1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
/*
* Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef RTC_BASE_RACE_CHECKER_H_
#define RTC_BASE_RACE_CHECKER_H_
#include "rtc_base/checks.h"
#include "rtc_base/platform_thread_types.h"
#include "rtc_base/thread_annotations.h"
namespace rtc {
namespace internal {
class RaceCheckerScope;
} // namespace internal
// Best-effort race-checking implementation. This primitive uses no
// synchronization at all to be as-fast-as-possible in the non-racy case.
class RTC_LOCKABLE RaceChecker {
public:
friend class internal::RaceCheckerScope;
RaceChecker();
private:
bool Acquire() const RTC_EXCLUSIVE_LOCK_FUNCTION();
void Release() const RTC_UNLOCK_FUNCTION();
// Volatile to prevent code being optimized away in Acquire()/Release().
mutable volatile int access_count_ = 0;
mutable volatile PlatformThreadRef accessing_thread_;
};
namespace internal {
class RTC_SCOPED_LOCKABLE RaceCheckerScope {
public:
explicit RaceCheckerScope(const RaceChecker* race_checker)
RTC_EXCLUSIVE_LOCK_FUNCTION(race_checker);
bool RaceDetected() const;
~RaceCheckerScope() RTC_UNLOCK_FUNCTION();
private:
const RaceChecker* const race_checker_;
const bool race_check_ok_;
};
class RTC_SCOPED_LOCKABLE RaceCheckerScopeDoNothing {
public:
explicit RaceCheckerScopeDoNothing(const RaceChecker* race_checker)
RTC_EXCLUSIVE_LOCK_FUNCTION(race_checker) {}
~RaceCheckerScopeDoNothing() RTC_UNLOCK_FUNCTION() {}
};
} // namespace internal
} // namespace rtc
#define RTC_CHECK_RUNS_SERIALIZED(x) \
rtc::internal::RaceCheckerScope race_checker(x); \
RTC_CHECK(!race_checker.RaceDetected())
#if RTC_DCHECK_IS_ON
#define RTC_DCHECK_RUNS_SERIALIZED(x) \
rtc::internal::RaceCheckerScope race_checker(x); \
RTC_DCHECK(!race_checker.RaceDetected())
#else
#define RTC_DCHECK_RUNS_SERIALIZED(x) \
rtc::internal::RaceCheckerScopeDoNothing race_checker(x)
#endif
#endif // RTC_BASE_RACE_CHECKER_H_
|
