diff options
Diffstat (limited to 'runtime/base/mutex.h')
| -rw-r--r-- | runtime/base/mutex.h | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/runtime/base/mutex.h b/runtime/base/mutex.h index 87e9525557..dc9b885bf7 100644 --- a/runtime/base/mutex.h +++ b/runtime/base/mutex.h @@ -103,10 +103,11 @@ class BaseMutex { BaseMutex(const char* name, LockLevel level); virtual ~BaseMutex(); - // Add this mutex to those owned by self, and perform appropriate checking. - // For this call only, self may also be another suspended thread. - void RegisterAsLocked(Thread* self); - void RegisterAsLockedImpl(Thread* self, LockLevel level); + // Add this mutex to those owned by self, and optionally perform lock order checking. Caller + // may wish to disable checking for trylock calls that cannot result in deadlock. For this call + // only, self may also be another suspended thread. + void RegisterAsLocked(Thread* self, bool check = kDebugLocking); + void RegisterAsLockedImpl(Thread* self, LockLevel level, bool check); void RegisterAsUnlocked(Thread* self); void RegisterAsUnlockedImpl(Thread* self, LockLevel level); @@ -183,7 +184,10 @@ class LOCKABLE Mutex : public BaseMutex { void ExclusiveLock(Thread* self) ACQUIRE(); void Lock(Thread* self) ACQUIRE() { ExclusiveLock(self); } - // Returns true if acquires exclusive access, false otherwise. + // Returns true if acquires exclusive access, false otherwise. The `check` argument specifies + // whether lock level checking should be performed. Should be defaulted unless we are using + // TryLock instead of Lock for deadlock avoidance. + template <bool kCheck = kDebugLocking> bool ExclusiveTryLock(Thread* self) TRY_ACQUIRE(true); bool TryLock(Thread* self) TRY_ACQUIRE(true) { return ExclusiveTryLock(self); } // Equivalent to ExclusiveTryLock, but retry for a short period before giving up. @@ -342,7 +346,7 @@ class SHARED_LOCKABLE ReaderWriterMutex : public BaseMutex { void ReaderLock(Thread* self) ACQUIRE_SHARED() { SharedLock(self); } // Try to acquire share of ReaderWriterMutex. - bool SharedTryLock(Thread* self) SHARED_TRYLOCK_FUNCTION(true); + bool SharedTryLock(Thread* self, bool check = kDebugLocking) SHARED_TRYLOCK_FUNCTION(true); // Release a share of the access. void SharedUnlock(Thread* self) RELEASE_SHARED() ALWAYS_INLINE; @@ -520,6 +524,18 @@ class SCOPED_CAPABILITY MutexLock { DISALLOW_COPY_AND_ASSIGN(MutexLock); }; +// Pretend to acquire a mutex for checking purposes, without actually doing so. Use with +// extreme caution when it is known the condition that the mutex would guard against cannot arise. +class SCOPED_CAPABILITY FakeMutexLock { + public: + explicit FakeMutexLock(Mutex& mu) ACQUIRE(mu) NO_THREAD_SAFETY_ANALYSIS {} + + ~FakeMutexLock() RELEASE() NO_THREAD_SAFETY_ANALYSIS {} + + private: + DISALLOW_COPY_AND_ASSIGN(FakeMutexLock); +}; + // Scoped locker/unlocker for a ReaderWriterMutex that acquires read access to mu upon // construction and releases it upon destruction. class SCOPED_CAPABILITY ReaderMutexLock { |