Message ID | 20211207205536.563550-3-alexandr.lobakin@intel.com |
---|---|
State | Superseded |
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 > Lobakin, Alexandr > Sent: Wednesday, December 8, 2021 2:25 AM > To: intel-wired-lan@lists.osuosl.org > Cc: Andre Guedes <andre.guedes@intel.com>; Jesper Dangaard Brouer > <hawk@kernel.org>; Daniel Borkmann <daniel@iogearbox.net>; > netdev@vger.kernel.org; Krzysztof Kazimierczak > <krzysztof.kazimierczak@intel.com>; bpf@vger.kernel.org; John Fastabend > <john.fastabend@gmail.com>; Alexei Starovoitov <ast@kernel.org>; Brouer, > Jesper <brouer@redhat.com>; Björn Töpel <bjorn@kernel.org>; Jeff Kirsher > <jeffrey.t.kirsher@intel.com>; Jakub Kicinski <kuba@kernel.org>; linux- > kernel@vger.kernel.org; David S. Miller <davem@davemloft.net>; Vedang > Patel <vedang.patel@intel.com> > Subject: [Intel-wired-lan] [PATCH v3 net-next 2/9] i40e: 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 i40e_costruct_skb(). > > Fixes: 0a714186d3c0 ("i40e: 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/i40e/i40e_xsk.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > Tested-by: Kiran Bhandare <kiranx.bhandare@intel.com> A Contingent Worker at Intel
diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c index 9564906b7da8..0e8cf275e084 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c +++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c @@ -240,19 +240,25 @@ bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count) static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring, 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)) goto out; - 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); + } out: xsk_buff_free(xdp);