Adding raw tracing to trace framework.

base/debug/trace_event.h

Index: base/debug/trace_event.h
diff --git a/base/debug/trace_event.h b/base/debug/trace_event.h
index 07863ad997b3d56fd46f8033a0775f08b56b279a..dfe4e0d674aeb7eff124656da8421f2981ba548a 100644
--- a/base/debug/trace_event.h
+++ b/base/debug/trace_event.h
@@ -265,6 +265,12 @@
         category, name, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, \
         arg2_name, arg2_val)
 
+// Similar to TRACE_EVENT_BEGINx but allowing a custom |thread_name| and
+// a custom |at| timestamp to be provided.
+#define TRACE_EVENT_COPY_BEGIN_EXPLICIT0(category, name, id, at) \

[nduca, 2012/12/04 05:09:38]

at->ts?

we're not using a custom |thread_name| anymore?

if you 

BEGIN_WITH_EXPLICIT_TIMESTAMP?


Add the non-copying forms too.

[dsinclair, 2012/12/04 15:02:38]

Done 
No, we ended up using a thread to handle the outputting for us. I couldn't
figure out any way to go from a thread id to a thread name without being on the
actual thread. Using PostTask it was actually pretty easy to get the output
working on the thread.
Done

+    INTERNAL_TRACE_EVENT_ADD_EXPLICIT(TRACE_EVENT_PHASE_ASYNC_BEGIN, \
+        category, name, at, id, TRACE_EVENT_FLAG_COPY)
+
 // 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
@@ -292,6 +298,12 @@
         category, name, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, \
         arg2_name, arg2_val)
 
+// Similar to TRACE_EVENT_ENDx but allowing a custom |thread_name| and
+// a custom |at| timestamp to be provided.
+#define TRACE_EVENT_COPY_END_EXPLICIT0(category, name, id, at) \
+    INTERNAL_TRACE_EVENT_ADD_EXPLICIT(TRACE_EVENT_PHASE_ASYNC_END, \
+        category, name, at, id, TRACE_EVENT_FLAG_COPY)
+
 // Time threshold event:
 // Only record the event if the duration is greater than the specified
 // threshold_us (time in microseconds).
@@ -597,6 +609,24 @@
 #define TRACE_EVENT_API_ADD_TRACE_EVENT \
     base::debug::TraceLog::GetInstance()->AddTraceEvent
 
+// Add a trace event to the platform tracing system. Returns thresholdBeginId
+// for use in a corresponding end TRACE_EVENT_API_ADD_TRACE_EVENT_EXPLICIT call.
+// int TRACE_EVENT_API_ADD_TRACE_EVENT_EXPLICIT(
+//                    char phase,
+//                    const unsigned char* category_enabled,
+//                    const char* name,
+//                    int64 timestamp,
+//                    unsigned long long id,
+//                    int num_args,
+//                    const char** arg_names,
+//                    const unsigned char* arg_types,
+//                    const unsigned long long* arg_values,
+//                    int threshold_begin_id,
+//                    long long threshold,
+//                    unsigned char flags)
+#define TRACE_EVENT_API_ADD_TRACE_EVENT_EXPLICIT \

[nduca, 2012/12/04 05:09:38]

what requires this one?

[dsinclair, 2012/12/04 15:02:38]

It's used on line 992 in AddTraceEventExplicit().

+    base::debug::TraceLog::GetInstance()->AddTraceEventExplicit
+
 ////////////////////////////////////////////////////////////////////////////////
 
 // Implementation detail: trace event macros create temporary variables
@@ -638,6 +668,23 @@
       } \
     } while (0)
 
+// Implementation detail: internal macro to create static category and add
+// event if the category is enabled.
+#define INTERNAL_TRACE_EVENT_ADD_EXPLICIT(phase, category, name, \
+        at, id, flags, ...) \
+    do { \
+      INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category); \
+      if (*INTERNAL_TRACE_EVENT_UID(catstatic)) { \
+        unsigned char trace_event_flags = flags | TRACE_EVENT_FLAG_HAS_ID; \
+        trace_event_internal::TraceID trace_event_trace_id( \
+            id, &trace_event_flags); \
+        trace_event_internal::AddTraceEventExplicit( \
+            phase, INTERNAL_TRACE_EVENT_UID(catstatic), \
+            name, at, trace_event_trace_id.data(), \
+            trace_event_flags, ##__VA_ARGS__); \
+      } \
+    } while (0)
+
 // Implementation detail: internal macro to create static category and add begin
 // event if the category is enabled. Also adds the end event when the scope
 // ends.
@@ -930,6 +977,17 @@ static inline int AddTraceEvent(char phase,
       kNoThreshholdBeginId, kNoThresholdValue, flags);
 }
 
+static inline int AddTraceEventExplicit(char phase,
+                                        const unsigned char* category_enabled,
+                                        const char* name,
+                                        int64 timestamp,
+                                        unsigned long long id,
+                                        unsigned char flags) {
+  return TRACE_EVENT_API_ADD_TRACE_EVENT_EXPLICIT(
+      phase, category_enabled, name, timestamp, id, kZeroNumArgs,
+      NULL, NULL, NULL, kNoThreshholdBeginId, kNoThresholdValue, flags);
+}
+
 // Used by TRACE_EVENTx macro. Do not use directly.
 class BASE_EXPORT TraceEndOnScopeClose {
  public: