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trace_event.h (43798B)


      1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 // Trace events are for tracking application performance and resource usage.
      6 // Macros are provided to track:
      7 //    Begin and end of function calls
      8 //    Counters
      9 //
     10 // Events are issued against categories. Whereas LOG's
     11 // categories are statically defined, TRACE categories are created
     12 // implicitly with a string. For example:
     13 //   TRACE_EVENT_INSTANT0("MY_SUBSYSTEM", "SomeImportantEvent")
     14 //
     15 // Events can be INSTANT, or can be pairs of BEGIN and END in the same scope:
     16 //   TRACE_EVENT_BEGIN0("MY_SUBSYSTEM", "SomethingCostly")
     17 //   doSomethingCostly()
     18 //   TRACE_EVENT_END0("MY_SUBSYSTEM", "SomethingCostly")
     19 // Note: our tools can't always determine the correct BEGIN/END pairs unless
     20 // these are used in the same scope. Use ASYNC_BEGIN/ASYNC_END macros if you need them
     21 // to be in separate scopes.
     22 //
     23 // A common use case is to trace entire function scopes. This
     24 // issues a trace BEGIN and END automatically:
     25 //   void doSomethingCostly() {
     26 //     TRACE_EVENT0("MY_SUBSYSTEM", "doSomethingCostly");
     27 //     ...
     28 //   }
     29 //
     30 // Additional parameters can be associated with an event:
     31 //   void doSomethingCostly2(int howMuch) {
     32 //     TRACE_EVENT1("MY_SUBSYSTEM", "doSomethingCostly",
     33 //         "howMuch", howMuch);
     34 //     ...
     35 //   }
     36 //
     37 // The trace system will automatically add to this information the
     38 // current process id, thread id, and a timestamp in microseconds.
     39 //
     40 // To trace an asynchronous procedure such as an IPC send/receive, use ASYNC_BEGIN and
     41 // ASYNC_END:
     42 //   [single threaded sender code]
     43 //     static int send_count = 0;
     44 //     ++send_count;
     45 //     TRACE_EVENT_ASYNC_BEGIN0("ipc", "message", send_count);
     46 //     Send(new MyMessage(send_count));
     47 //   [receive code]
     48 //     void OnMyMessage(send_count) {
     49 //       TRACE_EVENT_ASYNC_END0("ipc", "message", send_count);
     50 //     }
     51 // The third parameter is a unique ID to match ASYNC_BEGIN/ASYNC_END pairs.
     52 // ASYNC_BEGIN and ASYNC_END can occur on any thread of any traced process. Pointers can
     53 // be used for the ID parameter, and they will be mangled internally so that
     54 // the same pointer on two different processes will not match. For example:
     55 //   class MyTracedClass {
     56 //    public:
     57 //     MyTracedClass() {
     58 //       TRACE_EVENT_ASYNC_BEGIN0("category", "MyTracedClass", this);
     59 //     }
     60 //     ~MyTracedClass() {
     61 //       TRACE_EVENT_ASYNC_END0("category", "MyTracedClass", this);
     62 //     }
     63 //   }
     64 //
     65 // Trace event also supports counters, which is a way to track a quantity
     66 // as it varies over time. Counters are created with the following macro:
     67 //   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter", g_myCounterValue);
     68 //
     69 // Counters are process-specific. The macro itself can be issued from any
     70 // thread, however.
     71 //
     72 // Sometimes, you want to track two counters at once. You can do this with two
     73 // counter macros:
     74 //   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter0", g_myCounterValue[0]);
     75 //   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter1", g_myCounterValue[1]);
     76 // Or you can do it with a combined macro:
     77 //   TRACE_COUNTER2("MY_SUBSYSTEM", "myCounter",
     78 //       "bytesPinned", g_myCounterValue[0],
     79 //       "bytesAllocated", g_myCounterValue[1]);
     80 // This indicates to the tracing UI that these counters should be displayed
     81 // in a single graph, as a summed area chart.
     82 //
     83 // Since counters are in a global namespace, you may want to disembiguate with a
     84 // unique ID, by using the TRACE_COUNTER_ID* variations.
     85 //
     86 // By default, trace collection is compiled in, but turned off at runtime.
     87 // Collecting trace data is the responsibility of the embedding
     88 // application. In Chrome's case, navigating to about:tracing will turn on
     89 // tracing and display data collected across all active processes.
     90 //
     91 //
     92 // Memory scoping note:
     93 // Tracing copies the pointers, not the string content, of the strings passed
     94 // in for category, name, and arg_names. Thus, the following code will
     95 // cause problems:
     96 //     char* str = strdup("impprtantName");
     97 //     TRACE_EVENT_INSTANT0("SUBSYSTEM", str);  // BAD!
     98 //     free(str);                   // Trace system now has dangling pointer
     99 //
    100 // To avoid this issue with the |name| and |arg_name| parameters, use the
    101 // TRACE_EVENT_COPY_XXX overloads of the macros at additional runtime overhead.
    102 // Notes: The category must always be in a long-lived char* (i.e. static const).
    103 //        The |arg_values|, when used, are always deep copied with the _COPY
    104 //        macros.
