Re: [ACPI] Re: [RFC 5/6]clean cpu state after hotremove CPU

Nigel Cunningham
2005-04-05T00:15:13Z

Hi.

On Tue, 2005-04-05 at 08:46, Nathan Lynch wrote:
> 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.

Ah. Ta. I was a little confused :>

Nigel

> * num_possible_cpus() - 1 because the idle task for the boot cpu is
> created in sched_init.
--
Nigel Cunningham
Software Engineer, Canberra, Australia
http://www.cyclades.com
Bus: +61 (2) 6291 9554; Hme: +61 (2) 6292 8028; Mob: +61 (417) 100 574

Maintainer of Suspend2 Kernel Patches http://suspend2.net