Reland of [tracing] Display the locked size of discardable memory segment.

base/memory/discardable_shared_memory_unittest.cc

 // Copyright 2014 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/basictypes.h"
 #include "base/memory/discardable_shared_memory.h"
 #include "base/process/process_metrics.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
@@ skipping 15 matching lines @@
   Time now_;
 };
 
 TEST(DiscardableSharedMemoryTest, CreateAndMap) {
   const uint32 kDataSize = 1024;
 
   TestDiscardableSharedMemory memory;
   bool rv = memory.CreateAndMap(kDataSize);
   ASSERT_TRUE(rv);
   EXPECT_GE(memory.mapped_size(), kDataSize);
+  EXPECT_TRUE(memory.IsMemoryLocked());
 }
 
 TEST(DiscardableSharedMemoryTest, CreateFromHandle) {
   const uint32 kDataSize = 1024;
 
   TestDiscardableSharedMemory memory1;
   bool rv = memory1.CreateAndMap(kDataSize);
   ASSERT_TRUE(rv);
 
   SharedMemoryHandle shared_handle;
   ASSERT_TRUE(
       memory1.ShareToProcess(GetCurrentProcessHandle(), &shared_handle));
   ASSERT_TRUE(SharedMemory::IsHandleValid(shared_handle));
 
   TestDiscardableSharedMemory memory2(shared_handle);
   rv = memory2.Map(kDataSize);
   ASSERT_TRUE(rv);
+  EXPECT_TRUE(memory2.IsMemoryLocked());
 }
 
 TEST(DiscardableSharedMemoryTest, LockAndUnlock) {
   const uint32 kDataSize = 1024;
 
   TestDiscardableSharedMemory memory1;
   bool rv = memory1.CreateAndMap(kDataSize);
   ASSERT_TRUE(rv);
 
   // Memory is initially locked. Unlock it.
   memory1.SetNow(Time::FromDoubleT(1));
   memory1.Unlock(0, 0);
+  EXPECT_FALSE(memory1.IsMemoryLocked());
 
   // Lock and unlock memory.
   auto lock_rv = memory1.Lock(0, 0);
   EXPECT_EQ(DiscardableSharedMemory::SUCCESS, lock_rv);
   memory1.SetNow(Time::FromDoubleT(2));
   memory1.Unlock(0, 0);
 
   // Lock again before duplicating and passing ownership to new instance.
   lock_rv = memory1.Lock(0, 0);
   EXPECT_EQ(DiscardableSharedMemory::SUCCESS, lock_rv);
+  EXPECT_TRUE(memory1.IsMemoryLocked());
 
   SharedMemoryHandle shared_handle;
   ASSERT_TRUE(
       memory1.ShareToProcess(GetCurrentProcessHandle(), &shared_handle));
   ASSERT_TRUE(SharedMemory::IsHandleValid(shared_handle));
 
   TestDiscardableSharedMemory memory2(shared_handle);
   rv = memory2.Map(kDataSize);
   ASSERT_TRUE(rv);
 
   // Unlock second instance.
   memory2.SetNow(Time::FromDoubleT(3));
   memory2.Unlock(0, 0);
 
+  // Both memory instances should be unlocked now.
+  EXPECT_FALSE(memory2.IsMemoryLocked());
+  EXPECT_FALSE(memory1.IsMemoryLocked());
+
   // Lock second instance before passing ownership back to first instance.
   lock_rv = memory2.Lock(0, 0);
   EXPECT_EQ(DiscardableSharedMemory::SUCCESS, lock_rv);
 
-  // Memory should still be resident.
+  // Memory should still be resident and locked.
   rv = memory1.IsMemoryResident();
   EXPECT_TRUE(rv);
+  EXPECT_TRUE(memory1.IsMemoryLocked());
 
   // Unlock first instance.
   memory1.SetNow(Time::FromDoubleT(4));
   memory1.Unlock(0, 0);
 }
 
 TEST(DiscardableSharedMemoryTest, Purge) {
   const uint32 kDataSize = 1024;
 
   TestDiscardableSharedMemory memory1;
@@ skipping 239 matching lines @@
   EXPECT_NE(0u, memory.mapped_size());
 
   // Mapped size should be 0 after shrinking memory segment.
   memory.Shrink();
   EXPECT_EQ(0u, memory.mapped_size());
 }
 #endif
 
 }  // namespace
 }  // namespace base