| // Copyright 2015 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| #ifndef SkTraceEventCommon_DEFINED |
| #define SkTraceEventCommon_DEFINED |
| |
| // This header file defines the set of trace_event macros without specifying |
| // how the events actually get collected and stored. If you need to expose trace |
| // events to some other universe, you can copy-and-paste this file as well as |
| // trace_event.h, modifying the macros contained there as necessary for the |
| // target platform. The end result is that multiple libraries can funnel events |
| // through to a shared trace event collector. |
| |
| // IMPORTANT: To avoid conflicts, if you need to modify this file for a library, |
| // land your change in base/ first, and then copy-and-paste it. |
| |
| // Trace events are for tracking application performance and resource usage. |
| // Macros are provided to track: |
| // Begin and end of function calls |
| // Counters |
| // |
| // Events are issued against categories. Whereas LOG's |
| // categories are statically defined, TRACE categories are created |
| // implicitly with a string. For example: |
| // TRACE_EVENT_INSTANT0("MY_SUBSYSTEM", "SomeImportantEvent", |
| // TRACE_EVENT_SCOPE_THREAD) |
| // |
| // It is often the case that one trace may belong in multiple categories at the |
| // same time. The first argument to the trace can be a comma-separated list of |
| // categories, forming a category group, like: |
| // |
| // TRACE_EVENT_INSTANT0("input,views", "OnMouseOver", TRACE_EVENT_SCOPE_THREAD) |
| // |
| // We can enable/disable tracing of OnMouseOver by enabling/disabling either |
| // category. |
| // |
| // Events can be INSTANT, or can be pairs of BEGIN and END in the same scope: |
| // TRACE_EVENT_BEGIN0("MY_SUBSYSTEM", "SomethingCostly") |
| // doSomethingCostly() |
| // TRACE_EVENT_END0("MY_SUBSYSTEM", "SomethingCostly") |
| // Note: our tools can't always determine the correct BEGIN/END pairs unless |
| // these are used in the same scope. Use ASYNC_BEGIN/ASYNC_END macros if you |
| // need them to be in separate scopes. |
| // |
| // A common use case is to trace entire function scopes. This |
| // issues a trace BEGIN and END automatically: |
| // void doSomethingCostly() { |
| // TRACE_EVENT0("MY_SUBSYSTEM", "doSomethingCostly"); |
| // ... |
| // } |
| // |
| // Additional parameters can be associated with an event: |
| // void doSomethingCostly2(int howMuch) { |
| // TRACE_EVENT1("MY_SUBSYSTEM", "doSomethingCostly", |
| // "howMuch", howMuch); |
| // ... |
| // } |
| // |
| // The trace system will automatically add to this information the |
| // current process id, thread id, and a timestamp in microseconds. |
| // |
| // To trace an asynchronous procedure such as an IPC send/receive, use |
| // ASYNC_BEGIN and ASYNC_END: |
| // [single threaded sender code] |
| // static int send_count = 0; |
| // ++send_count; |
| // TRACE_EVENT_ASYNC_BEGIN0("ipc", "message", send_count); |
| // Send(new MyMessage(send_count)); |
| // [receive code] |
| // void OnMyMessage(send_count) { |
| // TRACE_EVENT_ASYNC_END0("ipc", "message", send_count); |
| // } |
| // The third parameter is a unique ID to match ASYNC_BEGIN/ASYNC_END pairs. |
| // ASYNC_BEGIN and ASYNC_END can occur on any thread of any traced process. |
| // Pointers can be used for the ID parameter, and they will be mangled |
| // internally so that the same pointer on two different processes will not |
| // match. For example: |
| // class MyTracedClass { |
| // public: |
| // MyTracedClass() { |
| // TRACE_EVENT_ASYNC_BEGIN0("category", "MyTracedClass", this); |
