[PATCH 2/2] net: mv643xx_eth: use dma_wmb/rmb where appropriate

From: Jisheng Zhang
Date: Fri May 13 2016 - 08:03:46 EST


Update the mv643xx_eth driver to use the dma_rmb/wmb calls instead of
the full barriers in order to improve performance.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
---
drivers/net/ethernet/marvell/mv643xx_eth.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mv643xx_eth.c b/drivers/net/ethernet/marvell/mv643xx_eth.c
index c6d8124..13b71e3 100644
--- a/drivers/net/ethernet/marvell/mv643xx_eth.c
+++ b/drivers/net/ethernet/marvell/mv643xx_eth.c
@@ -536,7 +536,7 @@ static int rxq_process(struct rx_queue *rxq, int budget)
cmd_sts = rx_desc->cmd_sts;
if (cmd_sts & BUFFER_OWNED_BY_DMA)
break;
- rmb();
+ dma_rmb();

skb = rxq->rx_skb[rxq->rx_curr_desc];
rxq->rx_skb[rxq->rx_curr_desc] = NULL;
@@ -647,9 +647,9 @@ static int rxq_refill(struct rx_queue *rxq, int budget)
DMA_FROM_DEVICE);
rx_desc->buf_size = size;
rxq->rx_skb[rx] = skb;
- wmb();
+ dma_wmb();
rx_desc->cmd_sts = BUFFER_OWNED_BY_DMA | RX_ENABLE_INTERRUPT;
- wmb();
+ dma_wmb();

/*
* The hardware automatically prepends 2 bytes of
@@ -889,7 +889,7 @@ static int txq_submit_tso(struct tx_queue *txq, struct sk_buff *skb,
skb_tx_timestamp(skb);

/* ensure all other descriptors are written before first cmd_sts */
- wmb();
+ dma_wmb();
first_tx_desc->cmd_sts = first_cmd_sts;

/* clear TX_END status */
@@ -994,7 +994,7 @@ static int txq_submit_skb(struct tx_queue *txq, struct sk_buff *skb,
skb_tx_timestamp(skb);

/* ensure all other descriptors are written before first cmd_sts */
- wmb();
+ dma_wmb();
desc->cmd_sts = cmd_sts;

/* clear TX_END status */
--
2.8.1