From e1bd4d3d7dd2a4a0e731ffe07c439927c23f16ea Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Fri, 14 Mar 2014 20:50:58 -0700 Subject: [PATCH] netpoll: Move all receive processing under CONFIG_NETPOLL_TRAP Make rx_skb_hook, and rx in struct netpoll depend on CONFIG_NETPOLL_TRAP Make rx_lock, rx_np, and neigh_tx in struct netpoll_info depend on CONFIG_NETPOLL_TRAP Make the functions netpoll_rx_on, netpoll_rx, and netpoll_receive_skb no-ops when CONFIG_NETPOLL_TRAP is not set. Only build netpoll_neigh_reply, checksum_udp service_neigh_queue, pkt_is_ns, and __netpoll_rx when CONFIG_NETPOLL_TRAP is defined. Add helper functions netpoll_trap_setup, netpoll_trap_setup_info, netpoll_trap_cleanup, and netpoll_trap_cleanup_info that initialize and cleanup the struct netpoll and struct netpoll_info receive specific fields when CONFIG_NETPOLL_TRAP is enabled and do nothing otherwise. Signed-off-by: "Eric W. Biederman" Signed-off-by: David S. Miller --- include/linux/netpoll.h | 73 ++++++++++++++++++++----------------- net/core/netpoll.c | 81 ++++++++++++++++++++++++++++++++--------- 2 files changed, 104 insertions(+), 50 deletions(-) diff --git a/include/linux/netpoll.h b/include/linux/netpoll.h index ab9aaaff8d04..a0632af88d8b 100644 --- a/include/linux/netpoll.h +++ b/include/linux/netpoll.h @@ -24,32 +24,38 @@ struct netpoll { struct net_device *dev; char dev_name[IFNAMSIZ]; const char *name; - void (*rx_skb_hook)(struct netpoll *np, int source, struct sk_buff *skb, - int offset, int len); union inet_addr local_ip, remote_ip; bool ipv6; u16 local_port, remote_port; u8 remote_mac[ETH_ALEN]; - struct list_head rx; /* rx_np list element */ struct work_struct cleanup_work; + +#ifdef CONFIG_NETPOLL_TRAP + void (*rx_skb_hook)(struct netpoll *np, int source, struct sk_buff *skb, + int offset, int len); + struct list_head rx; /* rx_np list element */ +#endif }; struct netpoll_info { atomic_t refcnt; - spinlock_t rx_lock; struct semaphore dev_lock; - struct list_head rx_np; /* netpolls that registered an rx_skb_hook */ - struct sk_buff_head neigh_tx; /* list of neigh requests to reply to */ struct sk_buff_head txq; struct delayed_work tx_work; struct netpoll *netpoll; struct rcu_head rcu; + +#ifdef CONFIG_NETPOLL_TRAP + spinlock_t rx_lock; + struct list_head rx_np; /* netpolls that registered an rx_skb_hook */ + struct sk_buff_head neigh_tx; /* list of neigh requests to reply to */ +#endif }; #ifdef CONFIG_NETPOLL @@ -68,7 +74,6 @@ int netpoll_setup(struct netpoll *np); void __netpoll_cleanup(struct netpoll *np); void __netpoll_free_async(struct netpoll *np); void netpoll_cleanup(struct netpoll *np); -int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo); void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb, struct net_device *dev); static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) @@ -82,25 +87,12 @@ static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) #ifdef CONFIG_NETPOLL_TRAP int netpoll_trap(void); void netpoll_set_trap(int trap); +int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo); static inline bool netpoll_rx_processing(struct netpoll_info *npinfo) { return !list_empty(&npinfo->rx_np); } -#else -static inline int netpoll_trap(void) -{ - return 0; -} -static inline void netpoll_set_trap(int trap) -{ -} -static inline bool netpoll_rx_processing(struct netpoll_info *npinfo) -{ - return false; -} -#endif -#ifdef CONFIG_NETPOLL static inline bool netpoll_rx_on(struct sk_buff *skb) { struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo); @@ -138,6 +130,33 @@ static inline int netpoll_receive_skb(struct sk_buff *skb) return 0; } +#else +static inline int netpoll_trap(void) +{ + return 0; +} +static inline void netpoll_set_trap(int trap) +{ +} +static inline bool netpoll_rx_processing(struct netpoll_info *npinfo) +{ + return false; +} +static inline bool netpoll_rx(struct sk_buff *skb) +{ + return false; +} +static inline bool netpoll_rx_on(struct sk_buff *skb) +{ + return false; +} +static inline int netpoll_receive_skb(struct sk_buff *skb) +{ + return 0; +} +#endif + +#ifdef CONFIG_NETPOLL static inline void *netpoll_poll_lock(struct napi_struct *napi) { struct net_device *dev = napi->dev; @@ -166,18 +185,6 @@ static inline bool netpoll_tx_running(struct net_device *dev) } #else -static inline bool netpoll_rx(struct sk_buff *skb) -{ - return false; -} -static inline bool netpoll_rx_on(struct sk_buff *skb) -{ - return false; -} -static inline int netpoll_receive_skb(struct sk_buff *skb) -{ - return 0; -} static inline void *netpoll_poll_lock(struct napi_struct *napi) { return NULL; diff --git a/net/core/netpoll.c b/net/core/netpoll.c index b69bb3f1ba3f..eed8b1d2d302 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -48,6 +48,7 @@ static struct sk_buff_head skb_pool; #ifdef CONFIG_NETPOLL_TRAP static atomic_t trapped; +static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo); #endif