On 12/10/2012 02:10 AM, Oleg Nesterov wrote:

On 12/10, Srivatsa S. Bhat wrote:

quoted

On 12/10/2012 01:18 AM, Oleg Nesterov wrote:

quoted

quoted

-		if (preempt && rq != p_rq)
+		if (preempt && rq != p_rq && cpu_online(task_cpu(p)))

Why do we need this change?

Afaics, you could add BUG_ON(!cpu_online(...)) instead?

I am just curious.

Oh, I think that's a remnant of v1 (which needed readers to use
cpu_online_stable()). You're right, we don't need it.

Ah OK, thanks.

quoted

Or we could put a
BUG_ON instead, like you suggested.

IMHO it would be better to simply drop this chunk.

Sure, will drop it. Its distracting, if nothing else ;-)

Regards,
Srivatsa S. Bhat