Re: [RFC PATCH v3 3/5] sched: nominate preferred wakeup cpu

[Srivatsa Vaddagiri <vatsa@in.ibm.com>]

On Tue, Nov 11, 2008 at 09:07:58AM -0500, Gregory Haskins wrote:
> > Would it make sense to place the preferred_wakeup_cpu stuff in the
> > root_domain structure we already have?
> >   
> 
> From the description, this is exactly what the root-domains were created
> to solve.
> 
> Vaidyanathan,  just declare your object in "struct root_domain" and
> initialize it in init_rootdomain() in kernel/sched.c, and then access it
> via rq->rd to take advantage of this infrastructure.  It will
> automatically follow any partitioning that happens to be configured.

If I understand correctly, we may want to have more than one preferred
cpu in a given sched domain, taking into account node topology i.e if a
given sched domain encompasses two nodes, then we may like to designate
2 preferred wakeup_cpu's, one per node. If that is the case, then
root_domain may not be of use here?

- vatsa