NotForReview: Expose the global memory budget (chromium side)

content/child/memory/child_memory_coordinator_impl.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/child/memory/child_memory_coordinator_impl.h"
 
 #include "base/lazy_instance.h"
 #include "base/memory/memory_coordinator_client_registry.h"
 #include "base/memory/ptr_util.h"
 #include "base/synchronization/lock.h"
@@ skipping 32 matching lines @@
 
 ChildMemoryCoordinatorImpl::ChildMemoryCoordinatorImpl(
     mojom::MemoryCoordinatorHandlePtr parent,
     ChildMemoryCoordinatorDelegate* delegate)
     : binding_(this), parent_(std::move(parent)), delegate_(delegate) {
   base::AutoLock lock(*g_lock.Pointer());
   DCHECK(delegate_);
   DCHECK(!g_child_memory_coordinator);
   g_child_memory_coordinator = this;
   parent_->AddChild(binding_.CreateInterfacePtrAndBind());
+  parent_->GetGlobalBudgetHandle(
+      base::Bind(&ChildMemoryCoordinatorImpl::OnGetGlobalBudgetHandle,
+                 base::Unretained(this)));
   base::MemoryCoordinatorProxy::SetMemoryCoordinator(this);
 }
 
 ChildMemoryCoordinatorImpl::~ChildMemoryCoordinatorImpl() {
   base::AutoLock lock(*g_lock.Pointer());
   DCHECK(g_child_memory_coordinator == this);
   g_child_memory_coordinator = nullptr;
 }
 
 base::MemoryState ChildMemoryCoordinatorImpl::GetCurrentMemoryState() const {
   return current_state_;
 }
 
+int64_t ChildMemoryCoordinatorImpl::GetGlobalBudget() {
+  if (!global_budget_handle_.is_valid())
+    return -1;
+  return *reinterpret_cast<int64_t*>(global_budget_mapping_.get());
+}
+
+void ChildMemoryCoordinatorImpl::SetGlobalBudgetUpdateInterval(
+    uint32_t interval_ms) {
+  parent_->SetGlobalBudgetUpdateInterval(interval_ms);
+}
+
 void ChildMemoryCoordinatorImpl::PurgeMemory() {
   TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("memory-infra"),
                "ChildMemoryCoordinatorImpl::PurgeMemory");
   base::MemoryCoordinatorClientRegistry::GetInstance()->PurgeMemory();
 }
 
 void ChildMemoryCoordinatorImpl::OnStateChange(mojom::MemoryState state) {
   current_state_ = ToBaseMemoryState(state);
   TRACE_EVENT1(TRACE_DISABLED_BY_DEFAULT("memory-infra"),
                "ChildMemoryCoordinatorImpl::OnStateChange", "state",
                MemoryStateToString(current_state_));
   base::MemoryCoordinatorClientRegistry::GetInstance()->Notify(current_state_);
 }
 
+void ChildMemoryCoordinatorImpl::OnGetGlobalBudgetHandle(
+    mojo::ScopedSharedBufferHandle handle) {
+  global_budget_handle_ = std::move(handle);
+  global_budget_mapping_ = global_budget_handle_->Map(sizeof(int64_t));
+  DCHECK(global_budget_mapping_.get());
+}
+
 #if !defined(OS_ANDROID)
 std::unique_ptr<ChildMemoryCoordinatorImpl> CreateChildMemoryCoordinator(
     mojom::MemoryCoordinatorHandlePtr parent,
     ChildMemoryCoordinatorDelegate* delegate) {
   return base::WrapUnique(
       new ChildMemoryCoordinatorImpl(std::move(parent), delegate));
 }
 #endif
 
 }  // namespace content