| // } |
| // ~MyTracedClass() { |
| // TRACE_EVENT_ASYNC_END0("category", "MyTracedClass", this); |
| // } |
| // } |
| // |
| // Trace event also supports counters, which is a way to track a quantity |
| // as it varies over time. Counters are created with the following macro: |
| // TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter", g_myCounterValue); |
| // |
| // Counters are process-specific. The macro itself can be issued from any |
| // thread, however. |
| // |
| // Sometimes, you want to track two counters at once. You can do this with two |
| // counter macros: |
| // TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter0", g_myCounterValue[0]); |
| // TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter1", g_myCounterValue[1]); |
| // Or you can do it with a combined macro: |
| // TRACE_COUNTER2("MY_SUBSYSTEM", "myCounter", |
| // "bytesPinned", g_myCounterValue[0], |
| // "bytesAllocated", g_myCounterValue[1]); |
| // This indicates to the tracing UI that these counters should be displayed |
| // in a single graph, as a summed area chart. |
| // |
| // Since counters are in a global namespace, you may want to disambiguate with a |
| // unique ID, by using the TRACE_COUNTER_ID* variations. |
| // |
| // By default, trace collection is compiled in, but turned off at runtime. |
| // Collecting trace data is the responsibility of the embedding |
| // application. In Chrome's case, navigating to about:tracing will turn on |
| // tracing and display data collected across all active processes. |
| // |
| // |
| // Memory scoping note: |
| // Tracing copies the pointers, not the string content, of the strings passed |
| // in for category_group, name, and arg_names. Thus, the following code will |
| // cause problems: |
| // char* str = strdup("importantName"); |
| // TRACE_EVENT_INSTANT0("SUBSYSTEM", str); // BAD! |
| // free(str); // Trace system now has dangling pointer |
| // |
| // To avoid this issue with the |name| and |arg_name| parameters, use the |
| // TRACE_EVENT_COPY_XXX overloads of the macros at additional runtime overhead. |
| // Notes: The category must always be in a long-lived char* (i.e. static const). |
| // The |arg_values|, when used, are always deep copied with the _COPY |
| // macros. |
| // |
| // When are string argument values copied: |
| // const char* arg_values are only referenced by default: |
| // TRACE_EVENT1("category", "name", |
| // "arg1", "literal string is only referenced"); |
| // Use TRACE_STR_COPY to force copying of a const char*: |
| // TRACE_EVENT1("category", "name", |
| // "arg1", TRACE_STR_COPY("string will be copied")); |
| // std::string arg_values are always copied: |
| // TRACE_EVENT1("category", "name", |
| // "arg1", std::string("string will be copied")); |
| // |
| // |
| // Convertable notes: |
| // Converting a large data type to a string can be costly. To help with this, |
| // the trace framework provides an interface ConvertableToTraceFormat. If you |
| // inherit from it and implement the AppendAsTraceFormat method the trace |
| // framework will call back to your object to convert a trace output time. This |
| // means, if the category for the event is disabled, the conversion will not |
| // happen. |
| // |
| // class MyData : public base::trace_event::ConvertableToTraceFormat { |
| // public: |
| // MyData() {} |
| // void AppendAsTraceFormat(std::string* out) const override { |
| // out->append("{\"foo\":1}"); |
| // } |
| // private: |
| // ~MyData() override {} |
| // DISALLOW_COPY_AND_ASSIGN(MyData); |
