1 // Copyright 2016 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "src/conversions-inl.h" 6 #include "src/heap/array-buffer-tracker.h" 7 #include "src/heap/heap.h" 8 #include "src/objects.h" 9 10 namespace v8 { 11 namespace internal { 12 13 void ArrayBufferTracker::RegisterNew(Heap* heap, JSArrayBuffer* buffer) { 14 void* data = buffer->backing_store(); 15 if (!data) return; 16 17 size_t length = NumberToSize(buffer->byte_length()); 18 Page* page = Page::FromAddress(buffer->address()); 19 { 20 base::LockGuard<base::Mutex> guard(page->mutex()); 21 LocalArrayBufferTracker* tracker = page->local_tracker(); 22 if (tracker == nullptr) { 23 page->AllocateLocalTracker(); 24 tracker = page->local_tracker(); 25 } 26 DCHECK_NOT_NULL(tracker); 27 tracker->Add(buffer, length); 28 } 29 // We may go over the limit of externally allocated memory here. We call the 30 // api function to trigger a GC in this case. 31 reinterpret_cast<v8::Isolate*>(heap->isolate()) 32 ->AdjustAmountOfExternalAllocatedMemory(length); 33 } 34 35 void ArrayBufferTracker::Unregister(Heap* heap, JSArrayBuffer* buffer) { 36 void* data = buffer->backing_store(); 37 if (!data) return; 38 39 Page* page = Page::FromAddress(buffer->address()); 40 size_t length = 0; 41 { 42 base::LockGuard<base::Mutex> guard(page->mutex()); 43 LocalArrayBufferTracker* tracker = page->local_tracker(); 44 DCHECK_NOT_NULL(tracker); 45 length = tracker->Remove(buffer); 46 } 47 heap->update_external_memory(-static_cast<intptr_t>(length)); 48 } 49 50 void LocalArrayBufferTracker::Add(Key key, const Value& value) { 51 auto ret = array_buffers_.insert(std::make_pair(key, value)); 52 USE(ret); 53 // Check that we indeed inserted a new value and did not overwrite an existing 54 // one (which would be a bug). 55 DCHECK(ret.second); 56 } 57 58 LocalArrayBufferTracker::Value LocalArrayBufferTracker::Remove(Key key) { 59 TrackingData::iterator it = array_buffers_.find(key); 60 // Check that we indeed find a key to remove. 61 DCHECK(it != array_buffers_.end()); 62 Value value = it->second; 63 array_buffers_.erase(it); 64 return value; 65 } 66 67 } // namespace internal 68 } // namespace v8 69
