| Message ID | 20211208140702.642741-10-alexandr.lobakin@intel.com (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: intel: napi_alloc_skb() vs metadata | expand |
>-----Original Message----- >From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of >Alexander Lobakin >Sent: Wednesday, December 8, 2021 7:37 PM >To: intel-wired-lan@lists.osuosl.org >Cc: Song Liu <songliubraving@fb.com>; Alexei Starovoitov <ast@kernel.org>; >Andrii Nakryiko <andrii@kernel.org>; Daniel Borkmann ><daniel@iogearbox.net>; John Fastabend <john.fastabend@gmail.com>; >Jesper Dangaard Brouer <brouer@redhat.com>; Yonghong Song ><yhs@fb.com>; Jesper Dangaard Brouer <hawk@kernel.org>; KP Singh ><kpsingh@kernel.org>; Jakub Kicinski <kuba@kernel.org>; >netdev@vger.kernel.org; linux-kernel@vger.kernel.org; David S. Miller ><davem@davemloft.net>; Björn Töpel <bjorn@kernel.org>; >bpf@vger.kernel.org; Martin KaFai Lau <kafai@fb.com> >Subject: [Intel-wired-lan] [PATCH v4 net-next 9/9] ixgbe: respect metadata on >XSK Rx to skb > >For now, if the XDP prog returns XDP_PASS on XSK, 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. >net_prefetch() xdp->data_meta and align the copy size to speed-up >memcpy() a little and better match ixgbe_costruct_skb(). > >Fixes: d0bcacd0a130 ("ixgbe: add AF_XDP zero-copy Rx support") >Suggested-by: Jesper Dangaard Brouer <brouer@redhat.com> >Suggested-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> >Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com> >Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> >--- > drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > Tested-by: Sandeep Penigalapati <sandeep.penigalapati@intel.com>
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c index db20dc4c2488..ec1e2da72676 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c @@ -209,19 +209,25 @@ bool ixgbe_alloc_rx_buffers_zc(struct ixgbe_ring *rx_ring, u16 count) static struct sk_buff *ixgbe_construct_skb_zc(struct ixgbe_ring *rx_ring, const struct xdp_buff *xdp) { + unsigned int totalsize = xdp->data_end - xdp->data_meta; unsigned int metasize = xdp->data - xdp->data_meta; - unsigned int datasize = xdp->data_end - xdp->data; struct sk_buff *skb; + net_prefetch(xdp->data_meta); + /* allocate a skb to store the frags */ - skb = __napi_alloc_skb(&rx_ring->q_vector->napi, datasize, + skb = __napi_alloc_skb(&rx_ring->q_vector->napi, totalsize, GFP_ATOMIC | __GFP_NOWARN); if (unlikely(!skb)) return NULL; - memcpy(__skb_put(skb, datasize), xdp->data, datasize); - if (metasize) + memcpy(__skb_put(skb, totalsize), xdp->data_meta, + ALIGN(totalsize, sizeof(long))); + + if (metasize) { skb_metadata_set(skb, metasize); + __skb_pull(skb, metasize); + } return skb; }
For now, if the XDP prog returns XDP_PASS on XSK, 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. net_prefetch() xdp->data_meta and align the copy size to speed-up memcpy() a little and better match ixgbe_costruct_skb(). Fixes: d0bcacd0a130 ("ixgbe: add AF_XDP zero-copy Rx support") Suggested-by: Jesper Dangaard Brouer <brouer@redhat.com> Suggested-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com> --- drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)