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 <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2016-11-03 17:12:05 +00:00 committed by David S. Miller
parent 164d1e9e5d
commit 13df4c666c
1 changed files with 36 additions and 32 deletions

View File

@ -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);