[Bug 26500] Suggestion: throw out custom realization and use pthread_mutex_t

[wine-bugs at winehq.org]

http://bugs.winehq.org/show_bug.cgi?id=26500

--- Comment #6 from Vladimir Voznesensky <vvoznesensky at gmail.com> 2011-03-22 04:16:14 CDT ---
(In reply to comment #5)
> (In reply to comment #4)
> > Please, look _carefully_ at pthread_mutex_lock realization. It uses both
> > futexes and events!
> ...
> > lock variable is used for futex AND event is used for kernel synchronization!
> 
> How does it make this bug more valid?

Windows implementation does not have to busy wait forever. Look
http://msdn.microsoft.com/en-us/library/ms682530.aspx :

Spinning means that when a thread tries to acquire a critical section that is
locked, the thread enters a loop, checks to see if the lock is released, and if
the lock is not released, the thread goes to sleep. ... if the critical section
is unavailable, the calling thread spins dwSpinCount times before performing a
wait operation on a semaphore that is associated with the critical section. If
the critical section becomes free during the spin operation, the calling thread
avoids the wait operation.

As you can see, a kernel synchro object is used in Windows for waiting the
thread owning the lock. The same behaviour (except spinning) is realized in
libpthread. So, why should WineLib have a very different suboptimal behaviour?

-- 
Configure bugmail: http://bugs.winehq.org/userprefs.cgi?tab=email
Do not reply to this email, post in Bugzilla using the
above URL to reply.
------- You are receiving this mail because: -------
You are watching all bug changes.