    105 //
    106 // When are string argument values copied:
    107 // const char* arg_values are only referenced by default:
    108 //     TRACE_EVENT1("category", "name",
    109 //                  "arg1", "literal string is only referenced");
    110 // Use TRACE_STR_COPY to force copying of a const char*:
    111 //     TRACE_EVENT1("category", "name",
    112 //                  "arg1", TRACE_STR_COPY("string will be copied"));
    113 // std::string arg_values are always copied:
    114 //     TRACE_EVENT1("category", "name",
    115 //                  "arg1", std::string("string will be copied"));
    116 //
    117 //
    118 // Thread Safety:
    119 // A thread safe singleton and mutex are used for thread safety. Category
    120 // enabled flags are used to limit the performance impact when the system
    121 // is not enabled.
    122 //
    123 // TRACE_EVENT macros first cache a pointer to a category. The categories are
    124 // statically allocated and safe at all times, even after exit. Fetching a
    125 // category is protected by the TraceLog::lock_. Multiple threads initializing
    126 // the static variable is safe, as they will be serialized by the lock and
    127 // multiple calls will return the same pointer to the category.
    128 //
    129 // Then the category_enabled flag is checked. This is a unsigned char, and
    130 // not intended to be multithread safe. It optimizes access to addTraceEvent
    131 // which is threadsafe internally via TraceLog::lock_. The enabled flag may
    132 // cause some threads to incorrectly call or skip calling addTraceEvent near
    133 // the time of the system being enabled or disabled. This is acceptable as
    134 // we tolerate some data loss while the system is being enabled/disabled and
    135 // because addTraceEvent is threadsafe internally and checks the enabled state
    136 // again under lock.
    137 //
    138 // Without the use of these static category pointers and enabled flags all
    139 // trace points would carry a significant performance cost of aquiring a lock
    140 // and resolving the category.
    141 
    142 #ifndef COMMON_TRACE_EVENT_H_
    143 #define COMMON_TRACE_EVENT_H_
    144 
    145 #include <string>
    146 
    147 #include "common/event_tracer.h"
    148 
    149 // By default, const char* argument values are assumed to have long-lived scope
    150 // and will not be copied. Use this macro to force a const char* to be copied.
    151 #define TRACE_STR_COPY(str) WebCore::TraceEvent::TraceStringWithCopy(str)
    152 
    153 // Records a pair of begin and end events called "name" for the current
    154 // scope, with 0, 1 or 2 associated arguments. If the category is not
    155 // enabled, then this does nothing.
    156 // - category and name strings must have application lifetime (statics or
    157 //   literals). They may not include " chars.
    158 #define TRACE_EVENT0(platform, category, name) \
    159    INTERNAL_TRACE_EVENT_ADD_SCOPED(platform, category, name)
    160 #define TRACE_EVENT1(platform, category, name, arg1_name, arg1_val) \
    161    INTERNAL_TRACE_EVENT_ADD_SCOPED(platform, category, name, arg1_name, arg1_val)
    162 #define TRACE_EVENT2(category, name, arg1_name, arg1_val, arg2_name, arg2_val)                \
    163    INTERNAL_TRACE_EVENT_ADD_SCOPED(platform, category, name, arg1_name, arg1_val, arg2_name, \
    164                                    arg2_val)
    165 
    166 // Records a single event called "name" immediately, with 0, 1 or 2
    167 // associated arguments. If the category is not enabled, then this
    168 // does nothing.
    169 // - category and name strings must have application lifetime (statics or
    170 //   literals). They may not include " chars.
    171 #define TRACE_EVENT_INSTANT0(platform, category, name)                            \
    172    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_INSTANT, category, name, \
    173                             TRACE_EVENT_FLAG_NONE)
    174 #define TRACE_EVENT_INSTANT1(platform, category, name, arg1_name, arg1_val)       \
    175    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_INSTANT, category, name, \
    176                             TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
    177 #define TRACE_EVENT_INSTANT2(platform, category, name, arg1_name, arg1_val, arg2_name, arg2_val) \
    178    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_INSTANT, category, name,                \
    179                             TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
    180 #define TRACE_EVENT_COPY_INSTANT0(platform, category, name)                       \
    181    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_INSTANT, category, name, \
    182                             TRACE_EVENT_FLAG_COPY)
    183 #define TRACE_EVENT_COPY_INSTANT1(platform, category, name, arg1_name, arg1_val)  \
    184    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_INSTANT, category, name, \
    185                             TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
    186 #define TRACE_EVENT_COPY_INSTANT2(platform, category, name, arg1_name, arg1_val, arg2_name, \
    187                                  arg2_val)                                                 \
    188    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_INSTANT, category, name,           \
    189                             TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name, arg2_val)
    190 
    191 // Records a single BEGIN event called "name" immediately, with 0, 1 or 2
    192 // associated arguments. If the category is not enabled, then this
    193 // does nothing.
    194 // - category and name strings must have application lifetime (statics or
    195 //   literals). They may not include " chars.
    196 #define TRACE_EVENT_BEGIN0(platform, category, name)                            \
    197    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_BEGIN, category, name, \
    198                             TRACE_EVENT_FLAG_NONE)
    199 #define TRACE_EVENT_BEGIN1(platform, category, name, arg1_name, arg1_val)       \
    200    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_BEGIN, category, name, \
    201                             TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
    202 #define TRACE_EVENT_BEGIN2(platform, category, name, arg1_name, arg1_val, arg2_name, arg2_val) \
    203    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_BEGIN, category, name,                \
    204                             TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
    205 #define TRACE_EVENT_COPY_BEGIN0(platform, category, name)                       \
    206    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_BEGIN, category, name, \
    207                             TRACE_EVENT_FLAG_COPY)
    208 #define TRACE_EVENT_COPY_BEGIN1(platform, category, name, arg1_name, arg1_val)  \
    209    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_BEGIN, category, name, \
    210                             TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
    211 #define TRACE_EVENT_COPY_BEGIN2(platform, category, name, arg1_name, arg1_val, arg2_name, \
    212                                arg2_val)                                                 \
    213    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_BEGIN, category, name,           \
    214                             TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name, arg2_val)
    215 
    216 // Records a single END event for "name" immediately. If the category
    217 // is not enabled, then this does nothing.
