From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760742AbXKNEQM (ORCPT ); Tue, 13 Nov 2007 23:16:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755862AbXKNEP5 (ORCPT ); Tue, 13 Nov 2007 23:15:57 -0500 Received: from relay1.sgi.com ([192.48.171.29]:46391 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755775AbXKNEP4 (ORCPT ); Tue, 13 Nov 2007 23:15:56 -0500 Date: Tue, 13 Nov 2007 20:15:55 -0800 (PST) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Andi Kleen cc: David Miller , akpm@linux-foundation.org, linux-mm@vger.kernel.org, linux-kernel@vger.kernel.org, dada1@cosmosbay.com, schwidefsky@de.ibm.com Subject: Re: [patch 01/28] cpu alloc: The allocator In-Reply-To: Message-ID: References: <20071106195144.983665861@sgi.com> <20071106195157.878563669@sgi.com> <20071113.031510.151440585.davem@davemloft.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hmmm.. I have v2 in preparation here that puts the pda and the per cpu data into the cpu_alloc area. Thus gs: can be used to access all per cpu data. Any ideas how to abstract out the pda operations? Wasnt local_t supposed to be able to do atomic ops on cpu data? Is there an segment register version of local_t? I want also to have cmpxchg xchg etc that are all atomic without requiring any interrupt disable or preempt disable. cpu_alloc allows pointer arithmetic on cpu area pointers. The segment prefix can then be used to select the appropriate area. Guess I need also to add an arch configuration guide to V2 as well so that the other arches can do similar tricks and emphasize that the static default that requires bss is only suitable for small systems.