Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262177AbVDMDbg (ORCPT ); Tue, 12 Apr 2005 23:31:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262613AbVDMD1a (ORCPT ); Tue, 12 Apr 2005 23:27:30 -0400 Received: from smtp201.mail.sc5.yahoo.com ([216.136.129.91]:14239 "HELO smtp201.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S262595AbVDMD0r (ORCPT ); Tue, 12 Apr 2005 23:26:47 -0400 Message-ID: <425C914A.3070604@yahoo.com.au> Date: Wed, 13 Apr 2005 13:26:02 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.6) Gecko/20050324 Debian/1.7.6-1 X-Accept-Language: en MIME-Version: 1.0 To: davidm@hpl.hp.com CC: Ingo Molnar , "David S. Miller" , tony.luck@intel.com, lkml Subject: Re: [patch] sched: unlocked context-switches References: <3R6Ir-89Y-23@gated-at.bofh.it> <20050409070738.GA5444@elte.hu> <16983.33049.962002.335198@napali.hpl.hp.com> <20050409155810.593d8f7b.davem@davemloft.net> <20050410064324.GA24596@elte.hu> <16987.7956.806699.617633@napali.hpl.hp.com> <1113271965.5090.24.camel@npiggin-nld.site> <16988.477.530205.502023@napali.hpl.hp.com> In-Reply-To: <16988.477.530205.502023@napali.hpl.hp.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1178 Lines: 30 David Mosberger wrote: >>>>>>On Tue, 12 Apr 2005 12:12:45 +1000, Nick Piggin said: > > > >> Now, Ingo says that the order is reversed with his patch, i.e., > >> switch_mm() happens after switch_to(). That means flush_tlb_mm() > >> may now see a current->active_mm which hasn't really been > >> activated yet. > > Nick> If that did bother you, could you keep track of the actually > Nick> activated mm in your arch code? Or would that involve more > Nick> arch hooks and general ugliness in the scheduler? > > I'm sorry, but I don't see the point of this. We are already tracking > care of ownership, just not atomically. What's the point of putting > another level of (atomic) tracking on top of it. That seems > exceedingly ugly. > Well, you were worried about it not being atomic. So that would be the point, but I agree it would probably be exceedingly ugly if implemented. Nick - 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/