    218 // - category and name strings must have application lifetime (statics or
    219 //   literals). They may not include " chars.
    220 #define TRACE_EVENT_END0(platform, category, name) \
    221    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_END, category, name, TRACE_EVENT_FLAG_NONE)
    222 #define TRACE_EVENT_END1(platform, category, name, arg1_name, arg1_val)       \
    223    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_END, category, name, \
    224                             TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
    225 #define TRACE_EVENT_END2(platform, category, name, arg1_name, arg1_val, arg2_name, arg2_val) \
    226    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_END, category, name,                \
    227                             TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name, arg2_val)
    228 #define TRACE_EVENT_COPY_END0(platform, category, name) \
    229    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_END, category, name, TRACE_EVENT_FLAG_COPY)
    230 #define TRACE_EVENT_COPY_END1(platform, category, name, arg1_name, arg1_val)  \
    231    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_END, category, name, \
    232                             TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
    233 #define TRACE_EVENT_COPY_END2(platform, category, name, arg1_name, arg1_val, arg2_name, arg2_val) \
    234    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_END, category, name,                     \
    235                             TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name, arg2_val)
    236 
    237 // Records the value of a counter called "name" immediately. Value
    238 // must be representable as a 32 bit integer.
    239 // - category and name strings must have application lifetime (statics or
    240 //   literals). They may not include " chars.
    241 #define TRACE_COUNTER1(platform, category, name, value)                           \
    242    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_COUNTER, category, name, \
    243                             TRACE_EVENT_FLAG_NONE, "value", static_cast<int>(value))
    244 #define TRACE_COPY_COUNTER1(platform, category, name, value)                      \
    245    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_COUNTER, category, name, \
    246                             TRACE_EVENT_FLAG_COPY, "value", static_cast<int>(value))
    247 
    248 // Records the values of a multi-parted counter called "name" immediately.
    249 // The UI will treat value1 and value2 as parts of a whole, displaying their
    250 // values as a stacked-bar chart.
    251 // - category and name strings must have application lifetime (statics or
    252 //   literals). They may not include " chars.
    253 #define TRACE_COUNTER2(platform, category, name, value1_name, value1_val, value2_name, value2_val) \
    254    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_COUNTER, category, name,                  \
    255                             TRACE_EVENT_FLAG_NONE, value1_name, static_cast<int>(value1_val),     \
    256                             value2_name, static_cast<int>(value2_val))
    257 #define TRACE_COPY_COUNTER2(platform, category, name, value1_name, value1_val, value2_name,    \
    258                            value2_val)                                                        \
    259    INTERNAL_TRACE_EVENT_ADD(platform, TRACE_EVENT_PHASE_COUNTER, category, name,              \
    260                             TRACE_EVENT_FLAG_COPY, value1_name, static_cast<int>(value1_val), \
    261                             value2_name, static_cast<int>(value2_val))
    262 
    263 // Records the value of a counter called "name" immediately. Value
    264 // must be representable as a 32 bit integer.
    265 // - category and name strings must have application lifetime (statics or
    266 //   literals). They may not include " chars.
    267 // - |id| is used to disambiguate counters with the same name. It must either
    268 //   be a pointer or an integer value up to 64 bits. If it's a pointer, the bits
    269 //   will be xored with a hash of the process ID so that the same pointer on
    270 //   two different processes will not collide.
    271 #define TRACE_COUNTER_ID1(platform, category, name, id, value)                                \
    272    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_COUNTER, category, name, id, \
    273                                     TRACE_EVENT_FLAG_NONE, "value", static_cast<int>(value))
    274 #define TRACE_COPY_COUNTER_ID1(platform, category, name, id, value)                           \
    275    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_COUNTER, category, name, id, \
    276                                     TRACE_EVENT_FLAG_COPY, "value", static_cast<int>(value))
    277 
    278 // Records the values of a multi-parted counter called "name" immediately.
    279 // The UI will treat value1 and value2 as parts of a whole, displaying their
    280 // values as a stacked-bar chart.
    281 // - category and name strings must have application lifetime (statics or
    282 //   literals). They may not include " chars.
    283 // - |id| is used to disambiguate counters with the same name. It must either
    284 //   be a pointer or an integer value up to 64 bits. If it's a pointer, the bits
    285 //   will be xored with a hash of the process ID so that the same pointer on
    286 //   two different processes will not collide.
    287 #define TRACE_COUNTER_ID2(platform, category, name, id, value1_name, value1_val, value2_name, \
    288                          value2_val)                                                         \
    289    INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                                         \
    290        platform, TRACE_EVENT_PHASE_COUNTER, category, name, id, TRACE_EVENT_FLAG_NONE,       \
    291        value1_name, static_cast<int>(value1_val), value2_name, static_cast<int>(value2_val))
    292 #define TRACE_COPY_COUNTER_ID2(platform, category, name, id, value1_name, value1_val, value2_name, \
    293                               value2_val)                                                         \
    294    INTERNAL_TRACE_EVENT_ADD_WITH_ID(                                                              \
    295        platform, TRACE_EVENT_PHASE_COUNTER, category, name, id, TRACE_EVENT_FLAG_COPY,            \
    296        value1_name, static_cast<int>(value1_val), value2_name, static_cast<int>(value2_val))
    297 
    298 // Records a single ASYNC_BEGIN event called "name" immediately, with 0, 1 or 2
    299 // associated arguments. If the category is not enabled, then this
    300 // does nothing.
