Implement safepointing of threads

runtime/vm/scavenger.cc

 // Copyright (c) 2011, 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.
 
 #include "vm/scavenger.h"
 
 #include <algorithm>
 #include <map>
 #include <utility>
 
 #include "vm/dart.h"
 #include "vm/dart_api_state.h"
 #include "vm/isolate.h"
 #include "vm/lockers.h"
 #include "vm/object.h"
 #include "vm/object_id_ring.h"
+#include "vm/safepoint.h"
 #include "vm/stack_frame.h"
 #include "vm/store_buffer.h"
 #include "vm/thread_registry.h"
 #include "vm/verified_memory.h"
 #include "vm/verifier.h"
 #include "vm/visitor.h"
 #include "vm/weak_table.h"
 
 namespace dart {
 
@@ skipping 415 matching lines @@
   } else {
     return old_size_in_words;
   }
 }
 
 
 SemiSpace* Scavenger::Prologue(Isolate* isolate, bool invoke_api_callbacks) {
   if (invoke_api_callbacks && (isolate->gc_prologue_callback() != NULL)) {
     (isolate->gc_prologue_callback())();
   }
-  isolate->thread_registry()->PrepareForGC();
+  isolate->PrepareForGC();
   // Flip the two semi-spaces so that to_ is always the space for allocating
   // objects.
   SemiSpace* from = to_;
   to_ = SemiSpace::New(NewSizeInWords(from->size_in_words()));
   if (to_ == NULL) {
     // TODO(koda): We could try to recover (collect old space, wait for another
     // isolate to finish scavenge, etc.).
     FATAL("Out of memory.\n");
   }
   UpdateMaxHeapCapacity();
@@ skipping 293 matching lines @@
 }
 
 
 void Scavenger::Scavenge(bool invoke_api_callbacks) {
   Isolate* isolate = heap_->isolate();
   // Ensure that all threads for this isolate are at a safepoint (either stopped
   // or in native code). If two threads are racing at this point, the loser
   // will continue with its scavenge after waiting for the winner to complete.
   // TODO(koda): Consider moving SafepointThreads into allocation failure/retry
   // logic to avoid needless collections.
-  isolate->thread_registry()->SafepointThreads();
+  SafepointOperationScope safepoint_scope(Thread::Current());
 
   // Scavenging is not reentrant. Make sure that is the case.
   ASSERT(!scavenging_);
   scavenging_ = true;
 
   PageSpace* page_space = heap_->old_space();
   NoSafepointScope no_safepoints;
 
   // TODO(koda): Make verification more compatible with concurrent sweep.
   if (FLAG_verify_before_gc && !FLAG_concurrent_sweep) {
@@ skipping 39 matching lines @@
   // TODO(koda): Make verification more compatible with concurrent sweep.
   if (FLAG_verify_after_gc && !FLAG_concurrent_sweep) {
     OS::PrintErr("Verifying after Scavenge...");
     heap_->Verify(kForbidMarked);
     OS::PrintErr(" done.\n");
   }
 
   // Done scavenging. Reset the marker.
   ASSERT(scavenging_);
   scavenging_ = false;
-
-  isolate->thread_registry()->ResumeAllThreads();
 }
 
 
 void Scavenger::WriteProtect(bool read_only) {
   ASSERT(!scavenging_);
   to_->WriteProtect(read_only);
 }
 
 
 void Scavenger::PrintToJSONObject(JSONObject* object) const {
@@ skipping 28 matching lines @@
 }
 
 
 void Scavenger::FreeExternal(intptr_t size) {
   ASSERT(size >= 0);
   external_size_ -= size;
   ASSERT(external_size_ >= 0);
 }
 
 }  // namespace dart