Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754198Ab0BRU0k (ORCPT ); Thu, 18 Feb 2010 15:26:40 -0500 Received: from one.firstfloor.org ([213.235.205.2]:59920 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750993Ab0BRU0h (ORCPT ); Thu, 18 Feb 2010 15:26:37 -0500 Date: Thu, 18 Feb 2010 21:26:27 +0100 From: Andi Kleen To: Luca Barbieri Cc: "H. Peter Anvin" , Andi Kleen , mingo@elte.hu, a.p.zijlstra@chello.nl, akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 09/10] x86-32: use SSE for atomic64_read/set if available Message-ID: <20100218202627.GH5964@basil.fritz.box> References: <1266406962-17463-1-git-send-email-luca@luca-barbieri.com> <1266406962-17463-10-git-send-email-luca@luca-barbieri.com> <87eikj54wp.fsf@basil.nowhere.org> <20100218101156.GE5964@basil.fritz.box> <4B7D5BB4.4000307@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 817 Lines: 23 > memcpy/memset/etc. (assuming SSE is the best option for these at least > on some processors) and checksums come to mind. Typically SSE advantages only come to play with very large data sets, and the kernel's are not big enough. I tried it some time ago. That said you can already use kernel_fpu_begin/end of course and it's used in some very rare cases. > Also non-temporal SSE moves might be useful for things like memory > compaction without clobbering caches. You don't need SSE for non temporal moves. -Andi -- ak@linux.intel.com -- Speaking for myself only. -- 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/