Alex Ray | 0a34643 | 2012-11-14 17:25:28 -0800 | [diff] [blame^] | 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 <unistd.h> |
| 24 | #include <cutils/atomic.h> |
| 25 | #include <cutils/compiler.h> |
| 26 | |
| 27 | __BEGIN_DECLS |
| 28 | |
| 29 | /** |
| 30 | * The ATRACE_TAG macro can be defined before including this header to trace |
| 31 | * using one of the tags defined below. It must be defined to one of the |
| 32 | * following ATRACE_TAG_* macros. The trace tag is used to filter tracing in |
| 33 | * userland to avoid some of the runtime cost of tracing when it is not desired. |
| 34 | * |
| 35 | * Defining ATRACE_TAG to be ATRACE_TAG_ALWAYS will result in the tracing always |
| 36 | * being enabled - this should ONLY be done for debug code, as userland tracing |
| 37 | * has a performance cost even when the trace is not being recorded. Defining |
| 38 | * ATRACE_TAG to be ATRACE_TAG_NEVER or leaving ATRACE_TAG undefined will result |
| 39 | * in the tracing always being disabled. |
| 40 | * |
| 41 | * ATRACE_TAG_HAL should be bitwise ORed with the relevant tags for tracing |
| 42 | * within a hardware module. For example a camera hardware module would set: |
| 43 | * #define ATRACE_TAG (ATRACE_TAG_CAMERA | ATRACE_TAG_HAL) |
| 44 | * |
| 45 | * Keep these in sync with frameworks/base/core/java/android/os/Trace.java. |
| 46 | */ |
| 47 | #define ATRACE_TAG_NEVER 0 // This tag is never enabled. |
| 48 | #define ATRACE_TAG_ALWAYS (1<<0) // This tag is always enabled. |
| 49 | #define ATRACE_TAG_GRAPHICS (1<<1) |
| 50 | #define ATRACE_TAG_INPUT (1<<2) |
| 51 | #define ATRACE_TAG_VIEW (1<<3) |
| 52 | #define ATRACE_TAG_WEBVIEW (1<<4) |
| 53 | #define ATRACE_TAG_WINDOW_MANAGER (1<<5) |
| 54 | #define ATRACE_TAG_ACTIVITY_MANAGER (1<<6) |
| 55 | #define ATRACE_TAG_SYNC_MANAGER (1<<7) |
| 56 | #define ATRACE_TAG_AUDIO (1<<8) |
| 57 | #define ATRACE_TAG_VIDEO (1<<9) |
| 58 | #define ATRACE_TAG_CAMERA (1<<10) |
| 59 | #define ATRACE_TAG_HAL (1<<11) |
| 60 | #define ATRACE_TAG_LAST ATRACE_TAG_HAL |
| 61 | |
| 62 | // Reserved for initialization. |
| 63 | #define ATRACE_TAG_NOT_READY (1LL<<63) |
| 64 | |
| 65 | #define ATRACE_TAG_VALID_MASK ((ATRACE_TAG_LAST - 1) | ATRACE_TAG_LAST) |
| 66 | |
| 67 | #ifndef ATRACE_TAG |
| 68 | #define ATRACE_TAG ATRACE_TAG_NEVER |
| 69 | #elif ATRACE_TAG > ATRACE_TAG_VALID_MASK |
| 70 | #error ATRACE_TAG must be defined to be one of the tags defined in cutils/trace.h |
| 71 | #endif |
| 72 | |
| 73 | /** |
| 74 | * Maximum size of a message that can be logged to the trace buffer. |
| 75 | * Note this message includes a tag, the pid, and the string given as the name. |
| 76 | * Names should be kept short to get the most use of the trace buffer. |
| 77 | */ |
| 78 | #define ATRACE_MESSAGE_LENGTH 1024 |
| 79 | |
| 80 | /** |
| 81 | * Opens the trace file for writing and reads the property for initial tags. |
| 82 | * The atrace.tags.enableflags property sets the tags to trace. |
| 83 | * This function should not be explicitly called, the first call to any normal |
| 84 | * trace function will cause it to be run safely. |
| 85 | */ |
| 86 | void atrace_setup(); |
| 87 | |
| 88 | /** |
| 89 | * Flag indicating whether setup has been completed, initialized to 0. |
| 90 | * Nonzero indicates setup has completed. |
| 91 | * Note: This does NOT indicate whether or not setup was successful. |
| 92 | */ |
| 93 | extern int32_t atrace_is_ready; |
| 94 | |
| 95 | /** |
| 96 | * Set of ATRACE_TAG flags to trace for, initialized to ATRACE_TAG_NOT_READY. |
| 97 | * A value of zero indicates setup has failed. |
| 98 | * Any other nonzero value indicates setup has succeeded, and tracing is on. |
