Old-gen marking on separate thread

runtime/vm/thread_registry.h

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_THREAD_REGISTRY_H_
 #define VM_THREAD_REGISTRY_H_
 
 #include "vm/globals.h"
 #include "vm/growable_array.h"
 #include "vm/isolate.h"
@@ skipping 30 matching lines @@
   // TODO(koda): Consider adding a scope helper to avoid omitting this call.
   void ResumeAllThreads();
 
   // Indicate that the current thread is at a safepoint, and offer to wait for
   // any pending rendezvous request (if none, returns immediately).
   void CheckSafepoint() {
     MonitorLocker ml(monitor_);
     CheckSafepointLocked();
   }
 
-  bool RestoreStateTo(Thread* thread, Thread::State* state) {
+  bool RestoreStateTo(Thread* thread, Thread::State* state,
+                      bool bypass_safepoint) {
     MonitorLocker ml(monitor_);
     // Wait for any rendezvous in progress.
-    while (in_rendezvous_) {
+    while (!bypass_safepoint && in_rendezvous_) {
       ml.Wait(Monitor::kNoTimeout);
     }
     Entry* entry = FindEntry(thread);
     if (entry != NULL) {
       Thread::State st = entry->state;
       // TODO(koda): Support same thread re-entering same isolate with
       // Dart frames in between. For now, just assert it doesn't happen.
       if (st.top_exit_frame_info != thread->top_exit_frame_info()) {
         ASSERT(thread->top_exit_frame_info() == 0 ||
                thread->top_exit_frame_info() > st.top_exit_frame_info);
@@ skipping 11 matching lines @@
     new_entry.thread = thread;
     new_entry.scheduled = true;
 #if defined(DEBUG)
     // State field is not in use, so zap it.
     memset(&new_entry.state, 0xda, sizeof(new_entry.state));
 #endif
     entries_.Add(new_entry);
     return false;
   }
 
-  void SaveStateFrom(Thread* thread, const Thread::State& state) {
+  void SaveStateFrom(Thread* thread, const Thread::State& state,
+                     bool bypass_safepoint) {
     MonitorLocker ml(monitor_);
     Entry* entry = FindEntry(thread);
     ASSERT(entry != NULL);
     ASSERT(entry->scheduled);
     entry->scheduled = false;
     entry->state = state;
-    if (in_rendezvous_) {
+    if (!bypass_safepoint && in_rendezvous_) {
       // Don't wait for this thread.
       ASSERT(remaining_ > 0);
       if (--remaining_ == 0) {
         ml.NotifyAll();
       }
     }
   }
 
   bool Contains(Thread* thread) {
     MonitorLocker ml(monitor_);
@@ skipping 91 matching lines @@
   intptr_t remaining_;    // Number of threads yet to reach their safepoint.
   int64_t round_;         // Counter, to prevent missing updates to remaining_
                           // (see comments in CheckSafepointLocked).
 
   DISALLOW_COPY_AND_ASSIGN(ThreadRegistry);
 };
 
 }  // namespace dart
 
 #endif  // VM_THREAD_REGISTRY_H_