openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

sky2: no recycling 

Recycling turns out to be a bad idea!  For most use cases, the
packet can not be reused: TCP packets are cloned. Even for the ideal
case of forwarding, it hurts performance because of CPU ping/pong.
On a multi-core system forwarding of 64 byte packets is worse
much worse: recycling = 24% forwarded vs no recycling = 42% forwarded

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stephen Hemminger 2009-08-18 15:17:10 +00:00 committed by David S. Miller
parent 6b84dacadb
commit 724b694225
2 changed files with 3 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
drivers/net/sky2.c
View File

@ -1177,7 +1177,6 @@ static void sky2_rx_clean(struct sky2_port *sky2)
re->skb = NULL;
}
}
skb_queue_purge(&sky2->rx_recycle);
}
/* Basic MII support */
@ -1269,10 +1268,8 @@ static struct sk_buff *sky2_rx_alloc(struct sky2_port *sky2)
struct sk_buff *skb;
int i;
skb = __skb_dequeue(&sky2->rx_recycle);
if (!skb)
skb = netdev_alloc_skb(sky2->netdev, sky2->rx_data_size
+ sky2_rx_pad(sky2->hw));
skb = netdev_alloc_skb(sky2->netdev,
sky2->rx_data_size + sky2_rx_pad(sky2->hw));
if (!skb)
goto nomem;
@ -1364,8 +1361,6 @@ static int sky2_rx_start(struct sky2_port *sky2)
sky2->rx_data_size = size;
skb_queue_head_init(&sky2->rx_recycle);
/* Fill Rx ring */
for (i = 0; i < sky2->rx_pending; i++) {
re = sky2->rx_ring + i;
@ -1776,12 +1771,7 @@ static void sky2_tx_complete(struct sky2_port *sky2, u16 done)
dev->stats.tx_packets++;
dev->stats.tx_bytes += skb->len;
if (skb_queue_len(&sky2->rx_recycle) < sky2->rx_pending
&& skb_recycle_check(skb, sky2->rx_data_size
+ sky2_rx_pad(sky2->hw)))
__skb_queue_head(&sky2->rx_recycle, skb);
else
dev_kfree_skb_any(skb);
dev_kfree_skb_any(skb);
sky2->tx_next = RING_NEXT(idx, sky2->tx_ring_size);
}

1
drivers/net/sky2.h
View File

@ -2032,7 +2032,6 @@ struct sky2_port {
u16 rx_pending;
u16 rx_data_size;
u16 rx_nfrags;
struct sk_buff_head rx_recycle;
#ifdef SKY2_VLAN_TAG_USED
u16 rx_tag;