From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756487AbYKERz7 (ORCPT ); Wed, 5 Nov 2008 12:55:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752857AbYKERzv (ORCPT ); Wed, 5 Nov 2008 12:55:51 -0500 Received: from rv-out-0506.google.com ([209.85.198.232]:9424 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752344AbYKERzu (ORCPT ); Wed, 5 Nov 2008 12:55:50 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=xozQLoaPwRKgYGX0Pmipayb61rg3TgcF1lC5Apsj73VlME0AEUNG9L+6TfgudghNI1 D1innA8rT/UYFpll8zdCLB9/yq8k8mhtABrZcLIjFx9t33EAII1PfV4d8YnS/waLvL6Y MXEumAzXGLOdeB9aBtgfYXxcdCy1YXS1WEK8k= Message-ID: <8bd0f97a0811050955k5fa31ccanc738b66348b83250@mail.gmail.com> Date: Wed, 5 Nov 2008 12:55:49 -0500 From: "Mike Frysinger" To: "Greg KH" Subject: Re: [PATCH] UIO: only call pgprot_noncached if defined Cc: "Hans J. Koch" , "Mike Frysinger" , linux-kernel@vger.kernel.org In-Reply-To: <20081105174234.GA10223@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <1225301177-21406-1-git-send-email-vapier@gentoo.org> <20081105113610.GA6382@local> <20081105163334.GA8473@suse.de> <8bd0f97a0811050933m13addb7eiddb963bfdf4d7416@mail.gmail.com> <20081105174234.GA10223@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 5, 2008 at 12:42, Greg KH wrote: > On Wed, Nov 05, 2008 at 12:33:37PM -0500, Mike Frysinger wrote: >> On Wed, Nov 5, 2008 at 11:33, Greg KH wrote: >> > On Wed, Nov 05, 2008 at 12:36:11PM +0100, Hans J. Koch wrote: >> >> There seem to be archs that cannot easily implement a sensible >> >> pgprot_noncached() function, so we should merge this patch. UIO doesn't >> >> compile on these archs right now. >> > >> > No, we should fix those arches to have that function at least NULLed >> > out. Isn't there only one, Blackfin? Putting #ifdefs in .c files is >> > not something we really want to do if at all possible. >> >> that was my question. this function isnt documented. if the hardware >> doesnt support it, is the right thing really for the arch to lie to >> drivers and not actually give back cached settings even though it >> asked for non-cached ? > > Probably not, it sounds like the arch needs to be fixed :) i'd agree, but we're dealing with reality here: we're talking no-mmu and we can not do caching on a per-page basis while maintaining anything resembling usable performance. -mike