Add mutex when accessing concurrent recompilation output queue.

src/optimizing-compiler-thread.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 56 matching lines @@
         if (FLAG_trace_concurrent_recompilation) {
           time_spent_total_ = total_timer.Elapsed();
         }
         stop_semaphore_.Signal();
         return;
       case FLUSH:
         // The main thread is blocked, waiting for the stop semaphore.
         { AllowHandleDereference allow_handle_dereference;
           FlushInputQueue(true);
         }
-        Release_Store(&queue_length_, static_cast<AtomicWord>(0));
         Release_Store(&stop_thread_, static_cast<AtomicWord>(CONTINUE));
         stop_semaphore_.Signal();
         // Return to start of consumer loop.
         continue;
     }
 
     ElapsedTimer compiling_timer;
     if (FLAG_trace_concurrent_recompilation) compiling_timer.Start();
 
     CompileNext();
@@ skipping 19 matching lines @@
 
   // The function may have already been optimized by OSR.  Simply continue.
   // Use a mutex to make sure that functions marked for install
   // are always also queued.
   if (!optimizing_compiler->info()->osr_ast_id().IsNone()) {
     ASSERT(FLAG_concurrent_osr);
     LockGuard<Mutex> access_osr_lists(&osr_list_mutex_);
     osr_candidates_.RemoveElement(optimizing_compiler);
     ready_for_osr_.Add(optimizing_compiler);
   } else {
+    LockGuard<Mutex> access_queue(&queue_mutex_);
     output_queue_.Enqueue(optimizing_compiler);
     isolate_->stack_guard()->RequestInstallCode();
   }
 }
 
 
 void OptimizingCompilerThread::FlushInputQueue(bool restore_function_code) {
   OptimizingCompiler* optimizing_compiler;
   // The optimizing compiler is allocated in the CompilationInfo's zone.
   while (input_queue_.Dequeue(&optimizing_compiler)) {
     // This should not block, since we have one signal on the input queue
     // semaphore corresponding to each element in the input queue.
     input_queue_semaphore_.Wait();
     CompilationInfo* info = optimizing_compiler->info();
     if (restore_function_code) {
       Handle<JSFunction> function = info->closure();
       function->ReplaceCode(function->shared()->code());
     }
     delete info;
   }
+  Release_Store(&queue_length_, static_cast<AtomicWord>(0));
+
+  LockGuard<Mutex> access_osr_lists(&osr_list_mutex_);
+  osr_candidates_.Clear();
 }
 
 
 void OptimizingCompilerThread::FlushOutputQueue(bool restore_function_code) {
   OptimizingCompiler* optimizing_compiler;
   // The optimizing compiler is allocated in the CompilationInfo's zone.
-  while (output_queue_.Dequeue(&optimizing_compiler)) {
+  while (true) {
+    { LockGuard<Mutex> access_queue(&queue_mutex_);
+      if (!output_queue_.Dequeue(&optimizing_compiler)) break;
+    }
     CompilationInfo* info = optimizing_compiler->info();
     if (restore_function_code) {
       Handle<JSFunction> function = info->closure();
       function->ReplaceCode(function->shared()->code());
     }
     delete info;
   }
 
-  osr_candidates_.Clear();
   RemoveStaleOSRCandidates(0);
 }
 
 
 void OptimizingCompilerThread::Flush() {
   ASSERT(!IsOptimizerThread());
   Release_Store(&stop_thread_, static_cast<AtomicWord>(FLUSH));
   input_queue_semaphore_.Signal();
   stop_semaphore_.Wait();
   FlushOutputQueue(true);
@@ skipping 26 matching lines @@
     PrintF("[COSR hit rate %d / %d]\n", osr_hits_, osr_attempts_);
   }
 
   Join();
 }
 
 
 void OptimizingCompilerThread::InstallOptimizedFunctions() {
   ASSERT(!IsOptimizerThread());
   HandleScope handle_scope(isolate_);
+
   OptimizingCompiler* compiler;
   while (true) {
-    if (!output_queue_.Dequeue(&compiler)) return;
+    { LockGuard<Mutex> access_queue(&queue_mutex_);
+      if (!output_queue_.Dequeue(&optimizing_compiler)) break;
+    }
     Compiler::InstallOptimizedCode(compiler);
   }
 
   // Remove the oldest OSR candidates that are ready so that we
   // only have limited number of them waiting.
   if (FLAG_concurrent_osr) RemoveStaleOSRCandidates();
 }
 
 
 void OptimizingCompilerThread::QueueForOptimization(
@@ skipping 76 matching lines @@
 #ifdef DEBUG
 bool OptimizingCompilerThread::IsOptimizerThread() {
   if (!FLAG_concurrent_recompilation) return false;
   LockGuard<Mutex> lock_guard(&thread_id_mutex_);
   return ThreadId::Current().ToInteger() == thread_id_;
 }
 #endif
 
 
 } }  // namespace v8::internal