From mboxrd@z Thu Jan 1 00:00:00 1970 From: greearb@candelatech.com Subject: [RFC] af-packet: Save reference to bound network device. Date: Wed, 25 May 2011 14:56:42 -0700 Message-ID: <1306360602-9672-1-git-send-email-greearb@candelatech.com> Cc: Ben Greear To: netdev@vger.kernel.org Return-path: Received: from mail.candelatech.com ([208.74.158.172]:46345 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755561Ab1EYV4s (ORCPT ); Wed, 25 May 2011 17:56:48 -0400 Sender: netdev-owner@vger.kernel.org List-ID: From: Ben Greear This saves a network device lookup on each packet transmitted, for sockets that are bound to a network device. Signed-off-by: Ben Greear --- :100644 100644 4005b24... ba16759... M net/packet/af_packet.c net/packet/af_packet.c | 48 +++++++++++++++++++++++++++++++++++------------- 1 files changed, 35 insertions(+), 13 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 4005b24..ba16759 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -201,8 +201,9 @@ struct packet_sock { auxdata:1, origdev:1, has_vnet_hdr:1; - int ifindex; /* bound device */ + int ifindex; /* bound device id */ __be16 num; + struct net_device *bound_dev; /* bound device */ struct packet_mclist *mclist; atomic_t mapped; enum tpacket_versions tp_version; @@ -987,8 +988,9 @@ 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 +1004,7 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) err = -EBUSY; if (saddr == NULL) { ifindex = po->ifindex; + dev = po->bound_dev; proto = po->num; addr = NULL; } else { @@ -1017,7 +1020,10 @@ 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 +1109,8 @@ 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 +1146,9 @@ 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 +1169,7 @@ static int packet_snd(struct socket *sock, if (saddr == NULL) { ifindex = po->ifindex; + dev = po->bound_dev; proto = po->num; addr = NULL; } else { @@ -1174,8 +1183,11 @@ 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 +1327,15 @@ 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; @@ -1372,6 +1385,12 @@ static int packet_release(struct socket *sock) __dev_remove_pack(&po->prot_hook); __sock_put(sk); } + + if (po->bound_dev) { + dev_put(po->bound_dev); + po->bound_dev = NULL; + } + spin_unlock(&po->bind_lock); packet_flush_mclist(sk); @@ -1428,6 +1447,9 @@ static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protoc po->prot_hook.dev = dev; po->ifindex = dev ? dev->ifindex : 0; + if (po->bound_dev) + dev_put(po->bound_dev); + po->bound_dev = dev; if (protocol == 0) goto out_unlock; @@ -1469,10 +1491,8 @@ static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, strlcpy(name, uaddr->sa_data, sizeof(name)); dev = dev_get_by_name(sock_net(sk), name); - if (dev) { + if (dev) err = packet_do_bind(sk, dev, pkt_sk(sk)->num); - dev_put(dev); - } return err; } @@ -1500,8 +1520,6 @@ static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len goto out; } err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num); - if (dev) - dev_put(dev); out: return err; @@ -2266,6 +2284,10 @@ static int packet_notifier(struct notifier_block *this, unsigned long msg, void } if (msg == NETDEV_UNREGISTER) { po->ifindex = -1; + if (po->bound_dev) { + dev_put(po->bound_dev); + po->bound_dev = NULL; + } po->prot_hook.dev = NULL; } spin_unlock(&po->bind_lock); -- 1.7.3.4