Re: Question regarding mutex locking

From: Matthias Kaehlcke
Date: Wed Nov 28 2007 - 03:10:36 EST


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.

--
Matthias Kaehlcke
Linux Application Developer
Barcelona

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