Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753114AbZJPQbq (ORCPT ); Fri, 16 Oct 2009 12:31:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752267AbZJPQbp (ORCPT ); Fri, 16 Oct 2009 12:31:45 -0400 Received: from smtp2.ultrahosting.com ([74.213.174.253]:53118 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751822AbZJPQbp (ORCPT ); Fri, 16 Oct 2009 12:31:45 -0400 Date: Fri, 16 Oct 2009 12:23:51 -0400 (EDT) From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Tejun Heo cc: "Luck, Tony" , "linux-kernel@vger.kernel.org" , "rusty@rustcorp.com.au" , "mingo@redhat.com" , Thomas Gleixner , "akpm@linux-foundation.org" , "rostedt@goodmis.org" , "hpa@zytor.com" , "cebbert@redhat.com" Subject: Re: [PATCH 13/16] percpu: remove per_cpu__ prefix. In-Reply-To: <4AD6E29B.8000506@kernel.org> Message-ID: References: <1255500125-3210-1-git-send-email-tj@kernel.org> <1255500125-3210-14-git-send-email-tj@kernel.org> <57C9024A16AD2D4C97DC78E552063EA3E32264A8@orsmsx505.amr.corp.intel.com> <57C9024A16AD2D4C97DC78E552063EA3E3226704@orsmsx505.amr.corp.intel.com> <4AD6E29B.8000506@kernel.org> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 842 Lines: 19 On Thu, 15 Oct 2009, Tejun Heo wrote: > __ia64_per_cpu_var() is slightly different from this_cpu_read() in > that the former only works for percpu variables which fall on the > first percpu page - ie. static percpu vars in the kernel image. So, > __ia64_per_cpu_var() is a bit more efficient than this_cpu_read() as > it doesn't have to compute the address. > > So, what we can do is to leave the macro alone for now and then add > sparse annotation to it later in the patch as it's basically another > specialized accessor. How does that sound? Ok. The macro would be arch specific anyways. -- 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/