| 99 | */ |
| 100 | extern uint64_t atrace_enabled_tags; |
| 101 | |
| 102 | /** |
| 103 | * Handle to the kernel's trace buffer, initialized to -1. |
| 104 | * Any other value indicates setup has succeeded, and is a valid fd for tracing. |
| 105 | */ |
| 106 | extern int atrace_marker_fd; |
| 107 | |
| 108 | /** |
| 109 | * atrace_init readies the process for tracing by opening the trace_marker file. |
| 110 | * Calling any trace function causes this to be run, so calling it is optional. |
| 111 | * This can be explicitly run to avoid setup delay on first trace function. |
| 112 | */ |
| 113 | #define ATRACE_INIT() atrace_init() |
| 114 | static inline void atrace_init() |
| 115 | { |
| 116 | if (CC_UNLIKELY(!android_atomic_acquire_load(&atrace_is_ready))) { |
| 117 | atrace_setup(); |
| 118 | } |
| 119 | } |
| 120 | |
| 121 | /** |
| 122 | * Get the mask of all tags currently enabled. |
| 123 | * It can be used as a guard condition around more expensive trace calculations. |
| 124 | * Every trace function calls this, which ensures atrace_init is run. |
| 125 | */ |
| 126 | #define ATRACE_GET_ENABLED_TAGS() atrace_get_enabled_tags() |
| 127 | static inline uint64_t atrace_get_enabled_tags() |
| 128 | { |
| 129 | atrace_init(); |
| 130 | return atrace_enabled_tags; |
| 131 | } |
| 132 | |
| 133 | /** |
| 134 | * Test if a given tag is currently enabled. |
| 135 | * Returns nonzero if the tag is enabled, otherwise zero. |
| 136 | * It can be used as a guard condition around more expensive trace calculations. |
| 137 | */ |
| 138 | #define ATRACE_ENABLED() atrace_is_tag_enabled(ATRACE_TAG) |
| 139 | static inline uint64_t atrace_is_tag_enabled(uint64_t tag) |
| 140 | { |
| 141 | return atrace_get_enabled_tags() & tag; |
| 142 | } |
| 143 | |
| 144 | /** |
| 145 | * Trace the beginning of a context. name is used to identify the context. |
| 146 | * This is often used to time function execution. |
| 147 | */ |
| 148 | #define ATRACE_BEGIN(name) atrace_begin(ATRACE_TAG, name) |
| 149 | static inline void atrace_begin(uint64_t tag, const char* name) |
| 150 | { |
| 151 | if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) { |
| 152 | char buf[ATRACE_MESSAGE_LENGTH]; |
| 153 | size_t len; |
| 154 | |
| 155 | len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "B|%d|%s", getpid(), name); |
| 156 | write(atrace_marker_fd, buf, len); |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | /** |
| 161 | * Trace the end of a context. |
| 162 | * This should match up (and occur after) a corresponding ATRACE_BEGIN. |
| 163 | */ |
| 164 | #define ATRACE_END() atrace_end(ATRACE_TAG) |
| 165 | static inline void atrace_end(uint64_t tag) |
| 166 | { |
| 167 | if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) { |
| 168 | char c = 'E'; |
| 169 | write(atrace_marker_fd, &c, 1); |
| 170 | } |
| 171 | } |
| 172 | |
| 173 | /** |
| 174 | * Traces an integer counter value. name is used to identify the counter. |
| 175 | * This can be used to track how a value changes over time. |
| 176 | */ |
| 177 | #define ATRACE_INT(name, value) atrace_int(ATRACE_TAG, name, value) |
| 178 | static inline void atrace_int(uint64_t tag, const char* name, int32_t value) |
| 179 | { |
| 180 | if (CC_UNLIKELY(atrace_is_tag_enabled(tag))) { |
| 181 | char buf[ATRACE_MESSAGE_LENGTH]; |
| 182 | size_t len; |
| 183 | |
| 184 | len = snprintf(buf, ATRACE_MESSAGE_LENGTH, "C|%d|%s|%d", |
| 185 | getpid(), name, value); |
| 186 | write(atrace_marker_fd, buf, len); |
| 187 | } |
| 188 | } |
| 189 | |
| 190 | __END_DECLS |
| 191 | |
| 192 | #endif // _LIBS_CUTILS_TRACE_H |