- Add and enable concurrent sweeper.

runtime/vm/pages.h

 // 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.
 
 #ifndef VM_PAGES_H_
 #define VM_PAGES_H_
 
 #include "vm/freelist.h"
 #include "vm/globals.h"
 #include "vm/ring_buffer.h"
@@ skipping 278 matching lines @@
 
   uword TryAllocateDataLocked(intptr_t size, GrowthPolicy growth_policy) {
     bool is_protected = false;
     bool is_locked = true;
     return TryAllocateInternal(size,
                                HeapPage::kData,
                                growth_policy,
                                is_protected, is_locked);
   }
 
+  Monitor* tasks_lock() const { return tasks_lock_; }
+  intptr_t tasks() const { return tasks_; }
+  void set_tasks(intptr_t val) { tasks_ = val; }

[koda, 2014/08/26 23:34:49]

ASSERT(tasks_ >= 0);

Also consider just having increment/decrement/has_tasks methods.

[Ivan Posva, 2014/08/27 01:00:22]

Done.

+
  private:
   // Ids for time and data records in Heap::GCStats.
   enum {
     // Time
     kMarkObjects = 0,
     kResetFreeLists = 1,
     kSweepPages = 2,
     kSweepLargePages = 3,
     // Data
     kGarbageRatio = 0,
     kGCTimeFraction = 1,
     kPageGrowth = 2,
     kAllowedGrowth = 3
   };
 
-  Monitor* tasks_lock() const { return tasks_lock_; }
-  intptr_t tasks() const { return tasks_; }
-  void set_tasks(intptr_t val) { tasks_ = val; }
-
   static const intptr_t kAllocatablePageSize = 64 * KB;
 
   uword TryAllocateInternal(intptr_t size,
                             HeapPage::PageType type,
                             GrowthPolicy growth_policy,
                             bool is_protected,
                             bool is_locked);
   HeapPage* AllocatePage(HeapPage::PageType type);
   void FreePage(HeapPage* page, HeapPage* previous_page);
   HeapPage* AllocateLargePage(intptr_t size, HeapPage::PageType type);
   void TruncateLargePage(HeapPage* page, intptr_t new_object_size_in_bytes);
   void FreeLargePage(HeapPage* page, HeapPage* previous_page);
   void FreePages(HeapPage* pages);
   HeapPage* NextPageAnySize(HeapPage* page) const {
-    ASSERT(pages_tail_ == NULL || pages_tail_->next() == NULL);
-    return page == pages_tail_ ? large_pages_ : page->next();
+    ASSERT((pages_tail_ == NULL) || (pages_tail_->next() == NULL));
+    ASSERT((exec_pages_tail_ == NULL) || (exec_pages_tail_->next() == NULL));
+    if (page == pages_tail_) {
+      return (exec_pages_ != NULL) ? exec_pages_ : large_pages_;
+    }
+    return page == exec_pages_tail_ ? large_pages_ : page->next();
   }
 
   static intptr_t LargePageSizeInWordsFor(intptr_t size);
 
   bool CanIncreaseCapacityInWords(intptr_t increase_in_words) {
     ASSERT(CapacityInWords() <= max_capacity_in_words_);
     return increase_in_words <= (max_capacity_in_words_ - CapacityInWords());
   }
 
   FreeList freelist_[HeapPage::kNumPageTypes];
 
   Heap* heap_;
 
+  Mutex* pages_lock_;
   HeapPage* pages_;
   HeapPage* pages_tail_;
+  HeapPage* exec_pages_;
+  HeapPage* exec_pages_tail_;
   HeapPage* large_pages_;

[koda, 2014/08/26 23:34:49]

Can large pages be executable?

[Ivan Posva, 2014/08/27 01:00:22]

Yes, large pages survive as a mixed class list.

 
   // Various sizes being tracked for this generation.
   intptr_t max_capacity_in_words_;
   SpaceUsage usage_;
 
   // Keep track of running MarkSweep tasks.
   Monitor* tasks_lock_;
   intptr_t tasks_;
 
   PageSpaceController page_space_controller_;
 
   int64_t gc_time_micros_;
   intptr_t collections_;
 
   friend class PageSpaceController;
+  friend class SweeperTask;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(PageSpace);
 };
 
 }  // namespace dart
 
 #endif  // VM_PAGES_H_