Reland: Add a trace-event for each runtime-stats timer (CL 2052523002)

src/tracing/trace-event.h

 // Copyright 2015 the V8 project 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 SRC_TRACING_TRACE_EVENT_H_
 #define SRC_TRACING_TRACE_EVENT_H_
 
 #include <stddef.h>
 
 #include "base/trace_event/common/trace_event_common.h"
@@ skipping 115 matching lines @@
 // Set the duration field of a COMPLETE trace event.
 // void TRACE_EVENT_API_UPDATE_TRACE_EVENT_DURATION(
 //     const uint8_t* category_group_enabled,
 //     const char* name,
 //     uint64_t id)
 #define TRACE_EVENT_API_UPDATE_TRACE_EVENT_DURATION             \
   v8::internal::tracing::TraceEventHelper::GetCurrentPlatform() \
       ->UpdateTraceEventDuration
 
 // Defines atomic operations used internally by the tracing system.
+#define TRACE_EVENT_API_ATOMIC_BYTE v8::base::Atomic8
 #define TRACE_EVENT_API_ATOMIC_WORD v8::base::AtomicWord
 #define TRACE_EVENT_API_ATOMIC_LOAD(var) v8::base::NoBarrier_Load(&(var))
 #define TRACE_EVENT_API_ATOMIC_STORE(var, value) \
   v8::base::NoBarrier_Store(&(var), (value))
 
 // The thread buckets for the sampling profiler.
 extern TRACE_EVENT_API_ATOMIC_WORD g_trace_state[3];
 
 #define TRACE_EVENT_API_THREAD_BUCKET(thread_bucket) \
   g_trace_state[thread_bucket]
@@ skipping 441 matching lines @@
   }
 
  private:
   const char* previous_state_;
 };
 
 }  // namespace tracing
 }  // namespace internal
 }  // namespace v8
 
+// V8 Specific macros
+
+// Runtime calls happen at a high frequency, the following set of macros
+// minimizes the tracing overhead of those calls. A global variable is set
+// when top level V8 API is called, and checked per runtime call.
+extern TRACE_EVENT_API_ATOMIC_BYTE g_runtime_calls_trace_enabled;
+
+#define TRACE_IS_RUNTIME_CALLS_TRACING_ENABLED() \
+  TRACE_EVENT_API_ATOMIC_LOAD(g_runtime_calls_trace_enabled)
+
+#define TRACE_CHECK_AND_SET_RUNTIME_CALLS_TRACING()                            \
+  do {                                                                         \
+    INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(                                    \
+        TRACE_DISABLED_BY_DEFAULT("v8.runtime"));                              \
+    TRACE_EVENT_API_ATOMIC_STORE(g_runtime_calls_trace_enabled,                \
+        INTERNAL_TRACE_EVENT_CATEGORY_GROUP_ENABLED_FOR_RECORDING_MODE() ? 1   \
+                                                                         : 0); \
+  } while (0)
+
+#define TRACE_RUNTIME_CALL(name)                                               \
+  do {                                                                         \
+    if (V8_UNLIKELY(TRACE_IS_RUNTIME_CALLS_TRACING_ENABLED())) {               \
+      INTERNAL_TRACE_EVENT_ADD_SCOPED(TRACE_DISABLED_BY_DEFAULT("v8.runtime"), \
+                                      name);                                   \
+    }                                                                          \
+  } while (0)
+
 #endif  // SRC_TRACING_TRACE_EVENT_H_