[Compiler] Track Ignition background compilation separately in RuntimeStats.

src/interpreter/interpreter.cc

Index: src/interpreter/interpreter.cc
diff --git a/src/interpreter/interpreter.cc b/src/interpreter/interpreter.cc
index 5b484cca78e1558c880bbf89b5f219243eb04ee6..5642a2c08e9c17ea1eb17e48fdb42184a20cd78c 100644
--- a/src/interpreter/interpreter.cc
+++ b/src/interpreter/interpreter.cc
@@ -44,6 +44,7 @@ class InterpreterCompilationJob final : public CompilationJob {
   BytecodeGenerator* generator() { return &generator_; }
 
   BytecodeGenerator generator_;
+  RuntimeCallStats* runtime_call_stats_;
 
   DISALLOW_COPY_AND_ASSIGN(InterpreterCompilationJob);
 };
@@ -160,7 +161,9 @@ int Interpreter::InterruptBudget() {
 }
 
 InterpreterCompilationJob::InterpreterCompilationJob(CompilationInfo* info)
-    : CompilationJob(info->isolate(), info, "Ignition"), generator_(info) {}
+    : CompilationJob(info->isolate(), info, "Ignition"),
+      generator_(info),
+      runtime_call_stats_(info->isolate()->counters()->runtime_call_stats()) {}
 
 InterpreterCompilationJob::Status InterpreterCompilationJob::PrepareJobImpl() {
   CodeGenerator::MakeCodePrologue(info(), "interpreter");
@@ -176,11 +179,14 @@ InterpreterCompilationJob::Status InterpreterCompilationJob::PrepareJobImpl() {
 }
 
 InterpreterCompilationJob::Status InterpreterCompilationJob::ExecuteJobImpl() {
-  // TODO(5203): These timers aren't thread safe, move to using the CompilerJob
-  // timers.
-  RuntimeCallTimerScope runtimeTimer(info()->isolate(),
-                                     &RuntimeCallStats::CompileIgnition);
-  TimerEventScope<TimerEventCompileIgnition> timer(info()->isolate());
+  if (FLAG_runtime_stats && executed_on_background_thread()) {
+    // Create separate runtime stats for background compilation.
+    runtime_call_stats_ = new (info()->zone()) RuntimeCallStats();

[jochen (gone - plz use gerrit), 2016/12/16 10:47:38]

this allocates a potentially pretty large object even though we just need one
counter. Should we rather just instantiate the one counter?

[Camillo Bruni, 2016/12/16 11:42:54]

I think we initially discussed to do exactly that, using a separate timer and
directly sum up the values in the correct counter
(RuntimeCallStats::CompileBackgroundIgnition).

[rmcilroy, 2016/12/16 23:48:05]

Yeah good point. I was basing this on the approach taken by the background
parser, but have changed to use a separate counter (with a special TimerScope to
ensure we still correctly nest timers if running on the main thread). If we are
worried about allocating a large object on every compile then we should probably
adapt the approach taken in the parser too, since it will end up running as
often as this code with the CompilerDispatcher.

+  }
+  RuntimeCallTimerScope runtimeTimer(
+      runtime_call_stats_, executed_on_background_thread()
+                               ? &RuntimeCallStats::CompileBackgroundIgnition
+                               : &RuntimeCallStats::CompileIgnition);
   TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"), "V8.CompileIgnition");

[Camillo Bruni, 2016/12/16 09:25:05]

Please add: TODO(lpy): add support for background compilation RCS trace
see https://codereview.chromium.org/2559403002

[rmcilroy, 2016/12/16 23:48:05]

Done.

 
   generator()->GenerateBytecode(stack_limit());
@@ -192,6 +198,19 @@ InterpreterCompilationJob::Status InterpreterCompilationJob::ExecuteJobImpl() {
 }
 
 InterpreterCompilationJob::Status InterpreterCompilationJob::FinalizeJobImpl() {
+  // Add background runtime call stats.
+  if (executed_on_background_thread() &&
+      FLAG_runtime_stats ==
+          v8::tracing::TracingCategoryObserver::ENABLED_BY_NATIVE) {
+    info()->isolate()->counters()->runtime_call_stats()->Add(
+        runtime_call_stats_);
+    // Reset runtime_call_stats_.
+    runtime_call_stats_ = info()->isolate()->counters()->runtime_call_stats();
+  }
+
+  RuntimeCallTimerScope runtimeTimer(
+      runtime_call_stats_, &RuntimeCallStats::CompileIgnitionFinalization);
+
   Handle<BytecodeArray> bytecodes = generator()->FinalizeBytecode(isolate());
   if (generator()->HasStackOverflow()) {
     return FAILED;