On Thu, 20 Apr 2023 13:16:21 +0200 Lorenzo Bianconi wrote:
> @@ -727,17 +729,21 @@ static int veth_convert_skb_to_xdp_buff(struct veth_rq *rq,
> goto drop;
>
> /* Allocate skb head */
> - page = alloc_page(GFP_ATOMIC | __GFP_NOWARN);
> + if (rq->page_pool)
There's some condition under which we can get to XDP enabled but no
pool?
> + page = page_pool_dev_alloc_pages(rq->page_pool);
> if (!page)
> goto drop;
>
> nskb = build_skb(page_address(page), PAGE_SIZE);
> if (!nskb) {
> - put_page(page);
> + page_pool_put_full_page(rq->page_pool, page, false);
You can recycle direct, AFAIU the basic rule of thumb is that it's
always safe to recycle direct from the context which allocates from
the pool.
> goto drop;
> }
>
> skb_reserve(nskb, VETH_XDP_HEADROOM);
> + skb_copy_header(nskb, skb);
> + skb_mark_for_recycle(nskb);
> +
> size = min_t(u32, skb->len, max_head_size);
> if (skb_copy_bits(skb, 0, nskb->data, size)) {
> consume_skb(nskb);
> @@ -745,16 +751,17 @@ static int veth_convert_skb_to_xdp_buff(struct veth_rq *rq,
> }
> skb_put(nskb, size);
>
> - skb_copy_header(nskb, skb);
> head_off = skb_headroom(nskb) - skb_headroom(skb);
> skb_headers_offset_update(nskb, head_off);
>
> /* Allocate paged area of new skb */
> off = size;
> len = skb->len - off;
> + page = NULL;
Why do you clear the page pointer?
--
pw-bot: cr
