From 47934e06b65637c88a762d9c98329ae6e3238888 Mon Sep 17 00:00:00 2001 From: Congyu Liu Date: Tue, 18 Jan 2022 14:20:13 -0500 Subject: net: fix information leakage in /proc/net/ptype In one net namespace, after creating a packet socket without binding it to a device, users in other net namespaces can observe the new `packet_type` added by this packet socket by reading `/proc/net/ptype` file. This is minor information leakage as packet socket is namespace aware. Add a net pointer in `packet_type` to keep the net namespace of of corresponding packet socket. In `ptype_seq_show`, this net pointer must be checked when it is not NULL. Fixes: 2feb27dbe00c ("[NETNS]: Minor information leak via /proc/net/ptype file.") Signed-off-by: Congyu Liu Signed-off-by: David S. Miller --- include/linux/netdevice.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 3213c7227b59..e490b84732d1 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2548,6 +2548,7 @@ struct packet_type { struct net_device *); bool (*id_match)(struct packet_type *ptype, struct sock *sk); + struct net *af_packet_net; void *af_packet_priv; struct list_head list; }; -- cgit v1.3-14-g43fede From 4c6c11ea0f7b00a1894803efe980dfaf3b074886 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 4 Feb 2022 14:42:37 -0800 Subject: net: refine dev_put()/dev_hold() debugging We are still chasing some syzbot reports where we think a rogue dev_put() is called with no corresponding prior dev_hold(). Unfortunately it eats a reference on dev->dev_refcnt taken by innocent dev_hold_track(), meaning that the refcount saturation splat comes too late to be useful. Make sure that 'not tracked' dev_put() and dev_hold() better use CONFIG_NET_DEV_REFCNT_TRACKER=y debug infrastructure: Prior patch in the series allowed ref_tracker_alloc() and ref_tracker_free() to be called with a NULL @trackerp parameter, and to use a separate refcount only to detect too many put() even in the following case: dev_hold_track(dev, tracker_1, GFP_ATOMIC); dev_hold(dev); dev_put(dev); dev_put(dev); // Should complain loudly here. dev_put_track(dev, tracker_1); // instead of here Add clarification about netdev_tracker_alloc() role. v2: I replaced the dev_put() in linkwatch_do_dev() with __dev_put() because callers called netdev_tracker_free(). Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/netdevice.h | 69 +++++++++++++++++++++++++++++++---------------- net/core/dev.c | 2 +- net/core/link_watch.c | 6 ++--- 3 files changed, 50 insertions(+), 27 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index e490b84732d1..3fb6fb67ed77 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3817,14 +3817,7 @@ extern unsigned int netdev_budget_usecs; /* Called by rtnetlink.c:rtnl_unlock() */ void netdev_run_todo(void); -/** - * dev_put - release reference to device - * @dev: network device - * - * Release reference to device to allow it to be freed. - * Try using dev_put_track() instead. - */ -static inline void dev_put(struct net_device *dev) +static inline void __dev_put(struct net_device *dev) { if (dev) { #ifdef CONFIG_PCPU_DEV_REFCNT @@ -3835,14 +3828,7 @@ static inline void dev_put(struct net_device *dev) } } -/** - * dev_hold - get reference to device - * @dev: network device - * - * Hold reference to device to keep it from being freed. - * Try using dev_hold_track() instead. - */ -static inline void dev_hold(struct net_device *dev) +static inline void __dev_hold(struct net_device *dev) { if (dev) { #ifdef CONFIG_PCPU_DEV_REFCNT @@ -3853,11 +3839,24 @@ static inline void dev_hold(struct net_device *dev) } } +static inline void __netdev_tracker_alloc(struct net_device *dev, + netdevice_tracker *tracker, + gfp_t gfp) +{ +#ifdef CONFIG_NET_DEV_REFCNT_TRACKER + ref_tracker_alloc(&dev->refcnt_tracker, tracker, gfp); +#endif +} + +/* netdev_tracker_alloc() can upgrade a prior untracked reference + * taken by dev_get_by_name()/dev_get_by_index() to a tracked one. + */ static inline void netdev_tracker_alloc(struct net_device *dev, netdevice_tracker *tracker, gfp_t gfp) { #ifdef CONFIG_NET_DEV_REFCNT_TRACKER - ref_tracker_alloc(&dev->refcnt_tracker, tracker, gfp); + refcount_dec(&dev->refcnt_tracker.no_tracker); + __netdev_tracker_alloc(dev, tracker, gfp); #endif } @@ -3873,8 +3872,8 @@ static inline void dev_hold_track(struct net_device *dev, netdevice_tracker *tracker, gfp_t gfp) { if (dev) { - dev_hold(dev); - netdev_tracker_alloc(dev, tracker, gfp); + __dev_hold(dev); + __netdev_tracker_alloc(dev, tracker, gfp); } } @@ -3883,10 +3882,34 @@ static inline void dev_put_track(struct net_device *dev, { if (dev) { netdev_tracker_free(dev, tracker); - dev_put(dev); + __dev_put(dev); } } +/** + * dev_hold - get reference to device + * @dev: network device + * + * Hold reference to device to keep it from being freed. + * Try using dev_hold_track() instead. + */ +static inline void dev_hold(struct net_device *dev) +{ + dev_hold_track(dev, NULL, GFP_ATOMIC); +} + +/** + * dev_put - release reference to device + * @dev: network device + * + * Release reference to device to allow it to be freed. + * Try using dev_put_track() instead. + */ +static inline void dev_put(struct net_device *dev) +{ + dev_put_track(dev, NULL); +} + static inline void dev_replace_track(struct net_device *odev, struct net_device *ndev, netdevice_tracker *tracker, @@ -3895,11 +3918,11 @@ static inline void dev_replace_track(struct net_device *odev, if (odev) netdev_tracker_free(odev, tracker); - dev_hold(ndev); - dev_put(odev); + __dev_hold(ndev); + __dev_put(odev); if (ndev) - netdev_tracker_alloc(ndev, tracker, gfp); + __netdev_tracker_alloc(ndev, tracker, gfp); } /* Carrier loss detection, dial on demand. The functions netif_carrier_on diff --git a/net/core/dev.c b/net/core/dev.c index f79744d99413..1eaa0b88e3ba 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10172,7 +10172,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, dev->pcpu_refcnt = alloc_percpu(int); if (!dev->pcpu_refcnt) goto free_dev; - dev_hold(dev); + __dev_hold(dev); #else refcount_set(&dev->dev_refcnt, 1); #endif diff --git a/net/core/link_watch.c b/net/core/link_watch.c index b0f5344d1185..95098d1a49bd 100644 --- a/net/core/link_watch.c +++ b/net/core/link_watch.c @@ -166,10 +166,10 @@ static void linkwatch_do_dev(struct net_device *dev) netdev_state_change(dev); } - /* Note: our callers are responsible for - * calling netdev_tracker_free(). + /* Note: our callers are responsible for calling netdev_tracker_free(). + * This is the reason we use __dev_put() instead of dev_put(). */ - dev_put(dev); + __dev_put(dev); } static void __linkwatch_run_queue(int urgent_only) -- cgit v1.3-14-g43fede From b2309a71c1f2fc841feb184195b2e46b2e139bf4 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 7 Feb 2022 10:41:07 -0800 Subject: net: add dev->dev_registered_tracker Convert one dev_hold()/dev_put() pair in register_netdevice() and unregister_netdevice_many() to dev_hold_track() and dev_put_track(). This would allow to detect a rogue dev_put() a bit earlier. Signed-off-by: Eric Dumazet Link: https://lore.kernel.org/r/20220207184107.1401096-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski --- include/linux/netdevice.h | 3 +++ net/core/dev.c | 6 ++++-- 2 files changed, 7 insertions(+), 2 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 3fb6fb67ed77..5f6e2c0b0c90 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1948,6 +1948,8 @@ enum netdev_ml_priv_type { * @dev_addr_shadow: Copy of @dev_addr to catch direct writes. * @linkwatch_dev_tracker: refcount tracker used by linkwatch. * @watchdog_dev_tracker: refcount tracker used by watchdog. + * @dev_registered_tracker: tracker for reference held while + * registered * * FIXME: cleanup struct net_device such that network protocol info * moves out. @@ -2282,6 +2284,7 @@ struct net_device { u8 dev_addr_shadow[MAX_ADDR_LEN]; netdevice_tracker linkwatch_dev_tracker; netdevice_tracker watchdog_dev_tracker; + netdevice_tracker dev_registered_tracker; }; #define to_net_dev(d) container_of(d, struct net_device, dev) diff --git a/net/core/dev.c b/net/core/dev.c index f662c6a7d7b4..66556a21800a 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -9683,8 +9683,10 @@ int register_netdevice(struct net_device *dev) linkwatch_init_dev(dev); dev_init_scheduler(dev); - dev_hold(dev); + + dev_hold_track(dev, &dev->dev_registered_tracker, GFP_KERNEL); list_netdevice(dev); + add_device_randomness(dev->dev_addr, dev->addr_len); /* If the device has permanent device address, driver should @@ -10449,7 +10451,7 @@ void unregister_netdevice_many(struct list_head *head) synchronize_net(); list_for_each_entry(dev, head, unreg_list) { - dev_put(dev); + dev_put_track(dev, &dev->dev_registered_tracker); net_set_todo(dev); } -- cgit v1.3-14-g43fede From 5891cd5ec46c2c2eb6427cb54d214b149635dd0e Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 11 Feb 2022 12:06:23 -0800 Subject: net_sched: add __rcu annotation to netdev->qdisc syzbot found a data-race [1] which lead me to add __rcu annotations to netdev->qdisc, and proper accessors to get LOCKDEP support. [1] BUG: KCSAN: data-race in dev_activate / qdisc_lookup_rcu write to 0xffff888168ad6410 of 8 bytes by task 13559 on cpu 1: attach_default_qdiscs net/sched/sch_generic.c:1167 [inline] dev_activate+0x2ed/0x8f0 net/sched/sch_generic.c:1221 __dev_open+0x2e9/0x3a0 net/core/dev.c:1416 __dev_change_flags+0x167/0x3f0 net/core/dev.c:8139 rtnl_configure_link+0xc2/0x150 net/core/rtnetlink.c:3150 __rtnl_newlink net/core/rtnetlink.c:3489 [inline] rtnl_newlink+0xf4d/0x13e0 net/core/rtnetlink.c:3529 rtnetlink_rcv_msg+0x745/0x7e0 net/core/rtnetlink.c:5594 netlink_rcv_skb+0x14e/0x250 net/netlink/af_netlink.c:2494 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5612 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x602/0x6d0 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x728/0x850 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg net/socket.c:725 [inline] ____sys_sendmsg+0x39a/0x510 net/socket.c:2413 ___sys_sendmsg net/socket.c:2467 [inline] __sys_sendmsg+0x195/0x230 net/socket.c:2496 __do_sys_sendmsg net/socket.c:2505 [inline] __se_sys_sendmsg net/socket.c:2503 [inline] __x64_sys_sendmsg+0x42/0x50 net/socket.c:2503 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff888168ad6410 of 8 bytes by task 13560 on cpu 0: qdisc_lookup_rcu+0x30/0x2e0 net/sched/sch_api.c:323 __tcf_qdisc_find+0x74/0x3a0 net/sched/cls_api.c:1050 tc_del_tfilter+0x1c7/0x1350 net/sched/cls_api.c:2211 rtnetlink_rcv_msg+0x5ba/0x7e0 net/core/rtnetlink.c:5585 netlink_rcv_skb+0x14e/0x250 net/netlink/af_netlink.c:2494 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5612 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x602/0x6d0 net/netlink/af_netlink.c:1343 netlink_sendmsg+0x728/0x850 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg net/socket.c:725 [inline] ____sys_sendmsg+0x39a/0x510 net/socket.c:2413 ___sys_sendmsg net/socket.c:2467 [inline] __sys_sendmsg+0x195/0x230 net/socket.c:2496 __do_sys_sendmsg net/socket.c:2505 [inline] __se_sys_sendmsg net/socket.c:2503 [inline] __x64_sys_sendmsg+0x42/0x50 net/socket.c:2503 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0xffffffff85dee080 -> 0xffff88815d96ec00 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 13560 Comm: syz-executor.2 Not tainted 5.17.0-rc3-syzkaller-00116-gf1baf68e1383-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 470502de5bdb ("net: sched: unlock rules update API") Signed-off-by: Eric Dumazet Cc: Vlad Buslov Reported-by: syzbot Cc: Jamal Hadi Salim Cc: Cong Wang Cc: Jiri Pirko Signed-off-by: David S. Miller --- include/linux/netdevice.h | 2 +- net/core/rtnetlink.c | 6 ++++-- net/sched/cls_api.c | 6 +++--- net/sched/sch_api.c | 22 ++++++++++++---------- net/sched/sch_generic.c | 29 ++++++++++++++++------------- 5 files changed, 36 insertions(+), 29 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index e490b84732d1..8b5a314db167 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2158,7 +2158,7 @@ struct net_device { struct netdev_queue *_tx ____cacheline_aligned_in_smp; unsigned int num_tx_queues; unsigned int real_num_tx_queues; - struct Qdisc *qdisc; + struct Qdisc __rcu *qdisc; unsigned int tx_queue_len; spinlock_t tx_global_lock; diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 710da8a36729..2fb8eb6791e8 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1699,6 +1699,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, { struct ifinfomsg *ifm; struct nlmsghdr *nlh; + struct Qdisc *qdisc; ASSERT_RTNL(); nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags); @@ -1716,6 +1717,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, if (tgt_netnsid >= 0 && nla_put_s32(skb, IFLA_TARGET_NETNSID, tgt_netnsid)) goto nla_put_failure; + qdisc = rtnl_dereference(dev->qdisc); if (nla_put_string(skb, IFLA_IFNAME, dev->name) || nla_put_u32(skb, IFLA_TXQLEN, dev->tx_queue_len) || nla_put_u8(skb, IFLA_OPERSTATE, @@ -1735,8 +1737,8 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, #endif put_master_ifindex(skb, dev) || nla_put_u8(skb, IFLA_CARRIER, netif_carrier_ok(dev)) || - (dev->qdisc && - nla_put_string(skb, IFLA_QDISC, dev->qdisc->ops->id)) || + (qdisc && + nla_put_string(skb, IFLA_QDISC, qdisc->ops->id)) || nla_put_ifalias(skb, dev) || nla_put_u32(skb, IFLA_CARRIER_CHANGES, atomic_read(&dev->carrier_up_count) + diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index 5f0f346b576f..5ce1208a6ea3 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -1044,7 +1044,7 @@ static int __tcf_qdisc_find(struct net *net, struct Qdisc **q, /* Find qdisc */ if (!*parent) { - *q = dev->qdisc; + *q = rcu_dereference(dev->qdisc); *parent = (*q)->handle; } else { *q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent)); @@ -2587,7 +2587,7 @@ static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) parent = tcm->tcm_parent; if (!parent) - q = dev->qdisc; + q = rtnl_dereference(dev->qdisc); else q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent)); if (!q) @@ -2962,7 +2962,7 @@ static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb) return skb->len; if (!tcm->tcm_parent) - q = dev->qdisc; + q = rtnl_dereference(dev->qdisc); else q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent)); diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index 179825a3b2fd..e3c0e8ea2dbb 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -301,7 +301,7 @@ struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle) if (!handle) return NULL; - q = qdisc_match_from_root(dev->qdisc, handle); + q = qdisc_match_from_root(rtnl_dereference(dev->qdisc), handle); if (q) goto out; @@ -320,7 +320,7 @@ struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle) if (!handle) return NULL; - q = qdisc_match_from_root(dev->qdisc, handle); + q = qdisc_match_from_root(rcu_dereference(dev->qdisc), handle); if (q) goto out; @@ -1082,10 +1082,10 @@ static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, skip: if (!ingress) { notify_and_destroy(net, skb, n, classid, - dev->qdisc, new); + rtnl_dereference(dev->qdisc), new); if (new && !new->ops->attach) qdisc_refcount_inc(new); - dev->qdisc = new ? : &noop_qdisc; + rcu_assign_pointer(dev->qdisc, new ? : &noop_qdisc); if (new && new->ops->attach) new->ops->attach(new); @@ -1451,7 +1451,7 @@ static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, q = dev_ingress_queue(dev)->qdisc_sleeping; } } else { - q = dev->qdisc; + q = rtnl_dereference(dev->qdisc); } if (!q) { NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device"); @@ -1540,7 +1540,7 @@ replay: q = dev_ingress_queue(dev)->qdisc_sleeping; } } else { - q = dev->qdisc; + q = rtnl_dereference(dev->qdisc); } /* It may be default qdisc, ignore it */ @@ -1762,7 +1762,8 @@ static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) s_q_idx = 0; q_idx = 0; - if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx, + if (tc_dump_qdisc_root(rtnl_dereference(dev->qdisc), + skb, cb, &q_idx, s_q_idx, true, tca[TCA_DUMP_INVISIBLE]) < 0) goto done; @@ -2033,7 +2034,7 @@ static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, } else if (qid1) { qid = qid1; } else if (qid == 0) - qid = dev->qdisc->handle; + qid = rtnl_dereference(dev->qdisc)->handle; /* Now qid is genuine qdisc handle consistent * both with parent and child. @@ -2044,7 +2045,7 @@ static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, portid = TC_H_MAKE(qid, portid); } else { if (qid == 0) - qid = dev->qdisc->handle; + qid = rtnl_dereference(dev->qdisc)->handle; } /* OK. Locate qdisc */ @@ -2205,7 +2206,8 @@ static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) s_t = cb->args[0]; t = 0; - if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t, true) < 0) + if (tc_dump_tclass_root(rtnl_dereference(dev->qdisc), + skb, tcm, cb, &t, s_t, true) < 0) goto done; dev_queue = dev_ingress_queue(dev); diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index f893d9a81b01..5bab9f8b8f45 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -1164,30 +1164,33 @@ static void attach_default_qdiscs(struct net_device *dev) if (!netif_is_multiqueue(dev) || dev->priv_flags & IFF_NO_QUEUE) { netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL); - dev->qdisc = txq->qdisc_sleeping; - qdisc_refcount_inc(dev->qdisc); + qdisc = txq->qdisc_sleeping; + rcu_assign_pointer(dev->qdisc, qdisc); + qdisc_refcount_inc(qdisc); } else { qdisc = qdisc_create_dflt(txq, &mq_qdisc_ops, TC_H_ROOT, NULL); if (qdisc) { - dev->qdisc = qdisc; + rcu_assign_pointer(dev->qdisc, qdisc); qdisc->ops->attach(qdisc); } } + qdisc = rtnl_dereference(dev->qdisc); /* Detect default qdisc setup/init failed and fallback to "noqueue" */ - if (dev->qdisc == &noop_qdisc) { + if (qdisc == &noop_qdisc) { netdev_warn(dev, "default qdisc (%s) fail, fallback to %s\n", default_qdisc_ops->id, noqueue_qdisc_ops.id); dev->priv_flags |= IFF_NO_QUEUE; netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL); - dev->qdisc = txq->qdisc_sleeping; - qdisc_refcount_inc(dev->qdisc); + qdisc = txq->qdisc_sleeping; + rcu_assign_pointer(dev->qdisc, qdisc); + qdisc_refcount_inc(qdisc); dev->priv_flags ^= IFF_NO_QUEUE; } #ifdef CONFIG_NET_SCHED - if (dev->qdisc != &noop_qdisc) - qdisc_hash_add(dev->qdisc, false); + if (qdisc != &noop_qdisc) + qdisc_hash_add(qdisc, false); #endif } @@ -1217,7 +1220,7 @@ void dev_activate(struct net_device *dev) * and noqueue_qdisc for virtual interfaces */ - if (dev->qdisc == &noop_qdisc) + if (rtnl_dereference(dev->qdisc) == &noop_qdisc) attach_default_qdiscs(dev); if (!netif_carrier_ok(dev)) @@ -1383,7 +1386,7 @@ static int qdisc_change_tx_queue_len(struct net_device *dev, void dev_qdisc_change_real_num_tx(struct net_device *dev, unsigned int new_real_tx) { - struct Qdisc *qdisc = dev->qdisc; + struct Qdisc *qdisc = rtnl_dereference(dev->qdisc); if (qdisc->ops->change_real_num_tx) qdisc->ops->change_real_num_tx(qdisc, new_real_tx); @@ -1447,7 +1450,7 @@ static void dev_init_scheduler_queue(struct net_device *dev, void dev_init_scheduler(struct net_device *dev) { - dev->qdisc = &noop_qdisc; + rcu_assign_pointer(dev->qdisc, &noop_qdisc); netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc); if (dev_ingress_queue(dev)) dev_init_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); @@ -1475,8 +1478,8 @@ void dev_shutdown(struct net_device *dev) netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc); if (dev_ingress_queue(dev)) shutdown_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); - qdisc_put(dev->qdisc); - dev->qdisc = &noop_qdisc; + qdisc_put(rtnl_dereference(dev->qdisc)); + rcu_assign_pointer(dev->qdisc, &noop_qdisc); WARN_ON(timer_pending(&dev->watchdog_timer)); } -- cgit v1.3-14-g43fede From baebdf48c360080710f80699eea3affbb13d6c65 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Sat, 12 Feb 2022 00:38:38 +0100 Subject: net: dev: Makes sure netif_rx() can be invoked in any context. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Dave suggested a while ago (eleven years by now) "Let's make netif_rx() work in all contexts and get rid of netif_rx_ni()". Eric agreed and pointed out that modern devices should use netif_receive_skb() to avoid the overhead. In the meantime someone added another variant, netif_rx_any_context(), which behaves as suggested. netif_rx() must be invoked with disabled bottom halves to ensure that pending softirqs, which were raised within the function, are handled. netif_rx_ni() can be invoked only from process context (bottom halves must be enabled) because the function handles pending softirqs without checking if bottom halves were disabled or not. netif_rx_any_context() invokes on the former functions by checking in_interrupts(). netif_rx() could be taught to handle both cases (disabled and enabled bottom halves) by simply disabling bottom halves while invoking netif_rx_internal(). The local_bh_enable() invocation will then invoke pending softirqs only if the BH-disable counter drops to zero. Eric is concerned about the overhead of BH-disable+enable especially in regard to the loopback driver. As critical as this driver is, it will receive a shortcut to avoid the additional overhead which is not needed. Add a local_bh_disable() section in netif_rx() to ensure softirqs are handled if needed. Provide __netif_rx() which does not disable BH and has a lockdep assert to ensure that interrupts are disabled. Use this shortcut in the loopback driver and in drivers/net/*.c. Make netif_rx_ni() and netif_rx_any_context() invoke netif_rx() so they can be removed once they are no more users left. Link: https://lkml.kernel.org/r/20100415.020246.218622820.davem@davemloft.net Signed-off-by: Sebastian Andrzej Siewior Reviewed-by: Eric Dumazet Reviewed-by: Toke Høiland-Jørgensen Signed-off-by: David S. Miller --- drivers/net/amt.c | 4 +-- drivers/net/geneve.c | 4 +-- drivers/net/gtp.c | 2 +- drivers/net/loopback.c | 4 +-- drivers/net/macsec.c | 6 ++--- drivers/net/macvlan.c | 4 +-- drivers/net/mhi_net.c | 2 +- drivers/net/ntb_netdev.c | 2 +- drivers/net/rionet.c | 2 +- drivers/net/sb1000.c | 2 +- drivers/net/veth.c | 2 +- drivers/net/vrf.c | 2 +- drivers/net/vxlan.c | 2 +- include/linux/netdevice.h | 14 ++++++++-- include/trace/events/net.h | 14 ---------- net/core/dev.c | 67 ++++++++++++++++++++-------------------------- 16 files changed, 60 insertions(+), 73 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/drivers/net/amt.c b/drivers/net/amt.c index f1a36d7e2151..10455c9b9da0 100644 --- a/drivers/net/amt.c +++ b/drivers/net/amt.c @@ -2373,7 +2373,7 @@ static bool amt_membership_query_handler(struct amt_dev *amt, skb->pkt_type = PACKET_MULTICAST; skb->ip_summed = CHECKSUM_NONE; len = skb->len; - if (netif_rx(skb) == NET_RX_SUCCESS) { + if (__netif_rx(skb) == NET_RX_SUCCESS) { amt_update_gw_status(amt, AMT_STATUS_RECEIVED_QUERY, true); dev_sw_netstats_rx_add(amt->dev, len); } else { @@ -2470,7 +2470,7 @@ report: skb->pkt_type = PACKET_MULTICAST; skb->ip_summed = CHECKSUM_NONE; len = skb->len; - if (netif_rx(skb) == NET_RX_SUCCESS) { + if (__netif_rx(skb) == NET_RX_SUCCESS) { amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_UPDATE, true); dev_sw_netstats_rx_add(amt->dev, len); diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index c1fdd721a730..a895ff756093 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -925,7 +925,7 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev, } skb->protocol = eth_type_trans(skb, geneve->dev); - netif_rx(skb); + __netif_rx(skb); dst_release(&rt->dst); return -EMSGSIZE; } @@ -1021,7 +1021,7 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev, } skb->protocol = eth_type_trans(skb, geneve->dev); - netif_rx(skb); + __netif_rx(skb); dst_release(dst); return -EMSGSIZE; } diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c index 24e5c54d06c1..bf087171bcf0 100644 --- a/drivers/net/gtp.c +++ b/drivers/net/gtp.c @@ -207,7 +207,7 @@ static int gtp_rx(struct pdp_ctx *pctx, struct sk_buff *skb, dev_sw_netstats_rx_add(pctx->dev, skb->len); - netif_rx(skb); + __netif_rx(skb); return 0; err: diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index ed0edf5884ef..d05f86fe78c9 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -78,7 +78,7 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb, skb_orphan(skb); - /* Before queueing this packet to netif_rx(), + /* Before queueing this packet to __netif_rx(), * make sure dst is refcounted. */ skb_dst_force(skb); @@ -86,7 +86,7 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb, skb->protocol = eth_type_trans(skb, dev); len = skb->len; - if (likely(netif_rx(skb) == NET_RX_SUCCESS)) + if (likely(__netif_rx(skb) == NET_RX_SUCCESS)) dev_lstats_add(dev, len); return NETDEV_TX_OK; diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index 3d0874331763..832f09ac075e 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -1033,7 +1033,7 @@ static enum rx_handler_result handle_not_macsec(struct sk_buff *skb) else nskb->pkt_type = PACKET_MULTICAST; - netif_rx(nskb); + __netif_rx(nskb); } continue; } @@ -1056,7 +1056,7 @@ static enum rx_handler_result handle_not_macsec(struct sk_buff *skb) nskb->dev = ndev; - if (netif_rx(nskb) == NET_RX_SUCCESS) { + if (__netif_rx(nskb) == NET_RX_SUCCESS) { u64_stats_update_begin(&secy_stats->syncp); secy_stats->stats.InPktsUntagged++; u64_stats_update_end(&secy_stats->syncp); @@ -1288,7 +1288,7 @@ nosci: macsec_reset_skb(nskb, macsec->secy.netdev); - ret = netif_rx(nskb); + ret = __netif_rx(nskb); if (ret == NET_RX_SUCCESS) { u64_stats_update_begin(&secy_stats->syncp); secy_stats->stats.InPktsUnknownSCI++; diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 6ef5f77be4d0..d87c06c317ed 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -410,7 +410,7 @@ static void macvlan_forward_source_one(struct sk_buff *skb, if (ether_addr_equal_64bits(eth_hdr(skb)->h_dest, dev->dev_addr)) nskb->pkt_type = PACKET_HOST; - ret = netif_rx(nskb); + ret = __netif_rx(nskb); macvlan_count_rx(vlan, len, ret == NET_RX_SUCCESS, false); } @@ -468,7 +468,7 @@ static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb) /* forward to original port. */ vlan = src; ret = macvlan_broadcast_one(skb, vlan, eth, 0) ?: - netif_rx(skb); + __netif_rx(skb); handle_res = RX_HANDLER_CONSUMED; goto out; } diff --git a/drivers/net/mhi_net.c b/drivers/net/mhi_net.c index aaa628f859fd..0b1b6f650104 100644 --- a/drivers/net/mhi_net.c +++ b/drivers/net/mhi_net.c @@ -225,7 +225,7 @@ static void mhi_net_dl_callback(struct mhi_device *mhi_dev, u64_stats_inc(&mhi_netdev->stats.rx_packets); u64_stats_add(&mhi_netdev->stats.rx_bytes, skb->len); u64_stats_update_end(&mhi_netdev->stats.rx_syncp); - netif_rx(skb); + __netif_rx(skb); } /* Refill if RX buffers queue becomes low */ diff --git a/drivers/net/ntb_netdev.c b/drivers/net/ntb_netdev.c index 98ca6b18415e..80bdc07f2cd3 100644 --- a/drivers/net/ntb_netdev.c +++ b/drivers/net/ntb_netdev.c @@ -119,7 +119,7 @@ static void ntb_netdev_rx_handler(struct ntb_transport_qp *qp, void *qp_data, skb->protocol = eth_type_trans(skb, ndev); skb->ip_summed = CHECKSUM_NONE; - if (netif_rx(skb) == NET_RX_DROP) { + if (__netif_rx(skb) == NET_RX_DROP) { ndev->stats.rx_errors++; ndev->stats.rx_dropped++; } else { diff --git a/drivers/net/rionet.c b/drivers/net/rionet.c index 1a95f3beb784..39e61e07e489 100644 --- a/drivers/net/rionet.c +++ b/drivers/net/rionet.c @@ -109,7 +109,7 @@ static int rionet_rx_clean(struct net_device *ndev) skb_put(rnet->rx_skb[i], RIO_MAX_MSG_SIZE); rnet->rx_skb[i]->protocol = eth_type_trans(rnet->rx_skb[i], ndev); - error = netif_rx(rnet->rx_skb[i]); + error = __netif_rx(rnet->rx_skb[i]); if (error == NET_RX_DROP) { ndev->stats.rx_dropped++; diff --git a/drivers/net/sb1000.c b/drivers/net/sb1000.c index 57a6d598467b..c3f8020571ad 100644 --- a/drivers/net/sb1000.c +++ b/drivers/net/sb1000.c @@ -872,7 +872,7 @@ printk("cm0: IP identification: %02x%02x fragment offset: %02x%02x\n", buffer[3 /* datagram completed: send to upper level */ skb_trim(skb, dlen); - netif_rx(skb); + __netif_rx(skb); stats->rx_bytes+=dlen; stats->rx_packets++; lp->rx_skb[ns] = NULL; diff --git a/drivers/net/veth.c b/drivers/net/veth.c index d29fb9759cc9..58b20ea171dd 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -287,7 +287,7 @@ static int veth_forward_skb(struct net_device *dev, struct sk_buff *skb, { return __dev_forward_skb(dev, skb) ?: xdp ? veth_xdp_rx(rq, skb) : - netif_rx(skb); + __netif_rx(skb); } /* return true if the specified skb has chances of GRO aggregation diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c index e0b1ab99a359..714cafcf6c6c 100644 --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -418,7 +418,7 @@ static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev, skb->protocol = eth_type_trans(skb, dev); - if (likely(netif_rx(skb) == NET_RX_SUCCESS)) + if (likely(__netif_rx(skb) == NET_RX_SUCCESS)) vrf_rx_stats(dev, len); else this_cpu_inc(dev->dstats->rx_drps); diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 359d16780dbb..d0dc90d3dac2 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -2541,7 +2541,7 @@ static void vxlan_encap_bypass(struct sk_buff *skb, struct vxlan_dev *src_vxlan, tx_stats->tx_bytes += len; u64_stats_update_end(&tx_stats->syncp); - if (netif_rx(skb) == NET_RX_SUCCESS) { + if (__netif_rx(skb) == NET_RX_SUCCESS) { u64_stats_update_begin(&rx_stats->syncp); rx_stats->rx_packets++; rx_stats->rx_bytes += len; diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 5f6e2c0b0c90..e99db8341da5 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3672,8 +3672,18 @@ u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog); int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb); int netif_rx(struct sk_buff *skb); -int netif_rx_ni(struct sk_buff *skb); -int netif_rx_any_context(struct sk_buff *skb); +int __netif_rx(struct sk_buff *skb); + +static inline int netif_rx_ni(struct sk_buff *skb) +{ + return netif_rx(skb); +} + +static inline int netif_rx_any_context(struct sk_buff *skb) +{ + return netif_rx(skb); +} + int netif_receive_skb(struct sk_buff *skb); int netif_receive_skb_core(struct sk_buff *skb); void netif_receive_skb_list_internal(struct list_head *head); diff --git a/include/trace/events/net.h b/include/trace/events/net.h index 78c448c6ab4c..032b431b987b 100644 --- a/include/trace/events/net.h +++ b/include/trace/events/net.h @@ -260,13 +260,6 @@ DEFINE_EVENT(net_dev_rx_verbose_template, netif_rx_entry, TP_ARGS(skb) ); -DEFINE_EVENT(net_dev_rx_verbose_template, netif_rx_ni_entry, - - TP_PROTO(const struct sk_buff *skb), - - TP_ARGS(skb) -); - DECLARE_EVENT_CLASS(net_dev_rx_exit_template, TP_PROTO(int ret), @@ -312,13 +305,6 @@ DEFINE_EVENT(net_dev_rx_exit_template, netif_rx_exit, TP_ARGS(ret) ); -DEFINE_EVENT(net_dev_rx_exit_template, netif_rx_ni_exit, - - TP_PROTO(int ret), - - TP_ARGS(ret) -); - DEFINE_EVENT(net_dev_rx_exit_template, netif_receive_skb_list_exit, TP_PROTO(int ret), diff --git a/net/core/dev.c b/net/core/dev.c index 441bacf79199..ce5047e8db1f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4815,66 +4815,57 @@ static int netif_rx_internal(struct sk_buff *skb) return ret; } +/** + * __netif_rx - Slightly optimized version of netif_rx + * @skb: buffer to post + * + * This behaves as netif_rx except that it does not disable bottom halves. + * As a result this function may only be invoked from the interrupt context + * (either hard or soft interrupt). + */ +int __netif_rx(struct sk_buff *skb) +{ + int ret; + + lockdep_assert_once(hardirq_count() | softirq_count()); + + trace_netif_rx_entry(skb); + ret = netif_rx_internal(skb); + trace_netif_rx_exit(ret); + return ret; +} +EXPORT_SYMBOL(__netif_rx); + /** * netif_rx - post buffer to the network code * @skb: buffer to post * * This function receives a packet from a device driver and queues it for - * the upper (protocol) levels to process. It always succeeds. The buffer - * may be dropped during processing for congestion control or by the - * protocol layers. + * the upper (protocol) levels to process via the backlog NAPI device. It + * always succeeds. The buffer may be dropped during processing for + * congestion control or by the protocol layers. + * The network buffer is passed via the backlog NAPI device. Modern NIC + * driver should use NAPI and GRO. + * This function can used from any context. * * return values: * NET_RX_SUCCESS (no congestion) * NET_RX_DROP (packet was dropped) * */ - int netif_rx(struct sk_buff *skb) { int ret; + local_bh_disable(); trace_netif_rx_entry(skb); - ret = netif_rx_internal(skb); trace_netif_rx_exit(ret); - + local_bh_enable(); return ret; } EXPORT_SYMBOL(netif_rx); -int netif_rx_ni(struct sk_buff *skb) -{ - int err; - - trace_netif_rx_ni_entry(skb); - - preempt_disable(); - err = netif_rx_internal(skb); - if (local_softirq_pending()) - do_softirq(); - preempt_enable(); - trace_netif_rx_ni_exit(err); - - return err; -} -EXPORT_SYMBOL(netif_rx_ni); - -int netif_rx_any_context(struct sk_buff *skb) -{ - /* - * If invoked from contexts which do not invoke bottom half - * processing either at return from interrupt or when softrqs are - * reenabled, use netif_rx_ni() which invokes bottomhalf processing - * directly. - */ - if (in_interrupt()) - return netif_rx(skb); - else - return netif_rx_ni(skb); -} -EXPORT_SYMBOL(netif_rx_any_context); - static __latent_entropy void net_tx_action(struct softirq_action *h) { struct softnet_data *sd = this_cpu_ptr(&softnet_data); -- cgit v1.3-14-g43fede From b26ef81c46ed15d11ddddba9ba1cd52c749385ad Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 22 Feb 2022 14:04:50 -0800 Subject: drop_monitor: remove quadratic behavior drop_monitor is using an unique list on which all netdevices in the host have an element, regardless of their netns. This scales poorly, not only at device unregister time (what I caught during my netns dismantle stress tests), but also at packet processing time whenever trace_napi_poll_hit() is called. If the intent was to avoid adding one pointer in 'struct net_device' then surely we prefer O(1) behavior. Signed-off-by: Eric Dumazet Cc: Neil Horman Signed-off-by: David S. Miller --- include/linux/netdevice.h | 4 ++- net/core/drop_monitor.c | 79 ++++++++++++++--------------------------------- 2 files changed, 27 insertions(+), 56 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 93fc680b658f..c79ee2296296 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2236,7 +2236,9 @@ struct net_device { #if IS_ENABLED(CONFIG_MRP) struct mrp_port __rcu *mrp_port; #endif - +#if IS_ENABLED(CONFIG_NET_DROP_MONITOR) + struct dm_hw_stat_delta __rcu *dm_private; +#endif struct device dev; const struct attribute_group *sysfs_groups[4]; const struct attribute_group *sysfs_rx_queue_group; diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c index d7d177f75d43..b89e3e95bffc 100644 --- a/net/core/drop_monitor.c +++ b/net/core/drop_monitor.c @@ -64,7 +64,6 @@ static const char * const drop_reasons[] = { /* net_dm_mutex * * An overall lock guarding every operation coming from userspace. - * It also guards the global 'hw_stats_list' list. */ static DEFINE_MUTEX(net_dm_mutex); @@ -100,11 +99,9 @@ struct per_cpu_dm_data { }; struct dm_hw_stat_delta { - struct net_device *dev; unsigned long last_rx; - struct list_head list; - struct rcu_head rcu; unsigned long last_drop_val; + struct rcu_head rcu; }; static struct genl_family net_drop_monitor_family; @@ -115,7 +112,6 @@ static DEFINE_PER_CPU(struct per_cpu_dm_data, dm_hw_cpu_data); static int dm_hit_limit = 64; static int dm_delay = 1; static unsigned long dm_hw_check_delta = 2*HZ; -static LIST_HEAD(hw_stats_list); static enum net_dm_alert_mode net_dm_alert_mode = NET_DM_ALERT_MODE_SUMMARY; static u32 net_dm_trunc_len; @@ -287,33 +283,27 @@ static void trace_kfree_skb_hit(void *ignore, struct sk_buff *skb, static void trace_napi_poll_hit(void *ignore, struct napi_struct *napi, int work, int budget) { - struct dm_hw_stat_delta *new_stat; - + struct net_device *dev = napi->dev; + struct dm_hw_stat_delta *stat; /* * Don't check napi structures with no associated device */ - if (!napi->dev) + if (!dev) return; rcu_read_lock(); - list_for_each_entry_rcu(new_stat, &hw_stats_list, list) { - struct net_device *dev; - + stat = rcu_dereference(dev->dm_private); + if (stat) { /* * only add a note to our monitor buffer if: - * 1) this is the dev we received on - * 2) its after the last_rx delta - * 3) our rx_dropped count has gone up + * 1) its after the last_rx delta + * 2) our rx_dropped count has gone up */ - /* Paired with WRITE_ONCE() in dropmon_net_event() */ - dev = READ_ONCE(new_stat->dev); - if ((dev == napi->dev) && - (time_after(jiffies, new_stat->last_rx + dm_hw_check_delta)) && - (napi->dev->stats.rx_dropped != new_stat->last_drop_val)) { + if (time_after(jiffies, stat->last_rx + dm_hw_check_delta) && + (dev->stats.rx_dropped != stat->last_drop_val)) { trace_drop_common(NULL, NULL); - new_stat->last_drop_val = napi->dev->stats.rx_dropped; - new_stat->last_rx = jiffies; - break; + stat->last_drop_val = dev->stats.rx_dropped; + stat->last_rx = jiffies; } } rcu_read_unlock(); @@ -1198,7 +1188,6 @@ err_module_put: static void net_dm_trace_off_set(void) { - struct dm_hw_stat_delta *new_stat, *temp; const struct net_dm_alert_ops *ops; int cpu; @@ -1222,13 +1211,6 @@ static void net_dm_trace_off_set(void) consume_skb(skb); } - list_for_each_entry_safe(new_stat, temp, &hw_stats_list, list) { - if (new_stat->dev == NULL) { - list_del_rcu(&new_stat->list); - kfree_rcu(new_stat, rcu); - } - } - module_put(THIS_MODULE); } @@ -1589,41 +1571,28 @@ static int dropmon_net_event(struct notifier_block *ev_block, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); - struct dm_hw_stat_delta *new_stat = NULL; - struct dm_hw_stat_delta *tmp; + struct dm_hw_stat_delta *stat; switch (event) { case NETDEV_REGISTER: - new_stat = kzalloc(sizeof(struct dm_hw_stat_delta), GFP_KERNEL); + if (WARN_ON_ONCE(rtnl_dereference(dev->dm_private))) + break; + stat = kzalloc(sizeof(*stat), GFP_KERNEL); + if (!stat) + break; - if (!new_stat) - goto out; + stat->last_rx = jiffies; + rcu_assign_pointer(dev->dm_private, stat); - new_stat->dev = dev; - new_stat->last_rx = jiffies; - mutex_lock(&net_dm_mutex); - list_add_rcu(&new_stat->list, &hw_stats_list); - mutex_unlock(&net_dm_mutex); break; case NETDEV_UNREGISTER: - mutex_lock(&net_dm_mutex); - list_for_each_entry_safe(new_stat, tmp, &hw_stats_list, list) { - if (new_stat->dev == dev) { - - /* Paired with READ_ONCE() in trace_napi_poll_hit() */ - WRITE_ONCE(new_stat->dev, NULL); - - if (trace_state == TRACE_OFF) { - list_del_rcu(&new_stat->list); - kfree_rcu(new_stat, rcu); - break; - } - } + stat = rtnl_dereference(dev->dm_private); + if (stat) { + rcu_assign_pointer(dev->dm_private, NULL); + kfree_rcu(stat, rcu); } - mutex_unlock(&net_dm_mutex); break; } -out: return NOTIFY_DONE; } -- cgit v1.3-14-g43fede From 9309f97aef6d8250bb484dabeac925c3a7c57716 Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Wed, 2 Mar 2022 18:31:20 +0200 Subject: net: dev: Add hardware stats support Offloading switch device drivers may be able to collect statistics of the traffic taking place in the HW datapath that pertains to a certain soft netdevice, such as VLAN. Add the necessary infrastructure to allow exposing these statistics to the offloaded netdevice in question. The API was shaped by the following considerations: - Collection of HW statistics is not free: there may be a finite number of counters, and the act of counting may have a performance impact. It is therefore necessary to allow toggling whether HW counting should be done for any particular SW netdevice. - As the drivers are loaded and removed, a particular device may get offloaded and unoffloaded again. At the same time, the statistics values need to stay monotonic (modulo the eventual 64-bit wraparound), increasing only to reflect traffic measured in the device. To that end, the netdevice keeps around a lazily-allocated copy of struct rtnl_link_stats64. Device drivers then contribute to the values kept therein at various points. Even as the driver goes away, the struct stays around to maintain the statistics values. - Different HW devices may be able to count different things. The motivation behind this patch in particular is exposure of HW counters on Nvidia Spectrum switches, where the only practical approach to counting traffic on offloaded soft netdevices currently is to use router interface counters, and count L3 traffic. Correspondingly that is the statistics suite added in this patch. Other devices may be able to measure different kinds of traffic, and for that reason, the APIs are built to allow uniform access to different statistics suites. - Because soft netdevices and offloading