Re: [PATCH] cpuhotplug: introduce try_get_online_cpus() take 2
From: Gautham R Shenoy
Date: Mon Jun 08 2009 - 00:20:10 EST
Hi Paul,
On Fri, Jun 05, 2009 at 08:37:14AM -0700, Paul E. McKenney wrote:
>
> One question for Gautham Shenoy -- are non-atomic CPU-hotplug notifiers
> always invoked from the task that did the cpu_hotplug_begin()?
Except for the notifiers handling two events, rest of the notifiers
are always invoked from the task that did the cpu_hotplug_begin().
The two events are CPU_DYING which is called from the context of the
stop_machine_thread and CPU_STARTING which is called from the context of
the idle thread on the CPU that has just come up. The notifiers handling
these two events are expected to be atomic.
> If so, well and good. If not, then it would not be possible to
> expedite RCU grace periods from within CPU-hotplug notifiers.
I hope this would be good enough :-)
>
> Thanx, Paul
>
--
Thanks and Regards
gautham
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/