RDS/TCP: Wait to wake thread when write space available

Instead of waking the send thread whenever any send space is available,
wait until it is at least half empty. This is modeled on how
sock_def_write_space() does it, and may help to minimize context
switches.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Andy Grover 2010-03-11 13:49:58 +00:00 committed by David S. Miller
parent b075cfdb66
commit 8e82376e5f

View file

@ -240,7 +240,9 @@ void rds_tcp_write_space(struct sock *sk)
tc->t_last_seen_una = rds_tcp_snd_una(tc);
rds_send_drop_acked(conn, rds_tcp_snd_una(tc), rds_tcp_is_acked);
queue_delayed_work(rds_wq, &conn->c_send_w, 0);
if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf)
queue_delayed_work(rds_wq, &conn->c_send_w, 0);
out:
read_unlock(&sk->sk_callback_lock);