Move base to DEPS

base/threading/worker_pool_posix_unittest.cc

-// Copyright (c) 2012 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/threading/worker_pool_posix.h"
-
-#include <set>
-
-#include "base/bind.h"
-#include "base/callback.h"
-#include "base/synchronization/condition_variable.h"
-#include "base/synchronization/lock.h"
-#include "base/threading/platform_thread.h"
-#include "base/synchronization/waitable_event.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace base {
-
-// Peer class to provide passthrough access to PosixDynamicThreadPool internals.
-class PosixDynamicThreadPool::PosixDynamicThreadPoolPeer {
- public:
-  explicit PosixDynamicThreadPoolPeer(PosixDynamicThreadPool* pool)
-      : pool_(pool) {}
-
-  Lock* lock() { return &pool_->lock_; }
-  ConditionVariable* pending_tasks_available_cv() {
-    return &pool_->pending_tasks_available_cv_;
-  }
-  const std::queue<PendingTask>& pending_tasks() const {
-    return pool_->pending_tasks_;
-  }
-  int num_idle_threads() const { return pool_->num_idle_threads_; }
-  ConditionVariable* num_idle_threads_cv() {
-    return pool_->num_idle_threads_cv_.get();
-  }
-  void set_num_idle_threads_cv(ConditionVariable* cv) {
-    pool_->num_idle_threads_cv_.reset(cv);
-  }
-
- private:
-  PosixDynamicThreadPool* pool_;
-
-  DISALLOW_COPY_AND_ASSIGN(PosixDynamicThreadPoolPeer);
-};
-
-namespace {
-
-// IncrementingTask's main purpose is to increment a counter.  It also updates a
-// set of unique thread ids, and signals a ConditionVariable on completion.
-// Note that since it does not block, there is no way to control the number of
-// threads used if more than one IncrementingTask is consecutively posted to the
-// thread pool, since the first one might finish executing before the subsequent
-// PostTask() calls get invoked.
-void IncrementingTask(Lock* counter_lock,
-                      int* counter,
-                      Lock* unique_threads_lock,
-                      std::set<PlatformThreadId>* unique_threads) {
-  {
-    base::AutoLock locked(*unique_threads_lock);
-    unique_threads->insert(PlatformThread::CurrentId());
-  }
-  base::AutoLock locked(*counter_lock);
-  (*counter)++;
-}
-
-// BlockingIncrementingTask is a simple wrapper around IncrementingTask that
-// allows for waiting at the start of Run() for a WaitableEvent to be signalled.
-struct BlockingIncrementingTaskArgs {
-  Lock* counter_lock;
-  int* counter;
-  Lock* unique_threads_lock;
-  std::set<PlatformThreadId>* unique_threads;
-  Lock* num_waiting_to_start_lock;
-  int* num_waiting_to_start;
-  ConditionVariable* num_waiting_to_start_cv;
-  base::WaitableEvent* start;
-};
-
-void BlockingIncrementingTask(const BlockingIncrementingTaskArgs& args) {
-  {
-    base::AutoLock num_waiting_to_start_locked(*args.num_waiting_to_start_lock);
-    (*args.num_waiting_to_start)++;
-  }
-  args.num_waiting_to_start_cv->Signal();
-  args.start->Wait();
-  IncrementingTask(args.counter_lock, args.counter, args.unique_threads_lock,
-                   args.unique_threads);
-}
-
-class PosixDynamicThreadPoolTest : public testing::Test {
- protected:
-  PosixDynamicThreadPoolTest()
-      : pool_(new base::PosixDynamicThreadPool("dynamic_pool", 60*60)),
-        peer_(pool_.get()),
-        counter_(0),
-        num_waiting_to_start_(0),
-        num_waiting_to_start_cv_(&num_waiting_to_start_lock_),
-        start_(true, false) {}
-
-  void SetUp() override {
-    peer_.set_num_idle_threads_cv(new ConditionVariable(peer_.lock()));
-  }
-
-  void TearDown() override {
-    // Wake up the idle threads so they can terminate.
-    if (pool_.get()) pool_->Terminate();
-  }
-
-  void WaitForTasksToStart(int num_tasks) {
-    base::AutoLock num_waiting_to_start_locked(num_waiting_to_start_lock_);
-    while (num_waiting_to_start_ < num_tasks) {
-      num_waiting_to_start_cv_.Wait();
-    }
-  }
-
-  void WaitForIdleThreads(int num_idle_threads) {
-    base::AutoLock pool_locked(*peer_.lock());
-    while (peer_.num_idle_threads() < num_idle_threads) {
-      peer_.num_idle_threads_cv()->Wait();
-    }
-  }
-
-  base::Closure CreateNewIncrementingTaskCallback() {
-    return base::Bind(&IncrementingTask, &counter_lock_, &counter_,
-                      &unique_threads_lock_, &unique_threads_);
-  }
-
-  base::Closure CreateNewBlockingIncrementingTaskCallback() {
-    BlockingIncrementingTaskArgs args = {
-        &counter_lock_, &counter_, &unique_threads_lock_, &unique_threads_,
-        &num_waiting_to_start_lock_, &num_waiting_to_start_,
-        &num_waiting_to_start_cv_, &start_
-    };
-    return base::Bind(&BlockingIncrementingTask, args);
-  }
-
-  scoped_refptr<base::PosixDynamicThreadPool> pool_;
-  base::PosixDynamicThreadPool::PosixDynamicThreadPoolPeer peer_;
-  Lock counter_lock_;
-  int counter_;
-  Lock unique_threads_lock_;
-  std::set<PlatformThreadId> unique_threads_;
-  Lock num_waiting_to_start_lock_;
-  int num_waiting_to_start_;
-  ConditionVariable num_waiting_to_start_cv_;
-  base::WaitableEvent start_;
-};
-
-}  // namespace
-
-TEST_F(PosixDynamicThreadPoolTest, Basic) {
-  EXPECT_EQ(0, peer_.num_idle_threads());
-  EXPECT_EQ(0U, unique_threads_.size());
-  EXPECT_EQ(0U, peer_.pending_tasks().size());
-
-  // Add one task and wait for it to be completed.
