From mboxrd@z Thu Jan 1 00:00:00 1970 From: greearb@candelatech.com Subject: [PATCH 2/2 v3] af-packet: Use existing netdev reference for bound sockets. Date: Wed, 1 Jun 2011 10:18:53 -0700 Message-ID: <1306948733-22441-2-git-send-email-greearb@candelatech.com> References: <1306948733-22441-1-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]:35506 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758056Ab1FARTQ (ORCPT ); Wed, 1 Jun 2011 13:19:16 -0400 In-Reply-To: <1306948733-22441-1-git-send-email-greearb@candelatech.com> 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 --- v3: No changes since last time, but previous patch to hold prot_hook.dev should fix locking problems with this patch. :100644 100644 614d659... c1c5f33... M net/packet/af_packet.c net/packet/af_packet.c | 27 +++++++++++++++------------ 1 files changed, 15 insertions(+), 12 deletions(-) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 614d659..c1c5f33 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -994,7 +994,8 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) struct sk_buff *skb; struct net_device *dev; __be16 proto; - int ifindex, err, reserve = 0; + bool need_rls_dev = false; + int err, reserve = 0; void *ph; struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name; int tp_len, size_max; @@ -1006,7 +1007,7 @@ 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 { @@ -1017,12 +1018,12 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) + offsetof(struct sockaddr_ll, sll_addr))) goto out; - ifindex = saddr->sll_ifindex; proto = saddr->sll_protocol; addr = saddr->sll_addr; + dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex); + need_rls_dev = true; } - dev = dev_get_by_index(sock_net(&po->sk), ifindex); err = -ENXIO; if (unlikely(dev == NULL)) goto out; @@ -1108,7 +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; @@ -1146,8 +1148,9 @@ static int packet_snd(struct socket *sock, struct sk_buff *skb; struct net_device *dev; __be16 proto; + bool need_rls_dev = false; unsigned char *addr; - int ifindex, err, reserve = 0; + int err, reserve = 0; struct virtio_net_hdr vnet_hdr = { 0 }; int offset = 0; int vnet_hdr_len; @@ -1165,7 +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 { @@ -1174,13 +1177,12 @@ static int packet_snd(struct socket *sock, goto out; if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr))) goto out; - ifindex = saddr->sll_ifindex; proto = saddr->sll_protocol; addr = saddr->sll_addr; + dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex); + need_rls_dev = true; } - - dev = dev_get_by_index(sock_net(sk), ifindex); err = -ENXIO; if (dev == NULL) goto out_unlock; @@ -1320,14 +1322,15 @@ 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