| // }; |
| // |
| // TRACE_EVENT1("foo", "bar", "data", |
| // scoped_refptr<ConvertableToTraceFormat>(new MyData())); |
| // |
| // The trace framework will take ownership if the passed pointer and it will |
| // be free'd when the trace buffer is flushed. |
| // |
| // Note, we only do the conversion when the buffer is flushed, so the provided |
| // data object should not be modified after it's passed to the trace framework. |
| // |
| // |
| // Thread Safety: |
| // A thread safe singleton and mutex are used for thread safety. Category |
| // enabled flags are used to limit the performance impact when the system |
| // is not enabled. |
| // |
| // TRACE_EVENT macros first cache a pointer to a category. The categories are |
| // statically allocated and safe at all times, even after exit. Fetching a |
| // category is protected by the TraceLog::lock_. Multiple threads initializing |
| // the static variable is safe, as they will be serialized by the lock and |
| // multiple calls will return the same pointer to the category. |
| // |
| // Then the category_group_enabled flag is checked. This is a unsigned char, and |
| // not intended to be multithread safe. It optimizes access to AddTraceEvent |
| // which is threadsafe internally via TraceLog::lock_. The enabled flag may |
| // cause some threads to incorrectly call or skip calling AddTraceEvent near |
| // the time of the system being enabled or disabled. This is acceptable as |
| // we tolerate some data loss while the system is being enabled/disabled and |
| // because AddTraceEvent is threadsafe internally and checks the enabled state |
| // again under lock. |
| // |
| // Without the use of these static category pointers and enabled flags all |
| // trace points would carry a significant performance cost of acquiring a lock |
| // and resolving the category. |
| |
| #if defined(TRACE_EVENT0) |
| #error "Another copy of this file has already been included." |
| #endif |
| |
| // This will mark the trace event as disabled by default. The user will need |
| // to explicitly enable the event. |
| #define TRACE_DISABLED_BY_DEFAULT(name) "disabled-by-default-" name |
| |
| // Records a pair of begin and end events called "name" for the current |
| // scope, with 0, 1 or 2 associated arguments. If the category is not |
| // enabled, then this does nothing. |
| // - category and name strings must have application lifetime (statics or |
| // literals). They may not include " chars. |
| #define TRACE_EVENT0(category_group, name) \ |
| INTERNAL_TRACE_MEMORY(category_group, name) \ |
| INTERNAL_TRACE_EVENT_ADD_SCOPED(category_group, name) |
| |
| #define TRACE_EVENT1(category_group, name, arg1_name, arg1_val) \ |
| INTERNAL_TRACE_MEMORY(category_group, name) \ |
| INTERNAL_TRACE_EVENT_ADD_SCOPED(category_group, name, arg1_name, arg1_val) |
| |
| #define TRACE_EVENT2(category_group, name, arg1_name, arg1_val, arg2_name, \ |
| arg2_val) \ |
| INTERNAL_TRACE_MEMORY(category_group, name) \ |
| INTERNAL_TRACE_EVENT_ADD_SCOPED(category_group, name, arg1_name, arg1_val, \ |
| arg2_name, arg2_val) |
| |
| // Records a single event called "name" immediately, with 0, 1 or 2 |
| // associated arguments. If the category is not enabled, then this |
| // does nothing. |
| // - category and name strings must have application lifetime (statics or |
| // literals). They may not include " chars. |
| #define TRACE_EVENT_INSTANT0(category_group, name, scope) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \ |
| TRACE_EVENT_FLAG_NONE | scope) |
