Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937366AbXHPAxZ (ORCPT ); Wed, 15 Aug 2007 20:53:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763937AbXHPAxI (ORCPT ); Wed, 15 Aug 2007 20:53:08 -0400 Received: from rhun.apana.org.au ([64.62.148.172]:1660 "EHLO arnor.apana.org.au" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1764241AbXHPAxG (ORCPT ); Wed, 15 Aug 2007 20:53:06 -0400 Date: Thu, 16 Aug 2007 08:51:56 +0800 From: Herbert Xu To: Satyam Sharma Cc: Segher Boessenkool , horms@verge.net.au, Stefan Richter , Linux Kernel Mailing List , "Paul E. McKenney" , ak@suse.de, netdev@vger.kernel.org, cfriesen@nortel.com, Heiko Carstens , rpjday@mindspring.com, jesper.juhl@gmail.com, linux-arch@vger.kernel.org, Andrew Morton , zlynx@acm.org, clameter@sgi.com, schwidefsky@de.ibm.com, Chris Snook , davem@davemloft.net, Linus Torvalds , wensong@linux-vs.org, wjiang@resilience.com Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures Message-ID: <20070816005156.GA29698@gondor.apana.org.au> References: <20070815145207.GA23106@gondor.apana.org.au> <46C3253F.5090707@s5r6.in-berlin.de> <20070815162722.GD9645@linux.vnet.ibm.com> <20070815185724.GH9645@linux.vnet.ibm.com> <2d2eeab6276cab2e6cc5830d36a43b98@kernel.crashing.org> <20070816003226.GA29491@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1061 Lines: 25 On Thu, Aug 16, 2007 at 06:28:42AM +0530, Satyam Sharma wrote: > > > The udelay itself certainly should have some form of cpu_relax in it. > > Yes, a form of barrier() must be present in mdelay() or udelay() itself > as you say, having it in __const_udelay() is *not* enough (superflous > actually, considering it is already a separate translation unit and > invisible to the compiler). As long as __const_udelay does something which has the same effect as barrier it is enough even if it's in the same unit. As a matter of fact it does on i386 where __delay either uses rep_nop or asm/volatile. Cheers, -- 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/