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| author | David S. Miller <davem@davemloft.net> | 2009-01-28 01:22:11 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-01-28 01:22:11 +0100 |
| commit | d5a9e24afb4ab38110ebb777588ea0bd0eacbd0a (patch) | |
| tree | 819b2f875a9a1835aa92e051460ddcfe53e9e00f | |
| parent | iw_cxgb3: handle chip reset notifications (diff) | |
| download | linux-d5a9e24afb4ab38110ebb777588ea0bd0eacbd0a.tar.xz linux-d5a9e24afb4ab38110ebb777588ea0bd0eacbd0a.zip | |
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 <davem@davemloft.net>
| -rw-r--r-- | include/linux/skbuff.h | 15 | ||||
| -rw-r--r-- | net/core/dev.c | 8 |
2 files changed, 23 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index cf2cb50f77d1..a2c2378a9c58 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1904,6 +1904,21 @@ static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_bu 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) { diff --git a/net/core/dev.c b/net/core/dev.c index 5379b0c1190a..b21ad0b47aae 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1722,6 +1722,13 @@ static u16 simple_tx_hash(struct net_device *dev, struct sk_buff *skb) 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))) @@ -1759,6 +1766,7 @@ static u16 simple_tx_hash(struct net_device *dev, struct sk_buff *skb) hash = jhash_3words(addr1, addr2, ports, simple_tx_hashrnd); +out: return (u16) (((u64) hash * dev->real_num_tx_queues) >> 32); } |