Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S275296AbTHMSqz (ORCPT ); Wed, 13 Aug 2003 14:46:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S275356AbTHMSoz (ORCPT ); Wed, 13 Aug 2003 14:44:55 -0400 Received: from crosslink-village-512-1.bc.nu ([81.2.110.254]:23289 "EHLO dhcp23.swansea.linux.org.uk") by vger.kernel.org with ESMTP id S275355AbTHMSom (ORCPT ); Wed, 13 Aug 2003 14:44:42 -0400 Subject: Re: 2.6.0-test3-mm1: scheduling while atomic (ext3?) From: Alan Cox To: Andi Kleen Cc: Linux Kernel Mailing List In-Reply-To: <20030813153235.GB21081@wotan.suse.de> References: <20030813025542.32429718.akpm@osdl.org.suse.lists.linux.kernel> <1060772769.8009.4.camel@localhost.localdomain.suse.lists.linux.kernel> <20030813042544.5064b3f4.akpm@osdl.org.suse.lists.linux.kernel> <1060774803.8008.24.camel@localhost.localdomain.suse.lists.linux.kernel> <1060778924.8008.39.camel@localhost.localdomain> <20030813131457.GD32290@wotan.suse.de> <1060783794.8008.62.camel@dhcp23.swansea.linux.org.uk> <20030813142055.GC9179@wotan.suse.de> <1060788009.8957.5.camel@dhcp23.swansea.linux.org.uk> <20030813153235.GB21081@wotan.suse.de> Content-Type: text/plain Content-Transfer-Encoding: 7bit Message-Id: <1060800263.9130.29.camel@dhcp23.swansea.linux.org.uk> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.3 (1.4.3-3) Date: 13 Aug 2003 19:44:24 +0100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1303 Lines: 31 On Mer, 2003-08-13 at 16:32, Andi Kleen wrote: > The AMD slides assume all very big data sets ;-) > > I would recommend to remove it. I'll do some timings when I get a moment - the prefetching mmx copy was a win (and faster than the others for small data as well as large on the K7-550 (really a K7 not "Athlon" 8)) way back when. > > What else checks the 3Dnow bit ? > > Nothing in kernel AFAIK, but it's possible that it is used by user space > reading /proc/cpuinfo. DaveJ and your docs are right on 3dnow it turns out so sorry about that and ignore me on prefetchw, its just the prefetch side thats 3 way. > BTW we saw it mainly in the x86-64 copy_*_user and csum_copy_* functions > which do also prefetches. LTP would sometimes trigger it when it tests > how the kernel behaves with invalid addresses. But it happened very > rarely in the dcache hash too. But still it's hard to trigger, the > linked list one is very hard to hit. I tried to reproduce it in user space, > but failed. The LTP one is much easier, but still not that common. Thanks - 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/