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 <inttypes.h>
21 #include <stdatomic.h>
22 #include <stdbool.h>
23 #include <stdint.h>
24 #include <stdio.h>
25 #include <sys/cdefs.h>
26 #include <sys/types.h>
27 #include <unistd.h>
28 #include <cutils/compiler.h>
29 
30 __BEGIN_DECLS
31 
32 /**
33  * The ATRACE_TAG macro can be defined before including this header to trace
34  * using one of the tags defined below.  It must be defined to one of the
35  * following ATRACE_TAG_* macros.  The trace tag is used to filter tracing in
36  * userland to avoid some of the runtime cost of tracing when it is not desired.
37  *
38  * Defining ATRACE_TAG to be ATRACE_TAG_ALWAYS will result in the tracing always
39  * being enabled - this should ONLY be done for debug code, as userland tracing
40  * has a performance cost even when the trace is not being recorded.  Defining
41  * ATRACE_TAG to be ATRACE_TAG_NEVER or leaving ATRACE_TAG undefined will result
42  * in the tracing always being disabled.
43  *
44  * ATRACE_TAG_HAL should be bitwise ORed with the relevant tags for tracing
45  * within a hardware module.  For example a camera hardware module would set:
46  * #define ATRACE_TAG  (ATRACE_TAG_CAMERA | ATRACE_TAG_HAL)
47  *
48  * Keep these in sync with frameworks/base/core/java/android/os/Trace.java.
49  */
50 #define ATRACE_TAG_NEVER            0       // This tag is never enabled.
51 #define ATRACE_TAG_ALWAYS           (1<<0)  // This tag is always enabled.
52 #define ATRACE_TAG_GRAPHICS         (1<<1)
53 #define ATRACE_TAG_INPUT            (1<<2)
54 #define ATRACE_TAG_VIEW             (1<<3)
55 #define ATRACE_TAG_WEBVIEW          (1<<4)
56 #define ATRACE_TAG_WINDOW_MANAGER   (1<<5)
57 #define ATRACE_TAG_ACTIVITY_MANAGER (1<<6)
58 #define ATRACE_TAG_SYNC_MANAGER     (1<<7)
59 #define ATRACE_TAG_AUDIO            (1<<8)
60 #define ATRACE_TAG_VIDEO            (1<<9)
61 #define ATRACE_TAG_CAMERA           (1<<10)
62 #define ATRACE_TAG_HAL              (1<<11)
63 #define ATRACE_TAG_APP              (1<<12)
64 #define ATRACE_TAG_RESOURCES        (1<<13)
65 #define ATRACE_TAG_DALVIK           (1<<14)
66 #define ATRACE_TAG_RS               (1<<15)
67 #define ATRACE_TAG_BIONIC           (1<<16)
68 #define ATRACE_TAG_POWER            (1<<17)
69 #define ATRACE_TAG_PACKAGE_MANAGER  (1<<18)
70 #define ATRACE_TAG_SYSTEM_SERVER    (1<<19)
71 #define ATRACE_TAG_DATABASE         (1<<20)
72 #define ATRACE_TAG_NETWORK          (1<<21)
73 #define ATRACE_TAG_ADB              (1<<22)
74 #define ATRACE_TAG_VIBRATOR         (1<<23)
75 #define ATRACE_TAG_AIDL             (1<<24)
76 #define ATRACE_TAG_NNAPI            (1<<25)
77 #define ATRACE_TAG_RRO              (1<<26)
78 #define ATRACE_TAG_LAST             ATRACE_TAG_RRO
79 
80 // Reserved for initialization.
81 #define ATRACE_TAG_NOT_READY        (1ULL<<63)
82 
83 #define ATRACE_TAG_VALID_MASK ((ATRACE_TAG_LAST - 1) | ATRACE_TAG_LAST)
84 
85 #ifndef ATRACE_TAG
86 #define ATRACE_TAG ATRACE_TAG_NEVER
87 #elif ATRACE_TAG > ATRACE_TAG_VALID_MASK
88 #error ATRACE_TAG must be defined to be one of the tags defined in cutils/trace.h
89 #endif
90 
91 /**
92  * Opens the trace file for writing and reads the property for initial tags.
93  * The atrace.tags.enableflags property sets the tags to trace.
94  * This function should not be explicitly called, the first call to any normal
95  * trace function will cause it to be run safely.
96  */
97 void atrace_setup();
98 
99 /**
100  * If tracing is ready, set atrace_enabled_tags to the system property
101  * debug.atrace.tags.enableflags. Can be used as a sysprop change callback.
102  */
103 void atrace_update_tags();
104 
105 /**
106  * Set whether tracing is enabled for the current process.  This is used to
107  * prevent tracing within the Zygote process.
108  */
109 void atrace_set_tracing_enabled(bool enabled);
110 
111 /**
112  * This is always set to false. This forces code that uses an old version
113  * of this header to always call into atrace_setup, in which we call
114  * atrace_init unconditionally.
