| |
|
 |
|
 |
|
|
|
| |
|
|
xen-devel
Re: [Xen-devel] [RFC] irq rate limit
On Wed, 2009-09-09 at 16:48 +0800, Keir Fraser wrote:
> On 09/09/2009 09:48, "Qing He" <qing.he@xxxxxxxxx> wrote:
>
> > This is a poc patch of guest irq ratelimit. The main motivation is
> > to ensure Xen's responsiveness during an irq storm, that caused by
> > improper hardware or drivers. If one interrupt is fired at a high
> > rate (>10k/10ms in the poc), it is disabled until the next periodic
> > timer_fn. A global generation counter is used to minimize overhead.
>
> What's the generation counter for? Why not just zero desc->rl_cnt in the
> timer handler?
If zeroing desc->rl_cnt in the timer handler, we have to zero that of
all irqs. If the numbers of possible irqs is big or sparse, it's a bit
painful.
Also, possibly it needs to be moved out of irq_desc and use atomic_t to
avoid spinlocking every irq_desc in the timer handler.
Thanks,
Qing
>
> -- Keir
>
>
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
|
|
| |
|
Home