commit d5a9e24afb4ab38110ebb777588ea0bd0eacbd0a Author: David S. Miller Date: Tue Jan 27 16:22:11 2009 -0800 net: Allow RX queue selection to seed TX queue hashing. The idea is that drivers which implement multiqueue RX pre-seed the SKB by recording the RX queue selected by the hardware. If such a seed is found on TX, we'll use that to select the outgoing TX queue. This helps get more consistent load balancing on router and firewall loads. Signed-off-by: David S. Miller Index: hurd-debian/libdde-linux26/contrib/include/linux/skbuff.h =================================================================== --- hurd-debian.orig/libdde-linux26/contrib/include/linux/skbuff.h 2012-04-16 00:34:56.000000000 +0000 +++ hurd-debian/libdde-linux26/contrib/include/linux/skbuff.h 2012-04-16 00:35:11.000000000 +0000 @@ -1903,6 +1903,21 @@ to->queue_mapping = from->queue_mapping; } +static inline void skb_record_rx_queue(struct sk_buff *skb, u16 rx_queue) +{ + skb->queue_mapping = rx_queue + 1; +} + +static inline u16 skb_get_rx_queue(struct sk_buff *skb) +{ + return skb->queue_mapping - 1; +} + +static inline bool skb_rx_queue_recorded(struct sk_buff *skb) +{ + return (skb->queue_mapping != 0); +} + #ifdef CONFIG_XFRM static inline struct sec_path *skb_sec_path(struct sk_buff *skb) { Index: hurd-debian/libdde-linux26/lib/src/net/core/dev.c =================================================================== --- hurd-debian.orig/libdde-linux26/lib/src/net/core/dev.c 2012-04-16 00:34:51.000000000 +0000 +++ hurd-debian/libdde-linux26/lib/src/net/core/dev.c 2012-04-16 00:35:11.000000000 +0000 @@ -1731,6 +1731,13 @@ simple_tx_hashrnd_initialized = 1; } + if (skb_rx_queue_recorded(skb)) { + u32 val = skb_get_rx_queue(skb); + + hash = jhash_1word(val, simple_tx_hashrnd); + goto out; + } + switch (skb->protocol) { case htons(ETH_P_IP): if (!(ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET))) @@ -1768,6 +1775,7 @@ hash = jhash_3words(addr1, addr2, ports, simple_tx_hashrnd); +out: return (u16) (((u64) hash * dev->real_num_tx_queues) >> 32); }