RE: [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring

Sherry Sun
2020-10-26T03:04:50Z

Hi Greg & Christoph,

> Subject: Re: [PATCH V3 2/4] misc: vop: do not allocate and reassign the used
> ring
>
> On Thu, Oct 22, 2020 at 01:06:36PM +0800, Sherry Sun wrote:
> > We don't need to allocate and reassign the used ring here and remove
> > the used_address_updated flag.Since RC has allocated the entire vring,
> > including the used ring. Simply add the corresponding offset can get
> > the used ring address.
>
> Someone needs to verify this vs the existing intel implementations.

Hi Greg, @gregkh@linuxfoundation.org, sorry I don't have the Intel MIC devices so cannot test it, do you know anyone who can help test this patch changes on the Intel MIC platform? Thanks.

>
> > - used = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
> > - get_order(vdev->used_size[index]));
> > + used = va + PAGE_ALIGN(sizeof(struct vring_desc) *
> > +le16_to_cpu(config.num) +
>
> This adds an over 80 char line.

Hi Christoph, will fix it in V4, thanks.

>
> > + vdev->used[index] = config.address + PAGE_ALIGN(sizeof(struct
> > +vring_desc) * le16_to_cpu(config.num) +
>
> Again.

Best regards
Sherry