From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423232AbWF1JGI (ORCPT ); Wed, 28 Jun 2006 05:06:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1423235AbWF1JGI (ORCPT ); Wed, 28 Jun 2006 05:06:08 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:46287 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1423232AbWF1JGH (ORCPT ); Wed, 28 Jun 2006 05:06:07 -0400 Date: Wed, 28 Jun 2006 11:00:58 +0200 From: Ingo Molnar To: Andi Kleen Cc: Paul Jackson , 76306.1226@compuserve.com, linux-kernel@vger.kernel.org, torvalds@osdl.org, drepper@redhat.com, roland@redhat.com, jakub@redhat.com Subject: Re: [RFC, patch] i386: vgetcpu(), take 2 Message-ID: <20060628090058.GA15328@elte.hu> References: <200606210329_MC3-1-C305-E008@compuserve.com> <20060621081539.GA14227@elte.hu> <20060627224433.fb726e0c.pj@sgi.com> <200606281053.15681.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200606281053.15681.ak@suse.de> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -3.1 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-3.1 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_50 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts 0.0 BAYES_50 BODY: Bayesian spam probability is 40 to 60% [score: 0.5000] 0.2 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Andi Kleen wrote: > On Wednesday 28 June 2006 07:44, Paul Jackson wrote: > > > but my gut feeling is that we should add a proper sys_get_cpu() syscall > > > > Yes - this should be for more or less all arch's. > > The whole point of the original implementation is to do a fast > architecture specific call. A slow generic call isn't very useful. it's useful in terms of userspace uniformity. It's alot easier to expose such APIs via glibc if there's a generic implementation everywhere. Obviously every arch is encouraged to optimize it into a vsyscall. Ingo