| #define TRACE_EVENT_INSTANT1(category_group, name, scope, arg1_name, arg1_val) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \ |
| TRACE_EVENT_FLAG_NONE | scope, arg1_name, arg1_val) |
| #define TRACE_EVENT_INSTANT2(category_group, name, scope, arg1_name, arg1_val, \ |
| arg2_name, arg2_val) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \ |
| TRACE_EVENT_FLAG_NONE | scope, arg1_name, arg1_val, \ |
| arg2_name, arg2_val) |
| #define TRACE_EVENT_COPY_INSTANT0(category_group, name, scope) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \ |
| TRACE_EVENT_FLAG_COPY | scope) |
| #define TRACE_EVENT_COPY_INSTANT1(category_group, name, scope, arg1_name, \ |
| arg1_val) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \ |
| TRACE_EVENT_FLAG_COPY | scope, arg1_name, arg1_val) |
| #define TRACE_EVENT_COPY_INSTANT2(category_group, name, scope, arg1_name, \ |
| arg1_val, arg2_name, arg2_val) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, category_group, name, \ |
| TRACE_EVENT_FLAG_COPY | scope, arg1_name, arg1_val, \ |
| arg2_name, arg2_val) |
| |
| // Records the value of a counter called "name" immediately. Value |
| // must be representable as a 32 bit integer. |
| // - category and name strings must have application lifetime (statics or |
| // literals). They may not include " chars. |
| #define TRACE_COUNTER1(category_group, name, value) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \ |
| TRACE_EVENT_FLAG_NONE, "value", \ |
| static_cast<int>(value)) |
| #define TRACE_COPY_COUNTER1(category_group, name, value) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \ |
| TRACE_EVENT_FLAG_COPY, "value", \ |
| static_cast<int>(value)) |
| |
| // Records the values of a multi-parted counter called "name" immediately. |
| // The UI will treat value1 and value2 as parts of a whole, displaying their |
| // values as a stacked-bar chart. |
| // - category and name strings must have application lifetime (statics or |
| // literals). They may not include " chars. |
| #define TRACE_COUNTER2(category_group, name, value1_name, value1_val, \ |
| value2_name, value2_val) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \ |
| TRACE_EVENT_FLAG_NONE, value1_name, \ |
| static_cast<int>(value1_val), value2_name, \ |
| static_cast<int>(value2_val)) |
| #define TRACE_COPY_COUNTER2(category_group, name, value1_name, value1_val, \ |
| value2_name, value2_val) \ |
| INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, category_group, name, \ |
| TRACE_EVENT_FLAG_COPY, value1_name, \ |
| static_cast<int>(value1_val), value2_name, \ |
| static_cast<int>(value2_val)) |
| |
| // Macro to efficiently determine if a given category group is enabled. |
| #define TRACE_EVENT_CATEGORY_GROUP_ENABLED(category_group, ret) \ |
| do { \ |
| INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category_group); \ |
| if (INTERNAL_TRACE_EVENT_CATEGORY_GROUP_ENABLED_FOR_RECORDING_MODE()) { \ |
| *ret = true; \ |
| } else { \ |
| *ret = false; \ |
| } \ |
| } while (0) |
| |
| // Macro to efficiently determine, through polling, if a new trace has begun. |
| #define TRACE_EVENT_IS_NEW_TRACE(ret) \ |
| do { \ |
| static int INTERNAL_TRACE_EVENT_UID(lastRecordingNumber) = 0; \ |
| int num_traces_recorded = TRACE_EVENT_API_GET_NUM_TRACES_RECORDED(); \ |
| if (num_traces_recorded != -1 && \ |
| num_traces_recorded != \ |
| INTERNAL_TRACE_EVENT_UID(lastRecordingNumber)) { \ |
| INTERNAL_TRACE_EVENT_UID(lastRecordingNumber) = num_traces_recorded; \ |
| *ret = true; \ |
| } else { \ |
| *ret = false; \ |
| } \ |
| } while (0) |
| |
| // Notes regarding the following definitions: |
