From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757548Ab2HVHya (ORCPT ); Wed, 22 Aug 2012 03:54:30 -0400 Received: from mga11.intel.com ([192.55.52.93]:57336 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757408Ab2HVHyN (ORCPT ); Wed, 22 Aug 2012 03:54:13 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.77,808,1336374000"; d="scan'208";a="183726431" Message-ID: <50349012.3010508@intel.com> Date: Wed, 22 Aug 2012 15:53:54 +0800 From: Alex Shi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:9.0) Gecko/20111229 Thunderbird/9.0 MIME-Version: 1.0 To: Jan Beulich CC: konrad.wilk@oracle.com, linux-kernel@vger.kernel.org, hpa@zytor.com Subject: Re: apparent regressions from TLB range flushing page set References: <503261F00200007800096710@nat28.tlf.novell.com> <5034516E.60908@intel.com> <50349BF6020000780008A4C6@nat28.tlf.novell.com> In-Reply-To: <50349BF6020000780008A4C6@nat28.tlf.novell.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/22/2012 03:44 PM, Jan Beulich wrote: >>>> Alex Shi 08/22/12 5:27 AM >>> >>> Second, the UV code doesn't flush the full range at all, it simply >>> ignores its 'end' parameter (and hence also the "all" indicator). >> >> Sure. the following rfc patch try to fix it. untested since no hardware. > > Sure - this needs to be looked at by a person knowing UV (and I would > have thought a change like the one we're discussing here would also > have required an ack from such a person), but ... > >> --- a/arch/x86/platform/uv/tlb_uv.c >> +++ b/arch/x86/platform/uv/tlb_uv.c >> @@ -280,12 +280,12 @@ static void bau_process_message(struct msg_desc *mdp, struct bau_control *bcp, >> /* >> * This must be a normal message, or retry of a normal message >> */ >> - if (msg->address == TLB_FLUSH_ALL) { >> + if (msg->end == 0) { > > How would "end" end up being 0 here? Don't you rather mean "start and > end on the same page"? yes, > And even if you do, aren't you then losing the > intended optimization? Sure, TLB optimization is relatively complex and specific on different hardware. I am not sure this platform needs this, and even so, I can not give reasonable flushall_shift value. So, it is better to recover the system as before.