15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Copyright (c) 2011 The Chromium Authors. All rights reserved. 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Use of this source code is governed by a BSD-style license that can be 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// found in the LICENSE file. 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "content/common/gamepad_seqlock.h" 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <stdlib.h> 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/atomic_ref_count.h" 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/threading/platform_thread.h" 115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/third_party/dynamic_annotations/dynamic_annotations.h" 125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "testing/gtest/include/gtest/gtest.h" 135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace base { 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Basic test to make sure that basic operation works correctly. 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)struct TestData { 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) unsigned a, b, c; 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}; 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)class BasicSeqLockTestThread : public PlatformThread::Delegate { 235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) public: 245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) BasicSeqLockTestThread() {} 255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void Init( 275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) content::GamepadSeqLock* seqlock, 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) TestData* data, 295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) base::subtle::Atomic32* ready) { 305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) seqlock_ = seqlock; 315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) data_ = data; 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) ready_ = ready; 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) virtual void ThreadMain() { 355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) while (AtomicRefCountIsZero(ready_)) { 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) PlatformThread::YieldCurrentThread(); 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) for (unsigned i = 0; i < 1000; ++i) { 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) TestData copy; 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) base::subtle::Atomic32 version; 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) do { 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) version = seqlock_->ReadBegin(); 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) copy = *data_; 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } while (seqlock_->ReadRetry(version)); 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) EXPECT_EQ(copy.a + 100, copy.b); 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) EXPECT_EQ(copy.c, copy.b + copy.a); 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) AtomicRefCountDec(ready_); 525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) private: 555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) content::GamepadSeqLock* seqlock_; 565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) TestData* data_; 575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) base::AtomicRefCount* ready_; 585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DISALLOW_COPY_AND_ASSIGN(BasicSeqLockTestThread); 605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}; 615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)TEST(GamepadSeqLockTest, ManyThreads) { 635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) content::GamepadSeqLock seqlock; 645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) TestData data = { 0, 0, 0 }; 655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) base::AtomicRefCount ready = 0; 665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) ANNOTATE_BENIGN_RACE_SIZED(&data, sizeof(data), "Racey reads are discarded"); 685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) static const unsigned kNumReaderThreads = 10; 705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) BasicSeqLockTestThread threads[kNumReaderThreads]; 715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) PlatformThreadHandle handles[kNumReaderThreads]; 725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) for (unsigned i = 0; i < kNumReaderThreads; ++i) 745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) threads[i].Init(&seqlock, &data, &ready); 755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) for (unsigned i = 0; i < kNumReaderThreads; ++i) 765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) ASSERT_TRUE(PlatformThread::Create(0, &threads[i], &handles[i])); 775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // The main thread is the writer, and the spawned are readers. 795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) unsigned counter = 0; 805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) for (;;) { 815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) seqlock.WriteBegin(); 825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) data.a = counter++; 835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) data.b = data.a + 100; 845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) data.c = data.b + data.a; 855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) seqlock.WriteEnd(); 865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (counter == 1) 885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) base::AtomicRefCountIncN(&ready, kNumReaderThreads); 895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (AtomicRefCountIsZero(&ready)) 915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) break; 925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) for (unsigned i = 0; i < kNumReaderThreads; ++i) 955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) PlatformThread::Join(handles[i]); 965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 975821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 985821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace base 99