From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nathan Lynch Subject: Re: Re: [RFC 5/6]clean cpu state after hotremove CPU Date: Mon, 4 Apr 2005 17:46:20 -0500 Message-ID: <20050404224620.GD3611@otto> References: <1112580367.4194.344.camel@sli10-desk.sh.intel.com> <20050404052844.GB3611@otto> <1112593338.4194.362.camel@sli10-desk.sh.intel.com> <20050404153345.GC3611@otto> <1112652864.3757.31.camel@desktop.cunningham.myip.net.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1112652864.3757.31.camel-r49W/1Cwd2ff0s6lnCXPX/uOuaPYTxhvJwvTLr3MMZM@public.gmane.org> Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Nigel Cunningham Cc: Li Shaohua , lkml , ACPI List , Zwane Mwaikambo , Len Brown , Pavel Machek List-Id: linux-acpi@vger.kernel.org Hi Nigel! On Tue, Apr 05, 2005 at 08:14:25AM +1000, Nigel Cunningham wrote: > > On Tue, 2005-04-05 at 01:33, Nathan Lynch wrote: > > > Yes, exactly. Someone who understand do_exit please help clean up the > > > code. I'd like to remove the idle thread, since the smpboot code will > > > create a new idle thread. > > > > I'd say fix the smpboot code so that it doesn't create new idle tasks > > except during boot. > > Would that mean that CPUs that were physically hotplugged wouldn't get > idle threads? No, that wouldn't work. I am saying that there's little to gain by adding all this complexity for destroying the idle tasks when it's fairly simple to create num_possible_cpus() - 1 idle tasks* to accommodate any additional cpus which may come along. This is what ppc64 does now, and it should be feasible on any architecture which supports cpu hotplug. Nathan * num_possible_cpus() - 1 because the idle task for the boot cpu is created in sched_init. ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click