Chromium Embedded Framework (CEF)  117.1.0+ga287baf+chromium-117.0.5938.62
cef_trace_event.h File Reference

Trace events are for tracking application performance and resource usage. More...

#include "include/internal/cef_trace_event_internal.h"

Macros

#define TRACE_EVENT0(category, name)
 Records a pair of begin and end events called "name" for the current scope, with 0, 1 or 2 associated arguments. More...
 
#define TRACE_EVENT1(category, name, arg1_name, arg1_val)
 
#define TRACE_EVENT2(category, name, arg1_name, arg1_val, arg2_name, arg2_val)
 
#define CEF_INTERNAL_TRACE_EVENT_UID3(a, b)   cef_trace_event_unique_##a##b
 
#define CEF_INTERNAL_TRACE_EVENT_UID2(a, b)   CEF_INTERNAL_TRACE_EVENT_UID3(a, b)
 
#define CEF_INTERNAL_TRACE_EVENT_UID(name_prefix)    CEF_INTERNAL_TRACE_EVENT_UID2(name_prefix, __LINE__)
 
#define CEF_INTERNAL_TRACE_END_ON_SCOPE_CLOSE(category, name)
 
#define TRACE_EVENT_INSTANT0(category, name)    cef_trace_event_instant(category, name, NULL, 0, NULL, 0)
 Records a single event called "name" immediately, with 0, 1 or 2 associated arguments. More...
 
#define TRACE_EVENT_INSTANT1(category, name, arg1_name, arg1_val)    cef_trace_event_instant(category, name, arg1_name, arg1_val, NULL, 0)
 
#define TRACE_EVENT_INSTANT2(category, name, arg1_name, arg1_val, arg2_name, arg2_val)
 
#define TRACE_EVENT_BEGIN0(category, name)    cef_trace_event_begin(category, name, NULL, 0, NULL, 0)
 Records a single BEGIN event called "name" immediately, with 0, 1 or 2 associated arguments. More...
 
#define TRACE_EVENT_BEGIN1(category, name, arg1_name, arg1_val)    cef_trace_event_begin(category, name, arg1_name, arg1_val, NULL, 0)
 
#define TRACE_EVENT_BEGIN2(category, name, arg1_name, arg1_val, arg2_name, arg2_val)
 
#define TRACE_EVENT_END0(category, name)    cef_trace_event_end(category, name, NULL, 0, NULL, 0)
 Records a single END event for "name" immediately. More...
 
#define TRACE_EVENT_END1(category, name, arg1_name, arg1_val)    cef_trace_event_end(category, name, arg1_name, arg1_val, NULL, 0)
 
#define TRACE_EVENT_END2(category, name, arg1_name, arg1_val, arg2_name, arg2_val)    cef_trace_event_end(category, name, arg1_name, arg1_val, arg2_name, arg2_val)
 
#define TRACE_COUNTER1(category, name, value)    cef_trace_counter(category, name, NULL, value, NULL, 0)
 Records the value of a counter called "name" immediately. More...
 
#define TRACE_COUNTER2(category, name, value1_name, value1_val, value2_name, value2_val)
 Records the values of a multi-parted counter called "name" immediately. More...
 
#define TRACE_COUNTER_ID1(category, name, id, value)    cef_trace_counter_id(category, name, id, NULL, value, NULL, 0)
 Records the value of a counter called "name" immediately. More...
 
#define TRACE_COUNTER_ID2(category, name, id, value1_name, value1_val, value2_name, value2_val)
 Records the values of a multi-parted counter called "name" immediately. More...
 
#define TRACE_EVENT_ASYNC_BEGIN0(category, name, id)    cef_trace_event_async_begin(category, name, id, NULL, 0, NULL, 0)
 Records a single ASYNC_BEGIN event called "name" immediately, with 0, 1 or 2 associated arguments. More...
 
#define TRACE_EVENT_ASYNC_BEGIN1(category, name, id, arg1_name, arg1_val)    cef_trace_event_async_begin(category, name, id, arg1_name, arg1_val, NULL, 0)
 
#define TRACE_EVENT_ASYNC_BEGIN2(category, name, id, arg1_name, arg1_val, arg2_name, arg2_val)
 
#define TRACE_EVENT_ASYNC_STEP_INTO0(category, name, id, step)    cef_trace_event_async_step_into(category, name, id, step, NULL, 0)
 Records a single ASYNC_STEP_INTO event for |step| immediately. More...
 
