Implement committed physical memory stats for Linux.

src/spaces-inl.h

 // Copyright 2011 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 196 matching lines @@
       if (chunk->Contains(addr)) {
         return chunk;
       }
     }
   }
   UNREACHABLE();
   return NULL;
 }
 
 
+void MemoryChunk::UpdateHighWaterMark(Address mark) {
+  if (mark == NULL) return;
+  // Need to subtract one from the mark because when a chunk is full the
+  // top points to the next address after the chunk, which effectively belongs
+  // to another chunk. See the comment to Page::FromAllocationTop.
+  MemoryChunk* chunk = MemoryChunk::FromAddress(mark - 1);
+  int new_mark = static_cast<int>(mark - chunk->address());
+  if (new_mark > chunk->high_water_mark_) {
+    chunk->high_water_mark_ = new_mark;
+  }
+}
+
+
 PointerChunkIterator::PointerChunkIterator(Heap* heap)
     : state_(kOldPointerState),
       old_pointer_iterator_(heap->old_pointer_space()),
       map_iterator_(heap->map_space()),
       lo_iterator_(heap->lo_space()) { }
 
 
 Page* Page::next_page() {
   ASSERT(next_chunk()->owner() == owner());
   return static_cast<Page*>(next_chunk());
@@ skipping 132 matching lines @@
   Map* map = object->map();
   Heap* heap = object->GetHeap();
   return map == heap->raw_unchecked_free_space_map()
       || map == heap->raw_unchecked_one_pointer_filler_map()
       || map == heap->raw_unchecked_two_pointer_filler_map();
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_INL_H_