OLD | NEW |
1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. | 1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. |
2 // Use of this source code is governed by a BSD-style license that can be | 2 // Use of this source code is governed by a BSD-style license that can be |
3 // found in the LICENSE file. | 3 // found in the LICENSE file. |
4 | 4 |
5 #include "content/common/gamepad_seqlock.h" | 5 #include "content/common/gamepad_seqlock.h" |
6 | 6 |
7 #include <stdlib.h> | 7 #include <stdlib.h> |
8 | 8 |
9 #include "base/atomic_ref_count.h" | 9 #include "base/atomic_ref_count.h" |
10 #include "base/threading/platform_thread.h" | 10 #include "base/threading/platform_thread.h" |
(...skipping 18 matching lines...) Expand all Loading... |
29 base::subtle::Atomic32* ready) { | 29 base::subtle::Atomic32* ready) { |
30 seqlock_ = seqlock; | 30 seqlock_ = seqlock; |
31 data_ = data; | 31 data_ = data; |
32 ready_ = ready; | 32 ready_ = ready; |
33 } | 33 } |
34 virtual void ThreadMain() { | 34 virtual void ThreadMain() { |
35 while (AtomicRefCountIsZero(ready_)) { | 35 while (AtomicRefCountIsZero(ready_)) { |
36 PlatformThread::YieldCurrentThread(); | 36 PlatformThread::YieldCurrentThread(); |
37 } | 37 } |
38 | 38 |
39 for (unsigned i = 0; i < 10000; ++i) { | 39 for (unsigned i = 0; i < 1000; ++i) { |
40 TestData copy; | 40 TestData copy; |
41 base::subtle::Atomic32 version; | 41 base::subtle::Atomic32 version; |
42 do { | 42 do { |
43 version = seqlock_->ReadBegin(); | 43 version = seqlock_->ReadBegin(); |
44 copy = *data_; | 44 copy = *data_; |
45 } while (seqlock_->ReadRetry(version)); | 45 } while (seqlock_->ReadRetry(version)); |
46 | 46 |
47 EXPECT_EQ(copy.a + 100, copy.b); | 47 EXPECT_EQ(copy.a + 100, copy.b); |
48 EXPECT_EQ(copy.c, copy.b + copy.a); | 48 EXPECT_EQ(copy.c, copy.b + copy.a); |
49 } | 49 } |
50 | 50 |
51 AtomicRefCountDec(ready_); | 51 AtomicRefCountDec(ready_); |
52 } | 52 } |
53 | 53 |
54 private: | 54 private: |
55 content::GamepadSeqLock* seqlock_; | 55 content::GamepadSeqLock* seqlock_; |
56 TestData* data_; | 56 TestData* data_; |
57 base::AtomicRefCount* ready_; | 57 base::AtomicRefCount* ready_; |
58 | 58 |
59 DISALLOW_COPY_AND_ASSIGN(BasicSeqLockTestThread); | 59 DISALLOW_COPY_AND_ASSIGN(BasicSeqLockTestThread); |
60 }; | 60 }; |
61 | 61 |
62 TEST(GamepadSeqLockTest, ManyThreads) { | 62 TEST(GamepadSeqLockTest, ManyThreads) { |
63 content::GamepadSeqLock seqlock; | 63 content::GamepadSeqLock seqlock; |
64 TestData data = { 0, 0, 0 }; | 64 TestData data = { 0, 0, 0 }; |
65 base::AtomicRefCount ready = 0; | 65 base::AtomicRefCount ready = 0; |
66 | 66 |
67 ANNOTATE_BENIGN_RACE_SIZED(&data, sizeof(data), "Racey reads are discarded"); | 67 ANNOTATE_BENIGN_RACE_SIZED(&data, sizeof(data), "Racey reads are discarded"); |
68 | 68 |
69 static const unsigned kNumReaderThreads = 100; | 69 static const unsigned kNumReaderThreads = 10; |
70 BasicSeqLockTestThread threads[kNumReaderThreads]; | 70 BasicSeqLockTestThread threads[kNumReaderThreads]; |
71 PlatformThreadHandle handles[kNumReaderThreads]; | 71 PlatformThreadHandle handles[kNumReaderThreads]; |
72 | 72 |
73 for (unsigned i = 0; i < kNumReaderThreads; ++i) | 73 for (unsigned i = 0; i < kNumReaderThreads; ++i) |
74 threads[i].Init(&seqlock, &data, &ready); | 74 threads[i].Init(&seqlock, &data, &ready); |
75 for (unsigned i = 0; i < kNumReaderThreads; ++i) | 75 for (unsigned i = 0; i < kNumReaderThreads; ++i) |
76 ASSERT_TRUE(PlatformThread::Create(0, &threads[i], &handles[i])); | 76 ASSERT_TRUE(PlatformThread::Create(0, &threads[i], &handles[i])); |
77 | 77 |
78 // The main thread is the writer, and the spawned are readers. | 78 // The main thread is the writer, and the spawned are readers. |
79 unsigned counter = 0; | 79 unsigned counter = 0; |
80 for (;;) { | 80 for (;;) { |
81 seqlock.WriteBegin(); | 81 seqlock.WriteBegin(); |
82 data.a = counter++; | 82 data.a = counter++; |
83 data.b = data.a + 100; | 83 data.b = data.a + 100; |
84 data.c = data.b + data.a; | 84 data.c = data.b + data.a; |
85 seqlock.WriteEnd(); | 85 seqlock.WriteEnd(); |
86 | 86 |
87 if (counter == 1) | 87 if (counter == 1) |
88 base::AtomicRefCountIncN(&ready, kNumReaderThreads); | 88 base::AtomicRefCountIncN(&ready, kNumReaderThreads); |
89 | 89 |
90 if (AtomicRefCountIsZero(&ready)) | 90 if (AtomicRefCountIsZero(&ready)) |
91 break; | 91 break; |
92 } | 92 } |
93 | 93 |
94 for (unsigned i = 0; i < kNumReaderThreads; ++i) | 94 for (unsigned i = 0; i < kNumReaderThreads; ++i) |
95 PlatformThread::Join(handles[i]); | 95 PlatformThread::Join(handles[i]); |
96 } | 96 } |
97 | 97 |
98 } // namespace base | 98 } // namespace base |
OLD | NEW |