Safepoint interface and unit tests.

runtime/vm/store_buffer.cc

 // Copyright (c) 2012, 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/store_buffer.h"
 
 #include "platform/assert.h"
 #include "vm/lockers.h"
 #include "vm/runtime_entry.h"
 
@@ skipping 60 matching lines @@
     MutexLocker ml(mutex_);
     full_.Push(block);
   } else if (block->IsEmpty()) {
     MutexLocker ml(global_mutex_);
     global_empty_->Push(block);
     TrimGlobalEmpty();
   } else {
     MutexLocker ml(mutex_);
     partial_.Push(block);
   }
-  if (check_threshold) {
+  if (check_threshold && Overflowed()) {
     MutexLocker ml(mutex_);
-    CheckThresholdNonEmpty();
+    Isolate* isolate = Isolate::Current();
+    // Sanity check: it makes no sense to schedule the GC in another isolate.
+    // (If Isolate ever gets multiple store buffers, we should avoid this
+    // coupling by passing in an explicit callback+parameter at construction.)
+    ASSERT(isolate->store_buffer() == this);
+    isolate->ScheduleInterrupts(Isolate::kVMInterrupt);
   }
 }
 
 
 StoreBufferBlock* StoreBuffer::PopBlock() {
   {
     MutexLocker ml(mutex_);
     if (!partial_.IsEmpty()) {
       return partial_.Pop();
     }
@@ skipping 38 matching lines @@
 
 
 void StoreBuffer::List::Push(StoreBufferBlock* block) {
   ASSERT(block->next_ == NULL);
   block->next_ = head_;
   head_ = block;
   ++length_;
 }
 
 
-void StoreBuffer::CheckThresholdNonEmpty() {
-  DEBUG_ASSERT(mutex_->IsOwnedByCurrentThread());
-  if (full_.length() + partial_.length() > kMaxNonEmpty) {
-    Isolate* isolate = Isolate::Current();
-    // Sanity check: it makes no sense to schedule the GC in another isolate.
-    // (If Isolate ever gets multiple store buffers, we should avoid this
-    // coupling by passing in an explicit callback+parameter at construction.)
-    ASSERT(isolate->store_buffer() == this);
-    isolate->ScheduleInterrupts(Isolate::kStoreBufferInterrupt);
-  }
+bool StoreBuffer::Overflowed() {
+  MutexLocker ml(mutex_);
+  return (full_.length() + partial_.length()) > kMaxNonEmpty;
 }
 
 
 void StoreBuffer::TrimGlobalEmpty() {
   DEBUG_ASSERT(global_mutex_->IsOwnedByCurrentThread());
   while (global_empty_->length() > kMaxGlobalEmpty) {
     delete global_empty_->Pop();
   }
 }
 
 }  // namespace dart