[counters] Making counter properly reentrant.

src/counters.h

 // Copyright 2012 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 V8_COUNTERS_H_
 #define V8_COUNTERS_H_
 
 #include "include/v8.h"
 #include "src/allocation.h"
 #include "src/base/platform/elapsed-timer.h"
@@ skipping 683 matching lines @@
   SC(lo_space_bytes_used, V8.MemoryLoSpaceBytesUsed)                           \
   SC(turbo_escape_allocs_replaced, V8.TurboEscapeAllocsReplaced)               \
   SC(crankshaft_escape_allocs_replaced, V8.CrankshaftEscapeAllocsReplaced)     \
   SC(turbo_escape_loads_replaced, V8.TurboEscapeLoadsReplaced)                 \
   SC(crankshaft_escape_loads_replaced, V8.CrankshaftEscapeLoadsReplaced)       \
   /* Total code size (including metadata) of baseline code or bytecode. */     \
   SC(total_baseline_code_size, V8.TotalBaselineCodeSize)                       \
   /* Total count of functions compiled using the baseline compiler. */         \
   SC(total_baseline_compile_count, V8.TotalBaselineCompileCount)
 
-typedef struct RuntimeCallCounter {
+struct RuntimeCallCounter {
+  explicit RuntimeCallCounter(const char* name) : name(name) {}
+  void Reset();
+
+  const char* name;
   int64_t count = 0;
   base::TimeDelta time;
-  RuntimeCallCounter* parent_counter;
+};
 
-  void Reset();
-} RuntimeCallCounter;
+// TimerLink is used to keep track of the stack of currently active timers used
+// for RuntimeCallCounter.
+class TimerLink {
+ public:
+  TimerLink(RuntimeCallCounter* counter, TimerLink* parent)
+      : counter_(counter), parent_(parent) {}
+
+  inline void Start() {
+    timer_.Start();
+    counter_->count++;
+  }
+
+  inline TimerLink* Stop() {
+    base::TimeDelta delta = timer_.Elapsed();
+    counter_->time += delta;
+    if (parent_ != NULL) {
+      parent_->AdjustForSubTimer(delta);
+    }
+    return parent_;
+  }
+
+  void AdjustForSubTimer(base::TimeDelta delta) { counter_->time -= delta; }
+
+ private:
+  RuntimeCallCounter* counter_;
+  TimerLink* parent_;
+  base::ElapsedTimer timer_;
+};
 
 struct RuntimeCallStats {
+  // Dummy counter for the unexpected stub miss.
+  RuntimeCallCounter UnexpectedStubMiss = {"UnexpectedStubMiss"};
+  // Counter for runtime callbacks into JavaScript.
+  RuntimeCallCounter RuntimeCallbacks = {"RuntimeCallback"};
 #define CALL_RUNTIME_COUNTER(name, nargs, ressize) \
-  RuntimeCallCounter Runtime_##name;
+  RuntimeCallCounter Runtime_##name = {#name};
   FOR_EACH_INTRINSIC(CALL_RUNTIME_COUNTER)
 #undef CALL_RUNTIME_COUNTER
-#define CALL_BUILTIN_COUNTER(name, type) RuntimeCallCounter Builtin_##name;
+#define CALL_BUILTIN_COUNTER(name, type) \
+  RuntimeCallCounter Builtin_##name = {#name};
   BUILTIN_LIST_C(CALL_BUILTIN_COUNTER)
 #undef CALL_BUILTIN_COUNTER
 
-  // Dummy counter for the unexpected stub miss.
-  RuntimeCallCounter UnexpectedStubMiss;
   // Counter to track recursive time events.
-  RuntimeCallCounter* current_counter;
+  TimerLink* current_timer_link_;
 
   // Starting measuring the time for a function. This will establish the
   // connection to the parent counter for properly calculating the own times.
   void Enter(RuntimeCallCounter* counter);
   // Leave a scope for a measured runtime function. This will properly add
   // the time delta to the current_counter and subtract the delta from its
   // parent.
-  void Leave(base::TimeDelta time);
+  void Leave();
 
   void Reset();
   void Print(std::ostream& os);
 
   RuntimeCallStats() { Reset(); }
 };
 
 // This file contains all the v8 counters that are in use.
 class Counters {
  public:
@@ skipping 172 matching lines @@
 
   explicit Counters(Isolate* isolate);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(Counters);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COUNTERS_H_