif ATRACE_TAG > ATRACE_TAG_VALID_MASK
79 #error ATRACE_TAG must be defined to be one of the tags defined in cutils/trace.h
80 #endif
81
82 #ifdef HAVE_ANDROID_OS
83 /**
84 * Maximum size of a message that can be logged to the trace buffer.
85 * Note this message includes a tag, the pid, and the string given as the name.
86 * Names should be kept short to get the most use of the trace buffer.
87 */
88 #define ATRACE_MESSAGE_LENGTH 1024
89
90 /**
91 * Opens the trace file for writing and reads the property for initial tags.
92 * The atrace.tags.enableflags property sets the tags to trace.
93 * This function should not be explicitly called, the first call to any normal
94 * trace function will cause it to be run safely.
95 */
96 void atrace_setup();
97
98 /**
99 * If tracing is ready, set atrace_enabled_tags to the system property
100 * debug.atrace.tags.enableflags. Can be used as a sysprop change callback.
101 */
102 void atrace_update_tags();
103
104 /**
105 * Set whether the process is debuggable. By default the process is not
106 * considered debuggable. If the process is not debuggable then application-
107 * level tracing is not allowed unless the ro.debuggable system property is
108 * set to '1'.
109 */
110 void atrace_set_debuggable(bool debuggable);
111
112 /**
113 * Set whether tracing is enabled for the current process. This is used to
114 * prevent tracing within the Zygote process.
115 */
116 void atrace_set_tracing_enabled(bool enabled);
117
118 /**
119 * Flag indicating whether setup has been completed, initialized to 0.
120 * Nonzero indicates setup has completed.
121 * Note: This does NOT indicate whether or not setup was successful.
122 */
123 extern volatile int32_t atrace_is_ready;
124
125 /**
126 * Set of ATRACE_TAG flags to trace for, initialized to ATRACE_TAG_NOT_READY.
127 * A value of zero indicates setup has failed.
128 * Any other nonzero value indicates setup has succeeded, and tracing is on.
129 */
130 extern uint64_t atrace_enabled_tags;
131
132 /**
133 * Handle to the kernel's trace buffer, initialized to -1.
134 * Any other value indicates setup has succeeded, and is a valid fd for tracing.
135 */
136 extern int atrace_marker_fd;
137
138 /**
139 * atrace_init readies the process for tracing by opening the trace_marker file.
140 * Calling any trace function causes this to be run, so calling it is optional.
141 * This can be explicitly run to avoid setup delay on first trace function.
142 */
143 #define ATRACE_INIT() atrace_init()
atrace_init()144 static inline void atrace_init()
145 {
146 if (CC_UNLIKELY(!android_atomic_acquire_load(&atrace_is_ready))) {
147 atrace_setup();
148 }
149 }
150
151 /**
152 * Get the mask of all tags currently enabled.
153 * It can be used as a guard condition around more expensive trace calculations.
154 * Every trace function calls this, which ensures atrace_init is run.
155 */
156 #define ATRACE_GET_ENABLED_TAGS() atrace_get_enabled_tags()
atrace_get_enabled_tags()157 static inline uint64_t atrace_get_enabled_tags()
158 {
159 atrace_init();
160 return atrace_enabled_tags;
161 }
162
163 /**
164 * Test if a given tag is currently enabled.
165 * Returns nonzero if the tag is enabled, otherwise zero.
166 * It can be used as a guard condition around more expensive trace calculations.
167 */
168 #define ATRACE_ENABLED() atrace_is_tag_enabled(ATRACE_TAG)
atrace_is_tag_enabled(uint64_t tag)169 static inline uint64_t atrace_is_tag_enabled(uint64_t tag)
170 {
171 return atrace_get_enabled_tags() & tag;
172 }
173
174 /**
175 * Trace the beginning of a context. name is used to identify the context.
176 * This is often used to time function execution.
177 */
178 #define ATRACE_BEGIN(name) atrace_begin(ATRACE_TAG, name)
atrace_begin(uint64_t tag,const char * name)179 static inline void atrace_begin(uint64_t tag, const char* name)
180 {
181 if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
182 char buf[ATRACE_MESSAGE_LENGTH];
183 size_t len;
184
185 len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "B|%d|%s", getpid(), name);
186 write(atrace_marker_fd, buf, len);
187 }
188 }
189
190 /**
191 * Trace the end of a context.
192 * This should match up (and occur after) a corresponding ATRACE_BEGIN.
193 */
194 #define ATRACE_END() atrace_end(ATRACE_TAG)
atrace_end(uint64_t tag)195 static inline void atrace_end(uint64_t tag)
196 {
197 if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
198 char c = 'E';
199 write(atrace_marker_fd, &c, 1);
200 }
201 }
202
203 /**
204 * Trace the beginning of an asynchronous event. Unlike ATRACE_BEGIN/ATRACE_END
205 * contexts, asynchronous events do not need to be nested. The name describes
206 * the event, and the cookie provides a unique identifier for distinguishing
207 * simultaneous events. The name and cookie used to begin an event must be
208 * used to end it.
209 */
210 #define ATRACE_ASYNC_BEGIN(name, cookie) \
211 atrace_async_begin(ATRACE_TAG, name, cookie)
atrace_async_begin(uint64_t tag,const char * name,int32_t cookie)212 static inline void atrace_async_begin(uint64_t tag, const char* name,
213 int32_t cookie)
214 {
215 if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
216 char buf[ATRACE_MESSAGE_LENGTH];
217 size_t len;
218
219 len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "S|%d|%s|%d", getpid(),
220 name, cookie);
221 write(atrace_marker_fd, buf, len);
222 }
223 }
224
225 /**
226 * Trace the end of an asynchronous event.
227 * This should have a corresponding ATRACE_ASYNC_BEGIN.
228 */
229 #define ATRACE_ASYNC_END(name, cookie) atrace_async_end(ATRACE_TAG, name, cookie)
atrace_async_end(uint64_t tag,const char * name,int32_t cookie)230 static inline void atrace_async_end(uint64_t tag, const char* name,
231 int32_t cookie)
232 {
233 if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
234 char buf[ATRACE_MESSAGE_LENGTH];
235 size_t len;
236
237 len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "F|%d|%s|%d", getpid(),
238 name, cookie);
239 write(atrace_marker_fd, buf, len);
240 }
241 }
242
243
244 /**
245 * Traces an integer counter value. name is used to identify the counter.
246 * This can be used to track how a value changes over time.
247 */
248 #define ATRACE_INT(name, value) atrace_int(ATRACE_TAG, name, value)
atrace_int(uint64_t tag,const char * name,int32_t value)249 static inline void atrace_int(uint64_t tag, const char* name, int32_t value)
250 {
251 if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
252 char buf[ATRACE_MESSAGE_LENGTH];
253 size_t len;
254
255 len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "C|%d|%s|%d",
256 getpid(), name, value);
257 write(atrace_marker_fd, buf, len);
258 }
259 }
260
261 #else // not HAVE_ANDROID_OS
262
263 #define ATRACE_INIT()
264 #define ATRACE_GET_ENABLED_TAGS()
265 #define ATRACE_ENABLED()
266 #define ATRACE_BEGIN(name)
267 #define ATRACE_END()
268 #define ATRACE_ASYNC_BEGIN(name, cookie)
269 #define ATRACE_ASYNC_END(name, cookie)
270 #define ATRACE_INT(name, value)
271
272 #endif // not HAVE_ANDROID_OS
273
274 __END_DECLS
275
276 #endif // _LIBS_CUTILS_TRACE_H
277