Add unit-test for SharedSampler handling of zero-thread processes.

chrome/browser/task_manager/sampling/shared_sampler_unittest_win.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 "chrome/browser/task_manager/sampling/shared_sampler.h"
-
-#include <windows.h>
-
-#include <memory>
-
-#include "base/callback.h"
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/run_loop.h"
-#include "base/sequenced_task_runner.h"
-#include "base/time/time.h"
-#include "chrome/browser/task_manager/task_manager_observer.h"
-#include "content/public/browser/browser_thread.h"
-#include "content/public/test/test_browser_thread_bundle.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace task_manager {
-
-// This test class drives SharedSampler in a way similar to the real
-// implementation in TaskManagerImpl and TaskGroup.
-class SharedSamplerTest : public testing::Test {
- public:
-  SharedSamplerTest()
-    : blocking_pool_runner_(GetBlockingPoolRunner()),
-      shared_sampler_(new SharedSampler(blocking_pool_runner_)) {
-    shared_sampler_->RegisterCallbacks(
-        base::GetCurrentProcId(),
-        base::Bind(&SharedSamplerTest::OnIdleWakeupsRefreshDone,
-                   base::Unretained(this)),
-        base::Bind(&SharedSamplerTest::OnPhysicalMemoryUsageRefreshDone,
-                   base::Unretained(this)),
-        base::Bind(&SharedSamplerTest::OnStartTimeRefreshDone,
-                   base::Unretained(this)),
-        base::Bind(&SharedSamplerTest::OnCpuTimeRefreshDone,
-                   base::Unretained(this)));
-   }
-
-  ~SharedSamplerTest() override {}
-
- protected:
-  int64_t physical_bytes() const { return physical_bytes_; }
-
-  base::Time start_time() const { return start_time_; }
-
-  base::TimeDelta cpu_time() const { return cpu_time_; }
-
-  int idle_wakeups_per_second() const { return idle_wakeups_per_second_; }
-
-  int64_t finished_refresh_type() const { return finished_refresh_type_; }
-
-  void StartRefresh(int64_t refresh_flags) {
-    finished_refresh_type_ = 0;
-    expected_refresh_type_ = refresh_flags;
-    shared_sampler_->Refresh(base::GetCurrentProcId(), refresh_flags);
-  }
-
-  void WaitUntilRefreshDone() {
-    base::RunLoop run_loop;
-    quit_closure_ = run_loop.QuitWhenIdleClosure();
-    run_loop.Run();
-  }
-
- private:
-  static scoped_refptr<base::SequencedTaskRunner> GetBlockingPoolRunner() {
-    base::SequencedWorkerPool* blocking_pool =
-        content::BrowserThread::GetBlockingPool();
-    return blocking_pool->GetSequencedTaskRunner(
-        blocking_pool->GetSequenceToken());
-  }
-
-  void OnRefreshTypeFinished(int64_t finished_refresh_type) {
-    finished_refresh_type_ |= finished_refresh_type;
-
-    if (finished_refresh_type_ == expected_refresh_type_)
-      quit_closure_.Run();
-  }
-
-  void OnPhysicalMemoryUsageRefreshDone(int64_t physical_bytes) {
-    physical_bytes_ = physical_bytes;
-    OnRefreshTypeFinished(REFRESH_TYPE_PHYSICAL_MEMORY);
-  }
-
-  void OnIdleWakeupsRefreshDone(int idle_wakeups_per_second) {
-    idle_wakeups_per_second_ = idle_wakeups_per_second;
-    OnRefreshTypeFinished(REFRESH_TYPE_IDLE_WAKEUPS);
-  }
-
-  void OnStartTimeRefreshDone(base::Time start_time) {
-    start_time_ = start_time;
-    OnRefreshTypeFinished(REFRESH_TYPE_START_TIME);
-  }
-
-  void OnCpuTimeRefreshDone(base::TimeDelta cpu_time) {
-    cpu_time_ = cpu_time;
-    OnRefreshTypeFinished(REFRESH_TYPE_CPU_TIME);
-  }
-
-  int64_t expected_refresh_type_ = 0;
-  int64_t finished_refresh_type_ = 0;
-  base::Closure quit_closure_;
-
-  int64_t physical_bytes_ = 0;
-  int idle_wakeups_per_second_ = -1;
-  base::Time start_time_;
-  base::TimeDelta cpu_time_;
-
-  content::TestBrowserThreadBundle thread_bundle_;
-  scoped_refptr<base::SequencedTaskRunner> blocking_pool_runner_;
-  scoped_refptr<SharedSampler> shared_sampler_;
-
-  DISALLOW_COPY_AND_ASSIGN(SharedSamplerTest);
-};
-
-// Tests that Idle Wakeups per second value can be obtained from SharedSampler.
