From: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
To: Larry Finger <Larry.Finger@lwfinger.net>
Cc: LKML <linux-kernel@vger.kernel.org>
Subject: Re: Question regarding mutex locking
Date: Wed, 28 Nov 2007 09:10:31 +0100 [thread overview]
Message-ID: <20071128081031.GF20238@traven> (raw)
In-Reply-To: <474CF06C.8020208@lwfinger.net>
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
Don't walk behind me, I may not lead
Don't walk in front of me, I may not follow
Just walk beside me and be my friend
(Albert Camus)
.''`.
using free software / Debian GNU/Linux | http://debian.org : :' :
`. `'`
gpg --keyserver pgp.mit.edu --recv-keys 47D8E5D4 `-
next prev parent reply other threads:[~2007-11-28 8:10 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-28 4:37 Question regarding mutex locking Larry Finger
2007-11-28 8:10 ` Matthias Kaehlcke [this message]
2007-11-28 14:46 ` Larry Finger
2007-11-28 15:00 ` Matthias Kaehlcke
2007-11-28 15:22 ` Andreas Schwab
2007-11-28 15:41 ` Larry Finger
2007-11-28 22:45 ` Jarek Poplawski
2007-11-28 22:56 ` Jarek Poplawski
2007-11-28 23:07 ` Jarek Poplawski
2007-11-28 23:33 ` Stephen Hemminger
2007-11-29 6:40 ` Jarek Poplawski
2007-11-30 1:13 ` Bryan O'Sullivan
[not found] <fa.C9TdvYAhY8SablNc39IpD8WDnNM@ifi.uio.no>
2007-11-28 4:53 ` Robert Hancock
2007-11-28 5:19 ` Larry Finger
2007-11-29 2:34 ` David Schwartz
2007-11-29 7:56 ` Jarek Poplawski
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