RE: [Xen-devel] [PATCH4/6] cpuidle: remove hpet access in hpet_broadcast_exit

["Wei, Gang" <gang.wei@xxxxxxxxx>]

On Thursday, 2010-6-17 4:26 PM, Jan Beulich wrote:
>>>> On 17.06.10 at 09:38, "Wei, Gang" <gang.wei@xxxxxxxxx> wrote:
>> BTW, move the cpumask set out of critial section in
>> hpet_broadcast_enter to shorten it.
> 
> Could you explain why you can move it out of the locked section for
> _enter(), but can't for _exit() - this isn't obvious to me (and would
> perhaps deserve a comment in the sources).

Keeping cpumask clear within the locked section in _exit() to avoid 
handle_hpet_broadcast() to access other cpu's timer_deadline_start/end after 
the other cpu's mask was cleared. For set, there are no such issue. And cpumask 
set/clear it self should be atom type.

Jimmy
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel