Re: sched: Improve load balancing in the presence of idle CPUs

[Jason Low <jason.low2@hp.com>]

On Thu, 2015-04-09 at 12:32 +0530, Srikar Dronamraju wrote:

> rq->idle_balance gets updated at every scheduler_tick() but the only user of
> rq->idle_balance (after your change) seems to be run_rebalance_domains().
> Now can we remove rq->idle_balance. This would mean we would have to
> call idle_cpu() instead of using rq->idle_balance in
> run_rebalance_domains(). (similar to what your above change)
> 
> That way we can reduce the rq struct size and we might end up calling
> idle_cpu() lesser number of times.

Yeah, we may also include another patch for that.

Taking a look at rebalance_domains(), we're already updating the "idle"
value using idle_cpu() after attempting load balancing anyway, so there
may not be much point in the extra parameter.