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xdp: recycle Page Pool backed skbs built from XDP frames

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__xdp_build_skb_from_frame() state(d):

/* Until page_pool get SKB return path, release DMA here */

Page Pool got skb pages recycling in April 2021, but missed this
function.

xdp_release_frame() is relevant only for Page Pool backed frames and it
detaches the page from the corresponding page_pool in order to make it
freeable via page_frag_free(). It can instead just mark the output skb
as eligible for recycling if the frame is backed by a pp. No change for
other memory model types (the same condition check as before).
cpumap redirect and veth on Page Pool drivers now become zero-alloc (or
almost).

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/r/20230313215553.1045175-4-aleksander.lobakin@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Alexander Lobakin 2023-03-13 22:55:52 +01:00 committed by Alexei Starovoitov
parent 2c854e5fcd
commit 9c94bbf9a8
1 changed files with 2 additions and 2 deletions
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4
net/core/xdp.c
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@ -658,8 +658,8 @@ struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
* - RX ring dev queue index (skb_record_rx_queue)
*/
/* Until page_pool get SKB return path, release DMA here */
xdp_release_frame(xdpf);
if (xdpf->mem.type == MEM_TYPE_PAGE_POOL)
skb_mark_for_recycle(skb);
/* Allow SKB to reuse area used by xdp_frame */
xdp_scrub_frame(xdpf);