From 8d86c61ae41d9068fd5e5cc01a4abd53c4fe3ab5 Mon Sep 17 00:00:00 2001 From: Santiago Leon Date: Fri, 3 Sep 2010 18:28:25 +0000 Subject: [PATCH] ibmveth: Add rx_copybreak For small packets, create a new skb and copy the packet into it so we avoid tearing down and creating a TCE entry. Signed-off-by: Anton Blanchard Signed-off-by: Santiago Leon Signed-off-by: David S. Miller --- drivers/net/ibmveth.c | 29 +++++++++++++++++++++++------ 1 file changed, 23 insertions(+), 6 deletions(-) diff --git a/drivers/net/ibmveth.c b/drivers/net/ibmveth.c index fc6e2cf879c0..c236c8af3367 100644 --- a/drivers/net/ibmveth.c +++ b/drivers/net/ibmveth.c @@ -122,6 +122,11 @@ module_param(tx_copybreak, uint, 0644); MODULE_PARM_DESC(tx_copybreak, "Maximum size of packet that is copied to a new buffer on transmit"); +static unsigned int rx_copybreak __read_mostly = 128; +module_param(rx_copybreak, uint, 0644); +MODULE_PARM_DESC(rx_copybreak, + "Maximum size of packet that is copied to a new buffer on receive"); + struct ibmveth_stat { char name[ETH_GSTRING_LEN]; int offset; @@ -1002,8 +1007,6 @@ static int ibmveth_poll(struct napi_struct *napi, int budget) restart_poll: do { - struct sk_buff *skb; - if (!ibmveth_rxq_pending_buffer(adapter)) break; @@ -1014,20 +1017,34 @@ static int ibmveth_poll(struct napi_struct *napi, int budget) ibmveth_debug_printk("recycling invalid buffer\n"); ibmveth_rxq_recycle_buffer(adapter); } else { + struct sk_buff *skb, *new_skb; int length = ibmveth_rxq_frame_length(adapter); int offset = ibmveth_rxq_frame_offset(adapter); int csum_good = ibmveth_rxq_csum_good(adapter); skb = ibmveth_rxq_get_buffer(adapter); - if (csum_good) - skb->ip_summed = CHECKSUM_UNNECESSARY; - ibmveth_rxq_harvest_buffer(adapter); + new_skb = NULL; + if (length < rx_copybreak) + new_skb = netdev_alloc_skb(netdev, length); + + if (new_skb) { + skb_copy_to_linear_data(new_skb, + skb->data + offset, + length); + skb = new_skb; + ibmveth_rxq_recycle_buffer(adapter); + } else { + ibmveth_rxq_harvest_buffer(adapter); + skb_reserve(skb, offset); + } - skb_reserve(skb, offset); skb_put(skb, length); skb->protocol = eth_type_trans(skb, netdev); + if (csum_good) + skb->ip_summed = CHECKSUM_UNNECESSARY; + netif_receive_skb(skb); /* send it up */ netdev->stats.rx_packets++; -- 2.30.2