netdev - [PATCH v2 net-next 1/2] tcp: move sk_mark_napi

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 11 Nov 2014 05:54:27 -0800
From:	Eric Dumazet <edumazet@...gle.com>
To:	"David S. Miller" <davem@...emloft.net>
Cc:	netdev@...r.kernel.org, Neal Cardwell <ncardwell@...gle.com>,
	Willem de Bruijn <willemb@...gle.com>,
	Ying Cai <ycai@...gle.com>, Eric Dumazet <edumazet@...gle.com>
Subject: [PATCH v2 net-next 1/2] tcp: move sk_mark_napi_id() at the right place

sk_mark_napi_id() is used to record for a flow napi id of incoming
packets for busypoll sake.
We should do this only on established flows, not on listeners.

This was 'working' by virtue of the socket cloning, but doing
this on SYN packets in unecessary cache line dirtying.

Even if we move sk_napi_id in the same cache line than sk_lock,
we are working to make SYN processing lockless, so it is desirable
to set sk_napi_id only for established flows.

Signed-off-by: Eric Dumazet <edumazet@...gle.com>
---
 net/ipv4/tcp_ipv4.c | 3 ++-
 net/ipv6/tcp_ipv6.c | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 9c7d7621466b..8893598a4124 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1429,6 +1429,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 		struct dst_entry *dst = sk->sk_rx_dst;
 
 		sock_rps_save_rxhash(sk, skb);
+		sk_mark_napi_id(sk, skb);
 		if (dst) {
 			if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif ||
 			    dst->ops->check(dst, 0) == NULL) {
@@ -1450,6 +1451,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 
 		if (nsk != sk) {
 			sock_rps_save_rxhash(nsk, skb);
+			sk_mark_napi_id(sk, skb);
 			if (tcp_child_process(sk, nsk, skb)) {
 				rsk = nsk;
 				goto reset;
@@ -1661,7 +1663,6 @@ process:
 	if (sk_filter(sk, skb))
 		goto discard_and_relse;
 
-	sk_mark_napi_id(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 ace29b60813c..fd8e50b380e7 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1293,6 +1293,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
 		struct dst_entry *dst = sk->sk_rx_dst;
 
 		sock_rps_save_rxhash(sk, skb);
+		sk_mark_napi_id(sk, skb);
 		if (dst) {
 			if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif ||
 			    dst->ops->check(dst, np->rx_dst_cookie) == NULL) {
@@ -1322,6 +1323,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
 		 */
 		if (nsk != sk) {
 			sock_rps_save_rxhash(nsk, skb);
+			sk_mark_napi_id(sk, skb);
 			if (tcp_child_process(sk, nsk, skb))
 				goto reset;
 			if (opt_skb)
@@ -1454,7 +1456,6 @@ process:
 	if (sk_filter(sk, skb))
 		goto discard_and_relse;
 
-	sk_mark_napi_id(sk, skb);
 	skb->dev = NULL;
 
 	bh_lock_sock_nested(sk);
-- 
2.1.0.rc2.206.gedb03e5

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