-  pool_->PostTask(FROM_HERE, CreateNewIncrementingTaskCallback());
-
-  WaitForIdleThreads(1);
-
-  EXPECT_EQ(1U, unique_threads_.size()) <<
-      "There should be only one thread allocated for one task.";
-  EXPECT_EQ(1, counter_);
-}
-
-TEST_F(PosixDynamicThreadPoolTest, ReuseIdle) {
-  // Add one task and wait for it to be completed.
-  pool_->PostTask(FROM_HERE, CreateNewIncrementingTaskCallback());
-
-  WaitForIdleThreads(1);
-
-  // Add another 2 tasks.  One should reuse the existing worker thread.
-  pool_->PostTask(FROM_HERE, CreateNewBlockingIncrementingTaskCallback());
-  pool_->PostTask(FROM_HERE, CreateNewBlockingIncrementingTaskCallback());
-
-  WaitForTasksToStart(2);
-  start_.Signal();
-  WaitForIdleThreads(2);
-
-  EXPECT_EQ(2U, unique_threads_.size());
-  EXPECT_EQ(2, peer_.num_idle_threads());
-  EXPECT_EQ(3, counter_);
-}
-
-TEST_F(PosixDynamicThreadPoolTest, TwoActiveTasks) {
-  // Add two blocking tasks.
-  pool_->PostTask(FROM_HERE, CreateNewBlockingIncrementingTaskCallback());
-  pool_->PostTask(FROM_HERE, CreateNewBlockingIncrementingTaskCallback());
-
-  EXPECT_EQ(0, counter_) << "Blocking tasks should not have started yet.";
-
-  WaitForTasksToStart(2);
-  start_.Signal();
-  WaitForIdleThreads(2);
-
-  EXPECT_EQ(2U, unique_threads_.size());
-  EXPECT_EQ(2, peer_.num_idle_threads()) << "Existing threads are now idle.";
-  EXPECT_EQ(2, counter_);
-}
-
-TEST_F(PosixDynamicThreadPoolTest, Complex) {
-  // Add two non blocking tasks and wait for them to finish.
-  pool_->PostTask(FROM_HERE, CreateNewIncrementingTaskCallback());
-
-  WaitForIdleThreads(1);
-
-  // Add two blocking tasks, start them simultaneously, and wait for them to
-  // finish.
-  pool_->PostTask(FROM_HERE, CreateNewBlockingIncrementingTaskCallback());
-  pool_->PostTask(FROM_HERE, CreateNewBlockingIncrementingTaskCallback());
-
-  WaitForTasksToStart(2);
-  start_.Signal();
-  WaitForIdleThreads(2);
-
-  EXPECT_EQ(3, counter_);
-  EXPECT_EQ(2, peer_.num_idle_threads());
-  EXPECT_EQ(2U, unique_threads_.size());
-
-  // Wake up all idle threads so they can exit.
-  {
-    base::AutoLock locked(*peer_.lock());
-    while (peer_.num_idle_threads() > 0) {
-      peer_.pending_tasks_available_cv()->Signal();
-      peer_.num_idle_threads_cv()->Wait();
-    }
-  }
-
-  // Add another non blocking task.  There are no threads to reuse.
-  pool_->PostTask(FROM_HERE, CreateNewIncrementingTaskCallback());
-  WaitForIdleThreads(1);
-
-  // The POSIX implementation of PlatformThread::CurrentId() uses pthread_self()
-  // which is not guaranteed to be unique after a thread joins. The OS X
-  // implemntation of pthread_self() returns the address of the pthread_t, which
-  // is merely a malloc()ed pointer stored in the first TLS slot. When a thread
-  // joins and that structure is freed, the block of memory can be put on the
-  // OS free list, meaning the same address could be reused in a subsequent
-  // allocation. This in fact happens when allocating in a loop as this test
-  // does.
-  //
-  // Because there are two concurrent threads, there's at least the guarantee
-  // of having two unique thread IDs in the set. But after those two threads are
-  // joined, the next-created thread can get a re-used ID if the allocation of
-  // the pthread_t structure is taken from the free list. Therefore, there can
-  // be either 2 or 3 unique thread IDs in the set at this stage in the test.
-  EXPECT_TRUE(unique_threads_.size() >= 2 && unique_threads_.size() <= 3)
-      << "unique_threads_.size() = " << unique_threads_.size();
-  EXPECT_EQ(1, peer_.num_idle_threads());
-  EXPECT_EQ(4, counter_);
-}
-
-}  // namespace base