On 5/30/2024 10:47 AM, Bruno Haible wrote:
SRW locks are spin-locks. Since they are only pointer-sized, ReleaseSRWLockExclusive cannot notify other threads — unlike CRITICAL_SECTION. Therefore, AcquireSRWLockExclusive must busy-loop when the lock is already held.
No, they only spin briefly, before calling into the OS to sleep - see the article about their internals here: https://learn.microsoft.com/en-us/archive/msdn-magazine/2012/november/windows-with-c-the-evolution-of-synchronization-in-windows-and-c#slim-readerwriter-lock Alternatively, Windows already has an API for init-once i.e. https://learn.microsoft.com/en-us/windows/win32/sync/one-time-initialization -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