    301 // - category and name strings must have application lifetime (statics or
    302 //   literals). They may not include " chars.
    303 // - |id| is used to match the ASYNC_BEGIN event with the ASYNC_END event. ASYNC
    304 //   events are considered to match if their category, name and id values all
    305 //   match. |id| must either be a pointer or an integer value up to 64 bits. If
    306 //   it's a pointer, the bits will be xored with a hash of the process ID so
    307 //   that the same pointer on two different processes will not collide.
    308 // An asynchronous operation can consist of multiple phases. The first phase is
    309 // defined by the ASYNC_BEGIN calls. Additional phases can be defined using the
    310 // ASYNC_STEP_BEGIN macros. When the operation completes, call ASYNC_END.
    311 // An async operation can span threads and processes, but all events in that
    312 // operation must use the same |name| and |id|. Each event can have its own
    313 // args.
    314 #define TRACE_EVENT_ASYNC_BEGIN0(platform, category, name, id)                                    \
    315    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_BEGIN, category, name, id, \
    316                                     TRACE_EVENT_FLAG_NONE)
    317 #define TRACE_EVENT_ASYNC_BEGIN1(platform, category, name, id, arg1_name, arg1_val)               \
    318    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_BEGIN, category, name, id, \
    319                                     TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
    320 #define TRACE_EVENT_ASYNC_BEGIN2(platform, category, name, id, arg1_name, arg1_val, arg2_name,    \
    321                                 arg2_val)                                                        \
    322    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_BEGIN, category, name, id, \
    323                                     TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name,       \
    324                                     arg2_val)
    325 #define TRACE_EVENT_COPY_ASYNC_BEGIN0(platform, category, name, id)                               \
    326    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_BEGIN, category, name, id, \
    327                                     TRACE_EVENT_FLAG_COPY)
    328 #define TRACE_EVENT_COPY_ASYNC_BEGIN1(platform, category, name, id, arg1_name, arg1_val)          \
    329    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_BEGIN, category, name, id, \
    330                                     TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
    331 #define TRACE_EVENT_COPY_ASYNC_BEGIN2(platform, category, name, id, arg1_name, arg1_val,          \
    332                                      arg2_name, arg2_val)                                        \
    333    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_BEGIN, category, name, id, \
    334                                     TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name,       \
    335                                     arg2_val)
    336 
    337 // Records a single ASYNC_STEP event for |step| immediately. If the category
    338 // is not enabled, then this does nothing. The |name| and |id| must match the
    339 // ASYNC_BEGIN event above. The |step| param identifies this step within the
    340 // async event. This should be called at the beginning of the next phase of an
    341 // asynchronous operation.
    342 #define TRACE_EVENT_ASYNC_STEP0(platform, category, name, id, step)                              \
    343    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_STEP, category, name, id, \
    344                                     TRACE_EVENT_FLAG_NONE, "step", step)
    345 #define TRACE_EVENT_ASYNC_STEP1(platform, category, name, id, step, arg1_name, arg1_val)         \
    346    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_STEP, category, name, id, \
    347                                     TRACE_EVENT_FLAG_NONE, "step", step, arg1_name, arg1_val)
    348 #define TRACE_EVENT_COPY_ASYNC_STEP0(platform, category, name, id, step)                         \
    349    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_STEP, category, name, id, \
    350                                     TRACE_EVENT_FLAG_COPY, "step", step)
    351 #define TRACE_EVENT_COPY_ASYNC_STEP1(platform, category, name, id, step, arg1_name, arg1_val)    \
    352    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_STEP, category, name, id, \
    353                                     TRACE_EVENT_FLAG_COPY, "step", step, arg1_name, arg1_val)
    354 
    355 // Records a single ASYNC_END event for "name" immediately. If the category
    356 // is not enabled, then this does nothing.
    357 #define TRACE_EVENT_ASYNC_END0(platform, category, name, id)                                    \
    358    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_END, category, name, id, \
    359                                     TRACE_EVENT_FLAG_NONE)
    360 #define TRACE_EVENT_ASYNC_END1(platform, category, name, id, arg1_name, arg1_val)               \
    361    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_END, category, name, id, \
    362                                     TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
    363 #define TRACE_EVENT_ASYNC_END2(platform, category, name, id, arg1_name, arg1_val, arg2_name,    \
    364                               arg2_val)                                                        \
    365    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_END, category, name, id, \
    366                                     TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, arg2_name,     \
    367                                     arg2_val)
    368 #define TRACE_EVENT_COPY_ASYNC_END0(platform, category, name, id)                               \
    369    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_END, category, name, id, \
    370                                     TRACE_EVENT_FLAG_COPY)
    371 #define TRACE_EVENT_COPY_ASYNC_END1(platform, category, name, id, arg1_name, arg1_val)          \
    372    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_END, category, name, id, \
    373                                     TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
    374 #define TRACE_EVENT_COPY_ASYNC_END2(platform, category, name, id, arg1_name, arg1_val, arg2_name, \
    375                                    arg2_val)                                                     \
    376    INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, TRACE_EVENT_PHASE_ASYNC_END, category, name, id,   \
    377                                     TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, arg2_name,       \
    378                                     arg2_val)
    379 
    380 // Creates a scope of a sampling state with the given category and name (both must
    381 // be constant strings). These states are intended for a sampling profiler.
