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Issue 13265003: cc: Switch ContentLayerUpdater to use RenderingStatsInstrumentation (Closed) Base URL: http://git.chromium.org/chromium/src.git@update
Patch Set: Added printfs Created 7 years, 8 months ago
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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 #ifndef BASE_SYNCHRONIZATION_LOCK_H_ 5 #ifndef BASE_SYNCHRONIZATION_LOCK_H_
6 #define BASE_SYNCHRONIZATION_LOCK_H_ 6 #define BASE_SYNCHRONIZATION_LOCK_H_
7 7
8 #include "base/base_export.h" 8 #include "base/base_export.h"
9 #include "base/synchronization/lock_impl.h" 9 #include "base/synchronization/lock_impl.h"
10 #include "base/threading/platform_thread.h" 10 #include "base/threading/platform_thread.h"
11 11
12 namespace base { 12 namespace base {
13 13
14 // A convenient wrapper for an OS specific critical section. The only real 14 // A convenient wrapper for an OS specific critical section. The only real
15 // intelligence in this class is in debug mode for the support for the 15 // intelligence in this class is in debug mode for the support for the
16 // AssertAcquired() method. 16 // AssertAcquired() method.
17 class BASE_EXPORT Lock { 17 class BASE_EXPORT Lock {
18 public: 18 public:
19 #if defined(NDEBUG) // Optimized wrapper implementation
20 Lock() : lock_() {}
21 ~Lock() {}
22 void Acquire() { lock_.Lock(); }
23 void Release() { lock_.Unlock(); }
24
25 // If the lock is not held, take it and return true. If the lock is already
26 // held by another thread, immediately return false. This must not be called
27 // by a thread already holding the lock (what happens is undefined and an
28 // assertion may fail).
29 bool Try() { return lock_.Try(); }
30
31 // Null implementation if not debug.
32 void AssertAcquired() const {}
33 #else
34 Lock(); 19 Lock();
35 ~Lock() {} 20 ~Lock() {}
36 21
37 // NOTE: Although windows critical sections support recursive locks, we do not 22 // NOTE: Although windows critical sections support recursive locks, we do not
38 // allow this, and we will commonly fire a DCHECK() if a thread attempts to 23 // allow this, and we will commonly fire a DCHECK() if a thread attempts to
39 // acquire the lock a second time (while already holding it). 24 // acquire the lock a second time (while already holding it).
40 void Acquire() { 25 void Acquire() {
41 lock_.Lock(); 26 lock_.Lock();
42 CheckUnheldAndMark(); 27 CheckUnheldAndMark();
43 } 28 }
44 void Release() { 29 void Release() {
45 CheckHeldAndUnmark(); 30 CheckHeldAndUnmark();
46 lock_.Unlock(); 31 lock_.Unlock();
47 } 32 }
48 33
49 bool Try() { 34 bool Try() {
50 bool rv = lock_.Try(); 35 bool rv = lock_.Try();
51 if (rv) { 36 if (rv) {
52 CheckUnheldAndMark(); 37 CheckUnheldAndMark();
53 } 38 }
54 return rv; 39 return rv;
55 } 40 }
56 41
57 void AssertAcquired() const; 42 void AssertAcquired() const;
58 #endif // NDEBUG
59 43
60 #if defined(OS_POSIX) 44 #if defined(OS_POSIX)
61 // The posix implementation of ConditionVariable needs to be able 45 // The posix implementation of ConditionVariable needs to be able
62 // to see our lock and tweak our debugging counters, as it releases 46 // to see our lock and tweak our debugging counters, as it releases
63 // and acquires locks inside of pthread_cond_{timed,}wait. 47 // and acquires locks inside of pthread_cond_{timed,}wait.
64 friend class ConditionVariable; 48 friend class ConditionVariable;
65 #elif defined(OS_WIN) 49 #elif defined(OS_WIN)
66 // The Windows Vista implementation of ConditionVariable needs the 50 // The Windows Vista implementation of ConditionVariable needs the
67 // native handle of the critical section. 51 // native handle of the critical section.
68 friend class WinVistaCondVar; 52 friend class WinVistaCondVar;
69 #endif 53 #endif
70 54
71 private: 55 private:
72 #if !defined(NDEBUG)
73 // Members and routines taking care of locks assertions. 56 // Members and routines taking care of locks assertions.
74 // Note that this checks for recursive locks and allows them 57 // Note that this checks for recursive locks and allows them
75 // if the variable is set. This is allowed by the underlying implementation 58 // if the variable is set. This is allowed by the underlying implementation
76 // on windows but not on Posix, so we're doing unneeded checks on Posix. 59 // on windows but not on Posix, so we're doing unneeded checks on Posix.
77 // It's worth it to share the code. 60 // It's worth it to share the code.
78 void CheckHeldAndUnmark(); 61 void CheckHeldAndUnmark();
79 void CheckUnheldAndMark(); 62 void CheckUnheldAndMark();
80 63
81 // All private data is implicitly protected by lock_. 64 // All private data is implicitly protected by lock_.
82 // Be VERY careful to only access members under that lock. 65 // Be VERY careful to only access members under that lock.
83 66
84 // Determines validity of owning_thread_id_. Needed as we don't have 67 // Determines validity of owning_thread_id_. Needed as we don't have
85 // a null owning_thread_id_ value. 68 // a null owning_thread_id_ value.
86 bool owned_by_thread_; 69 bool owned_by_thread_;
87 base::PlatformThreadId owning_thread_id_; 70 base::PlatformThreadId owning_thread_id_;
88 #endif // NDEBUG
89 71
90 // Platform specific underlying lock implementation. 72 // Platform specific underlying lock implementation.
91 internal::LockImpl lock_; 73 internal::LockImpl lock_;
92 74
93 DISALLOW_COPY_AND_ASSIGN(Lock); 75 DISALLOW_COPY_AND_ASSIGN(Lock);
94 }; 76 };
95 77
96 // A helper class that acquires the given Lock while the AutoLock is in scope. 78 // A helper class that acquires the given Lock while the AutoLock is in scope.
97 class AutoLock { 79 class AutoLock {
98 public: 80 public:
(...skipping 26 matching lines...) Expand all
125 } 107 }
126 108
127 private: 109 private:
128 Lock& lock_; 110 Lock& lock_;
129 DISALLOW_COPY_AND_ASSIGN(AutoUnlock); 111 DISALLOW_COPY_AND_ASSIGN(AutoUnlock);
130 }; 112 };
131 113
132 } // namespace base 114 } // namespace base
133 115
134 #endif // BASE_SYNCHRONIZATION_LOCK_H_ 116 #endif // BASE_SYNCHRONIZATION_LOCK_H_
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