[PATCH] af-packet: Use existing netdev reference for bound sockets.
From: <hidden>
Date: 2011-05-25 23:15:37
From: Ben Greear <redacted> This saves a network device lookup on each packet transmitted, for sockets that are bound to a network device. Signed-off-by: Ben Greear <redacted> --- :100644 100644 4005b24... 658edd1... M net/packet/af_packet.c net/packet/af_packet.c | 26 +++++++++++++++++++------- 1 files changed, 19 insertions(+), 7 deletions(-)
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 4005b24..658edd1 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c@@ -987,8 +987,9 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) { struct sk_buff *skb; - struct net_device *dev; + struct net_device *dev = NULL; __be16 proto; + bool need_rls_dev = false; int ifindex, err, reserve = 0; void *ph; struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
@@ -1002,6 +1003,7 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) err = -EBUSY; if (saddr == NULL) { ifindex = po->ifindex; + dev = po->prot_hook.dev; proto = po->num; addr = NULL; } else {
@@ -1017,7 +1019,10 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) addr = saddr->sll_addr; } - dev = dev_get_by_index(sock_net(&po->sk), ifindex); + if (!dev) { + dev = dev_get_by_index(sock_net(&po->sk), ifindex); + need_rls_dev = true; + } err = -ENXIO; if (unlikely(dev == NULL)) goto out;
@@ -1103,7 +1108,8 @@ out_status: __packet_set_status(po, ph, status); kfree_skb(skb); out_put: - dev_put(dev); + if (need_rls_dev) + dev_put(dev); out: mutex_unlock(&po->pg_vec_lock); return err;
@@ -1139,8 +1145,9 @@ static int packet_snd(struct socket *sock, struct sock *sk = sock->sk; struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name; struct sk_buff *skb; - struct net_device *dev; + struct net_device *dev = NULL; __be16 proto; + bool need_rls_dev = false; unsigned char *addr; int ifindex, err, reserve = 0; struct virtio_net_hdr vnet_hdr = { 0 };
@@ -1161,6 +1168,7 @@ static int packet_snd(struct socket *sock, if (saddr == NULL) { ifindex = po->ifindex; + dev = po->prot_hook.dev; proto = po->num; addr = NULL; } else {
@@ -1174,8 +1182,11 @@ static int packet_snd(struct socket *sock, addr = saddr->sll_addr; } + if (!dev) { + dev = dev_get_by_index(sock_net(sk), ifindex); + need_rls_dev = true; + } - dev = dev_get_by_index(sock_net(sk), ifindex); err = -ENXIO; if (dev == NULL) goto out_unlock;
@@ -1315,14 +1326,15 @@ static int packet_snd(struct socket *sock, if (err > 0 && (err = net_xmit_errno(err)) != 0) goto out_unlock; - dev_put(dev); + if (need_rls_dev) + dev_put(dev); return len; out_free: kfree_skb(skb); out_unlock: - if (dev) + if (dev && need_rls_dev) dev_put(dev); out: return err;
--
1.7.3.4