[PATCH v4 net-next 3/9] ice: respect metadata in legacy-rx/ice_construct_skb()
From: Alexander Lobakin <hidden>
Date: 2021-12-08 14:08:08
Also in:
bpf, intel-wired-lan, lkml
Subsystem:
intel ethernet drivers, networking drivers, the rest · Maintainers:
Tony Nguyen, Przemek Kitszel, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
In "legacy-rx" mode represented by ice_construct_skb(), we can still use XDP (and XDP metadata), but after XDP_PASS the metadata will be lost as it doesn't get copied to the skb. Copy it along with the frame headers. Account its size on skb allocation, and when copying just treat it as a part of the frame and do a pull after to "move" it to the "reserved" zone. Point net_prefetch() to xdp->data_meta instead of data. This won't change anything when the meta is not here, but will save some cache misses otherwise. Suggested-by: Jesper Dangaard Brouer <redacted> Suggested-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Signed-off-by: Alexander Lobakin <redacted> Reviewed-by: Michal Swiatkowski <redacted> --- drivers/net/ethernet/intel/ice/ice_txrx.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c
index bc3ba19dc88f..d724b6376c43 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx.c
+++ b/drivers/net/ethernet/intel/ice/ice_txrx.c@@ -968,15 +968,17 @@ static struct sk_buff * ice_construct_skb(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf, struct xdp_buff *xdp) { + unsigned int metasize = xdp->data - xdp->data_meta; unsigned int size = xdp->data_end - xdp->data; unsigned int headlen; struct sk_buff *skb; /* prefetch first cache line of first page */ - net_prefetch(xdp->data); + net_prefetch(xdp->data_meta); /* allocate a skb to store the frags */ - skb = __napi_alloc_skb(&rx_ring->q_vector->napi, ICE_RX_HDR_SIZE, + skb = __napi_alloc_skb(&rx_ring->q_vector->napi, + ICE_RX_HDR_SIZE + metasize, GFP_ATOMIC | __GFP_NOWARN); if (unlikely(!skb)) return NULL;
@@ -988,8 +990,13 @@ ice_construct_skb(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf, headlen = eth_get_headlen(skb->dev, xdp->data, ICE_RX_HDR_SIZE); /* align pull length to size of long to optimize memcpy performance */ - memcpy(__skb_put(skb, headlen), xdp->data, ALIGN(headlen, - sizeof(long))); + memcpy(__skb_put(skb, headlen + metasize), xdp->data_meta, + ALIGN(headlen + metasize, sizeof(long))); + + if (metasize) { + skb_metadata_set(skb, metasize); + __skb_pull(skb, metasize); + } /* if we exhaust the linear part then add what is left as a frag */ size -= headlen;
--
2.33.1