base/memory/discardable_memory_android.cc

   1 // Copyright (c) 2013 The Chromium 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 "base/memory/discardable_memory.h"
   6
   7 #include "base/android/sys_utils.h"
   8 #include "base/basictypes.h"
   9 #include "base/compiler_specific.h"
  10 #include "base/lazy_instance.h"
  11 #include "base/logging.h"
  12 #include "base/memory/discardable_memory_allocator_android.h"
  13 #include "base/memory/discardable_memory_emulated.h"
  14 #include "base/memory/discardable_memory_malloc.h"
  15
  16 namespace base {
  17 namespace {
  18
  19 const char kAshmemAllocatorName[] = "DiscardableMemoryAllocator";
  20
  21 struct DiscardableMemoryAllocatorWrapper {
  22   DiscardableMemoryAllocatorWrapper()
  23       : allocator(kAshmemAllocatorName,
  24                   GetOptimalAshmemRegionSizeForAllocator()) {
  25   }
  26
  27   internal::DiscardableMemoryAllocator allocator;
  28
  29  private:
  30   // Returns 64 MBytes for a 512 MBytes device, 128 MBytes for 1024 MBytes...
  31   static size_t GetOptimalAshmemRegionSizeForAllocator() {
  32     // Note that this may do some I/O (without hitting the disk though) so it
  33     // should not be called on the critical path.
  34     return base::android::SysUtils::AmountOfPhysicalMemoryKB() * 1024 / 8;
  35   }
  36 };
  37
  38 LazyInstance<DiscardableMemoryAllocatorWrapper>::Leaky g_context =
  39     LAZY_INSTANCE_INITIALIZER;
  40
  41 }  // namespace
  42
  43 // static
  44 void DiscardableMemory::RegisterMemoryPressureListeners() {
  45   internal::DiscardableMemoryEmulated::RegisterMemoryPressureListeners();
  46 }
  47
  48 // static
  49 void DiscardableMemory::UnregisterMemoryPressureListeners() {
  50   internal::DiscardableMemoryEmulated::UnregisterMemoryPressureListeners();
  51 }
  52
  53 // static
  54 void DiscardableMemory::GetSupportedTypes(
  55     std::vector<DiscardableMemoryType>* types) {
  56   const DiscardableMemoryType supported_types[] = {
  57     DISCARDABLE_MEMORY_TYPE_ANDROID,
  58     DISCARDABLE_MEMORY_TYPE_EMULATED,
  59     DISCARDABLE_MEMORY_TYPE_MALLOC
  60   };
  61   types->assign(supported_types, supported_types + arraysize(supported_types));
  62 }
  63
  64 // static
  65 scoped_ptr<DiscardableMemory> DiscardableMemory::CreateLockedMemoryWithType(
  66     DiscardableMemoryType type, size_t size) {
  67   switch (type) {
  68     case DISCARDABLE_MEMORY_TYPE_NONE:
  69     case DISCARDABLE_MEMORY_TYPE_MAC:
  70       return scoped_ptr<DiscardableMemory>();
  71     case DISCARDABLE_MEMORY_TYPE_ANDROID: {
  72       return g_context.Pointer()->allocator.Allocate(size);
  73     }
  74     case DISCARDABLE_MEMORY_TYPE_EMULATED: {
  75       scoped_ptr<internal::DiscardableMemoryEmulated> memory(
  76           new internal::DiscardableMemoryEmulated(size));
  77       if (!memory->Initialize())
  78         return scoped_ptr<DiscardableMemory>();
  79
  80       return memory.PassAs<DiscardableMemory>();
  81     }
  82     case DISCARDABLE_MEMORY_TYPE_MALLOC: {
  83       scoped_ptr<internal::DiscardableMemoryMalloc> memory(
  84           new internal::DiscardableMemoryMalloc(size));
  85       if (!memory->Initialize())
  86         return scoped_ptr<DiscardableMemory>();
  87
  88       return memory.PassAs<DiscardableMemory>();
  89     }
  90   }
  91
  92   NOTREACHED();
  93   return scoped_ptr<DiscardableMemory>();
  94 }
  95
  96 // static
  97 bool DiscardableMemory::PurgeForTestingSupported() {
  98   return false;
  99 }
 100
 101 // static
 102 void DiscardableMemory::PurgeForTesting() {
 103   NOTIMPLEMENTED();
 104 }
 105
 106 }  // namespace base