Log event start and event end separately when using --log-timer-events.

R=haraken@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/12040075

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13529 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/counters.cc

@@ -77,10 +77,13 @@ void* Histogram::CreateHistogram() const {
 
 // Start the timer.
 void HistogramTimer::Start() {
-  if (histogram_.Enabled() || FLAG_log_internal_timer_events) {
+  if (histogram_.Enabled()) {
     stop_time_ = 0;
     start_time_ = OS::Ticks();
   }
+  if (FLAG_log_internal_timer_events) {
+    LOG(Isolate::Current(), TimerEvent(Logger::START, histogram_.name_));
+  }
 }
 
 // Stop the timer and record the results.
@@ -92,8 +95,7 @@ void HistogramTimer::Stop() {
     histogram_.AddSample(milliseconds);
   }
   if (FLAG_log_internal_timer_events) {
-    LOG(Isolate::Current(),
-        TimerEvent(histogram_.name_, start_time_, OS::Ticks()));
+    LOG(Isolate::Current(), TimerEvent(Logger::END, histogram_.name_));
   }
 }
 

src/log.cc

@@ -633,46 +633,30 @@ void Logger::SharedLibraryEvent(const wchar_t* library_path,
 }
 
 
-void Logger::TimerEvent(const char* name, int64_t start, int64_t end) {
+void Logger::TimerEvent(StartEnd se, const char* name) {
   if (!log_->IsEnabled()) return;
   ASSERT(FLAG_log_internal_timer_events);
   LogMessageBuilder msg(this);
-  int since_epoch = static_cast<int>(start - epoch_);
-  int pause_time = static_cast<int>(end - start);
-  msg.Append("timer-event,\"%s\",%ld,%ld\n", name, since_epoch, pause_time);
+  int since_epoch = static_cast<int>(OS::Ticks() - epoch_);
+  const char* format = (se == START) ? "timer-event-start,\"%s\",%ld\n"
+                                     : "timer-event-end,\"%s\",%ld\n";
+  msg.Append(format, name, since_epoch);
   msg.WriteToLogFile();
 }
 
 
-void Logger::ExternalSwitch(StateTag old_tag, StateTag new_tag) {
-  if (old_tag != EXTERNAL && new_tag == EXTERNAL) {
-    enter_external_ = OS::Ticks();
-  }
-  if (old_tag == EXTERNAL && new_tag != EXTERNAL && enter_external_ != 0) {
-    TimerEvent("V8.External", enter_external_, OS::Ticks());
-    enter_external_ = 0;
-  }
-}
-
-
 void Logger::EnterExternal() {
-  LOGGER->enter_external_ = OS::Ticks();
+  LOG(ISOLATE, TimerEvent(START, TimerEventScope::v8_external));
 }
 
 
 void Logger::LeaveExternal() {
-  if (enter_external_ == 0) return;
-  Logger* logger = LOGGER;
-  logger->TimerEvent("V8.External", enter_external_, OS::Ticks());
-  logger->enter_external_ = 0;
+  LOG(ISOLATE, TimerEvent(END, TimerEventScope::v8_external));
 }
 
 
-int64_t Logger::enter_external_ = 0;
-
-
-void Logger::TimerEventScope::LogTimerEvent() {
-  LOG(isolate_, TimerEvent(name_, start_, OS::Ticks()));
+void Logger::TimerEventScope::LogTimerEvent(StartEnd se) {
+  LOG(isolate_, TimerEvent(se, name_));
 }
 
 
@@ -683,6 +667,7 @@ const char* Logger::TimerEventScope::v8_recompile_parallel =
 const char* Logger::TimerEventScope::v8_compile_full_code =
     "V8.CompileFullCode";
 const char* Logger::TimerEventScope::v8_execute = "V8.Execute";
+const char* Logger::TimerEventScope::v8_external = "V8.External";
 
 
 void Logger::LogRegExpSource(Handle<JSRegExp> regexp) {

src/log.h

@@ -273,8 +273,9 @@ class Logger {
                           uintptr_t end);
 
