From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.lst.de (verein.lst.de [213.95.11.210]) (using TLSv1 with cipher EDH-RSA-DES-CBC3-SHA (168/168 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 593162BF12 for ; Wed, 5 Jan 2005 20:36:20 +1100 (EST) Date: Wed, 5 Jan 2005 10:26:59 +0100 From: Christoph Hellwig To: Jim Nelson Message-ID: <20050105092659.GA27103@lst.de> References: <20050104214048.21749.85722.89116@localhost.localdomain> <41DB4E99.3060200@didntduck.org> <41DB5476.9040103@cwazy.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <41DB5476.9040103@cwazy.co.uk> Cc: linuxppc-dev@ozlabs.org, Brian Gerst , paulus@samba.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/7] ppc: remove cli()/sti() from arch/ppc/* List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, Jan 04, 2005 at 09:44:06PM -0500, Jim Nelson wrote: > Brian Gerst wrote: > > >James Nelson wrote: > > > >>This series of patches is to remove the last cli()/sti() function > >>calls in arch/ppc. > >> > >>These are the only instances in active code that grep could find. > > > > > >Are you sure none of these need real spinlocks instead of just > >disabling interrupts? > > > >-- > > Brian Gerst > > > These are for single-processor systems, mostly evaluation boards and > embedded processors. I coudn't find any reference to multiprocessor > setups for the processors in question after a peruse of the code or a > quick google on the boards in question. think CONFIG_PREEMPT. In either case a spinlock becomes lock_irq_disable in the !SMP, !PREEMPT case but it documents the intention a whole lot better. Also you're locking only in a single plpace which is a ***BIG*** warning sign. At least look at the other users of the data structure, it's extremly likely they'll need locking aswell.