-TEST_F(SharedSamplerTest, IdleWakeups) {
-  StartRefresh(REFRESH_TYPE_IDLE_WAKEUPS);
-  WaitUntilRefreshDone();
-  EXPECT_EQ(REFRESH_TYPE_IDLE_WAKEUPS, finished_refresh_type());
-
-  // Since idle_wakeups_per_second is an incremental value that reflects delta
-  // between two refreshes, the first refresh always returns zero value. This
-  // is consistent with implementation on other platforms.
-  EXPECT_EQ(0, idle_wakeups_per_second());
-
-  // Do a short sleep - that should trigger a context switch.
-  ::Sleep(1);
-
-  // Do another refresh.
-  StartRefresh(REFRESH_TYPE_IDLE_WAKEUPS);
-  WaitUntilRefreshDone();
-
-  // Should get a greater than zero rate now.
-  EXPECT_GT(idle_wakeups_per_second(), 0);
-}
-
-// Verifies that Memory (Private WS) value can be obtained from Shared Sampler.
-TEST_F(SharedSamplerTest, PhysicalMemory) {
-  StartRefresh(REFRESH_TYPE_PHYSICAL_MEMORY);
-  WaitUntilRefreshDone();
-  EXPECT_EQ(REFRESH_TYPE_PHYSICAL_MEMORY, finished_refresh_type());
-
-  int64_t initial_value = physical_bytes();
-
-  // Allocate a large continuos block of memory.
-  const int allocated_size = 4 * 1024 * 1024;
-  std::vector<uint8_t> memory_block(allocated_size);
-
-  StartRefresh(REFRESH_TYPE_PHYSICAL_MEMORY);
-  WaitUntilRefreshDone();
-
-  // Verify that physical bytes has increased accordingly.
-  EXPECT_GE(physical_bytes(), initial_value + allocated_size);
-}
-
-// Tests that process start time can be obtained from SharedSampler.
-TEST_F(SharedSamplerTest, StartTime) {
-  StartRefresh(REFRESH_TYPE_START_TIME);
-  WaitUntilRefreshDone();
-  EXPECT_EQ(REFRESH_TYPE_START_TIME, finished_refresh_type());
-
-  // Should get a greater than zero now.
-  base::Time start_time_prev = start_time();
-  EXPECT_GT(start_time_prev, base::Time());
-
-  // Do a refresh.
-  StartRefresh(REFRESH_TYPE_START_TIME);
-  WaitUntilRefreshDone();
-
-  // Start time should not change.
-  EXPECT_EQ(start_time(), start_time_prev);
-}
-
-// Tests that CPU time can be obtained from SharedSampler.
-TEST_F(SharedSamplerTest, CpuTime) {
-  StartRefresh(REFRESH_TYPE_CPU_TIME);
-  WaitUntilRefreshDone();
-  EXPECT_EQ(REFRESH_TYPE_CPU_TIME, finished_refresh_type());
-
-  base::TimeDelta cpu_time_prev = cpu_time();
-
-  // Do a refresh.
-  StartRefresh(REFRESH_TYPE_CPU_TIME);
-  WaitUntilRefreshDone();
-
-  // CPU time should not decrease.
-  EXPECT_GE(cpu_time(), cpu_time_prev);
-}
-
-// Verifies that multiple refresh types can be refreshed at the same time.
-TEST_F(SharedSamplerTest, MultipleRefreshTypes) {
-  StartRefresh(REFRESH_TYPE_IDLE_WAKEUPS | REFRESH_TYPE_PHYSICAL_MEMORY |
-               REFRESH_TYPE_START_TIME | REFRESH_TYPE_CPU_TIME);
-  WaitUntilRefreshDone();
-  EXPECT_EQ(REFRESH_TYPE_IDLE_WAKEUPS | REFRESH_TYPE_PHYSICAL_MEMORY |
-                REFRESH_TYPE_START_TIME | REFRESH_TYPE_CPU_TIME,
-            finished_refresh_type());
-}
-
-}  // namespace task_manager