Re: [PATCH 10/13] remove aggressive idle balancing

["Siddha, Suresh B" <suresh.b.siddha@intel.com>]

On Thu, Feb 24, 2005 at 11:13:14PM +1100, Nick Piggin wrote:
> Ingo Molnar wrote:
> > * Nick Piggin <nickpiggin@yahoo.com.au> wrote:
> > 
> > 
> >> [PATCH 6/13] no aggressive idle balancing
> >>
> >> [PATCH 8/13] generalised CPU load averaging
> >> [PATCH 9/13] less affine wakups
> >> [PATCH 10/13] remove aggressive idle balancing
> > 
> > 
> > they look fine, but these are the really scary ones :-) Maybe we could
> > do #8 and #9 first, then #6+#10. But it's probably pointless to look at
> > these in isolation.
> > 
> 
> Oh yes, they are very scary and I guarantee they'll cause
> problems :P

By code inspection, I see an issue with this patch
	[PATCH 10/13] remove aggressive idle balancing

Why are we removing cpu_and_siblings_are_idle check from active_load_balance?
In case of SMT, we  want to give prioritization to an idle package while
doing active_load_balance(infact, active_load_balance will be kicked
mainly because there is an idle package) 

Just the re-addition of cpu_and_siblings_are_idle check to 
active_load_balance might not be enough. We somehow need to communicate 
this to move_tasks, otherwise can_migrate_task will fail and we will 
never be able to do active_load_balance.

thanks,
suresh