diff options
| author | Krishna Kumar <krkumar2@in.ibm.com> | 2009-02-19 02:55:02 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-02-19 02:55:02 +0100 |
| commit | e88721f87d8caa679e62d6004a9a5661f1ac7b0e (patch) | |
| tree | 4e5ad54f7445631ac2ec5750dbe245e6c26a140c /net/core | |
| parent | niu: improve ethtool support for gigabit copper cards (diff) | |
| download | linux-e88721f87d8caa679e62d6004a9a5661f1ac7b0e.tar.xz linux-e88721f87d8caa679e62d6004a9a5661f1ac7b0e.zip | |
net: Optimize skb_tx_hash() by eliminating a comparison
Optimize skb_tx_hash() by eliminating a comparison that executes for
every packet. skb_tx_hashrnd initialization is moved to a later part of
the startup sequence, namely after the "random" driver is initialized.
Rebooted the system three times and verified that the code generates
different random numbers each time.
Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/dev.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index d393fc997cd9..5493394118fb 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1745,17 +1745,11 @@ out_kfree_skb: } static u32 skb_tx_hashrnd; -static int skb_tx_hashrnd_initialized = 0; static u16 skb_tx_hash(struct net_device *dev, struct sk_buff *skb) { u32 hash; - if (unlikely(!skb_tx_hashrnd_initialized)) { - get_random_bytes(&skb_tx_hashrnd, 4); - skb_tx_hashrnd_initialized = 1; - } - if (skb_rx_queue_recorded(skb)) { hash = skb_get_rx_queue(skb); } else if (skb->sk && skb->sk->sk_hash) { @@ -5291,6 +5285,14 @@ out: subsys_initcall(net_dev_init); +static int __init initialize_hashrnd(void) +{ + get_random_bytes(&skb_tx_hashrnd, sizeof(skb_tx_hashrnd)); + return 0; +} + +late_initcall_sync(initialize_hashrnd); + EXPORT_SYMBOL(__dev_get_by_index); EXPORT_SYMBOL(__dev_get_by_name); EXPORT_SYMBOL(__dev_remove_pack); |