Re: [PATCH v2 net-next 3/9] net: mvneta: update mb bit before passing the xdp buffer to eBPF layer
From: Shay Agroskin <hidden>
Date: 2020-09-06 07:33:46
Also in:
bpf
Lorenzo Bianconi [off-list ref] writes:
quoted hunk ↗ jump to hunk
Update multi-buffer bit (mb) in xdp_buff to notify XDP/eBPF layer and XDP remote drivers if this is a "non-linear" XDP buffer. Access skb_shared_info only if xdp_buff mb is set Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> --- drivers/net/ethernet/marvell/mvneta.c | 37 +++++++++++++++------------ 1 file changed, 21 insertions(+), 16 deletions(-)diff --git a/drivers/net/ethernet/marvell/mvneta.cb/drivers/net/ethernet/marvell/mvneta.c index 832bbb8b05c8..4f745a2b702a 100644--- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c@@ -2027,11 +2027,11 @@ mvneta_xdp_put_buff(struct mvneta_port*pp, struct mvneta_rx_queue *rxq, struct xdp_buff *xdp, int sync_len, bool napi) { struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp); - int i; + int i, num_frames = xdp->mb ? sinfo->nr_frags : 0; page_pool_put_page(rxq->page_pool, virt_to_head_page(xdp->data), sync_len, napi); - for (i = 0; i < sinfo->nr_frags; i++) + for (i = 0; i < num_frames; i++) page_pool_put_full_page(rxq->page_pool, skb_frag_page(&sinfo->frags[i]), napi); } ...@@ -2175,6 +2175,7 @@ mvneta_run_xdp(struct mvneta_port *pp,struct mvneta_rx_queue *rxq, len = xdp->data_end - xdp->data_hard_start - pp->rx_offset_correction; data_len = xdp->data_end - xdp->data; - sinfo = xdp_get_shared_info_from_buff(xdp); - sinfo->nr_frags = 0; + xdp->mb = 0; *size = rx_desc->data_size - len; rx_desc->buf_phys_addr = 0;@@ -2269,7 +2267,7 @@ mvneta_swbm_add_rx_fragment(structmvneta_port *pp, struct mvneta_rx_desc *rx_desc, struct mvneta_rx_queue *rxq, struct xdp_buff *xdp, int *size, - struct page *page) + int *nfrags, struct page *page) { struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp); struct net_device *dev = pp->dev;@@ -2288,13 +2286,18 @@ mvneta_swbm_add_rx_fragment(structmvneta_port *pp, rx_desc->buf_phys_addr, len, dma_dir); - if (data_len > 0 && sinfo->nr_frags < MAX_SKB_FRAGS) { - skb_frag_t *frag = &sinfo->frags[sinfo->nr_frags]; + if (data_len > 0 && *nfrags < MAX_SKB_FRAGS) { + skb_frag_t *frag = &sinfo->frags[*nfrags]; skb_frag_off_set(frag, pp->rx_offset_correction); skb_frag_size_set(frag, data_len); __skb_frag_set_page(frag, page); - sinfo->nr_frags++; + *nfrags = *nfrags + 1;
nit, why do you use nfrags variable instead of sinfo->nr_frags (as
it was before this patch) ?
You doesn't seem to use the nfrags variable in the
caller function and you update nr_frags as well.
If it's used in a different patch (haven't
reviewed it all yet), maybe move it to that patch
? (sorry in advance if I missed the logic here)
+
+ if (rx_desc->status & MVNETA_RXD_LAST_DESC) {
+ sinfo->nr_frags = *nfrags;
+ xdp->mb = true;
+ }
rx_desc->buf_phys_addr = 0;
...