    382 // Implementation note: we store category and name together because we don't
    383 // want the inconsistency/expense of storing two pointers.
    384 // |thread_bucket| is [0..2] and is used to statically isolate samples in one
    385 // thread from others.
    386 //
    387 // {  // The sampling state is set within this scope.
    388 //    TRACE_EVENT_SAMPLING_STATE_SCOPE_FOR_BUCKET(0, "category", "name");
    389 //    ...;
    390 // }
    391 #define TRACE_EVENT_SCOPED_SAMPLING_STATE_FOR_BUCKET(bucket_number, category, name) \
    392    TraceEvent::SamplingStateScope<bucket_number> traceEventSamplingScope(category "\0" name);
    393 
    394 // Returns a current sampling state of the given bucket.
    395 // The format of the returned string is "category\0name".
    396 #define TRACE_EVENT_GET_SAMPLING_STATE_FOR_BUCKET(bucket_number) \
    397    TraceEvent::SamplingStateScope<bucket_number>::current()
    398 
    399 // Sets a current sampling state of the given bucket.
    400 // |category| and |name| have to be constant strings.
    401 #define TRACE_EVENT_SET_SAMPLING_STATE_FOR_BUCKET(bucket_number, category, name) \
    402    TraceEvent::SamplingStateScope<bucket_number>::set(category "\0" name)
    403 
    404 // Sets a current sampling state of the given bucket.
    405 // |categoryAndName| doesn't need to be a constant string.
    406 // The format of the string is "category\0name".
    407 #define TRACE_EVENT_SET_NONCONST_SAMPLING_STATE_FOR_BUCKET(bucket_number, categoryAndName) \
    408    TraceEvent::SamplingStateScope<bucket_number>::set(categoryAndName)
    409 
    410 // Syntactic sugars for the sampling tracing in the main thread.
    411 #define TRACE_EVENT_SCOPED_SAMPLING_STATE(category, name) \
    412    TRACE_EVENT_SCOPED_SAMPLING_STATE_FOR_BUCKET(0, category, name)
    413 #define TRACE_EVENT_GET_SAMPLING_STATE() TRACE_EVENT_GET_SAMPLING_STATE_FOR_BUCKET(0)
    414 #define TRACE_EVENT_SET_SAMPLING_STATE(category, name) \
    415    TRACE_EVENT_SET_SAMPLING_STATE_FOR_BUCKET(0, category, name)
    416 #define TRACE_EVENT_SET_NONCONST_SAMPLING_STATE(categoryAndName) \
    417    TRACE_EVENT_SET_NONCONST_SAMPLING_STATE_FOR_BUCKET(0, categoryAndName)
    418 
    419 ////////////////////////////////////////////////////////////////////////////////
    420 // Implementation specific tracing API definitions.
    421 
    422 // Get a pointer to the enabled state of the given trace category. Only
    423 // long-lived literal strings should be given as the category name. The returned
    424 // pointer can be held permanently in a local static for example. If the
    425 // unsigned char is non-zero, tracing is enabled. If tracing is enabled,
    426 // TRACE_EVENT_API_ADD_TRACE_EVENT can be called. It's OK if tracing is disabled
    427 // between the load of the tracing state and the call to
    428 // TRACE_EVENT_API_ADD_TRACE_EVENT, because this flag only provides an early out
    429 // for best performance when tracing is disabled.
    430 // const unsigned char*
    431 //     TRACE_EVENT_API_GET_CATEGORY_ENABLED(const char* category_name)
    432 #define TRACE_EVENT_API_GET_CATEGORY_ENABLED angle::GetTraceCategoryEnabledFlag
    433 
    434 // Add a trace event to the platform tracing system.
    435 // void TRACE_EVENT_API_ADD_TRACE_EVENT(
    436 //                    char phase,
    437 //                    const unsigned char* category_enabled,
    438 //                    const char* name,
    439 //                    unsigned long long id,
    440 //                    int num_args,
    441 //                    const char** arg_names,
    442 //                    const unsigned char* arg_types,
    443 //                    const unsigned long long* arg_values,
    444 //                    unsigned char flags)
    445 #define TRACE_EVENT_API_ADD_TRACE_EVENT angle::AddTraceEvent
    446 
    447 ////////////////////////////////////////////////////////////////////////////////
    448 
    449 // Implementation detail: trace event macros create temporary variables
    450 // to keep instrumentation overhead low. These macros give each temporary
    451 // variable a unique name based on the line number to prevent name collissions.
    452 #define INTERNAL_TRACE_EVENT_UID3(a, b) trace_event_unique_##a##b
    453 #define INTERNAL_TRACE_EVENT_UID2(a, b) INTERNAL_TRACE_EVENT_UID3(a, b)
    454 #define INTERNALTRACEEVENTUID(name_prefix) INTERNAL_TRACE_EVENT_UID2(name_prefix, __LINE__)
    455 
    456 // Implementation detail: internal macro to create static category.
    457 #define INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(platform, category) \
    458    static const unsigned char *INTERNALTRACEEVENTUID(catstatic) = \
    459        TRACE_EVENT_API_GET_CATEGORY_ENABLED(platform, category);
    460 
    461 // Implementation detail: internal macro to create static category and add
    462 // event if the category is enabled.