drivers are only loosely bound, a netdevice uses a notifier chain to communicate with the drivers. Several new notifiers, NETDEV_OFFLOAD_XSTATS_*, have been added to carry messages to the offloading drivers. - Devices can have various conditions for when a particular counter is available. As the device is configured and reconfigured, the device offload may become or cease being suitable for counter binding. A netdevice can use a notifier type NETDEV_OFFLOAD_XSTATS_REPORT_USED to ping offloading drivers and determine whether anyone currently implements a given statistics suite. This information can then be propagated to user space. When the driver decides to unoffload a netdevice, it can use a newly-added function, netdev_offload_xstats_report_delta(), to record outstanding collected statistics, before destroying the HW counter. This patch adds a helper, call_netdevice_notifiers_info_robust(), for dispatching a notifier with the possibility of unwind when one of the consumers bails. Given the wish to eventually get rid of the global notifier block altogether, this helper only invokes the per-netns notifier block. Signed-off-by: Petr Machata Signed-off-by: Ido Schimmel Signed-off-by: David S. Miller --- include/linux/netdevice.h | 42 +++++++ include/uapi/linux/if_link.h | 15 +++ net/core/dev.c | 267 ++++++++++++++++++++++++++++++++++++++++++- 3 files changed, 323 insertions(+), 1 deletion(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index c79ee2296296..19a27ac361ef 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1950,6 +1950,7 @@ enum netdev_ml_priv_type { * @watchdog_dev_tracker: refcount tracker used by watchdog. * @dev_registered_tracker: tracker for reference held while * registered + * @offload_xstats_l3: L3 HW stats for this netdevice. * * FIXME: cleanup struct net_device such that network protocol info * moves out. @@ -2287,6 +2288,7 @@ struct net_device { netdevice_tracker linkwatch_dev_tracker; netdevice_tracker watchdog_dev_tracker; netdevice_tracker dev_registered_tracker; + struct rtnl_hw_stats64 *offload_xstats_l3; }; #define to_net_dev(d) container_of(d, struct net_device, dev) @@ -2727,6 +2729,10 @@ enum netdev_cmd { NETDEV_CVLAN_FILTER_DROP_INFO, NETDEV_SVLAN_FILTER_PUSH_INFO, NETDEV_SVLAN_FILTER_DROP_INFO, + NETDEV_OFFLOAD_XSTATS_ENABLE, + NETDEV_OFFLOAD_XSTATS_DISABLE, + NETDEV_OFFLOAD_XSTATS_REPORT_USED, + NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, }; const char *netdev_cmd_to_name(enum netdev_cmd cmd); @@ -2777,6 +2783,42 @@ struct netdev_notifier_pre_changeaddr_info { const unsigned char *dev_addr; }; +enum netdev_offload_xstats_type { + NETDEV_OFFLOAD_XSTATS_TYPE_L3 = 1, +}; + +struct netdev_notifier_offload_xstats_info { + struct netdev_notifier_info info; /* must be first */ + enum netdev_offload_xstats_type type; + + union { + /* NETDEV_OFFLOAD_XSTATS_REPORT_DELTA */ + struct netdev_notifier_offload_xstats_rd *report_delta; + /* NETDEV_OFFLOAD_XSTATS_REPORT_USED */ + struct netdev_notifier_offload_xstats_ru *report_used; + }; +}; + +int netdev_offload_xstats_enable(struct net_device *dev, + enum netdev_offload_xstats_type type, + struct netlink_ext_ack *extack); +int netdev_offload_xstats_disable(struct net_device *dev, + enum netdev_offload_xstats_type type); +bool netdev_offload_xstats_enabled(const struct net_device *dev, + enum netdev_offload_xstats_type type); +int netdev_offload_xstats_get(struct net_device *dev, + enum netdev_offload_xstats_type type, + struct rtnl_hw_stats64 *stats, bool *used, + struct netlink_ext_ack *extack); +void +netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *rd, + const struct rtnl_hw_stats64 *stats); +void +netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *ru); +void netdev_offload_xstats_push_delta(struct net_device *dev, + enum netdev_offload_xstats_type type, + const struct rtnl_hw_stats64 *stats); + static inline void netdev_notifier_info_init(struct netdev_notifier_info *info, struct net_device *dev) { diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 4d62ea6e1288..ef6a62a2e15d 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -245,6 +245,21 @@ struct rtnl_link_stats64 { __u64 rx_nohandler; }; +/* Subset of link stats useful for in-HW collection. Meaning of the fields is as + * for struct rtnl_link_stats64. + */ +struct rtnl_hw_stats64 { + __u64 rx_packets; + __u64 tx_packets; + __u64 rx_bytes; + __u64 tx_bytes; + __u64 rx_errors; + __u64 tx_errors; + __u64 rx_dropped; + __u64 tx_dropped; + __u64 multicast; +}; + /* The struct should be in sync with struct ifmap */ struct rtnl_link_ifmap { __u64 mem_start; diff --git a/net/core/dev.c b/net/core/dev.c index 2d6771075720..c9e54e5ad48d 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1622,7 +1622,8 @@ const char *netdev_cmd_to_name(enum netdev_cmd cmd) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN) N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO) N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) - N(PRE_CHANGEADDR) + N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) + N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) } #undef N return "UNKNOWN_NETDEV_EVENT"; @@ -1939,6 +1940,32 @@ static int call_netdevice_notifiers_info(unsigned long val, return raw_notifier_call_chain(&netdev_chain, val, info); } +/** + * call_netdevice_notifiers_info_robust - call per-netns notifier blocks + * for and rollback on error + * @val_up: value passed unmodified to notifier function + * @val_down: value passed unmodified to the notifier function when + * recovering from an error on @val_up + * @info: notifier information data + * + * Call all per-netns network notifier blocks, but not notifier blocks on + * the global notifier chain. Parameters and return value are as for + * raw_notifier_call_chain_robust(). + */ + +static int +call_netdevice_notifiers_info_robust(unsigned long val_up, + unsigned long val_down, + struct netdev_notifier_info *info) +{ + struct net *net = dev_net(info->dev); + + ASSERT_RTNL(); + + return raw_notifier_call_chain_robust(&net->netdev_chain, + val_up, val_down, info); +} + static int call_netdevice_notifiers_extack(unsigned long val, struct net_device *dev, struct netlink_ext_ack *extack) @@ -7728,6 +7755,242 @@ void netdev_bonding_info_change(struct net_device *dev, } EXPORT_SYMBOL(netdev_bonding_info_change); +static int netdev_offload_xstats_enable_l3(struct net_device *dev, + struct netlink_ext_ack *extack) +{ + struct netdev_notifier_offload_xstats_info info = { + .info.dev = dev, + .info.extack = extack, + .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, + }; + int err; + int rc; + + dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3), + GFP_KERNEL); + if (!dev->offload_xstats_l3) + return -ENOMEM; + + rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE, + NETDEV_OFFLOAD_XSTATS_DISABLE, + &info.info); + err = notifier_to_errno(rc); + if (err) + goto free_stats; + + return 0; + +free_stats: + kfree(dev->offload_xstats_l3); + dev->offload_xstats_l3 = NULL; + return err; +} + +int netdev_offload_xstats_enable(struct net_device *dev, + enum netdev_offload_xstats_type type, + struct netlink_ext_ack *extack) +{ + ASSERT_RTNL(); + + if (netdev_offload_xstats_enabled(dev, type)) + return -EALREADY; + + switch (type) { + case NETDEV_OFFLOAD_XSTATS_TYPE_L3: + return netdev_offload_xstats_enable_l3(dev, extack); + } + + WARN_ON(1); + return -EINVAL; +} +EXPORT_SYMBOL(netdev_offload_xstats_enable); + +static void netdev_offload_xstats_disable_l3(struct net_device *dev) +{ + struct netdev_notifier_offload_xstats_info info = { + .info.dev = dev, + .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, + }; + + call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE, + &info.info); + kfree(dev->offload_xstats_l3); + dev->offload_xstats_l3 = NULL; +} + +int netdev_offload_xstats_disable(struct net_device *dev, + enum netdev_offload_xstats_type type) +{ + ASSERT_RTNL(); + + if (!netdev_offload_xstats_enabled(dev, type)) + return -EALREADY; + + switch (type) { + case NETDEV_OFFLOAD_XSTATS_TYPE_L3: + netdev_offload_xstats_disable_l3(dev); + return 0; + } + + WARN_ON(1); + return -EINVAL; +} +EXPORT_SYMBOL(netdev_offload_xstats_disable); + +static void netdev_offload_xstats_disable_all(struct net_device *dev) +{ + netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3); +} + +static struct rtnl_hw_stats64 * +netdev_offload_xstats_get_ptr(const struct net_device *dev, + enum netdev_offload_xstats_type type) +{ + switch (type) { + case NETDEV_OFFLOAD_XSTATS_TYPE_L3: + return dev->offload_xstats_l3; + } + + WARN_ON(1); + return NULL; +} + +bool netdev_offload_xstats_enabled(const struct net_device *dev, + enum netdev_offload_xstats_type type) +{ + ASSERT_RTNL(); + + return netdev_offload_xstats_get_ptr(dev, type); +} +EXPORT_SYMBOL(netdev_offload_xstats_enabled); + +struct netdev_notifier_offload_xstats_ru { + bool used; +}; + +struct netdev_notifier_offload_xstats_rd { + struct rtnl_hw_stats64 stats; + bool used; +}; + +static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest, + const struct rtnl_hw_stats64 *src) +{ + dest->rx_packets += src->rx_packets; + dest->tx_packets += src->tx_packets; + dest->rx_bytes += src->rx_bytes; + dest->tx_bytes += src->tx_bytes; + dest->rx_errors += src->rx_errors; + dest->tx_errors += src->tx_errors; + dest->rx_dropped += src->rx_dropped; + dest->tx_dropped += src->tx_dropped; + dest->multicast += src->multicast; +} + +static int netdev_offload_xstats_get_used(struct net_device *dev, + enum netdev_offload_xstats_type type, + bool *p_used, + struct netlink_ext_ack *extack) +{ + struct netdev_notifier_offload_xstats_ru report_used = {}; + struct netdev_notifier_offload_xstats_info info = { + .info.dev = dev, + .info.extack = extack, + .type = type, + .report_used = &report_used, + }; + int rc; + + WARN_ON(!netdev_offload_xstats_enabled(dev, type)); + rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED, + &info.info); + *p_used = report_used.used; + return notifier_to_errno(rc); +} + +static int netdev_offload_xstats_get_stats(struct net_device *dev, + enum netdev_offload_xstats_type type, + struct rtnl_hw_stats64 *p_stats, + bool *p_used, + struct