similar to: [PATCH net-next 1/8] virtio_net: mergeable xdp: put old page immediately

On Wed, 22 Mar 2023 16:22:18 +0800, Yunsheng Lin <linyunsheng at huawei.com> wrote: > On 2023/3/22 11:03, Xuan Zhuo wrote: > > In the xdp implementation of virtio-net mergeable, it always checks > > whether two page is used and a page is selected to release. This is > > complicated for the processing of action, and be careful. > > > > In the entire process,

? 2023/3/28 20:04, Xuan Zhuo ??: > Separating the logic of preparation for xdp from receive_mergeable. > > The purpose of this is to simplify the logic of execution of XDP. > > The main logic here is that when headroom is insufficient, we need to > allocate a new page and calculate offset. It should be noted that if > there is new page, the variable page will refer to the new

Separating the logic of preparation for xdp from receive_mergeable. The purpose of this is to simplify the logic of execution of XDP. The main logic here is that when headroom is insufficient, we need to allocate a new page and calculate offset. It should be noted that if there is new page, the variable page will refer to the new page. Signed-off-by: Xuan Zhuo <xuanzhuo at

We used to reset during XDP set, the main reason is we need allocate extra headroom for header adjustment but there's no way to know the headroom of exist receive buffer. This works buy maybe complex and may cause the network down for a while which is bad for user experience. So this patch tries to avoid this by: - packing headroom into receive buffer ctx - check the headroom during XDP, and

We used to do data copy through xdp_linearize_page() for the buffer without sufficient headroom, it brings extra complexity without helping for the performance. So this patch remove it and switch to use generic XDP routine to handle this case. Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/net/virtio_net.c | 93 ++++++------------------------------------------ 1 file

On Tue, Mar 28, 2023 at 8:04?PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote: > > In the xdp implementation of virtio-net mergeable, it always checks > whether two page is used and a page is selected to release. This is > complicated for the processing of action, and be careful. > > In the entire process, we have such principles: > * If xdp_page is used (PASS, TX,

On Thu, 23 Mar 2023 15:24:38 +0800, Yunsheng Lin <linyunsheng at huawei.com> wrote: > On 2023/3/23 13:40, Jason Wang wrote: > >>> > >>>> > >>>> Also, it seems better to split the xdp_linearize_page() to two functions > >>>> as pskb_expand_head() and __skb_linearize() do, one to expand the headroom, > >>>> the other

In the xdp implementation of virtio-net mergeable, it always checks whether two page is used and a page is selected to release. This is complicated for the processing of action, and be careful. In the entire process, we have such principles: * If xdp_page is used (PASS, TX, Redirect), then we release the old page. * If it is a drop case, we will release two. The old page obtained from buf is

On Mon, Jul 17, 2017 at 08:44:00PM +0800, Jason Wang wrote: > We used to reset during XDP set, the main reason is we need allocate > extra headroom for header adjustment but there's no way to know the > headroom of exist receive buffer. This works buy maybe complex and may > cause the network down for a while which is bad for user > experience. So this patch tries to avoid this

On Mon, Jul 17, 2017 at 08:44:00PM +0800, Jason Wang wrote: > We used to reset during XDP set, the main reason is we need allocate > extra headroom for header adjustment but there's no way to know the > headroom of exist receive buffer. This works buy maybe complex and may > cause the network down for a while which is bad for user > experience. So this patch tries to avoid this

XDP_REDIRECT support for mergeable buffer was removed since commit 7324f5399b06 ("virtio_net: disable XDP_REDIRECT in receive_mergeable() case"). This is because we don't reserve enough tailroom for struct skb_shared_info which breaks XDP assumption. Other complaints are, the complex linearize logic and EWMA estimation may increase the possibility of linearizing. Signed-off-by:

On Thu, Mar 01, 2018 at 11:19:04AM +0800, Jason Wang wrote: > XDP_REDIRECT support for mergeable buffer was removed since commit > 7324f5399b06 ("virtio_net: disable XDP_REDIRECT in receive_mergeable() > case"). This is because we don't reserve enough tailroom for struct > skb_shared_info which breaks XDP assumption. Other complaints are, the > complex linearize logic

On Thu, 1 Mar 2018 11:19:04 +0800 Jason Wang <jasowang at redhat.com> wrote: > XDP_REDIRECT support for mergeable buffer was removed since commit > 7324f5399b06 ("virtio_net: disable XDP_REDIRECT in receive_mergeable() > case"). This is because we don't reserve enough tailroom for struct > skb_shared_info which breaks XDP assumption. Other complaints are, the >

We don't put page during linearizing, the would cause leaking when xmit through XDP_TX or the packet exceeds PAGE_SIZE. Fix them by put page accordingly. Also decrease the number of buffers during linearizing to make sure caller can free buffers correctly when packet exceeds PAGE_SIZE. With this patch, we won't get OOM after linearize huge number of packets. Cc: John Fastabend

On Tue, Mar 28, 2023 at 8:04?PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote: > > At present, we have two similar logic to perform the XDP prog. > > Therefore, this PATCH separates the code of executing XDP, which is > conducive to later maintenance. > > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > --- > drivers/net/virtio_net.c | 142

On Tue, 4 Apr 2023 13:04:02 +0800, Jason Wang <jasowang at redhat.com> wrote: > On Mon, Apr 3, 2023 at 12:17?PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote: > > > > On Mon, 3 Apr 2023 10:43:03 +0800, Jason Wang <jasowang at redhat.com> wrote: > > > On Tue, Mar 28, 2023 at 8:04?PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote: > > >

On Tue, Apr 4, 2023 at 2:22?PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote: > > On Tue, 4 Apr 2023 13:04:02 +0800, Jason Wang <jasowang at redhat.com> wrote: > > On Mon, Apr 3, 2023 at 12:17?PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote: > > > > > > On Mon, 3 Apr 2023 10:43:03 +0800, Jason Wang <jasowang at redhat.com> wrote: > >

On Tue, Apr 4, 2023 at 2:55?PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote: > > On Tue, 4 Apr 2023 14:35:05 +0800, Jason Wang <jasowang at redhat.com> wrote: > > On Tue, Apr 4, 2023 at 2:22?PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote: > > > > > > On Tue, 4 Apr 2023 13:04:02 +0800, Jason Wang <jasowang at redhat.com> wrote: > >

On Wed, Mar 08, 2023 at 04:13:12PM +0800, Yunsheng Lin wrote: > On 2023/3/8 15:14, Xuan Zhuo wrote: > > On Wed, 8 Mar 2023 14:59:36 +0800, Yunsheng Lin <linyunsheng at huawei.com> wrote: > >> On 2023/3/8 10:49, Xuan Zhuo wrote: > >>> If the queue of xdp xmit is not an independent queue, then when the xdp > >>> xmit used all the desc, the xmit from

XDP_REDIRECT support for mergeable buffer was removed since commit 7324f5399b06 ("virtio_net: disable XDP_REDIRECT in receive_mergeable() case"). This is because we don't reserve enough tailroom for struct skb_shared_info which breaks XDP assumption. So this patch fixes this by reserving enough tailroom and using fixed size of rx buffer. Signed-off-by: Jason Wang <jasowang at