* Siddha, Suresh B <[EMAIL PROTECTED]> wrote:
> In the presence of SMT, newly idle balance was never happening for
> multi-core and SMP domains(even when both the logical siblings are
> idle).
>
> If thread 0 is already idle and when thread 1 is about to go to idle,
> newly idle load balance always think that one of the threads is not
> idle and skips doing the newly idle load balance for multi-core and
> SMP domains.
>
> This is because of the idle_cpu() macro, which checks if the current
> process on a cpu is an idle process. But this is not the case for the
> thread doing the load_balance_newidle().
>
> Fix this by using runqueue's nr_running field instead of idle_cpu().
> And also skip the logic of 'only one idle cpu in the group will be
> doing load balancing' during newly idle case.
ah, indeed - good catch! I've checked the other uses of idle_cpu() and
those seem to be fine. I've added your patch to my queue.
Ingo
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