#define TRACE_EVENT_ASYNC_STEP_INTO1(category, name, id, step, arg1_name, arg1_val)    cef_trace_event_async_step_into(category, name, id, step, arg1_name, arg1_val)
 
#define TRACE_EVENT_ASYNC_STEP_PAST0(category, name, id, step)    cef_trace_event_async_step_past(category, name, id, step, NULL, 0)
 Records a single ASYNC_STEP_PAST event for |step| immediately. More...
 
#define TRACE_EVENT_ASYNC_STEP_PAST1(category, name, id, step, arg1_name, arg1_val)    cef_trace_event_async_step_past(category, name, id, step, arg1_name, arg1_val)
 
#define TRACE_EVENT_ASYNC_END0(category, name, id)    cef_trace_event_async_end(category, name, id, NULL, 0, NULL, 0)
 Records a single ASYNC_END event for "name" immediately. More...
 
#define TRACE_EVENT_ASYNC_END1(category, name, id, arg1_name, arg1_val)    cef_trace_event_async_end(category, name, id, arg1_name, arg1_val, NULL, 0)
 
#define TRACE_EVENT_ASYNC_END2(category, name, id, arg1_name, arg1_val, arg2_name, arg2_val)
 

Detailed Description

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")

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);
    }
  }

The 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 disembiguate 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 CEF's case, calling BeginTracing will turn on tracing on all active processes.

Memory scoping note: Tracing copies the pointers, not the string content, of the strings passed in for category, name, and arg_names. Thus, the following code will cause problems:

    char* str = strdup("impprtantName");
    TRACE_EVENT_INSTANT0("SUBSYSTEM", str);  // BAD!
    free(str);                   // Trace system now has dangling pointer

Thread Safety: All macros are thread safe and can be used from any process.

Macro Definition Documentation

◆ CEF_INTERNAL_TRACE_END_ON_SCOPE_CLOSE

#define CEF_INTERNAL_TRACE_END_ON_SCOPE_CLOSE (   category,
  name 
)
Value:
cef_trace_event::CefTraceEndOnScopeClose CEF_INTERNAL_TRACE_EVENT_UID( \
profileScope)(category, name)
#define CEF_INTERNAL_TRACE_EVENT_UID(name_prefix)
Definition: cef_trace_event.h:190

◆ CEF_INTERNAL_TRACE_EVENT_UID

#define CEF_INTERNAL_TRACE_EVENT_UID (   name_prefix)     CEF_INTERNAL_TRACE_EVENT_UID2(name_prefix, __LINE__)

◆ CEF_INTERNAL_TRACE_EVENT_UID2

#define CEF_INTERNAL_TRACE_EVENT_UID2 (   a,
 
)    CEF_INTERNAL_TRACE_EVENT_UID3(a, b)

◆ CEF_INTERNAL_TRACE_EVENT_UID3

#define CEF_INTERNAL_TRACE_EVENT_UID3 (   a,
 
)    cef_trace_event_unique_##a##b

◆ TRACE_COUNTER1

#define TRACE_COUNTER1 (   category,
  name,
  value 
)     cef_trace_counter(category, name, NULL, value, NULL, 0)

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.

◆ TRACE_COUNTER2

#define TRACE_COUNTER2 (   category,
  name,
  value1_name,
  value1_val,
  value2_name,
  value2_val 
)
Value:
cef_trace_counter(category, name, value1_name, value1_val, value2_name, \
value2_val)

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.

◆ TRACE_COUNTER_ID1

#define TRACE_COUNTER_ID1 (   category,
  name,
  id,
  value 
)     cef_trace_counter_id(category, name, id, NULL, value, NULL, 0)

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.
  • |id| is used to disambiguate counters with the same name. It must either be a pointer or an integer value up to 64 bits. If it's a pointer, the bits will be xored with a hash of the process ID so that the same pointer on two different processes will not collide.

