From 6febfca98f25c7ee5c3ff7fc85e048bf82230ad5 Mon Sep 17 00:00:00 2001 From: Changli Gao Date: Fri, 3 Sep 2010 23:12:37 +0000 Subject: [PATCH] net: rps: add the shortcut for one rps_cpus When there is only one rps_cpus, skb_get_rxhash() can be eliminated. Signed-off-by: Changli Gao Signed-off-by: David S. Miller --- net/core/dev.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index efd318db11ab..cdbbea39c549 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2343,7 +2343,7 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, struct rps_dev_flow **rflowp) { struct netdev_rx_queue *rxqueue; - struct rps_map *map; + struct rps_map *map = NULL; struct rps_dev_flow_table *flow_table; struct rps_sock_flow_table *sock_flow_table; int cpu = -1; @@ -2361,8 +2361,17 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, } else rxqueue = dev->_rx; - if (!rxqueue->rps_map && !rxqueue->rps_flow_table) + if (rxqueue->rps_map) { + map = rcu_dereference(rxqueue->rps_map); + if (map && map->len == 1) { + tcpu = map->cpus[0]; + if (cpu_online(tcpu)) + cpu = tcpu; + goto done; + } + } else if (!rxqueue->rps_flow_table) { goto done; + } skb_reset_network_header(skb); if (!skb_get_rxhash(skb)) @@ -2407,7 +2416,6 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, } } - map = rcu_dereference(rxqueue->rps_map); if (map) { tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32]; -- 2.39.5