From 1a1d74d378b13ad3f93e8975a0ade0980a49d28b Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 31 Oct 2016 20:43:17 +0000 Subject: [PATCH] nfp: use AND instead of modulo to get ring indexes We already force ring sizes to be power of 2 so replace modulo operations with AND (size - 1) in index calculations. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller --- drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c index b43d2dbae368..7225ab61a120 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c @@ -778,7 +778,7 @@ static int nfp_net_tx(struct sk_buff *skb, struct net_device *netdev) if (dma_mapping_error(&nn->pdev->dev, dma_addr)) goto err_free; - wr_idx = tx_ring->wr_p % tx_ring->cnt; + wr_idx = tx_ring->wr_p & (tx_ring->cnt - 1); /* Stash the soft descriptor of the head then initialize it */ txbuf = &tx_ring->txbufs[wr_idx]; @@ -822,7 +822,7 @@ static int nfp_net_tx(struct sk_buff *skb, struct net_device *netdev) if (dma_mapping_error(&nn->pdev->dev, dma_addr)) goto err_unmap; - wr_idx = (wr_idx + 1) % tx_ring->cnt; + wr_idx = (wr_idx + 1) & (tx_ring->cnt - 1); tx_ring->txbufs[wr_idx].skb = skb; tx_ring->txbufs[wr_idx].dma_addr = dma_addr; tx_ring->txbufs[wr_idx].fidx = f; @@ -917,7 +917,7 @@ static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring) todo = qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p; while (todo--) { - idx = tx_ring->rd_p % tx_ring->cnt; + idx = tx_ring->rd_p & (tx_ring->cnt - 1); tx_ring->rd_p++; skb = tx_ring->txbufs[idx].skb; @@ -992,7 +992,7 @@ nfp_net_tx_ring_reset(struct nfp_net *nn, struct nfp_net_tx_ring *tx_ring) int nr_frags, fidx, idx; struct sk_buff *skb; - idx = tx_ring->rd_p % tx_ring->cnt; + idx = tx_ring->rd_p & (tx_ring->cnt - 1); skb = tx_ring->txbufs[idx].skb; nr_frags = skb_shinfo(skb)->nr_frags; fidx = tx_ring->txbufs[idx].fidx; @@ -1129,7 +1129,7 @@ static void nfp_net_rx_give_one(struct nfp_net_rx_ring *rx_ring, { unsigned int wr_idx; - wr_idx = rx_ring->wr_p % rx_ring->cnt; + wr_idx = rx_ring->wr_p & (rx_ring->cnt - 1); /* Stash SKB and DMA address away */ rx_ring->rxbufs[wr_idx].frag = frag; @@ -1164,7 +1164,7 @@ static void nfp_net_rx_ring_reset(struct nfp_net_rx_ring *rx_ring) unsigned int wr_idx, last_idx; /* Move the empty entry to the end of the list */ - wr_idx = rx_ring->wr_p % rx_ring->cnt; + wr_idx = rx_ring->wr_p & (rx_ring->cnt - 1); last_idx = rx_ring->cnt - 1; rx_ring->rxbufs[wr_idx].dma_addr = rx_ring->rxbufs[last_idx].dma_addr; rx_ring->rxbufs[wr_idx].frag = rx_ring->rxbufs[last_idx].frag; @@ -1413,7 +1413,7 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget) int idx; while (pkts_polled < budget) { - idx = rx_ring->rd_p % rx_ring->cnt; + idx = rx_ring->rd_p & (rx_ring->cnt - 1); rxd = &rx_ring->rxds[idx]; if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD)) -- 2.11.0