Replace blink::WebDiscardableMemory with base::DiscardableMemory.

third_party/WebKit/Source/platform/PurgeableVector.cpp

 /*
  * Copyright (C) 2014 Google Inc. 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
@@ skipping 12 matching lines @@
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "platform/PurgeableVector.h"
 
-#include "public/platform/Platform.h"
-#include "public/platform/WebDiscardableMemory.h"
+#include "base/memory/discardable_memory.h"
+#include "base/memory/discardable_memory_allocator.h"
 #include "public/platform/WebProcessMemoryDump.h"
 #include "wtf/Assertions.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
+#include "wtf/text/StringUTF8Adaptor.h"
 #include "wtf/text/WTFString.h"
 
 #include <cstring>
+#include <string>
+#include <utility>
 
 namespace blink {
 
-// WebDiscardableMemory allocations are expensive and page-grained. We only use
+// DiscardableMemory allocations are expensive and page-grained. We only use
 // them when there's a reasonable amount of memory to be saved by the OS
 // discarding the memory.
 static const size_t minimumDiscardableAllocationSize = 4 * 4096;
 
 PurgeableVector::PurgeableVector(PurgeableOption purgeable)
     : m_discardableCapacity(0)
     , m_discardableSize(0)
     , m_isPurgeable(purgeable == Purgeable)
     , m_locksCount(1) // The buffer is locked at creation.
 {
@@ skipping 21 matching lines @@
         m_vector.reserveCapacity(capacity);
     }
 
     moveDataFromDiscardableToVector();
 }
 
 void PurgeableVector::onMemoryDump(const String& dumpName, WebProcessMemoryDump* memoryDump) const
 {
     ASSERT(!(m_discardable && m_vector.size()));
     if (m_discardable) {
-        WebMemoryAllocatorDump* dump = m_discardable->createMemoryAllocatorDump(dumpName, memoryDump);
+        StringUTF8Adaptor utf8DumpName(dumpName);
+        WebMemoryAllocatorDump* dump = memoryDump->createDiscardableMemoryAllocatorDump(
+            std::string(utf8DumpName.data(), utf8DumpName.length()), m_discardable.get());

[esprehn, 2016/03/15 20:43:26]

.asStringPiece().as_string() would work too?

[jbroman, 2016/03/15 23:27:03]

Sure would. It sounds like you prefer .asStringPiece().as_string(), so I'll do
that.

         dump->addScalar("discardable_size", "bytes", m_discardableSize);
     } else if (m_vector.size()) {
         WebMemoryAllocatorDump* dump = memoryDump->createMemoryAllocatorDump(dumpName);
         dump->addScalar("size", "bytes", m_vector.size());
         memoryDump->addSuballocation(dump->guid(), String(WTF::Partitions::kAllocatedObjectPoolName));
     }
 }
 
 void PurgeableVector::moveDataFromDiscardableToVector()
 {
     if (m_discardable) {
         m_vector.append(static_cast<const char*>(m_discardable->data()), m_discardableSize);
         clearDiscardable();
     }
 }
 
 void PurgeableVector::clearDiscardable()
 {
-    m_discardable.clear();
+    m_discardable = nullptr;
     m_discardableCapacity = 0;
     m_discardableSize = 0;
 }
 
 void PurgeableVector::append(const char* data, size_t length)
 {
     ASSERT(isLocked());
 
     if (!m_isPurgeable) {
         m_vector.append(data, length);
@@ skipping 66 matching lines @@
 bool PurgeableVector::lock()
 {
     ++m_locksCount;
     if (m_locksCount > 1)
         return true;
 
     ASSERT(m_locksCount == 1);
     if (!m_discardable)
         return true;
 
-    return m_discardable->lock();
+    return m_discardable->Lock();
 }
 
 void PurgeableVector::unlock()
 {
     ASSERT(isLocked());
     --m_locksCount;
     if (m_locksCount > 0)
         return;
 
     if (!m_vector.isEmpty()) {
         ASSERT(!m_discardable);
         m_isPurgeable = true;
         if (!reservePurgeableCapacity(m_vector.size(), UseExactCapacity))
             return;
     }
 
     if (m_discardable)
-        m_discardable->unlock();
+        m_discardable->Unlock();
 }
 
 bool PurgeableVector::isLocked() const
 {
     ASSERT(m_locksCount >= 0);
     return m_locksCount > 0;
 }
 
 bool PurgeableVector::reservePurgeableCapacity(size_t capacity, PurgeableAllocationStrategy allocationStrategy)
 {
     ASSERT(m_isPurgeable);
 
     if (m_discardable && m_discardableCapacity >= capacity) {
         ASSERT(!m_vector.capacity());
         return true;
     }
 
     if (capacity < minimumDiscardableAllocationSize)
         return false;
 
     if (allocationStrategy == UseExponentialGrowth)
         capacity = adjustPurgeableCapacity(capacity);
 
-    OwnPtr<WebDiscardableMemory> discardable = adoptPtr(
-        Platform::current()->allocateAndLockDiscardableMemory(capacity));
-    if (!discardable) {
-        // Discardable memory is not supported.
-        m_isPurgeable = false;
-        return false;
-    }
+    scoped_ptr<base::DiscardableMemory> discardable =
+        base::DiscardableMemoryAllocator::GetInstance()->AllocateLockedDiscardableMemory(capacity);
+    ASSERT(discardable);
 
     m_discardableCapacity = capacity;
     // Copy the data that was either in the previous purgeable buffer or in the vector to the new
     // purgeable buffer.
     if (m_discardable) {
         memcpy(discardable->data(), m_discardable->data(), m_discardableSize);
     } else {
         memcpy(discardable->data(), m_vector.data(), m_vector.size());
         m_discardableSize = m_vector.size();
         m_vector.clear();
     }
 
-    m_discardable.swap(discardable);
+    m_discardable = std::move(discardable);
     ASSERT(!m_vector.capacity());
     return true;
 }
 
 size_t PurgeableVector::adjustPurgeableCapacity(size_t capacity) const
 {
     ASSERT(capacity >= minimumDiscardableAllocationSize);
 
     const float growthFactor = 1.5;
     size_t newCapacity = std::max(capacity, static_cast<size_t>(m_discardableCapacity * growthFactor));
 
     // Discardable memory has page-granularity so align to the next page here to minimize
     // fragmentation.
     // Since the page size is only used below to minimize fragmentation it's still safe to use it
     // even if it gets out of sync (e.g. due to the use of huge pages).
     const size_t kPageSize = 4096;
     newCapacity = (newCapacity + kPageSize - 1) & ~(kPageSize - 1);
 
     return std::max(capacity, newCapacity); // Overflow check.
 }
 
 } // namespace blink