    463 #define INTERNAL_TRACE_EVENT_ADD(platform, phase, category, name, flags, ...)                      \
    464    do                                                                                             \
    465    {                                                                                              \
    466        INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(platform, category);                                \
    467        if (*INTERNALTRACEEVENTUID(catstatic))                                                     \
    468        {                                                                                          \
    469            gl::TraceEvent::addTraceEvent(platform, phase, INTERNALTRACEEVENTUID(catstatic), name, \
    470                                          gl::TraceEvent::noEventId, flags, ##__VA_ARGS__);        \
    471        }                                                                                          \
    472    } while (0)
    473 
    474 // Implementation detail: internal macro to create static category and add begin
    475 // event if the category is enabled. Also adds the end event when the scope
    476 // ends.
    477 #define INTERNAL_TRACE_EVENT_ADD_SCOPED(platform, category, name, ...)                     \
    478    INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(platform, category);                            \
    479    gl::TraceEvent::TraceEndOnScopeClose INTERNALTRACEEVENTUID(profileScope);              \
    480    do                                                                                     \
    481    {                                                                                      \
    482        if (*INTERNALTRACEEVENTUID(catstatic))                                             \
    483        {                                                                                  \
    484            gl::TraceEvent::addTraceEvent(                                                 \
    485                platform, TRACE_EVENT_PHASE_BEGIN, INTERNALTRACEEVENTUID(catstatic), name, \
    486                gl::TraceEvent::noEventId, TRACE_EVENT_FLAG_NONE, ##__VA_ARGS__);          \
    487            INTERNALTRACEEVENTUID(profileScope)                                            \
    488                .initialize(platform, INTERNALTRACEEVENTUID(catstatic), name);             \
    489        }                                                                                  \
    490    } while (0)
    491 
    492 // Implementation detail: internal macro to create static category and add
    493 // event if the category is enabled.
    494 #define INTERNAL_TRACE_EVENT_ADD_WITH_ID(platform, phase, category, name, id, flags, ...)          \
    495    do                                                                                             \
    496    {                                                                                              \
    497        INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(platform, category);                                \
    498        if (*INTERNALTRACEEVENTUID(catstatic))                                                     \
    499        {                                                                                          \
    500            unsigned char traceEventFlags = flags | TRACE_EVENT_FLAG_HAS_ID;                       \
    501            gl::TraceEvent::TraceID traceEventTraceID(id, &traceEventFlags);                       \
    502            gl::TraceEvent::addTraceEvent(platform, phase, INTERNALTRACEEVENTUID(catstatic), name, \
    503                                          traceEventTraceID.data(), traceEventFlags,               \
    504                                          ##__VA_ARGS__);                                          \
    505        }                                                                                          \
    506    } while (0)
    507 
    508 // Notes regarding the following definitions:
    509 // New values can be added and propagated to third party libraries, but existing
    510 // definitions must never be changed, because third party libraries may use old
    511 // definitions.
    512 
    513 // Phase indicates the nature of an event entry. E.g. part of a begin/end pair.
    514 #define TRACE_EVENT_PHASE_BEGIN ('B')
    515 #define TRACE_EVENT_PHASE_END ('E')
    516 #define TRACE_EVENT_PHASE_INSTANT ('I')
    517 #define TRACE_EVENT_PHASE_ASYNC_BEGIN ('S')
    518 #define TRACE_EVENT_PHASE_ASYNC_STEP ('T')
    519 #define TRACE_EVENT_PHASE_ASYNC_END ('F')
    520 #define TRACE_EVENT_PHASE_METADATA ('M')
    521 #define TRACE_EVENT_PHASE_COUNTER ('C')
    522 #define TRACE_EVENT_PHASE_SAMPLE ('P')
    523 
    524 // Flags for changing the behavior of TRACE_EVENT_API_ADD_TRACE_EVENT.
    525 #define TRACE_EVENT_FLAG_NONE (static_cast<unsigned char>(0))
    526 #define TRACE_EVENT_FLAG_COPY (static_cast<unsigned char>(1 << 0))
    527 #define TRACE_EVENT_FLAG_HAS_ID (static_cast<unsigned char>(1 << 1))
    528 #define TRACE_EVENT_FLAG_MANGLE_ID (static_cast<unsigned char>(1 << 2))
    529 
    530 // Type values for identifying types in the TraceValue union.
    531 #define TRACE_VALUE_TYPE_BOOL (static_cast<unsigned char>(1))
    532 #define TRACE_VALUE_TYPE_UINT (static_cast<unsigned char>(2))
    533 #define TRACE_VALUE_TYPE_INT (static_cast<unsigned char>(3))
    534 #define TRACE_VALUE_TYPE_DOUBLE (static_cast<unsigned char>(4))
    535 #define TRACE_VALUE_TYPE_POINTER (static_cast<unsigned char>(5))
    536 #define TRACE_VALUE_TYPE_STRING (static_cast<unsigned char>(6))
    537 #define TRACE_VALUE_TYPE_COPY_STRING (static_cast<unsigned char>(7))
    538 
    539 namespace gl
    540 {
    541 
    542 namespace TraceEvent
    543 {
    544 
    545 // Specify these values when the corresponding argument of addTraceEvent is not
    546 // used.
    547 const int zeroNumArgs              = 0;
    548 const unsigned long long noEventId = 0;
    549 
    550 // TraceID encapsulates an ID that can either be an integer or pointer. Pointers
    551 // are mangled with the Process ID so that they are unlikely to collide when the
    552 // same pointer is used on different processes.
