From 7866a621043fbaca3d7389e9b9f69dd1a2e5a855 Mon Sep 17 00:00:00 2001 From: Salam Noureddine Date: Tue, 27 Jan 2015 11:35:48 -0800 Subject: [PATCH] dev: add per net_device packet type chains When many pf_packet listeners are created on a lot of interfaces the current implementation using global packet type lists scales poorly. This patch adds per net_device packet type lists to fix this problem. The patch was originally written by Eric Biederman for linux-2.6.29. Tested on linux-3.16. Signed-off-by: "Eric W. Biederman" Signed-off-by: Salam Noureddine Signed-off-by: David S. Miller --- include/linux/netdevice.h | 2 + net/core/dev.c | 132 ++++++++++++++++++++++++-------------- 2 files changed, 86 insertions(+), 48 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 642d426a668f..3d37c6eb1732 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1514,6 +1514,8 @@ struct net_device { struct list_head napi_list; struct list_head unreg_list; struct list_head close_list; + struct list_head ptype_all; + struct list_head ptype_specific; struct { struct list_head upper; diff --git a/net/core/dev.c b/net/core/dev.c index 7f028d441e98..1d564d68e31a 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -371,9 +371,10 @@ static inline void netdev_set_addr_lockdep_class(struct net_device *dev) static inline struct list_head *ptype_head(const struct packet_type *pt) { if (pt->type == htons(ETH_P_ALL)) - return &ptype_all; + return pt->dev ? &pt->dev->ptype_all : &ptype_all; else - return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; + return pt->dev ? &pt->dev->ptype_specific : + &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; } /** @@ -1734,6 +1735,23 @@ static inline int deliver_skb(struct sk_buff *skb, return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); } +static inline void deliver_ptype_list_skb(struct sk_buff *skb, + struct packet_type **pt, + struct net_device *dev, __be16 type, + struct list_head *ptype_list) +{ + struct packet_type *ptype, *pt_prev = *pt; + + list_for_each_entry_rcu(ptype, ptype_list, list) { + if (ptype->type != type) + continue; + if (pt_prev) + deliver_skb(skb, pt_prev, dev); + pt_prev = ptype; + } + *pt = pt_prev; +} + static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) { if (!ptype->af_packet_priv || !skb->sk) @@ -1757,45 +1775,54 @@ static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) struct packet_type *ptype; struct sk_buff *skb2 = NULL; struct packet_type *pt_prev = NULL; + struct list_head *ptype_list = &ptype_all; rcu_read_lock(); - list_for_each_entry_rcu(ptype, &ptype_all, list) { +again: + list_for_each_entry_rcu(ptype, ptype_list, list) { /* Never send packets back to the socket * they originated from - MvS (miquels@drinkel.ow.org) */ - if ((ptype->dev == dev || !ptype->dev) && - (!skb_loop_sk(ptype, skb))) { - if (pt_prev) { - deliver_skb(skb2, pt_prev, skb->dev); - pt_prev = ptype; - continue; - } + if (skb_loop_sk(ptype, skb)) + continue; - skb2 = skb_clone(skb, GFP_ATOMIC); - if (!skb2) - break; + if (pt_prev) { + deliver_skb(skb2, pt_prev, skb->dev); + pt_prev = ptype; + continue; + } - net_timestamp_set(skb2); + /* need to clone skb, done only once */ + skb2 = skb_clone(skb, GFP_ATOMIC); + if (!skb2) + goto out_unlock; - /* skb->nh should be correctly - set by sender, so that the second statement is - just protection against buggy protocols. - */ - skb_reset_mac_header(skb2); - - if (skb_network_header(skb2) < skb2->data || - skb_network_header(skb2) > skb_tail_pointer(skb2)) { - net_crit_ratelimited("protocol %04x is buggy, dev %s\n", - ntohs(skb2->protocol), - dev->name); - skb_reset_network_header(skb2); - } + net_timestamp_set(skb2); - skb2->transport_header = skb2->network_header; - skb2->pkt_type = PACKET_OUTGOING; - pt_prev = ptype; + /* skb->nh should be correctly + * set by sender, so that the second statement is + * just protection against buggy protocols. + */ + skb_reset_mac_header(skb2); + + if (skb_network_header(skb2) < skb2->data || + skb_network_header(skb2) > skb_tail_pointer(skb2)) { + net_crit_ratelimited("protocol %04x is buggy, dev %s\n", + ntohs(skb2->protocol), + dev->name); + skb_reset_network_header(skb2); } + + skb2->transport_header = skb2->network_header; + skb2->pkt_type = PACKET_OUTGOING; + pt_prev = ptype; + } + + if (ptype_list == &ptype_all) { + ptype_list = &dev->ptype_all; + goto again; } +out_unlock: if (pt_prev) pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); rcu_read_unlock(); @@ -2617,7 +2644,7 @@ static int xmit_one(struct sk_buff *skb, struct net_device *dev, unsigned int len; int rc; - if (!list_empty(&ptype_all)) + if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all)) dev_queue_xmit_nit(skb, dev); len = skb->len; @@ -3615,7 +3642,6 @@ static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc) struct packet_type *ptype, *pt_prev; rx_handler_func_t *rx_handler; struct net_device *orig_dev; - struct net_device *null_or_dev; bool deliver_exact = false; int ret = NET_RX_DROP; __be16 type; @@ -3658,11 +3684,15 @@ another_round: goto skip_taps; list_for_each_entry_rcu(ptype, &ptype_all, list) { - if (!ptype->dev || ptype->dev == skb->dev) { - if (pt_prev) - ret = deliver_skb(skb, pt_prev, orig_dev); - pt_prev = ptype; - } + if (pt_prev) + ret = deliver_skb(skb, pt_prev, orig_dev); + pt_prev = ptype; + } + + list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { + if (pt_prev) + ret = deliver_skb(skb, pt_prev, orig_dev); + pt_prev = ptype; } skip_taps: @@ -3718,19 +3748,21 @@ ncls: skb->vlan_tci = 0; } + type = skb->protocol; + /* deliver only exact match when indicated */ - null_or_dev = deliver_exact ? skb->dev : NULL; + if (likely(!deliver_exact)) { + deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, + &ptype_base[ntohs(type) & + PTYPE_HASH_MASK]); + } - type = skb->protocol; - list_for_each_entry_rcu(ptype, - &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) { - if (ptype->type == type && - (ptype->dev == null_or_dev || ptype->dev == skb->dev || - ptype->dev == orig_dev)) { - if (pt_prev) - ret = deliver_skb(skb, pt_prev, orig_dev); - pt_prev = ptype; - } + deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, + &orig_dev->ptype_specific); + + if (unlikely(skb->dev != orig_dev)) { + deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, + &skb->dev->ptype_specific); } if (pt_prev) { @@ -6579,6 +6611,8 @@ void netdev_run_todo(void) /* paranoia */ BUG_ON(netdev_refcnt_read(dev)); + BUG_ON(!list_empty(&dev->ptype_all)); + BUG_ON(!list_empty(&dev->ptype_specific)); WARN_ON(rcu_access_pointer(dev->ip_ptr)); WARN_ON(rcu_access_pointer(dev->ip6_ptr)); WARN_ON(dev->dn_ptr); @@ -6761,6 +6795,8 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, INIT_LIST_HEAD(&dev->adj_list.lower); INIT_LIST_HEAD(&dev->all_adj_list.upper); INIT_LIST_HEAD(&dev->all_adj_list.lower); + INIT_LIST_HEAD(&dev->ptype_all); + INIT_LIST_HEAD(&dev->ptype_specific); dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; setup(dev); -- 2.20.1