Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752128AbZA1R2O (ORCPT ); Wed, 28 Jan 2009 12:28:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751104AbZA1R14 (ORCPT ); Wed, 28 Jan 2009 12:27:56 -0500 Received: from smtp3.ultrahosting.com ([74.213.175.254]:35693 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751052AbZA1R1z (ORCPT ); Wed, 28 Jan 2009 12:27:55 -0500 Date: Wed, 28 Jan 2009 11:50:21 -0500 (EST) From: Christoph Lameter X-X-Sender: cl@qirst.com To: Rusty Russell cc: Tejun Heo , Ingo Molnar , Herbert Xu , akpm@linux-foundation.org, hpa@zytor.com, brgerst@gmail.com, ebiederm@xmission.com, travis@sgi.com, linux-kernel@vger.kernel.org, steiner@sgi.com, hugh@veritas.com, "David S. Miller" , netdev@vger.kernel.org, Mathieu Desnoyers Subject: Re: [PATCH] percpu: add optimized generic percpu accessors In-Reply-To: <200901282108.51864.rusty@rustcorp.com.au> Message-ID: References: <20090115183942.GA6325@elte.hu> <200901271213.18605.rusty@rustcorp.com.au> <497E705B.5000302@kernel.org> <200901282108.51864.rusty@rustcorp.com.au> 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: 942 Lines: 23 On Wed, 28 Jan 2009, Rusty Russell wrote: > AFAICT we'll need a hybrid: HAVE_NMISAFE_CPUOPS, and if not, use atomic_t > in ftrace (which isn't NMI safe on parisc or sparc/32 anyway, but I don't think we care). Right. > Other than the shouting, I liked Christoph's system: > - CPU_INC = always safe (eg. local_irq_save/per_cpu(i)++/local_irq_restore) > - _CPU_INC = not safe against interrupts (eg. get_cpu/per_cpu(i)++/put_cpu) > - __CPU_INC = not safe against anything (eg. per_cpu(i)++) > > I prefer the name 'local' to the name 'cpu', but I'm not hugely fussed. The term cpu is meaning multiple things at this point. So yes it may be better to go with glibc naming of thread local space. -- 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/