| // New values can be added and propagated to third party libraries, but existing |
| // definitions must never be changed, because third party libraries may use old |
| // definitions. |
| |
| // Phase indicates the nature of an event entry. E.g. part of a begin/end pair. |
| #define TRACE_EVENT_PHASE_BEGIN ('B') |
| #define TRACE_EVENT_PHASE_END ('E') |
| #define TRACE_EVENT_PHASE_COMPLETE ('X') |
| #define TRACE_EVENT_PHASE_INSTANT ('I') |
| #define TRACE_EVENT_PHASE_ASYNC_BEGIN ('S') |
| #define TRACE_EVENT_PHASE_ASYNC_STEP_INTO ('T') |
| #define TRACE_EVENT_PHASE_ASYNC_STEP_PAST ('p') |
| #define TRACE_EVENT_PHASE_ASYNC_END ('F') |
| #define TRACE_EVENT_PHASE_NESTABLE_ASYNC_BEGIN ('b') |
| #define TRACE_EVENT_PHASE_NESTABLE_ASYNC_END ('e') |
| #define TRACE_EVENT_PHASE_NESTABLE_ASYNC_INSTANT ('n') |
| #define TRACE_EVENT_PHASE_FLOW_BEGIN ('s') |
| #define TRACE_EVENT_PHASE_FLOW_STEP ('t') |
| #define TRACE_EVENT_PHASE_FLOW_END ('f') |
| #define TRACE_EVENT_PHASE_METADATA ('M') |
| #define TRACE_EVENT_PHASE_COUNTER ('C') |
| #define TRACE_EVENT_PHASE_SAMPLE ('P') |
| #define TRACE_EVENT_PHASE_CREATE_OBJECT ('N') |
| #define TRACE_EVENT_PHASE_SNAPSHOT_OBJECT ('O') |
| #define TRACE_EVENT_PHASE_DELETE_OBJECT ('D') |
| #define TRACE_EVENT_PHASE_MEMORY_DUMP ('v') |
| #define TRACE_EVENT_PHASE_MARK ('R') |
| |
| // Flags for changing the behavior of TRACE_EVENT_API_ADD_TRACE_EVENT. |
| #define TRACE_EVENT_FLAG_NONE (static_cast<unsigned int>(0)) |
| #define TRACE_EVENT_FLAG_COPY (static_cast<unsigned int>(1 << 0)) |
| #define TRACE_EVENT_FLAG_HAS_ID (static_cast<unsigned int>(1 << 1)) |
| #define TRACE_EVENT_FLAG_MANGLE_ID (static_cast<unsigned int>(1 << 2)) |
| #define TRACE_EVENT_FLAG_SCOPE_OFFSET (static_cast<unsigned int>(1 << 3)) |
| #define TRACE_EVENT_FLAG_SCOPE_EXTRA (static_cast<unsigned int>(1 << 4)) |
| #define TRACE_EVENT_FLAG_EXPLICIT_TIMESTAMP (static_cast<unsigned int>(1 << 5)) |
| #define TRACE_EVENT_FLAG_ASYNC_TTS (static_cast<unsigned int>(1 << 6)) |
| #define TRACE_EVENT_FLAG_BIND_TO_ENCLOSING (static_cast<unsigned int>(1 << 7)) |
| #define TRACE_EVENT_FLAG_FLOW_IN (static_cast<unsigned int>(1 << 8)) |
| #define TRACE_EVENT_FLAG_FLOW_OUT (static_cast<unsigned int>(1 << 9)) |
| #define TRACE_EVENT_FLAG_HAS_CONTEXT_ID (static_cast<unsigned int>(1 << 10)) |
| |
| #define TRACE_EVENT_FLAG_SCOPE_MASK \ |
| (static_cast<unsigned int>(TRACE_EVENT_FLAG_SCOPE_OFFSET | \ |
| TRACE_EVENT_FLAG_SCOPE_EXTRA)) |
| |
| // Type values for identifying types in the TraceValue union. |
| #define TRACE_VALUE_TYPE_BOOL (static_cast<unsigned char>(1)) |
| #define TRACE_VALUE_TYPE_UINT (static_cast<unsigned char>(2)) |
| #define TRACE_VALUE_TYPE_INT (static_cast<unsigned char>(3)) |
| #define TRACE_VALUE_TYPE_DOUBLE (static_cast<unsigned char>(4)) |
| #define TRACE_VALUE_TYPE_POINTER (static_cast<unsigned char>(5)) |
| #define TRACE_VALUE_TYPE_STRING (static_cast<unsigned char>(6)) |
| #define TRACE_VALUE_TYPE_COPY_STRING (static_cast<unsigned char>(7)) |
| #define TRACE_VALUE_TYPE_CONVERTABLE (static_cast<unsigned char>(8)) |
| |
| // Enum reflecting the scope of an INSTANT event. Must fit within |
| // TRACE_EVENT_FLAG_SCOPE_MASK. |
| #define TRACE_EVENT_SCOPE_GLOBAL (static_cast<unsigned char>(0 << 3)) |
| #define TRACE_EVENT_SCOPE_PROCESS (static_cast<unsigned char>(1 << 3)) |
| #define TRACE_EVENT_SCOPE_THREAD (static_cast<unsigned char>(2 << 3)) |
| |
| #define TRACE_EVENT_SCOPE_NAME_GLOBAL ('g') |
| #define TRACE_EVENT_SCOPE_NAME_PROCESS ('p') |
| #define TRACE_EVENT_SCOPE_NAME_THREAD ('t') |
| #endif // SkTraceEventCommon_DEFINED |
