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
You must have a plan. If you don't have a plan,
you'll become part of somebody else's plan
.''`.
using free software / Debian GNU/Linux | http://debian.org : :' :
`. `'`
gpg --keyserver pgp.mit.edu --recv-keys 47D8E5D4 `-
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
