Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932351AbVISHWe (ORCPT ); Mon, 19 Sep 2005 03:22:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932354AbVISHWe (ORCPT ); Mon, 19 Sep 2005 03:22:34 -0400 Received: from smtp206.mail.sc5.yahoo.com ([216.136.129.96]:11156 "HELO smtp206.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S932351AbVISHWd (ORCPT ); Mon, 19 Sep 2005 03:22:33 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Subject:From:To:Cc:In-Reply-To:References:Content-Type:Date:Message-Id:Mime-Version:X-Mailer:Content-Transfer-Encoding; b=fpu91WjUWvzN4xRKswq/C1KMNhsVdxeJMe9utJe2HKam+HFNzT+FwuHAj+BP0/Y31rDEuV9n5IKzFO29qWbiL5ukUfAWhFphZLfneI4fxwTyexo8EbKy2AA4ouqWI2dr42isbCIapjUURz4MXENYOb5W6NlWSDsnhfnUQMprG2w= ; Subject: Re: PATCH: Fix race in cpu_down (hotplug cpu) From: Nick Piggin To: Shaohua Li Cc: vatsa@in.ibm.com, Nigel Cunningham , Andrew Morton , Linus Torvalds , Zwane Mwaikambo , lkml , Rusty Russell , Ingo Molnar In-Reply-To: <1127113930.4087.6.camel@linux-hp.sh.intel.com> References: <59D45D057E9702469E5775CBB56411F171F7E0@pdsmsx406> <20050919051024.GA8653@in.ibm.com> <1127107887.3958.9.camel@linux-hp.sh.intel.com> <20050919055715.GE8653@in.ibm.com> <1127110271.9696.97.camel@localhost> <20050919062336.GA9466@in.ibm.com> <1127111830.4087.3.camel@linux-hp.sh.intel.com> <1127111784.5272.10.camel@npiggin-nld.site> <1127113930.4087.6.camel@linux-hp.sh.intel.com> Content-Type: text/plain Date: Mon, 19 Sep 2005 17:22:18 +1000 Message-Id: <1127114538.5272.16.camel@npiggin-nld.site> Mime-Version: 1.0 X-Mailer: Evolution 2.0.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1048 Lines: 32 On Mon, 2005-09-19 at 15:12 +0800, Shaohua Li wrote: > On Mon, 2005-09-19 at 16:36 +1000, Nick Piggin wrote: > > Ah, actually I have a patch which makes all CPU idle threads > > run with preempt disabled and only enable preempt when scheduling. > > Would that help? > It should solve the issue to me. Should we take care of the latency? > acpi_processor_idle might execute for a long time. > Oh really? I think yes, the latency should be taken care of because we want to be able to provide good latency even for !preempt kernels. If a solution can be found for acpi_processor_idle, that would be ideal. IMO it always felt kind of hackish to run the idle threads with preempt on. Thanks, Nick -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com - 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/