From: Arnd Bergmann <arnd@arndb.de>
To: Nathan Lynch <ntl@pobox.com>
Subject: Re: [PATCH 3/8] ppc64: add a watchdog driver for rtas
Date: Wed, 18 May 2005 16:39:51 +0200
User-Agent: KMail/1.7.2
Cc: linuxppc64-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>,
       linux-kernel@vger.kernel.org, Anton Blanchard <anton@samba.org>,
       Utz Bacher <utz.bacher@de.ibm.com>, Wim Van Sebroeck <wim@iguana.be>
References: <200505132117.37461.arnd@arndb.de> <200505180914.44336.arnd@arndb.de> <20050518144534.GA3723@otto>
In-Reply-To: <20050518144534.GA3723@otto>
MIME-Version: 1.0
Content-Type: text/plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: 8BIT
Content-Disposition: inline
Message-Id: <200505181639.52415.arnd@arndb.de>
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 808
Lines: 19

On Middeweken 18 Mai 2005 16:45, Nathan Lynch wrote:
> 
> > A semaphore would also be the wrong approach since we don't want
> > processes to block but instead to fail opening the watchdog twice.
> 
> I should have been more explicit. ?What I had in mind was using
> down_trylock and returning -EBUSY if it failed.

Well, that's also pointless. If the only operations you ever do
on a semaphore are down_trylock() and up(), you end up using
only the atomic variable in there while wasting a few bytes of
extra memory for storing the wait queue head ;-)

	Arnd <><
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/