netlink_ext_ack *extack) +{ + struct netdev_notifier_offload_xstats_rd report_delta = {}; + struct netdev_notifier_offload_xstats_info info = { + .info.dev = dev, + .info.extack = extack, + .type = type, + .report_delta = &report_delta, + }; + struct rtnl_hw_stats64 *stats; + int rc; + + stats = netdev_offload_xstats_get_ptr(dev, type); + if (WARN_ON(!stats)) + return -EINVAL; + + rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, + &info.info); + + /* Cache whatever we got, even if there was an error, otherwise the + * successful stats retrievals would get lost. + */ + netdev_hw_stats64_add(stats, &report_delta.stats); + + if (p_stats) + *p_stats = *stats; + *p_used = report_delta.used; + + return notifier_to_errno(rc); +} + +int netdev_offload_xstats_get(struct net_device *dev, + enum netdev_offload_xstats_type type, + struct rtnl_hw_stats64 *p_stats, bool *p_used, + struct netlink_ext_ack *extack) +{ + ASSERT_RTNL(); + + if (p_stats) + return netdev_offload_xstats_get_stats(dev, type, p_stats, + p_used, extack); + else + return netdev_offload_xstats_get_used(dev, type, p_used, + extack); +} +EXPORT_SYMBOL(netdev_offload_xstats_get); + +void +netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta, + const struct rtnl_hw_stats64 *stats) +{ + report_delta->used = true; + netdev_hw_stats64_add(&report_delta->stats, stats); +} +EXPORT_SYMBOL(netdev_offload_xstats_report_delta); + +void +netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used) +{ + report_used->used = true; +} +EXPORT_SYMBOL(netdev_offload_xstats_report_used); + +void netdev_offload_xstats_push_delta(struct net_device *dev, + enum netdev_offload_xstats_type type, + const struct rtnl_hw_stats64 *p_stats) +{ + struct rtnl_hw_stats64 *stats; + + ASSERT_RTNL(); + + stats = netdev_offload_xstats_get_ptr(dev, type); + if (WARN_ON(!stats)) + return; + + netdev_hw_stats64_add(stats, p_stats); +} +EXPORT_SYMBOL(netdev_offload_xstats_push_delta); + /** * netdev_get_xmit_slave - Get the xmit slave of master device * @dev: device @@ -10417,6 +10680,8 @@ void unregister_netdevice_many(struct list_head *head) dev_xdp_uninstall(dev); + netdev_offload_xstats_disable_all(dev); + /* Notify protocols, that we are about to destroy * this device. They should clean all the things. */ -- cgit v1.3-14-g43fede From 2655926aea9beea62c9ba80c032485456fd848f0 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Sun, 6 Mar 2022 22:57:52 +0100 Subject: net: Remove netif_rx_any_context() and netif_rx_ni(). Remove netif_rx_any_context and netif_rx_ni() because there are no more users in tree. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: David S. Miller --- include/linux/netdevice.h | 10 ---------- 1 file changed, 10 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 19a27ac361ef..29a850a8d460 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3718,16 +3718,6 @@ int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb); int netif_rx(struct sk_buff *skb); int __netif_rx(struct sk_buff *skb); -static inline int netif_rx_ni(struct sk_buff *skb) -{ - return netif_rx(skb); -} - -static inline int netif_rx_any_context(struct sk_buff *skb) -{ - return netif_rx(skb); -} - int netif_receive_skb(struct sk_buff *skb); int netif_receive_skb_core(struct sk_buff *skb); void netif_receive_skb_list_internal(struct list_head *head); -- cgit v1.3-14-g43fede From 23c7f8d7989e1646aac82f75761b7648c355cb8a Mon Sep 17 00:00:00 2001 From: Steffen Klassert Date: Mon, 7 Mar 2022 13:11:41 +0100 Subject: net: Fix esp GSO on inter address family tunnels. The esp tunnel GSO handlers use skb_mac_gso_segment to push the inner packet to the segmentation handlers. However, skb_mac_gso_segment takes the Ethernet Protocol ID from 'skb->protocol' which is wrong for inter address family tunnels. We fix this by introducing a new skb_eth_gso_segment function. This function can be used if it is necessary to pass the Ethernet Protocol ID directly to the segmentation handler. First users of this function will be the esp4 and esp6 tunnel segmentation handlers. Fixes: c35fe4106b92 ("xfrm: Add mode handlers for IPsec on layer 2") Signed-off-by: Steffen Klassert --- include/linux/netdevice.h | 2 ++ net/core/gro.c | 25 +++++++++++++++++++++++++ net/ipv4/esp4_offload.c | 3 +-- net/ipv6/esp6_offload.c | 3 +-- 4 files changed, 29 insertions(+), 4 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 8b5a314db167..f53ea7038441 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -4602,6 +4602,8 @@ int skb_csum_hwoffload_help(struct sk_buff *skb, struct sk_buff *__skb_gso_segment(struct sk_buff *skb, netdev_features_t features, bool tx_path); +struct sk_buff *skb_eth_gso_segment(struct sk_buff *skb, + netdev_features_t features, __be16 type); struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb, netdev_features_t features); diff --git a/net/core/gro.c b/net/core/gro.c index a11b286d1495..b7d2b0dc59a2 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -92,6 +92,31 @@ void dev_remove_offload(struct packet_offload *po) } EXPORT_SYMBOL(dev_remove_offload); +/** + * skb_eth_gso_segment - segmentation handler for ethernet protocols. + * @skb: buffer to segment + * @features: features for the output path (see dev->features) + * @type: Ethernet Protocol ID + */ +struct sk_buff *skb_eth_gso_segment(struct sk_buff *skb, + netdev_features_t features, __be16 type) +{ + struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); + struct packet_offload *ptype; + + rcu_read_lock(); + list_for_each_entry_rcu(ptype, &offload_base, list) { + if (ptype->type == type && ptype->callbacks.gso_segment) { + segs = ptype->callbacks.gso_segment(skb, features); + break; + } + } + rcu_read_unlock(); + + return segs; +} +EXPORT_SYMBOL(skb_eth_gso_segment); + /** * skb_mac_gso_segment - mac layer segmentation handler. * @skb: buffer to segment diff --git a/net/ipv4/esp4_offload.c b/net/ipv4/esp4_offload.c index 146d4d54830c..935026f4c807 100644 --- a/net/ipv4/esp4_offload.c +++ b/net/ipv4/esp4_offload.c @@ -110,8 +110,7 @@ static struct sk_buff *xfrm4_tunnel_gso_segment(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features) { - __skb_push(skb, skb->mac_len); - return skb_mac_gso_segment(skb, features); + return skb_eth_gso_segment(skb, features, htons(ETH_P_IP)); } static struct sk_buff *xfrm4_transport_gso_segment(struct xfrm_state *x, diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c index e61172d50817..3a293838a91d 100644 --- a/net/ipv6/esp6_offload.c +++ b/net/ipv6/esp6_offload.c @@ -145,8 +145,7 @@ static struct sk_buff *xfrm6_tunnel_gso_segment(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features) { - __skb_push(skb, skb->mac_len); - return skb_mac_gso_segment(skb, features); + return skb_eth_gso_segment(skb, features, htons(ETH_P_IPV6)); } static struct sk_buff *xfrm6_transport_gso_segment(struct xfrm_state *x, -- cgit v1.3-14-g43fede From 625788b5844511cf4c30cffa7fa0bc3a69cebc82 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 10 Mar 2022 21:14:20 -0800 Subject: net: add per-cpu storage and net->core_stats Before adding yet another possibly contended atomic_long_t, it is time to add per-cpu storage for existing ones: dev->tx_dropped, dev->rx_dropped, and dev->rx_nohandler Because many devices do not have to increment such counters, allocate the per-cpu storage on demand, so that dev_get_stats() does not have to spend considerable time folding zero counters. Note that some drivers have abused these counters which were supposed to be only used by core networking stack. v4: should use per_cpu_ptr() in dev_get_stats() (Jakub) v3: added a READ_ONCE() in netdev_core_stats_alloc() (Paolo) v2: add a missing include (reported by kernel test robot ) Change in netdev_core_stats_alloc() (Jakub) Signed-off-by: Eric Dumazet Cc: jeffreyji Reviewed-by: Brian Vazquez Reviewed-by: Jakub Kicinski Acked-by: Paolo Abeni Link: https://lore.kernel.org/r/20220311051420.2608812-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/bonding/bond_main.c | 2 +- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 4 +- drivers/net/ethernet/hisilicon/hns/hns_ethtool.c | 4 +- .../net/ethernet/qualcomm/rmnet/rmnet_handlers.c | 2 +- drivers/net/ipvlan/ipvlan_core.c | 2 +- drivers/net/macvlan.c | 2 +- drivers/net/net_failover.c | 2 +- drivers/net/tun.c | 16 +++---- drivers/net/vxlan/vxlan_core.c | 2 +- include/linux/netdevice.h | 46 +++++++++++++++---- include/net/bonding.h | 2 +- net/core/dev.c | 51 ++++++++++++++++++---- net/core/gro_cells.c | 2 +- net/hsr/hsr_device.c | 2 +- net/xfrm/xfrm_device.c | 2 +- 15 files changed, 101 insertions(+), 40 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 55e0ba2a163d..15eddca7b4b6 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -5120,7 +5120,7 @@ static netdev_tx_t bond_xmit_broadcast(struct sk_buff *skb, if (xmit_suc) return NETDEV_TX_OK; - atomic_long_inc(&bond_dev->tx_dropped); + dev_core_stats_tx_dropped_inc(bond_dev); return NET_XMIT_DROP; } diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index 2de02950086f..92a1a43b3bee 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -370,7 +370,7 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev) i = skb_get_queue_mapping(skb); if (unlikely(i >= bp->tx_nr_rings)) { dev_kfree_skb_any(skb); - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); return NETDEV_TX_OK; } @@ -646,7 +646,7 @@ tx_kick_pending: if (txr->kick_pending) bnxt_txr_db_kick(bp, txr, txr->tx_prod); txr->tx_buf_ring[txr->tx_prod].skb = NULL; - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); return NETDEV_TX_OK; } diff --git a/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c b/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c index d7a27c244d48..54faf0f2d1d8 100644 --- a/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c +++ b/drivers/net/ethernet/hisilicon/hns/hns_ethtool.c @@ -887,8 +887,8 @@ static void hns_get_ethtool_stats(struct net_device *netdev, p[21] = net_stats->rx_compressed; p[22] = net_stats->tx_compressed; - p[23] = netdev->rx_dropped.counter; - p[24] = netdev->tx_dropped.counter; + p[23] = 0; /* was netdev->rx_dropped.counter */ + p[24] = 0; /* was netdev->tx_dropped.counter */ p[25] = priv->tx_timeout_count; diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c index bfbd7847f946..a313242a762e 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c @@ -207,7 +207,7 @@ rx_handler_result_t rmnet_rx_handler(struct sk_buff **pskb) dev = skb->dev; port = rmnet_get_port_rcu(dev); if (unlikely(!port)) { - atomic_long_inc(&skb->dev->rx_nohandler); + dev_core_stats_rx_nohandler_inc(skb->dev); kfree_skb(skb); goto done; } diff --git a/drivers/net/ipvlan/ipvlan_core.c b/drivers/net/ipvlan/ipvlan_core.c index c613900c3811..6ffb27419e64 100644 --- a/drivers/net/ipvlan/ipvlan_core.c +++ b/drivers/net/ipvlan/ipvlan_core.c @@ -555,7 +555,7 @@ static void ipvlan_multicast_enqueue(struct ipvl_port *port, schedule_work(&port->wq); } else { spin_unlock(&port->backlog.lock); - atomic_long_inc(&skb->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(skb->dev); kfree_skb(skb); } } diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 33753a2fde29..4b77819e9328 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -371,7 +371,7 @@ static void macvlan_broadcast_enqueue(struct macvlan_port *port, free_nskb: kfree_skb(nskb); err: - atomic_long_inc(&skb->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(skb->dev); } static void macvlan_flush_sources(struct macvlan_port *port, diff --git a/drivers/net/net_failover.c b/drivers/net/net_failover.c index 86ec5aae4289..21a0435c02de 100644 --- a/drivers/net/net_failover.c +++ b/drivers/net/net_failover.c @@ -89,7 +89,7 @@ static int net_failover_close(struct net_device *dev) static netdev_tx_t net_failover_drop_xmit(struct sk_buff *skb, struct net_device *dev) { - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); dev_kfree_skb_any(skb); return NETDEV_TX_OK; } diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 2b9a22669a12..276a0e42ca8e 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1135,7 +1135,7 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_OK; drop: - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); skb_tx_error(skb); kfree_skb_reason(skb, drop_reason); rcu_read_unlock(); @@ -1291,7 +1291,7 @@ resample: void *frame = tun_xdp_to_ptr(xdp); if (__ptr_ring_produce(&tfile->tx_ring, frame)) { - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); break; } nxmit++; @@ -1626,7 +1626,7 @@ static int tun_xdp_act(struct tun_struct *tun, struct bpf_prog *xdp_prog, trace_xdp_exception(tun->dev, xdp_prog, act); fallthrough; case XDP_DROP: - atomic_long_inc(&tun->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(tun->dev); break; } @@ -1797,7 +1797,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, */ skb = tun_build_skb(tun, tfile, from, &gso, len, &skb_xdp); if (IS_ERR(skb)) { - atomic_long_inc(&tun->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(tun->dev); return PTR_ERR(skb); } if (!skb) @@ -1826,7 +1826,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (IS_ERR(skb)) { if (PTR_ERR(skb) != -EAGAIN) - atomic_long_inc(&tun->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(tun->dev); if (frags) mutex_unlock(&tfile->napi_mutex); return PTR_ERR(skb); @@ -1841,7 +1841,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, err = -EFAULT; drop_reason = SKB_DROP_REASON_SKB_UCOPY_FAULT; drop: - atomic_long_inc(&tun->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(tun->dev); kfree_skb_reason(skb, drop_reason); if (frags) { tfile->napi.skb = NULL; @@ -1876,7 +1876,7 @@ drop: pi.proto = htons(ETH_P_IPV6); break; default: - atomic_long_inc(&tun->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(tun->dev); kfree_skb(skb); return -EINVAL; } @@ -1956,7 +1956,7 @@ drop: skb_headlen(skb)); if (unlikely(headlen > skb_headlen(skb))) { - atomic_long_inc(&tun->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(tun->dev); napi_free_frags(&tfile->napi); rcu_read_unlock(); mutex_unlock(&tfile->napi_mutex); diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c index 3872f76ea1d3..de97ff98d36e 100644 --- a/drivers/net/vxlan/vxlan_core.c +++ b/drivers/net/vxlan/vxlan_core.c @@ -1760,7 +1760,7 @@ static int vxlan_rcv(struct sock *sk, struct sk_buff *skb) if (unlikely(!(vxlan->dev->flags & IFF_UP))) { rcu_read_unlock(); - atomic_long_inc(&vxlan->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(vxlan->dev); vxlan_vnifilter_count(vxlan, vni, vninode, VXLAN_VNI_STATS_RX_DROPS, 0); goto drop; diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index acd3cf69b61f..0d994710b335 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -194,6 +195,14 @@ struct net_device_stats { unsigned long tx_compressed; }; +/* per-cpu stats, allocated on demand. + * Try to fit them in a single cache line, for dev_get_stats() sake. + */ +struct net_device_core_stats { + local_t rx_dropped; + local_t tx_dropped; + local_t rx_nohandler; +} __aligned(4 * sizeof(local_t)); #include #include @@ -1735,12 +1744,8 @@ enum netdev_ml_priv_type { * @stats: Statistics struct, which was left as a legacy, use * rtnl_link_stats64 instead * - * @rx_dropped: Dropped packets by core network, - * do not use this in drivers - * @tx_dropped: Dropped packets by core network, + * @core_stats: core networking counters, * do not use this in drivers - * @rx_nohandler: nohandler dropped packets by core network on - * inactive devices, do not use this in drivers * @carrier_up_count: Number of times the carrier has been up * @carrier_down_count: Number of times the carrier has been down * @@ -2023,9 +2028,7 @@ struct net_device { struct net_device_stats stats; /* not used by modern drivers */ - atomic_long_t rx_dropped; - atomic_long_t tx_dropped; - atomic_long_t rx_nohandler; + struct net_device_core_stats __percpu *core_stats; /* Stats to monitor link on/off, flapping */ atomic_t carrier_up_count; @@ -3839,13 +3842,38 @@ static __always_inline bool __is_skb_forwardable(const struct net_device *dev, return false; } +struct net_device_core_stats *netdev_core_stats_alloc(struct net_device *dev); + +static inline struct net_device_core_stats *dev_core_stats(struct net_device *dev) +{ + /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ + struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats); + + if (likely(p)) + return this_cpu_ptr(p); + + return netdev_core_stats_alloc(dev); +} + +#define DEV_CORE_STATS_INC(FIELD) \ +static inline void dev_core_stats_##FIELD##_inc(struct net_device *dev) \ +{ \ + struct net_device_core_stats *p = dev_core_stats(dev); \ + \ + if (p) \ + local_inc(&p->FIELD); \ +} +DEV_CORE_STATS_INC(rx_dropped) +DEV_CORE_STATS_INC(tx_dropped) +DEV_CORE_STATS_INC(rx_nohandler) + static __always_inline int ____dev_forward_skb(struct net_device *dev, struct sk_buff *skb, const bool check_mtu) { if (skb_orphan_frags(skb, GFP_ATOMIC) || unlikely(!__is_skb_forwardable(dev, skb, check_mtu))) { - atomic_long_inc(&dev->rx_dropped); + dev_core_stats_rx_dropped_inc(dev); kfree_skb(skb); return NET_RX_DROP; } diff --git a/include/net/bonding.h b/include/net/bonding.h index d0dfe727e0b1..b14f4c0b4e9e 100644 --- a/include/net/bonding.h +++ b/include/net/bonding.h @@ -770,7 +770,7 @@ extern const struct sysfs_ops slave_sysfs_ops; static inline netdev_tx_t bond_tx_drop(struct net_device *dev, struct sk_buff *skb) { - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); dev_kfree_skb_any(skb); return NET_XMIT_DROP; } diff --git a/net/core/dev.c b/net/core/dev.c index 7ed27c178a1f..8d25ec5b3af7 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3633,7 +3633,7 @@ static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device out_kfree_skb: kfree_skb(skb); out_null: - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); return NULL; } @@ -4184,7 +4184,7 @@ recursion_alert: rc = -ENETDOWN; rcu_read_unlock_bh(); - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); kfree_skb_list(skb); return rc; out: @@ -4236,7 +4236,7 @@ int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id) local_bh_enable(); return ret; drop: - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); kfree_skb_list(skb); return NET_XMIT_DROP; } @@ -4602,7 +4602,7 @@ drop: sd->dropped++; rps_unlock_irq_restore(sd, &flags); - atomic_long_inc(&skb->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(skb->dev); kfree_skb_reason(skb, reason); return NET_RX_DROP; } @@ -5357,10 +5357,10 @@ check_vlan_id: } else { drop: if (!deliver_exact) { - atomic_long_inc(&skb->dev->rx_dropped); + dev_core_stats_rx_dropped_inc(skb->dev); kfree_skb_reason(skb, SKB_DROP_REASON_PTYPE_ABSENT); } else { - atomic_long_inc(&skb->dev->rx_nohandler); + dev_core_stats_rx_nohandler_inc(skb->dev); kfree_skb(skb); } /* Jamal, now you will not able to escape explaining @@ -10280,6 +10280,25 @@ void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, } EXPORT_SYMBOL(netdev_stats_to_stats64); +struct net_device_core_stats *netdev_core_stats_alloc(struct net_device *dev) +{ + struct net_device_core_stats __percpu *p; + + p = alloc_percpu_gfp(struct net_device_core_stats, + GFP_ATOMIC | __GFP_NOWARN); + + if (p && cmpxchg(&dev->core_stats, NULL, p)) + free_percpu(p); + + /* This READ_ONCE() pairs with the cmpxchg() above */ + p = READ_ONCE(dev->core_stats); + if (!p) + return NULL; + + return this_cpu_ptr(p); +} +EXPORT_SYMBOL(netdev_core_stats_alloc); + /** * dev_get_stats - get network device statistics * @dev: device to get statistics from @@ -10294,6 +10313,7 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, struct rtnl_link_stats64 *storage) { const struct net_device_ops *ops = dev->netdev_ops; + const struct net_device_core_stats __percpu *p; if (ops->ndo_get_stats64) { memset(storage, 0, sizeof(*storage)); @@ -10303,9 +10323,20 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, } else { netdev_stats_to_stats64(storage, &dev->stats); } - storage->rx_dropped += (unsigned long)atomic_long_read(&dev->rx_dropped); - storage->tx_dropped += (unsigned long)atomic_long_read(&dev->tx_dropped); - storage->rx_nohandler += (unsigned long)atomic_long_read(&dev->rx_nohandler); + + /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ + p = READ_ONCE(dev->core_stats); + if (p) { + const struct net_device_core_stats *core_stats; + int i; + + for_each_possible_cpu(i) { + core_stats = per_cpu_ptr(p, i); + storage->rx_dropped += local_read(&core_stats->rx_dropped); + storage->tx_dropped += local_read(&core_stats->tx_dropped); + storage->rx_nohandler += local_read(&core_stats->rx_nohandler); + } + } return storage; } EXPORT_SYMBOL(dev_get_stats); @@ -10567,6 +10598,8 @@ void free_netdev(struct net_device *dev) free_percpu(dev->pcpu_refcnt); dev->pcpu_refcnt = NULL; #endif + free_percpu(dev->core_stats); + dev->core_stats = NULL; free_percpu(dev->xdp_bulkq); dev->xdp_bulkq = NULL; diff --git a/net/core/gro_cells.c b/net/core/gro_cells.c index 8462f926ab45..541c7a72a28a 100644 --- a/net/core/gro_cells.c +++ b/net/core/gro_cells.c @@ -28,7 +28,7 @@ int gro_cells_receive(struct gro_cells *gcells, struct sk_buff *skb) if (skb_queue_len(&cell->napi_skbs) > netdev_max_backlog) { drop: - atomic_long_inc(&dev->rx_dropped); + dev_core_stats_rx_dropped_inc(dev); kfree_skb(skb); res = NET_RX_DROP; goto unlock; diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c index 7f250216433d..6ffef47e9be5 100644 --- a/net/hsr/hsr_device.c +++ b/net/hsr/hsr_device.c @@ -221,7 +221,7 @@ static netdev_tx_t hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev) skb_reset_mac_len(skb); hsr_forward_skb(skb, master); } else { - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); dev_kfree_skb_any(skb); } return NETDEV_TX_OK; diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c index 39bce5d764de..3e3448ada1bb 100644 --- a/net/xfrm/xfrm_device.c +++ b/net/xfrm/xfrm_device.c @@ -143,7 +143,7 @@ struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t featur segs = skb_gso_segment(skb, esp_features); if (IS_ERR(segs)) { kfree_skb(skb); - atomic_long_inc(&dev->tx_dropped); + dev_core_stats_tx_dropped_inc(dev); return NULL; } else { consume_skb(skb); -- cgit v1.3-14-g43fede From fc93db153b0187a9047f00bfd5cce75108530593 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 12 Mar 2022 13:45:05 -0800 Subject: net: disable preemption in dev_core_stats_XXX_inc() helpers syzbot was kind enough to remind us that dev->{tx_dropped|rx_dropped} could be increased in process context. BUG: using smp_processor_id() in preemptible [00000000] code: syz-executor413/3593 caller is netdev_core_stats_alloc+0x98/0x110 net/core/dev.c:10298 CPU: 1 PID: 3593 Comm: syz-executor413 Not tainted 5.17.0-rc7-syzkaller-02426-g97aeb877de7f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 check_preemption_disabled+0x16b/0x170 lib/smp_processor_id.c:49 netdev_core_stats_alloc+0x98/0x110 net/core/dev.c:10298 dev_core_stats include/linux/netdevice.h:3855 [inline] dev_core_stats_rx_dropped_inc include/linux/netdevice.h:3866 [inline] tun_get_user+0x3455/0x3ab0 drivers/net/tun.c:1800 tun_chr_write_iter+0xe1/0x200 drivers/net/tun.c:2015 call_write_iter include/linux/fs.h:2074 [inline] new_sync_write+0x431/0x660 fs/read_write.c:503 vfs_write+0x7cd/0xae0 fs/read_write.c:590 ksys_write+0x12d/0x250 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f2cf4f887e3 Code: 5d 41 5c 41 5d 41 5e e9 9b fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 55 c3 0f 1f 40 00 48 83 ec 28 48 89 54 24 18 RSP: 002b:00007ffd50dd5fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007ffd50dd6000 RCX: 00007f2cf4f887e3 RDX: 000000000000002a RSI: 0000000000000000 RDI: 00000000000000c8 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd50dd5ff0 R14: 00007ffd50dd5fe8 R15: 00007ffd50dd5fe4 Fixes: 625788b58445 ("net: add per-cpu storage and net->core_stats") Signed-off-by: Eric Dumazet Cc: jeffreyji Cc: Brian Vazquez Acked-by: Paolo Abeni Link: https://lore.kernel.org/r/20220312214505.3294762-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski --- include/linux/netdevice.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 0d994710b335..8cbe96ce0a2c 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3858,10 +3858,14 @@ static inline struct net_device_core_stats *dev_core_stats(struct net_device *de #define DEV_CORE_STATS_INC(FIELD) \ static inline void dev_core_stats_##FIELD##_inc(struct net_device *dev) \ { \ - struct net_device_core_stats *p = dev_core_stats(dev); \ + struct net_device_core_stats *p; \ + \ + preempt_disable(); \ + p = dev_core_stats(dev); \ \ if (p) \ local_inc(&p->FIELD); \ + preempt_enable(); \ } DEV_CORE_STATS_INC(rx_dropped) DEV_CORE_STATS_INC(tx_dropped) -- cgit v1.3-14-g43fede From 046e1537a3cf0adc68fe865b5dc9a7e731cc63b3 Mon Sep 17 00:00:00 2001 From: Íñigo Huguet Date: Tue, 15 Mar 2022 10:18:32 +0100 Subject: net: set default rss queues num to physical cores / 2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Network drivers can call to netif_get_num_default_rss_queues to get the default number of receive queues to use. Right now, this default number is min(8, num_online_cpus()). Instead, as suggested by Jakub, use the number of physical cores divided by 2 as a way to avoid wasting CPU resources and to avoid using both CPU threads, but still allowing to scale for high-end processors with many cores. As an exception, select 2 queues for processors with 2 cores, because otherwise it won't take any advantage of RSS despite being SMP capable. Tested: Processor Intel Xeon E5-2620 (2 sockets, 6 cores/socket, 2 threads/core). NIC Broadcom NetXtreme II BCM57810 (10GBps). Ran some tests with `perf stat iperf3 -R`, with parallelisms of 1, 8 and 24, getting the following results: - Number of queues: 6 (instead of 8) - Network throughput: not affected - CPU usage: utilized 0.05-0.12 CPUs more than before (having 24 CPUs this is only 0.2-0.5% higher) - Reduced the number of context switches by 7-50%, being more noticeable when using a higher number of parallel threads. Suggested-by: Jakub Kicinski Signed-off-by: Íñigo Huguet Link: https://lore.kernel.org/r/20220315091832.13873-1-ihuguet@redhat.com Signed-off-by: Jakub Kicinski --- include/linux/netdevice.h | 1 - net/core/dev.c | 20 ++++++++++++++++---- 2 files changed, 16 insertions(+), 5 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 8cbe96ce0a2c..e01a8ce7181f 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -3664,7 +3664,6 @@ static inline unsigned int get_netdev_rx_queue_index( } #endif -#define DEFAULT_MAX_NUM_RSS_QUEUES (8) int netif_get_num_default_rss_queues(void); enum skb_free_reason { diff --git a/net/core/dev.c b/net/core/dev.c index 75bab5b0dbae..8e0cc5f2020d 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2990,13 +2990,25 @@ EXPORT_SYMBOL(netif_set_real_num_queues); /** * netif_get_num_default_rss_queues - default number of RSS queues * - * This routine should set an upper limit on the number of RSS queues - * used by default by multiqueue devices. + * Default value is the number of physical cores if there are only 1 or 2, or + * divided by 2 if there are more. */ int netif_get_num_default_rss_queues(void) { - return is_kdump_kernel() ? - 1 : min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus()); + cpumask_var_t cpus; + int cpu, count = 0; + + if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL))) + return 1; + + cpumask_copy(cpus, cpu_online_mask); + for_each_cpu(cpu, cpus) { + ++count; + cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu)); + } + free_cpumask_var(cpus); + + return count > 2 ? DIV_ROUND_UP(count, 2) : count; } EXPORT_SYMBOL(netif_get_num_default_rss_queues); -- cgit v1.3-14-g43fede From 4a0cb83ba6e0cd73a50fa4f84736846bf0029f2b Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 21 Mar 2022 22:10:53 -0700 Subject: netdevice: add missing dm_private kdoc Building htmldocs complains: include/linux/netdevice.h:2295: warning: Function parameter or member 'dm_private' not described in 'net_device' Fixes: b26ef81c46ed ("drop_monitor: remove quadratic behavior") Signed-off-by: Jakub Kicinski Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/20220322051053.1883186-1-kuba@kernel.org Signed-off-by: Paolo Abeni --- include/linux/netdevice.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index e01a8ce7181f..cd7a597c55b1 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1899,6 +1899,8 @@ enum netdev_ml_priv_type { * @garp_port: GARP * @mrp_port: MRP * + * @dm_private: Drop monitor private + * * @dev: Class/net/name entry * @sysfs_groups: Space for optional device, statistics and wireless * sysfs groups -- cgit v1.3-14-g43fede From f32404ae1bb9a7428a3c77419672a28895d185bf Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 25 Mar 2022 22:50:23 +0100 Subject: net: move net_unlink_todo() out of the header There's no reason for this to be in netdevice.h, it's all just used in dev.c. Also make it no longer inline and let the compiler decide to do that by itself. Signed-off-by: Johannes Berg Link: https://lore.kernel.org/r/20220325225023.f49b9056fe1c.I6b901a2df00000837a9bd251a8dd259bd23f5ded@changeid Signed-off-by: Jakub Kicinski --- include/linux/netdevice.h | 10 ---------- net/core/dev.c | 10 ++++++++++ 2 files changed, 10 insertions(+), 10 deletions(-) (limited to 'include/linux/netdevice.h') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index cd7a597c55b1..59e27a2b7bf0 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -4601,16 +4601,6 @@ bool netdev_has_upper_dev(struct net_device *dev, struct net_device *upper_dev); struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, struct list_head **iter); -#ifdef CONFIG_LOCKDEP -static LIST_HEAD(net_unlink_list); - -static inline void net_unlink_todo(struct net_device *dev) -{ - if (list_empty(&dev->unlink_list)) - list_add_tail(&dev->unlink_list, &net_unlink_list); -} -#endif - /* iterate through upper list, must be called under RCU read lock */ #define netdev_for_each_upper_dev_rcu(dev, updev, iter) \ for (iter = &(dev)->adj_list.upper, \ diff --git a/net/core/dev.c b/net/core/dev.c index 8a5109479dbe..8c6c08446556 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -7193,6 +7193,16 @@ static int __netdev_update_upper_level(struct net_device *dev, return 0; } +#ifdef CONFIG_LOCKDEP +static LIST_HEAD(net_unlink_list); + +static void net_unlink_todo(struct net_device *dev) +{ + if (list_empty(&dev->unlink_list)) + list_add_tail(&dev->unlink_list, &net_unlink_list); +} +#endif + static int __netdev_update_lower_level(struct net_device *dev, struct netdev_nested_priv *priv) { -- cgit v1.3-14-g43fede