◆ TRACE_COUNTER_ID2

#define TRACE_COUNTER_ID2 (   category,
  name,
  id,
  value1_name,
  value1_val,
  value2_name,
  value2_val 
)
Value:
cef_trace_counter_id(category, name, id, value1_name, value1_val, \
value2_name, value2_val)

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.
  • |id| is used to disambiguate counters with the same name. It must either be a pointer or an integer value up to 64 bits. If it's a pointer, the bits will be xored with a hash of the process ID so that the same pointer on two different processes will not collide.

◆ TRACE_EVENT0

#define TRACE_EVENT0 (   category,
  name 
)
Value:
cef_trace_event_begin(category, name, NULL, 0, NULL, 0); \
CEF_INTERNAL_TRACE_END_ON_SCOPE_CLOSE(category, 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.

◆ TRACE_EVENT1

#define TRACE_EVENT1 (   category,
  name,
  arg1_name,
  arg1_val 
)
Value:
cef_trace_event_begin(category, name, arg1_name, arg1_val, NULL, 0); \
CEF_INTERNAL_TRACE_END_ON_SCOPE_CLOSE(category, name)

◆ TRACE_EVENT2

#define TRACE_EVENT2 (   category,
  name,
  arg1_name,
  arg1_val,
  arg2_name,
  arg2_val 
)
Value:
cef_trace_event_begin(category, name, arg1_name, arg1_val, arg2_name, \
arg2_val); \
CEF_INTERNAL_TRACE_END_ON_SCOPE_CLOSE(category, name)

◆ TRACE_EVENT_ASYNC_BEGIN0

#define TRACE_EVENT_ASYNC_BEGIN0 (   category,
  name,
  id 
)     cef_trace_event_async_begin(category, name, id, NULL, 0, NULL, 0)

Records a single ASYNC_BEGIN 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.
  • |id| is used to match the ASYNC_BEGIN event with the ASYNC_END event. ASYNC events are considered to match if their category, name and id values all match. |id| must either be a pointer or an integer value up to 64 bits. If it's a pointer, the bits will be xored with a hash of the process ID sothat the same pointer on two different processes will not collide. An asynchronous operation can consist of multiple phases. The first phase is defined by the ASYNC_BEGIN calls. Additional phases can be defined using the ASYNC_STEP_BEGIN macros. When the operation completes, call ASYNC_END. An async operation can span threads and processes, but all events in that operation must use the same |name| and |id|. Each event can have its own args.

◆ TRACE_EVENT_ASYNC_BEGIN1

#define TRACE_EVENT_ASYNC_BEGIN1 (   category,
  name,
  id,
  arg1_name,
  arg1_val 
)     cef_trace_event_async_begin(category, name, id, arg1_name, arg1_val, NULL, 0)

◆ TRACE_EVENT_ASYNC_BEGIN2

#define TRACE_EVENT_ASYNC_BEGIN2 (   category,
  name,
  id,
  arg1_name,
  arg1_val,
  arg2_name,
  arg2_val 
)
Value:
cef_trace_event_async_begin(category, name, id, arg1_name, arg1_val, \
arg2_name, arg2_val)

◆ TRACE_EVENT_ASYNC_END0

#define TRACE_EVENT_ASYNC_END0 (   category,
  name,
  id 
)     cef_trace_event_async_end(category, name, id, NULL, 0, NULL, 0)

Records a single ASYNC_END event for "name" immediately.

If the category is not enabled, then this does nothing.

◆ TRACE_EVENT_ASYNC_END1

#define TRACE_EVENT_ASYNC_END1 (   category,
  name,
  id,
  arg1_name,
  arg1_val 
)     cef_trace_event_async_end(category, name, id, arg1_name, arg1_val, NULL, 0)

◆ TRACE_EVENT_ASYNC_END2

#define TRACE_EVENT_ASYNC_END2 (   category,
  name,
  id,
  arg1_name,
  arg1_val,
  arg2_name,
  arg2_val 
)
Value:
cef_trace_event_async_end(category, name, id, arg1_name, arg1_val, \
arg2_name, arg2_val)

◆ TRACE_EVENT_ASYNC_STEP_INTO0

#define TRACE_EVENT_ASYNC_STEP_INTO0 (   category,
  name,
  id,
  step 
)     cef_trace_event_async_step_into(category, name, id, step, NULL, 0)

Records a single ASYNC_STEP_INTO event for |step| immediately.

