linux-kernel - Re: Question regarding mutex locking

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Date:	Wed, 28 Nov 2007 09:10:31 +0100
From:	Matthias Kaehlcke <matthias.kaehlcke@...il.com>
To:	Larry Finger <Larry.Finger@...inger.net>
Cc:	LKML <linux-kernel@...r.kernel.org>
Subject: Re: Question regarding mutex locking

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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