lkml.org 
[lkml]   [2020]   [Jan]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v2] virtio-net: Introduce extended RSC feature
On Mon, Jan 13, 2020 at 1:08 PM Jason Wang <jasowang@redhat.com> wrote:
>
>
> On 2020/1/13 下午4:17, Yuri Benditovich wrote:
> > VIRTIO_NET_F_RSC_EXT feature bit indicates that the device
> > is able to provide extended RSC information. When the feature
> > is negotiatede and 'gso_type' field in received packet is not
> > GSO_NONE, the device reports number of coalesced packets in
> > 'csum_start' field and number of duplicated acks in 'csum_offset'
> > field and sets VIRTIO_NET_HDR_F_RSC_INFO in 'flags' field.
> >
> > Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
>
>
> Hi Yuri:
>
> Is the feature used by Linux? If yes, it's better to include the real user.
>

It is not used by Linux. Mainly needed for certification under Windows.

>
> > ---
> > include/uapi/linux/virtio_net.h | 10 +++++++++-
> > 1 file changed, 9 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h
> > index a3715a3224c1..2bdd26f8a4ed 100644
> > --- a/include/uapi/linux/virtio_net.h
> > +++ b/include/uapi/linux/virtio_net.h
> > @@ -56,7 +56,7 @@
> > #define VIRTIO_NET_F_MQ 22 /* Device supports Receive Flow
> > * Steering */
> > #define VIRTIO_NET_F_CTRL_MAC_ADDR 23 /* Set MAC address */
> > -
> > +#define VIRTIO_NET_F_RSC_EXT 61 /* Provides extended RSC info */
>
>
> Is this better to keep the newline around?

No problem, let's wait until the rest is accepted.

>
>
> > #define VIRTIO_NET_F_STANDBY 62 /* Act as standby for another device
> > * with the same MAC.
> > */
> > @@ -104,6 +104,7 @@ struct virtio_net_config {
> > struct virtio_net_hdr_v1 {
> > #define VIRTIO_NET_HDR_F_NEEDS_CSUM 1 /* Use csum_start, csum_offset */
> > #define VIRTIO_NET_HDR_F_DATA_VALID 2 /* Csum is valid */
> > +#define VIRTIO_NET_HDR_F_RSC_INFO 4 /* rsc_ext data in csum_ fields */
> > __u8 flags;
> > #define VIRTIO_NET_HDR_GSO_NONE 0 /* Not a GSO frame */
> > #define VIRTIO_NET_HDR_GSO_TCPV4 1 /* GSO frame, IPv4 TCP (TSO) */
> > @@ -118,6 +119,13 @@ struct virtio_net_hdr_v1 {
> > __virtio16 num_buffers; /* Number of merged rx buffers */
> > };
> >
> > +/*
> > + * if VIRTIO_NET_F_RSC_EXT feature has been negotiated and
> > + * VIRTIO_NET_HDR_F_RSC_INFO is set in RX packet
> > + */
> > +#define virtio_net_rsc_ext_num_packets csum_start
> > +#define virtio_net_rsc_ext_num_dupacks csum_offset
>
>
> This looks sub-optimal, it looks to me union is better?

This was discussed in v1, MST decided the define is better.

>
> Thanks
>
>
> > +
> > #ifndef VIRTIO_NET_NO_LEGACY
> > /* This header comes first in the scatter-gather list.
> > * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated, it must
>

\
 
 \ /
  Last update: 2020-01-13 13:33    [W:0.052 / U:28.756 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site