   // ==== Events logged by --log-timer-events. ====
-  void TimerEvent(const char* name, int64_t start, int64_t end);
-  void ExternalSwitch(StateTag old_tag, StateTag new_tag);
+  enum StartEnd { START, END };
+
+  void TimerEvent(StartEnd se, const char* name);
 
   static void EnterExternal();
   static void LeaveExternal();
@@ -282,25 +283,25 @@ class Logger {
   class TimerEventScope {
    public:
     TimerEventScope(Isolate* isolate, const char* name)
-        : isolate_(isolate), name_(name), start_(0) {
-      if (FLAG_log_internal_timer_events) start_ = OS::Ticks();
+        : isolate_(isolate), name_(name) {
+      if (FLAG_log_internal_timer_events) LogTimerEvent(START);
     }
 
     ~TimerEventScope() {
-      if (FLAG_log_internal_timer_events) LogTimerEvent();
+      if (FLAG_log_internal_timer_events) LogTimerEvent(END);
     }
 
-    void LogTimerEvent();
+    void LogTimerEvent(StartEnd se);
 
     static const char* v8_recompile_synchronous;
     static const char* v8_recompile_parallel;
     static const char* v8_compile_full_code;
     static const char* v8_execute;
+    static const char* v8_external;
 
    private:
     Isolate* isolate_;
     const char* name_;
-    int64_t start_;
   };
 
   // ==== Events logged by --log-regexp ====
@@ -473,7 +474,6 @@ class Logger {
   Address prev_code_;
 
   int64_t epoch_;
-  static int64_t enter_external_;
 
   friend class CpuProfiler;
 };

src/vm-state-inl.h

@@ -67,8 +67,8 @@ VMState::VMState(Isolate* isolate, StateTag tag)
     LOG(isolate, UncheckedStringEvent("From", StateToString(previous_tag_)));
   }
 
-  if (FLAG_log_timer_events) {
-    LOG(isolate, ExternalSwitch(previous_tag_, tag));
+  if (FLAG_log_timer_events && previous_tag_ != EXTERNAL && tag == EXTERNAL) {
+    LOG(isolate_, EnterExternal());
   }
 
   isolate_->SetCurrentVMState(tag);
@@ -84,8 +84,9 @@ VMState::~VMState() {
         UncheckedStringEvent("To", StateToString(previous_tag_)));
   }
 
-  if (FLAG_log_timer_events) {
-    LOG(isolate_, ExternalSwitch(isolate_->current_vm_state(), previous_tag_));
+  if (FLAG_log_timer_events &&
+      previous_tag_ != EXTERNAL && isolate_->current_vm_state() == EXTERNAL) {
+    LOG(isolate_, LeaveExternal());
   }
 
   isolate_->SetCurrentVMState(previous_tag_);

tools/plot-timer-events

@@ -41,18 +41,25 @@ else
 
   $d8_exec --nocrankshaft --prof --logfile $calibration_log \
        --log-timer-events -e "$calibration_script" > /dev/null
-  t_1=`grep "V8.Execute" $calibration_log  | tail -n1 | awk -F, '{print $4}'`
-  n_1=`grep "timer-event" $calibration_log  | wc -l`
+  t_1_start=`grep "timer-event-start,\"V8.Execute\"" $calibration_log  \
+       | tail -n1 | awk -F, '{print $3}'`
+  t_1_end=`grep "timer-event-end,\"V8.Execute\"" $calibration_log  \
+       | tail -n1 | awk -F, '{print $3}'`
+  n_1=`grep "timer-event\|tick" $calibration_log  | wc -l`
 
   $d8_exec --nocrankshaft --prof --logfile $calibration_log \
        --log-internal-timer-events -e "$calibration_script" > /dev/null
-  t_2=`grep "V8.Execute" $calibration_log  | tail -n1 | awk -F, '{print $4}'`
-  n_2=`grep "timer-event" $calibration_log  | wc -l`
+  t_2_start=`grep "timer-event-start,\"V8.Execute\"" $calibration_log  \
+       | tail -n1 | awk -F, '{print $3}'`
+  t_2_end=`grep "timer-event-end,\"V8.Execute\"" $calibration_log  \
+       | tail -n1 | awk -F, '{print $3}'`
+  n_2=`grep "timer-event\|tick" $calibration_log  | wc -l`
 
   rm $calibration_log
 
   # Overhead in picoseconds.
-  distortion=`echo "1000*($t_1 - $t_2)/($n_1 - $n_2)" | bc`
+  distortion=`echo "1000*(($t_1_end - $t_1_start) - ($t_2_end - $t_2_start)) \
+                    / ($n_1 - $n_2)" | bc`
 fi
 
 if [ -n "$PLOT_RANGE" ]; then