From ae67bf0188cbb9d1786bdfcca9e1976cb36ee327 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Fri, 13 Mar 2015 12:11:06 -0700 Subject: [PATCH] net: bcmgenet: update ring producer index and buffer count in xmit There is no need to have both bcmgenet_xmit_single() and bcmgenet_xmit_frag() perform a free_bds decrement and a prod_index increment by one. In case one of these functions fails to map a SKB or fragment for transmit, we will return and exit bcmgenet_xmit() with an error. We can therefore safely use our local copy of nr_frags to know by how much we should decrement the number of free buffers available, and by how much the producer count must be incremented and do this in the tail of bcmgenet_xmit(). Signed-off-by: Florian Fainelli Acked-by: Petri Gynther Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/genet/bcmgenet.c | 18 +++++------------- 1 file changed, 5 insertions(+), 13 deletions(-) diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c index 875967e8d719..53c916ea06a2 100644 --- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c +++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c @@ -1130,11 +1130,6 @@ static int bcmgenet_xmit_single(struct net_device *dev, dmadesc_set(priv, tx_cb_ptr->bd_addr, mapping, length_status); - /* Decrement total BD count and advance our write pointer */ - ring->free_bds -= 1; - ring->prod_index += 1; - ring->prod_index &= DMA_P_INDEX_MASK; - return 0; } @@ -1173,11 +1168,6 @@ static int bcmgenet_xmit_frag(struct net_device *dev, (frag->size << DMA_BUFLENGTH_SHIFT) | dma_desc_flags | (priv->hw_params->qtag_mask << DMA_TX_QTAG_SHIFT)); - - ring->free_bds -= 1; - ring->prod_index += 1; - ring->prod_index &= DMA_P_INDEX_MASK; - return 0; } @@ -1321,9 +1311,11 @@ static netdev_tx_t bcmgenet_xmit(struct sk_buff *skb, struct net_device *dev) skb_tx_timestamp(skb); - /* we kept a software copy of how much we should advance the TDMA - * producer index, now write it down to the hardware - */ + /* Decrement total BD count and advance our write pointer */ + ring->free_bds -= nr_frags + 1; + ring->prod_index += nr_frags + 1; + ring->prod_index &= DMA_P_INDEX_MASK; + bcmgenet_tdma_ring_writel(priv, ring->index, ring->prod_index, TDMA_PROD_INDEX); -- 2.11.0