icmp: No need to call sk_write_space()

We can make icmp messages tx completion callback a litle bit faster.

Setting SOCK_USE_WRITE_QUEUE sk flag tells sock_wfree() to
not call sk_write_space() on a socket we know no thread is posssibly
waiting for write space. (on per cpu kernel internal icmp sockets only)

This avoids the sock_def_write_space() call and
read_lock(&sk->sk_callback_lock)/read_unlock(&sk->sk_callback_lock) calls
as well.

We avoid three atomic ops.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2009-09-24 12:16:51 +00:00 committed by David S. Miller
parent a9828ec6bc
commit b3a5b6cc7c
1 changed files with 4 additions and 0 deletions

View File

@ -1165,6 +1165,10 @@ static int __net_init icmp_sk_init(struct net *net)
sk->sk_sndbuf =
(2 * ((64 * 1024) + sizeof(struct sk_buff)));
/*
* Speedup sock_wfree()
*/
sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
inet_sk(sk)->pmtudisc = IP_PMTUDISC_DONT;
}