DEFINE_STATIC_SRCU(netpoll_srcu); @@ -61,7 +62,6 @@ DEFINE_STATIC_SRCU(netpoll_srcu); MAX_UDP_CHUNK) static void zap_completion_queue(void); -static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo); static void netpoll_async_cleanup(struct work_struct *work); static unsigned int carrier_timeout = 4; @@ -109,6 +109,7 @@ static void queue_process(struct work_struct *work) } } +#ifdef CONFIG_NETPOLL_TRAP static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh, unsigned short ulen, __be32 saddr, __be32 daddr) { @@ -127,6 +128,7 @@ static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh, return __skb_checksum_complete(skb); } +#endif /* CONFIG_NETPOLL_TRAP */ /* * Check whether delayed processing was scheduled for our NIC. If so, @@ -179,6 +181,7 @@ static void poll_napi(struct net_device *dev, int budget) } } +#ifdef CONFIG_NETPOLL_TRAP static void service_neigh_queue(struct net_device *dev, struct netpoll_info *npi) { @@ -197,6 +200,12 @@ static void service_neigh_queue(struct net_device *dev, while ((skb = skb_dequeue(&npi->neigh_tx))) netpoll_neigh_reply(skb, npi); } +#else /* !CONFIG_NETPOLL_TRAP */ +static inline void service_neigh_queue(struct net_device *dev, + struct netpoll_info *npi) +{ +} +#endif /* CONFIG_NETPOLL_TRAP */ static void netpoll_poll_dev(struct net_device *dev) { @@ -522,6 +531,7 @@ void netpoll_send_udp(struct netpoll *np, const char *msg, int len) } EXPORT_SYMBOL(netpoll_send_udp); +#ifdef CONFIG_NETPOLL_TRAP static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo) { int size, type = ARPOP_REPLY; @@ -900,6 +910,55 @@ out: return 0; } +static void netpoll_trap_setup_info(struct netpoll_info *npinfo) +{ + INIT_LIST_HEAD(&npinfo->rx_np); + spin_lock_init(&npinfo->rx_lock); + skb_queue_head_init(&npinfo->neigh_tx); +} + +static void netpoll_trap_cleanup_info(struct netpoll_info *npinfo) +{ + skb_queue_purge(&npinfo->neigh_tx); +} + +static void netpoll_trap_setup(struct netpoll *np, struct netpoll_info *npinfo) +{ + unsigned long flags; + if (np->rx_skb_hook) { + spin_lock_irqsave(&npinfo->rx_lock, flags); + list_add_tail(&np->rx, &npinfo->rx_np); + spin_unlock_irqrestore(&npinfo->rx_lock, flags); + } +} + +static void netpoll_trap_cleanup(struct netpoll *np, struct netpoll_info *npinfo) +{ + unsigned long flags; + if (!list_empty(&npinfo->rx_np)) { + spin_lock_irqsave(&npinfo->rx_lock, flags); + list_del(&np->rx); + spin_unlock_irqrestore(&npinfo->rx_lock, flags); + } +} + +#else /* !CONFIG_NETPOLL_TRAP */ +static inline void netpoll_trap_setup_info(struct netpoll_info *npinfo) +{ +} +static inline void netpoll_trap_cleanup_info(struct netpoll_info *npinfo) +{ +} +static inline +void netpoll_trap_setup(struct netpoll *np, struct netpoll_info *npinfo) +{ +} +static inline +void netpoll_trap_cleanup(struct netpoll *np, struct netpoll_info *npinfo) +{ +} +#endif /* CONFIG_NETPOLL_TRAP */ + void netpoll_print_options(struct netpoll *np) { np_info(np, "local port %d\n", np->local_port); @@ -1023,7 +1082,6 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp) { struct netpoll_info *npinfo; const struct net_device_ops *ops; - unsigned long flags; int err; np->dev = ndev; @@ -1045,11 +1103,9 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp) goto out; } - INIT_LIST_HEAD(&npinfo->rx_np); + netpoll_trap_setup_info(npinfo); - spin_lock_init(&npinfo->rx_lock); sema_init(&npinfo->dev_lock, 1); - skb_queue_head_init(&npinfo->neigh_tx); skb_queue_head_init(&npinfo->txq); INIT_DELAYED_WORK(&npinfo->tx_work, queue_process); @@ -1068,11 +1124,7 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp) npinfo->netpoll = np; - if (np->rx_skb_hook) { - spin_lock_irqsave(&npinfo->rx_lock, flags); - list_add_tail(&np->rx, &npinfo->rx_np); - spin_unlock_irqrestore(&npinfo->rx_lock, flags); - } + netpoll_trap_setup(np, npinfo); /* last thing to do is link it to the net device structure */ rcu_assign_pointer(ndev->npinfo, npinfo); @@ -1222,7 +1274,7 @@ static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head) struct netpoll_info *npinfo = container_of(rcu_head, struct netpoll_info, rcu); - skb_queue_purge(&npinfo->neigh_tx); + netpoll_trap_cleanup_info(npinfo); skb_queue_purge(&npinfo->txq); /* we can't call cancel_delayed_work_sync here, as we are in softirq */ @@ -1238,7 +1290,6 @@ static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head) void __netpoll_cleanup(struct netpoll *np) { struct netpoll_info *npinfo; - unsigned long flags; /* rtnl_dereference would be preferable here but * rcu_cleanup_netpoll path can put us in here safely without @@ -1248,11 +1299,7 @@ void __netpoll_cleanup(struct netpoll *np) if (!npinfo) return; - if (!list_empty(&npinfo->rx_np)) { - spin_lock_irqsave(&npinfo->rx_lock, flags); - list_del(&np->rx); - spin_unlock_irqrestore(&npinfo->rx_lock, flags); - } + netpoll_trap_cleanup(np, npinfo); synchronize_srcu(&netpoll_srcu); -- 2.20.1