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

Ashok Raj
2005-04-04T23:04:55Z

On Mon, Apr 04, 2005 at 03:46:20PM -0700, 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
>
> 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.
>

In ia64 we create idle threads on demand if one is not available for the same
logical cpu number, and re-used when the same logical cpu number is re-used.

just a minor improvement, i also thought about idle exit, but wasnt worth
anything in return.

Cheers,
ashok