From d30e383bb856f614ddb5bbbb5a7d3f86240e41ec Mon Sep 17 00:00:00 2001 From: Eliezer Tamir Date: Mon, 10 Jun 2013 11:40:10 +0300 Subject: [PATCH] tcp: add low latency socket poll support. Adds low latency socket poll support for TCP. In tcp_v[46]_rcv() add a call to sk_mark_ll() to copy the napi_id from the skb to the sk. In tcp_recvmsg(), when there is no data in the socket we busy-poll. This is a good example of how to add busy-poll support to more protocols. Signed-off-by: Alexander Duyck Signed-off-by: Jesse Brandeburg Signed-off-by: Eliezer Tamir Acked-by: Eric Dumazet Tested-by: Willem de Bruijn Signed-off-by: David S. Miller --- net/ipv4/tcp.c | 5 +++++ net/ipv4/tcp_ipv4.c | 2 ++ net/ipv6/tcp_ipv6.c | 2 ++ 3 files changed, 9 insertions(+) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index bc4246940f6c..46ed9afd1f5e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -279,6 +279,7 @@ #include #include +#include int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT; @@ -1553,6 +1554,10 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, struct sk_buff *skb; u32 urg_hole = 0; + if (sk_valid_ll(sk) && skb_queue_empty(&sk->sk_receive_queue) + && (sk->sk_state == TCP_ESTABLISHED)) + sk_poll_ll(sk, nonblock); + lock_sock(sk); err = -ENOTCONN; diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 289039b4d8de..1063bb83e342 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -75,6 +75,7 @@ #include #include #include +#include #include #include @@ -1993,6 +1994,7 @@ process: if (sk_filter(sk, skb)) goto discard_and_relse; + sk_mark_ll(sk, skb); skb->dev = NULL; bh_lock_sock_nested(sk); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 0a17ed9eaf39..5cffa5c3e6b8 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -63,6 +63,7 @@ #include #include #include +#include #include @@ -1498,6 +1499,7 @@ process: if (sk_filter(sk, skb)) goto discard_and_relse; + sk_mark_ll(sk, skb); skb->dev = NULL; bh_lock_sock_nested(sk); -- 2.20.1