nfp: move temporary variables in nfp_net_tx_complete()

Move temporary variables in scope of the loop in nfp_net_tx_complete(),
and add a temp for txbuf software structure.  This saves us 0.2% of CPU.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index b54c6e4812295e095e0a8199bbc88c468c1da334..78c651f9f774a65de41e30b0835c07abaf0a2081 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -940,14 +940,10 @@ static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring, int budget)
 {
        struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
        struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
-       const struct skb_frag_struct *frag;
        struct netdev_queue *nd_q;
        u32 done_pkts = 0, done_bytes = 0;
-       struct sk_buff *skb;
-       int todo, nr_frags;
        u32 qcp_rd_p;
-       int fidx;
-       int idx;
+       int todo;
 
        if (tx_ring->wr_p == tx_ring->rd_p)
                return;
@@ -961,26 +957,33 @@ static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring, int budget)
        todo = D_IDX(tx_ring, qcp_rd_p - tx_ring->qcp_rd_p);
 
        while (todo--) {
+               const struct skb_frag_struct *frag;
+               struct nfp_net_tx_buf *tx_buf;
+               struct sk_buff *skb;
+               int fidx, nr_frags;
+               int idx;
+
                idx = D_IDX(tx_ring, tx_ring->rd_p++);
+               tx_buf = &tx_ring->txbufs[idx];
 
-               skb = tx_ring->txbufs[idx].skb;
+               skb = tx_buf->skb;
                if (!skb)
                        continue;
 
                nr_frags = skb_shinfo(skb)->nr_frags;
-               fidx = tx_ring->txbufs[idx].fidx;
+               fidx = tx_buf->fidx;
 
                if (fidx == -1) {
                        /* unmap head */
-                       dma_unmap_single(dp->dev, tx_ring->txbufs[idx].dma_addr,
+                       dma_unmap_single(dp->dev, tx_buf->dma_addr,
                                         skb_headlen(skb), DMA_TO_DEVICE);
 
-                       done_pkts += tx_ring->txbufs[idx].pkt_cnt;
-                       done_bytes += tx_ring->txbufs[idx].real_len;
+                       done_pkts += tx_buf->pkt_cnt;
+                       done_bytes += tx_buf->real_len;
                } else {
                        /* unmap fragment */
                        frag = &skb_shinfo(skb)->frags[fidx];
-                       dma_unmap_page(dp->dev, tx_ring->txbufs[idx].dma_addr,
+                       dma_unmap_page(dp->dev, tx_buf->dma_addr,
                                       skb_frag_size(frag), DMA_TO_DEVICE);
                }
 
@@ -988,9 +991,9 @@ static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring, int budget)
                if (fidx == nr_frags - 1)
                        napi_consume_skb(skb, budget);
 
-               tx_ring->txbufs[idx].dma_addr = 0;
-               tx_ring->txbufs[idx].skb = NULL;
-               tx_ring->txbufs[idx].fidx = -2;
+               tx_buf->dma_addr = 0;
+               tx_buf->skb = NULL;
+               tx_buf->fidx = -2;
        }
 
        tx_ring->qcp_rd_p = qcp_rd_p;