Architecture for cross-process memory notification suppressing

content/browser/memory/memory_pressure_controller_browsertest.cc

+// Copyright 2015 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 "base/bind.h"
+#include "base/memory/memory_pressure_listener.h"
+#include "content/browser/memory/memory_message_filter.h"
+#include "content/browser/memory/memory_pressure_controller.h"
+#include "content/common/memory_messages.h"
+#include "content/public/test/content_browser_test.h"
+#include "content/public/test/content_browser_test_utils.h"
+#include "content/public/test/test_utils.h"
+#include "ipc/ipc_message.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+namespace content {
+namespace {
+
+MATCHER_P(IsSetSuppressedMessage, suppressed, "") {
+  if (arg == nullptr)
+    return false;
+  MemoryMsg_SetPressureNotificationsSuppressed::Param param;
+  if (!MemoryMsg_SetPressureNotificationsSuppressed::Read(arg, &param))
+    return false;
+  return suppressed == base::get<0>(param);
+}
+
+class MemoryMessageFilterForTesting : public MemoryMessageFilter {
+ public:
+  MOCK_METHOD1(Send, bool(IPC::Message* message));
+
+  void Add() {
+    // The filter must be added on the IO thread.
+    if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
+      BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+                              base::Bind(&MemoryMessageFilterForTesting::Add,
+                                         base::Unretained(this)));
+      RunAllPendingInMessageLoop(BrowserThread::IO);
+      return;
+    }
+    OnChannelConnected(0);
+    OnFilterAdded(nullptr);
+  }
+
+  void Remove() {
+    // The filter must be removed on the IO thread.
+    if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
+      BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+                              base::Bind(&MemoryMessageFilterForTesting::Remove,
+                                         base::Unretained(this)));
+      RunAllPendingInMessageLoop(BrowserThread::IO);
+      return;
+    }
+    OnChannelClosing();
+    OnFilterRemoved();
+  }
+
+ protected:
+  ~MemoryMessageFilterForTesting() override {}
+};
+
+class MemoryPressureControllerBrowserTest : public ContentBrowserTest {
+ protected:
+  void SetPressureNotificationsSuppressedInAllProcessesAndWait(
+      bool suppressed) {
+    MemoryPressureController::GetInstance()
+        ->SetPressureNotificationsSuppressedInAllProcesses(suppressed);
+    RunAllPendingInMessageLoop(BrowserThread::IO);
+  }
+};
+
+IN_PROC_BROWSER_TEST_F(MemoryPressureControllerBrowserTest,
+                       SetPressureNotificationsSuppressedInAllProcesses) {
+  scoped_refptr<MemoryMessageFilterForTesting> filter1(
+      new MemoryMessageFilterForTesting);
+  scoped_refptr<MemoryMessageFilterForTesting> filter2(
+      new MemoryMessageFilterForTesting);
+
+  NavigateToURL(shell(), GetTestUrl("", "title.html"));
+
+  // Add the first filter. No messages should be sent because notifications are
+  // not suppressed.
+  EXPECT_CALL(*filter1, Send(testing::_)).Times(0);
+  EXPECT_CALL(*filter2, Send(testing::_)).Times(0);
+  filter1->Add();
+  EXPECT_FALSE(base::MemoryPressureListener::AreNotificationsSuppressed());
+
+  // Enable suppressing memory pressure notifications in all processes. The
+  // first filter should send a message.
+  EXPECT_CALL(*filter1, Send(IsSetSuppressedMessage(true))).Times(1);
+  EXPECT_CALL(*filter2, Send(testing::_)).Times(0);
+  SetPressureNotificationsSuppressedInAllProcessesAndWait(true);
+  EXPECT_TRUE(base::MemoryPressureListener::AreNotificationsSuppressed());
+
+  // Add the second filter. It should send a message because notifications are
+  // suppressed.
+  EXPECT_CALL(*filter1, Send(testing::_)).Times(0);
+  EXPECT_CALL(*filter2, Send(IsSetSuppressedMessage(true))).Times(1);
+  filter2->Add();
+
+  // Disable suppressing memory pressure notifications in all processes. Both
+  // filters should send a message.
+  EXPECT_CALL(*filter1, Send(IsSetSuppressedMessage(false))).Times(1);
+  EXPECT_CALL(*filter2, Send(IsSetSuppressedMessage(false))).Times(1);
+  SetPressureNotificationsSuppressedInAllProcessesAndWait(false);
+  EXPECT_FALSE(base::MemoryPressureListener::AreNotificationsSuppressed());
+
+  // Remove the first filter. No messages should be sent.
+  EXPECT_CALL(*filter1, Send(testing::_)).Times(0);
+  EXPECT_CALL(*filter2, Send(testing::_)).Times(0);
+  filter1->Remove();
+
+  // Enable suppressing memory pressure notifications in all processes. The
+  // second filter should send a message.
+  EXPECT_CALL(*filter1, Send(testing::_)).Times(0);
+  EXPECT_CALL(*filter2, Send(IsSetSuppressedMessage(true))).Times(1);
+  SetPressureNotificationsSuppressedInAllProcessesAndWait(true);
+  EXPECT_TRUE(base::MemoryPressureListener::AreNotificationsSuppressed());
+
+  // Remove the second filter and disable suppressing memory pressure
+  // notifications in all processes. No messages should be sent.
+  EXPECT_CALL(*filter1, Send(testing::_)).Times(0);
+  EXPECT_CALL(*filter2, Send(testing::_)).Times(0);
+  filter2->Remove();
+  SetPressureNotificationsSuppressedInAllProcessesAndWait(false);
+  EXPECT_FALSE(base::MemoryPressureListener::AreNotificationsSuppressed());
+}
+
+}  // namespace
+}  // namespace content