Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261246AbVCWJsx (ORCPT ); Wed, 23 Mar 2005 04:48:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261233AbVCWJsx (ORCPT ); Wed, 23 Mar 2005 04:48:53 -0500 Received: from arnor.apana.org.au ([203.14.152.115]:42761 "EHLO arnor.apana.org.au") by vger.kernel.org with ESMTP id S261246AbVCWJss (ORCPT ); Wed, 23 Mar 2005 04:48:48 -0500 Date: Wed, 23 Mar 2005 20:48:05 +1100 To: paulmck@us.ibm.com Cc: mingo@elte.hu, linux-kernel@vger.kernel.org, simlo@phys.au.dk Subject: Re: [patch] Real-Time Preemption, -RT-2.6.12-rc1-V0.7.41-07 Message-ID: <20050323094805.GA14012@gondor.apana.org.au> References: <20050323061601.GE1294@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.6+20040907i From: Herbert Xu Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1282 Lines: 32 On Wed, Mar 23, 2005 at 08:40:58PM +1100, Herbert Xu wrote: > Paul E. McKenney wrote: > > > > +void rcu_read_unlock(void) > > +{ > > + int cpu; > > + > > + if (--current->rcu_read_lock_nesting == 0) { > > + atomic_dec(¤t->rcu_data->active_readers); > > + /* > > + * Check whether we have reached quiescent state. > > + * Note! This is only for the local CPU, not for > > + * current->rcu_data's CPU [which typically is the > > + * current CPU, but may also be another CPU]. > > + */ > > + cpu = get_cpu(); > > > > And need an smp_mb() here, again for non-x86 CPUs. > > The atomic_dec is already a barrier. Sorry, I was confused. atomic_dec is not a barrier of course. -- Visit Openswan at http://www.openswan.org/ Email: Herbert Xu ~{PmV>HI~} Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt - 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/