Messages in this thread | | | Date | Wed, 28 Nov 2007 16:00:55 +0100 | From | Matthias Kaehlcke <> | Subject | Re: Question regarding mutex locking |
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El Wed, Nov 28, 2007 at 08:46:51AM -0600 Larry Finger ha dit:
> Matthias Kaehlcke wrote: > > El Tue, Nov 27, 2007 at 10:37:00PM -0600 Larry Finger ha dit: > > > >> If a particular routine needs to lock a mutex, but it may be entered with that mutex already locked, > >> would the following code be SMP safe? > >> > >> hold_lock = mutex_trylock() > >> > >> ... > >> > >> if (hold_lock) > >> mutex_unlock() > > > > this is wont work, a mutex must not be released from another > > context than the one that acquired it. > > I thought that mutex_trylock() returned 1 if it got the lock and 0 if not. If that is true, wouldn't > the if statement only unlock if the lock was obtained in this routine?
you're right, sorry i read to fast and interpreted that you want to release the mutex in any case
-- Matthias Kaehlcke Linux Application Developer Barcelona
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