115  */
116 extern atomic_bool atrace_is_ready;
117 
118 /**
119  * Set of ATRACE_TAG flags to trace for, initialized to ATRACE_TAG_NOT_READY.
120  * A value of zero indicates setup has failed.
121  * Any other nonzero value indicates setup has succeeded, and tracing is on.
122  */
123 extern uint64_t atrace_enabled_tags;
124 
125 /**
126  * Handle to the kernel's trace buffer, initialized to -1.
127  * Any other value indicates setup has succeeded, and is a valid fd for tracing.
128  */
129 extern int atrace_marker_fd;
130 
131 /**
132  * atrace_init readies the process for tracing by opening the trace_marker file.
133  * Calling any trace function causes this to be run, so calling it is optional.
134  * This can be explicitly run to avoid setup delay on first trace function.
135  */
136 #define ATRACE_INIT() atrace_init()
137 #define ATRACE_GET_ENABLED_TAGS() atrace_get_enabled_tags()
138 
139 void atrace_init();
140 uint64_t atrace_get_enabled_tags();
141 
142 /**
143  * Test if a given tag is currently enabled.
144  * Returns nonzero if the tag is enabled, otherwise zero.
145  * It can be used as a guard condition around more expensive trace calculations.
146  */
147 #define ATRACE_ENABLED() atrace_is_tag_enabled(ATRACE_TAG)
atrace_is_tag_enabled(uint64_t tag)148 static inline uint64_t atrace_is_tag_enabled(uint64_t tag)
149 {
150     return atrace_get_enabled_tags() & tag;
151 }
152 
153 /**
154  * Trace the beginning of a context.  name is used to identify the context.
155  * This is often used to time function execution.
156  */
157 #define ATRACE_BEGIN(name) atrace_begin(ATRACE_TAG, name)
atrace_begin(uint64_t tag,const char * name)158 static inline void atrace_begin(uint64_t tag, const char* name)
159 {
160     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
161         void atrace_begin_body(const char*);
162         atrace_begin_body(name);
163     }
164 }
165 
166 /**
167  * Trace the end of a context.
168  * This should match up (and occur after) a corresponding ATRACE_BEGIN.
169  */
170 #define ATRACE_END() atrace_end(ATRACE_TAG)
atrace_end(uint64_t tag)171 static inline void atrace_end(uint64_t tag)
172 {
173     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
174         void atrace_end_body();
175         atrace_end_body();
176     }
177 }
178 
179 /**
180  * Trace the beginning of an asynchronous event. Unlike ATRACE_BEGIN/ATRACE_END
181  * contexts, asynchronous events do not need to be nested. The name describes
182  * the event, and the cookie provides a unique identifier for distinguishing
183  * simultaneous events. The name and cookie used to begin an event must be
184  * used to end it.
185  */
186 #define ATRACE_ASYNC_BEGIN(name, cookie) \
187     atrace_async_begin(ATRACE_TAG, name, cookie)
atrace_async_begin(uint64_t tag,const char * name,int32_t cookie)188 static inline void atrace_async_begin(uint64_t tag, const char* name,
189         int32_t cookie)
190 {
191     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
192         void atrace_async_begin_body(const char*, int32_t);
193         atrace_async_begin_body(name, cookie);
194     }
195 }
196 
197 /**
198  * Trace the end of an asynchronous event.
199  * This should have a corresponding ATRACE_ASYNC_BEGIN.
200  */
201 #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)202 static inline void atrace_async_end(uint64_t tag, const char* name, int32_t cookie)
203 {
204     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
205         void atrace_async_end_body(const char*, int32_t);
206         atrace_async_end_body(name, cookie);
207     }
208 }
209 
210 /**
211  * Traces an integer counter value.  name is used to identify the counter.
212  * This can be used to track how a value changes over time.
213  */
214 #define ATRACE_INT(name, value) atrace_int(ATRACE_TAG, name, value)
atrace_int(uint64_t tag,const char * name,int32_t value)215 static inline void atrace_int(uint64_t tag, const char* name, int32_t value)
216 {
217     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
218         void atrace_int_body(const char*, int32_t);
219         atrace_int_body(name, value);
220     }
221 }
222 
223 /**
224  * Traces a 64-bit integer counter value.  name is used to identify the
225  * counter. This can be used to track how a value changes over time.
226  */
227 #define ATRACE_INT64(name, value) atrace_int64(ATRACE_TAG, name, value)
atrace_int64(uint64_t tag,const char * name,int64_t value)228 static inline void atrace_int64(uint64_t tag, const char* name, int64_t value)
229 {
230     if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) {
231         void atrace_int64_body(const char*, int64_t);
232         atrace_int64_body(name, value);
233     }
234 }
235 
236 __END_DECLS
237 
238 #endif // _LIBS_CUTILS_TRACE_H
239