On 03/15/11 09:50, Keir Fraser wrote:

On 15/03/2011 08:46, "Juergen Gross"<juergen.gross@xxxxxxxxxxxxxx> wrote:

It's not critical, and not affecting correctness. But with updating
idle_bias on the first invocation you're (on the right hardware)
basically guaranteeing the second invocation to return a
different CPU. That way, your loop will be run minimally three
times on such systems. I already find it odd to require two
iterations when previously this was a strait code path.

This was wrong. It was always required to hold the schedule lock of the
picked cpu as well, otherwise a race with cpu hotplug would be possible.

What would that race be? CPU offlining is done in stop_machine context.

Ahh, okay.
Juergen
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