    553 class TraceID
    554 {
    555  public:
    556    explicit TraceID(const void *id, unsigned char *flags)
    557        : m_data(static_cast<unsigned long long>(reinterpret_cast<uintptr_t>(id)))
    558    {
    559        *flags |= TRACE_EVENT_FLAG_MANGLE_ID;
    560    }
    561    explicit TraceID(unsigned long long id, unsigned char *flags) : m_data(id) { (void)flags; }
    562    explicit TraceID(unsigned long id, unsigned char *flags) : m_data(id) { (void)flags; }
    563    explicit TraceID(unsigned int id, unsigned char *flags) : m_data(id) { (void)flags; }
    564    explicit TraceID(unsigned short id, unsigned char *flags) : m_data(id) { (void)flags; }
    565    explicit TraceID(unsigned char id, unsigned char *flags) : m_data(id) { (void)flags; }
    566    explicit TraceID(long long id, unsigned char *flags)
    567        : m_data(static_cast<unsigned long long>(id))
    568    {
    569        (void)flags;
    570    }
    571    explicit TraceID(long id, unsigned char *flags) : m_data(static_cast<unsigned long long>(id))
    572    {
    573        (void)flags;
    574    }
    575    explicit TraceID(int id, unsigned char *flags) : m_data(static_cast<unsigned long long>(id))
    576    {
    577        (void)flags;
    578    }
    579    explicit TraceID(short id, unsigned char *flags) : m_data(static_cast<unsigned long long>(id))
    580    {
    581        (void)flags;
    582    }
    583    explicit TraceID(signed char id, unsigned char *flags)
    584        : m_data(static_cast<unsigned long long>(id))
    585    {
    586        (void)flags;
    587    }
    588 
    589    unsigned long long data() const { return m_data; }
    590 
    591  private:
    592    unsigned long long m_data;
    593 };
    594 
    595 // Simple union to store various types as unsigned long long.
    596 union TraceValueUnion
    597 {
    598    bool m_bool;
    599    unsigned long long m_uint;
    600    long long m_int;
    601    double m_double;
    602    const void *m_pointer;
    603    const char *m_string;
    604 };
    605 
    606 // Simple container for const char* that should be copied instead of retained.
    607 class TraceStringWithCopy
    608 {
    609  public:
    610    explicit TraceStringWithCopy(const char *str) : m_str(str) {}
    611    operator const char *() const { return m_str; }
    612 
    613  private:
    614    const char *m_str;
    615 };
    616 
    617 // Define setTraceValue for each allowed type. It stores the type and
    618 // value in the return arguments. This allows this API to avoid declaring any
    619 // structures so that it is portable to third_party libraries.
    620 #define INTERNAL_DECLARE_SET_TRACE_VALUE(actual_type, union_member, value_type_id) \
    621    static inline void setTraceValue(actual_type arg, unsigned char *type,         \
    622                                     unsigned long long *value)                    \
    623    {                                                                              \
    624        TraceValueUnion typeValue;                                                 \
    625        typeValue.union_member = arg;                                              \
    626        *type                  = value_type_id;                                    \
    627        *value                 = typeValue.m_uint;                                 \
    628    }
    629 // Simpler form for int types that can be safely casted.
    630 #define INTERNAL_DECLARE_SET_TRACE_VALUE_INT(actual_type, value_type_id)   \
    631    static inline void setTraceValue(actual_type arg, unsigned char *type, \
    632                                     unsigned long long *value)            \
    633    {                                                                      \
    634        *type  = value_type_id;                                            \
    635        *value = static_cast<unsigned long long>(arg);                     \
    636    }
    637 
    638 INTERNAL_DECLARE_SET_TRACE_VALUE_INT(unsigned long long, TRACE_VALUE_TYPE_UINT)
    639 INTERNAL_DECLARE_SET_TRACE_VALUE_INT(unsigned int, TRACE_VALUE_TYPE_UINT)
    640 INTERNAL_DECLARE_SET_TRACE_VALUE_INT(unsigned short, TRACE_VALUE_TYPE_UINT)
    641 INTERNAL_DECLARE_SET_TRACE_VALUE_INT(unsigned char, TRACE_VALUE_TYPE_UINT)
    642 INTERNAL_DECLARE_SET_TRACE_VALUE_INT(long long, TRACE_VALUE_TYPE_INT)
    643 INTERNAL_DECLARE_SET_TRACE_VALUE_INT(int, TRACE_VALUE_TYPE_INT)
    644 INTERNAL_DECLARE_SET_TRACE_VALUE_INT(short, TRACE_VALUE_TYPE_INT)
    645 INTERNAL_DECLARE_SET_TRACE_VALUE_INT(signed char, TRACE_VALUE_TYPE_INT)
    646 INTERNAL_DECLARE_SET_TRACE_VALUE(bool, m_bool, TRACE_VALUE_TYPE_BOOL)
    647 INTERNAL_DECLARE_SET_TRACE_VALUE(double, m_double, TRACE_VALUE_TYPE_DOUBLE)
    648 INTERNAL_DECLARE_SET_TRACE_VALUE(const void *, m_pointer, TRACE_VALUE_TYPE_POINTER)
    649 INTERNAL_DECLARE_SET_TRACE_VALUE(const char *, m_string, TRACE_VALUE_TYPE_STRING)
    650 INTERNAL_DECLARE_SET_TRACE_VALUE(const TraceStringWithCopy &,
    651                                 m_string,
    652                                 TRACE_VALUE_TYPE_COPY_STRING)
    653 
    654 #undef INTERNAL_DECLARE_SET_TRACE_VALUE
    655 #undef INTERNAL_DECLARE_SET_TRACE_VALUE_INT
    656 
    657 static inline void setTraceValue(const std::string &arg,
    658                                 unsigned char *type,
    659                                 unsigned long long *value)
    660 {
    661    TraceValueUnion typeValue;
    662    typeValue.m_string = arg.data();
    663    *type              = TRACE_VALUE_TYPE_COPY_STRING;
    664    *value             = typeValue.m_uint;
    665 }
    666 
    667 // These addTraceEvent template functions are defined here instead of in the
    668 // macro, because the arg values could be temporary string objects. In order to
    669 // store pointers to the internal c_str and pass through to the tracing API, the
    670 // arg values must live throughout these procedures.
