diff options
| -rw-r--r-- | runtime/base/mutex.cc | 1 | ||||
| -rw-r--r-- | runtime/base/mutex.h | 2 |
2 files changed, 2 insertions, 1 deletions
diff --git a/runtime/base/mutex.cc b/runtime/base/mutex.cc index 0abe9667f8..26a665bd41 100644 --- a/runtime/base/mutex.cc +++ b/runtime/base/mutex.cc @@ -463,6 +463,7 @@ void Mutex::ExclusiveLock(Thread* self) { done = state_and_contenders_.CompareAndSetWeakAcquire(cur_state, cur_state | kHeldMask); } else { // Failed to acquire, hang up. + // We don't hold the mutex: GetExclusiveOwnerTid() is usually, but not always, correct. ScopedContentionRecorder scr(this, SafeGetTid(self), GetExclusiveOwnerTid()); // Empirically, it appears important to spin again each time through the loop; if we // bother to go to sleep and wake up, we should be fairly persistent in trying for the diff --git a/runtime/base/mutex.h b/runtime/base/mutex.h index e3d89e7449..9185f79ab7 100644 --- a/runtime/base/mutex.h +++ b/runtime/base/mutex.h @@ -394,7 +394,7 @@ class EXPORT SHARED_LOCKABLE ReaderWriterMutex : public BaseMutex { // Id associated with exclusive owner. No memory ordering semantics if called from a thread other // than the owner. Returns 0 if the lock is not held. Returns either 0 or -1 if it is held by - // one or more readers. + // one or more readers. Not reliable unless the mutex is held. pid_t GetExclusiveOwnerTid() const; void Dump(std::ostream& os) const override; |