Re: [PATCH V2 2/6] vhost_net: use vhost_add_used_and_signal_n() in vhost_zerocopy_signal_used()

Jason Wang
2013-09-02T06:28:37Z

On 09/02/2013 01:50 PM, Michael S. Tsirkin wrote:
> On Fri, Aug 30, 2013 at 12:29:18PM +0800, Jason Wang wrote:
>> > We tend to batch the used adding and signaling in vhost_zerocopy_callback()
>> > which may result more than 100 used buffers to be updated in
>> > vhost_zerocopy_signal_used() in some cases. So wwitch to use
> switch

Ok.
>> > vhost_add_used_and_signal_n() to avoid multiple calls to
>> > vhost_add_used_and_signal(). Which means much more less times of used index
>> > updating and memory barriers.
> pls put info on perf gain in commit log too
>

Sure.