    671 
    672 static inline angle::TraceEventHandle addTraceEvent(angle::PlatformMethods *platform,
    673                                                    char phase,
    674                                                    const unsigned char *categoryEnabled,
    675                                                    const char *name,
    676                                                    unsigned long long id,
    677                                                    unsigned char flags)
    678 {
    679    return TRACE_EVENT_API_ADD_TRACE_EVENT(platform, phase, categoryEnabled, name, id, zeroNumArgs,
    680                                           0, 0, 0, flags);
    681 }
    682 
    683 template <class ARG1_TYPE>
    684 static inline angle::TraceEventHandle addTraceEvent(angle::PlatformMethods *platform,
    685                                                    char phase,
    686                                                    const unsigned char *categoryEnabled,
    687                                                    const char *name,
    688                                                    unsigned long long id,
    689                                                    unsigned char flags,
    690                                                    const char *arg1Name,
    691                                                    const ARG1_TYPE &arg1Val)
    692 {
    693    const int numArgs = 1;
    694    unsigned char argTypes[1];
    695    unsigned long long argValues[1];
    696    setTraceValue(arg1Val, &argTypes[0], &argValues[0]);
    697    return TRACE_EVENT_API_ADD_TRACE_EVENT(platform, phase, categoryEnabled, name, id, numArgs,
    698                                           &arg1Name, argTypes, argValues, flags);
    699 }
    700 
    701 template <class ARG1_TYPE, class ARG2_TYPE>
    702 static inline angle::TraceEventHandle addTraceEvent(angle::PlatformMethods *platform,
    703                                                    char phase,
    704                                                    const unsigned char *categoryEnabled,
    705                                                    const char *name,
    706                                                    unsigned long long id,
    707                                                    unsigned char flags,
    708                                                    const char *arg1Name,
    709                                                    const ARG1_TYPE &arg1Val,
    710                                                    const char *arg2Name,
    711                                                    const ARG2_TYPE &arg2Val)
    712 {
    713    const int numArgs       = 2;
    714    const char *argNames[2] = {arg1Name, arg2Name};
    715    unsigned char argTypes[2];
    716    unsigned long long argValues[2];
    717    setTraceValue(arg1Val, &argTypes[0], &argValues[0]);
    718    setTraceValue(arg2Val, &argTypes[1], &argValues[1]);
    719    return TRACE_EVENT_API_ADD_TRACE_EVENT(platform, phase, categoryEnabled, name, id, numArgs,
    720                                           argNames, argTypes, argValues, flags);
    721 }
    722 
    723 // Used by TRACE_EVENTx macro. Do not use directly.
    724 class TraceEndOnScopeClose
    725 {
    726  public:
    727    // Note: members of m_data intentionally left uninitialized. See initialize.
    728    TraceEndOnScopeClose() : m_pdata(0) {}
    729    ~TraceEndOnScopeClose()
    730    {
    731        if (m_pdata)
    732            addEventIfEnabled();
    733    }
    734 
    735    void initialize(angle::PlatformMethods *platform,
    736                    const unsigned char *categoryEnabled,
    737                    const char *name)
    738    {
    739        m_data.platform        = platform;
    740        m_data.categoryEnabled = categoryEnabled;
    741        m_data.name            = name;
    742        m_pdata                = &m_data;
    743    }
    744 
    745  private:
    746    // Add the end event if the category is still enabled.
    747    void addEventIfEnabled()
    748    {
    749        // Only called when m_pdata is non-null.
    750        if (*m_pdata->categoryEnabled)
    751        {
    752            TRACE_EVENT_API_ADD_TRACE_EVENT(m_pdata->platform, TRACE_EVENT_PHASE_END,
    753                                            m_pdata->categoryEnabled, m_pdata->name, noEventId,
    754                                            zeroNumArgs, 0, 0, 0, TRACE_EVENT_FLAG_NONE);
    755        }
    756    }
    757 
    758    // This Data struct workaround is to avoid initializing all the members
    759    // in Data during construction of this object, since this object is always
    760    // constructed, even when tracing is disabled. If the members of Data were
    761    // members of this class instead, compiler warnings occur about potential
    762    // uninitialized accesses.
    763    struct Data
    764    {
    765        angle::PlatformMethods *platform;
    766        const unsigned char *categoryEnabled;
    767        const char *name;
    768    };
    769    Data *m_pdata;
    770    Data m_data;
    771 };
    772 
    773 }  // namespace TraceEvent
    774 
    775 }  // namespace gl
    776 
    777 #endif