From 13df4c666c551bba97618d7e3908c2ecd03ceefb Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Thu, 3 Nov 2016 17:12:05 +0000 Subject: [PATCH] nfp: reorganize nfp_net_rx() to get packet offsets early Calculate packet offsets early in nfp_net_rx() so that we will be able to use them in upcoming XDP handler. While at it move relevant variables into the loop scope. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller --- .../ethernet/netronome/nfp/nfp_net_common.c | 68 ++++++++++--------- 1 file changed, 36 insertions(+), 32 deletions(-) diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c index 506362729607..2ab63661a6fd 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c @@ -1383,16 +1383,17 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget) { struct nfp_net_r_vector *r_vec = rx_ring->r_vec; struct nfp_net *nn = r_vec->nfp_net; - unsigned int data_len, meta_len; - struct nfp_net_rx_buf *rxbuf; - struct nfp_net_rx_desc *rxd; - dma_addr_t new_dma_addr; struct sk_buff *skb; int pkts_polled = 0; - void *new_frag; int idx; while (pkts_polled < budget) { + unsigned int meta_len, data_len, data_off, pkt_len, pkt_off; + struct nfp_net_rx_buf *rxbuf; + struct nfp_net_rx_desc *rxd; + dma_addr_t new_dma_addr; + void *new_frag; + idx = rx_ring->rd_p & (rx_ring->cnt - 1); rxd = &rx_ring->rxds[idx]; @@ -1408,6 +1409,34 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget) pkts_polled++; rxbuf = &rx_ring->rxbufs[idx]; + /* < meta_len > + * <-- [rx_offset] --> + * --------------------------------------------------------- + * | [XX] | metadata | packet | XXXX | + * --------------------------------------------------------- + * <---------------- data_len ---------------> + * + * The rx_offset is fixed for all packets, the meta_len can vary + * on a packet by packet basis. If rx_offset is set to zero + * (_RX_OFFSET_DYNAMIC) metadata starts at the beginning of the + * buffer and is immediately followed by the packet (no [XX]). + */ + meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK; + data_len = le16_to_cpu(rxd->rxd.data_len); + pkt_len = data_len - meta_len; + + if (nn->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC) + pkt_off = meta_len; + else + pkt_off = nn->rx_offset; + data_off = NFP_NET_RX_BUF_HEADROOM + pkt_off; + + /* Stats update */ + u64_stats_update_begin(&r_vec->rx_sync); + r_vec->rx_pkts++; + r_vec->rx_bytes += pkt_len; + u64_stats_update_end(&r_vec->rx_sync); + skb = build_skb(rxbuf->frag, nn->fl_bufsz); if (unlikely(!skb)) { nfp_net_rx_drop(r_vec, rx_ring, rxbuf, NULL); @@ -1424,33 +1453,8 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget) nfp_net_rx_give_one(rx_ring, new_frag, new_dma_addr); - /* < meta_len > - * <-- [rx_offset] --> - * --------------------------------------------------------- - * | [XX] | metadata | packet | XXXX | - * --------------------------------------------------------- - * <---------------- data_len ---------------> - * - * The rx_offset is fixed for all packets, the meta_len can vary - * on a packet by packet basis. If rx_offset is set to zero - * (_RX_OFFSET_DYNAMIC) metadata starts at the beginning of the - * buffer and is immediately followed by the packet (no [XX]). - */ - meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK; - data_len = le16_to_cpu(rxd->rxd.data_len); - - if (nn->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC) - skb_reserve(skb, NFP_NET_RX_BUF_HEADROOM + meta_len); - else - skb_reserve(skb, - NFP_NET_RX_BUF_HEADROOM + nn->rx_offset); - skb_put(skb, data_len - meta_len); - - /* Stats update */ - u64_stats_update_begin(&r_vec->rx_sync); - r_vec->rx_pkts++; - r_vec->rx_bytes += skb->len; - u64_stats_update_end(&r_vec->rx_sync); + skb_reserve(skb, data_off); + skb_put(skb, pkt_len); if (nn->fw_ver.major <= 3) { nfp_net_set_hash_desc(nn->netdev, skb, rxd);