If the category is not enabled, then this does nothing. The |name| and |id| must match the ASYNC_BEGIN event above. The |step| param identifies this step within the async event. This should be called at the beginning of the next phase of an asynchronous operation. The ASYNC_BEGIN event must not have any ASYNC_STEP_PAST events.

◆ TRACE_EVENT_ASYNC_STEP_INTO1

#define TRACE_EVENT_ASYNC_STEP_INTO1 (   category,
  name,
  id,
  step,
  arg1_name,
  arg1_val 
)     cef_trace_event_async_step_into(category, name, id, step, arg1_name, arg1_val)

◆ TRACE_EVENT_ASYNC_STEP_PAST0

#define TRACE_EVENT_ASYNC_STEP_PAST0 (   category,
  name,
  id,
  step 
)     cef_trace_event_async_step_past(category, name, id, step, NULL, 0)

Records a single ASYNC_STEP_PAST event for |step| immediately.

If the category is not enabled, then this does nothing. The |name| and |id| must match the ASYNC_BEGIN event above. The |step| param identifies this step within the async event. This should be called at the beginning of the next phase of an asynchronous operation. The ASYNC_BEGIN event must not have any ASYNC_STEP_INTO events.

◆ TRACE_EVENT_ASYNC_STEP_PAST1

#define TRACE_EVENT_ASYNC_STEP_PAST1 (   category,
  name,
  id,
  step,
  arg1_name,
  arg1_val 
)     cef_trace_event_async_step_past(category, name, id, step, arg1_name, arg1_val)

◆ TRACE_EVENT_BEGIN0

#define TRACE_EVENT_BEGIN0 (   category,
  name 
)     cef_trace_event_begin(category, name, NULL, 0, NULL, 0)

Records a single BEGIN 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.

◆ TRACE_EVENT_BEGIN1

#define TRACE_EVENT_BEGIN1 (   category,
  name,
  arg1_name,
  arg1_val 
)     cef_trace_event_begin(category, name, arg1_name, arg1_val, NULL, 0)

◆ TRACE_EVENT_BEGIN2

#define TRACE_EVENT_BEGIN2 (   category,
  name,
  arg1_name,
  arg1_val,
  arg2_name,
  arg2_val 
)
Value:
cef_trace_event_begin(category, name, arg1_name, arg1_val, arg2_name, \
arg2_val)

◆ TRACE_EVENT_END0

#define TRACE_EVENT_END0 (   category,
  name 
)     cef_trace_event_end(category, name, NULL, 0, NULL, 0)

Records a single END event for "name" immediately.

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.

◆ TRACE_EVENT_END1

#define TRACE_EVENT_END1 (   category,
  name,
  arg1_name,
  arg1_val 
)     cef_trace_event_end(category, name, arg1_name, arg1_val, NULL, 0)

◆ TRACE_EVENT_END2

#define TRACE_EVENT_END2 (   category,
  name,
  arg1_name,
  arg1_val,
  arg2_name,
  arg2_val 
)     cef_trace_event_end(category, name, arg1_name, arg1_val, arg2_name, arg2_val)

◆ TRACE_EVENT_INSTANT0

#define TRACE_EVENT_INSTANT0 (   category,
  name 
)     cef_trace_event_instant(category, name, NULL, 0, NULL, 0)

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.

◆ TRACE_EVENT_INSTANT1

#define TRACE_EVENT_INSTANT1 (   category,
  name,
  arg1_name,
  arg1_val 
)     cef_trace_event_instant(category, name, arg1_name, arg1_val, NULL, 0)

◆ TRACE_EVENT_INSTANT2

#define TRACE_EVENT_INSTANT2 (   category,
  name,
  arg1_name,
  arg1_val,
  arg2_name,
  arg2_val 
)
Value:
cef_trace_event_instant(category, name, arg1_name, arg1_val, arg2_name, \
arg2_val)