Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 31 Dec 2001 15:29:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 31 Dec 2001 15:29:22 -0500 Received: from noodles.codemonkey.org.uk ([62.49.180.5]:18840 "EHLO noodles.codemonkey.org.uk") by vger.kernel.org with ESMTP id ; Mon, 31 Dec 2001 15:29:16 -0500 Date: Mon, 31 Dec 2001 20:31:22 +0000 From: Dave Jones To: Manfred Spraul Cc: Andrew Morton , Linux Kernel Subject: Re: [patch] Prefetching file_read_actor() Message-ID: <20011231203122.A17288@suse.de> Mail-Followup-To: Dave Jones , Manfred Spraul , Andrew Morton , Linux Kernel In-Reply-To: <20011231033220.A1686@suse.de> <3C2FFB2F.D02095A2@zip.com.au> <3C3044D3.EBEF6657@colorfullife.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3C3044D3.EBEF6657@colorfullife.com> User-Agent: Mutt/1.3.22.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 31, 2001 at 11:58:27AM +0100, Manfred Spraul wrote: > > What happens if a prefetch spills over the end of the page and > > faults? > Doesn't hurt, prefetch instruction never cause page faults. > BUT: Prefetch doesn't preload the TLB. If the TLB entry for the kmap is > not in the TLB, all prefetch instructions are treated as nops.(on pIII). Wasn't this the reason for the voodoo workaround we have in the mmx version of fast_copy_page() ? Dave. -- Dave Jones. http://www.codemonkey.org.uk SuSE Labs. - 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/