diff mbox

[v4,net-next,2/4] tcp: add TCP support for low latency receive poll.

Message ID 20130521142659.18498.1984.stgit@ladj378.jer.intel.com
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Eliezer Tamir May 21, 2013, 2:27 p.m. UTC 
adds busy-poll support for TCP.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
---

 net/ipv4/tcp.c       |    9 +++++++++
 net/ipv4/tcp_input.c |    4 ++++
 2 files changed, 13 insertions(+), 0 deletions(-)


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Comments

Ben Hutchings May 21, 2013, 5:30 p.m. UTC | #1 
On Tue, 2013-05-21 at 17:27 +0300, Eliezer Tamir wrote:
> adds busy-poll support for TCP.
> 
> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
> Tested-by: Willem de Bruijn <willemb@google.com>
> Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
> ---
> 
>  net/ipv4/tcp.c       |    9 +++++++++
>  net/ipv4/tcp_input.c |    4 ++++
>  2 files changed, 13 insertions(+), 0 deletions(-)
> 
> diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
> index dcb116d..b9cc512 100644
> --- a/net/ipv4/tcp.c
> +++ b/net/ipv4/tcp.c
[...]
> @@ -1551,6 +1553,12 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
>  	struct sk_buff *skb;
>  	u32 urg_hole = 0;
>  
> +#ifdef CONFIG_INET_LL_RX_POLL
> +	if (sk_valid_ll(sk) && skb_queue_empty(&sk->sk_receive_queue)
> +	    && (sk->sk_state == TCP_ESTABLISHED))
> +		sk_poll_ll(sk, nonblock);
> +#endif
[...]

I don't think the #ifdef is needed; this should compile down to nothing
if the config option is disabled.

Ben.
diff mbox

Patch

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index dcb116d..b9cc512 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -279,6 +279,7 @@ 
 
 #include <asm/uaccess.h>
 #include <asm/ioctls.h>
+#include <net/ll_poll.h>
 
 int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT;
 
@@ -1504,6 +1505,7 @@  int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
 			if (offset + 1 != skb->len)
 				continue;
 		}
+		sk_mark_ll(sk, skb);
 		if (tcp_hdr(skb)->fin) {
 			sk_eat_skb(sk, skb, false);
 			++seq;
@@ -1551,6 +1553,12 @@  int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 	struct sk_buff *skb;
 	u32 urg_hole = 0;
 
+#ifdef CONFIG_INET_LL_RX_POLL
+	if (sk_valid_ll(sk) && skb_queue_empty(&sk->sk_receive_queue)
+	    && (sk->sk_state == TCP_ESTABLISHED))
+		sk_poll_ll(sk, nonblock);
+#endif
+
 	lock_sock(sk);
 
 	err = -ENOTCONN;
@@ -1855,6 +1863,7 @@  do_prequeue:
 					break;
 				}
 			}
+			sk_mark_ll(sk, skb);
 		}
 
 		*seq += used;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index b358e8c..f3f293b 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -74,6 +74,7 @@ 
 #include <linux/ipsec.h>
 #include <asm/unaligned.h>
 #include <net/netdma.h>
+#include <net/ll_poll.h>
 
 int sysctl_tcp_timestamps __read_mostly = 1;
 int sysctl_tcp_window_scaling __read_mostly = 1;
@@ -4329,6 +4330,7 @@  static void tcp_data_queue(struct sock *sk, struct sk_buff *skb)
 				tp->copied_seq += chunk;
 				eaten = (chunk == skb->len);
 				tcp_rcv_space_adjust(sk);
+				sk_mark_ll(sk, skb);
 			}
 			local_bh_disable();
 		}
@@ -4896,6 +4898,7 @@  static int tcp_copy_to_iovec(struct sock *sk, struct sk_buff *skb, int hlen)
 		tp->ucopy.len -= chunk;
 		tp->copied_seq += chunk;
 		tcp_rcv_space_adjust(sk);
+		sk_mark_ll(sk, skb);
 	}
 
 	local_bh_disable();
@@ -4955,6 +4958,7 @@  static bool tcp_dma_try_early_copy(struct sock *sk, struct sk_buff *skb,
 		tp->ucopy.len -= chunk;
 		tp->copied_seq += chunk;
 		tcp_rcv_space_adjust(sk);
+		sk_mark_ll(sk, skb);
 
 		if ((tp->ucopy.len == 0) ||
 		    (tcp_flag_word(tcp_hdr(skb)) & TCP_FLAG_PSH) ||