From: Florian Westphal fw@strlen.de
commit 97cdcf37b57e3f204be3000b9eab9686f38b4356 upstream.
This fills a hole in softnet data, so no change in structure size.
Also prepares for xmit_more placement in the same spot; skb->xmit_more will be removed in followup patch.
Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/linux/netdevice.h | 40 +++++++++++++++++++++++++++++++-------- net/core/dev.c | 10 +++------- net/core/filter.c | 6 +++--- 3 files changed, 38 insertions(+), 18 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 84bbdcbb199a9..41beebcc61f45 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2620,14 +2620,6 @@ void netdev_freemem(struct net_device *dev); void synchronize_net(void); int init_dummy_netdev(struct net_device *dev);
-DECLARE_PER_CPU(int, xmit_recursion); -#define XMIT_RECURSION_LIMIT 10 - -static inline int dev_recursion_level(void) -{ - return this_cpu_read(xmit_recursion); -} - struct net_device *dev_get_by_index(struct net *net, int ifindex); struct net_device *__dev_get_by_index(struct net *net, int ifindex); struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex); @@ -2967,6 +2959,11 @@ struct softnet_data { #ifdef CONFIG_XFRM_OFFLOAD struct sk_buff_head xfrm_backlog; #endif + /* written and read only by owning cpu: */ + struct { + u16 recursion; + u8 more; + } xmit; #ifdef CONFIG_RPS /* input_queue_head should be written by cpu owning this struct, * and only read by other cpus. Worth using a cache line. @@ -3002,6 +2999,28 @@ static inline void input_queue_tail_incr_save(struct softnet_data *sd,
DECLARE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
+static inline int dev_recursion_level(void) +{ + return __this_cpu_read(softnet_data.xmit.recursion); +} + +#define XMIT_RECURSION_LIMIT 10 +static inline bool dev_xmit_recursion(void) +{ + return unlikely(__this_cpu_read(softnet_data.xmit.recursion) > + XMIT_RECURSION_LIMIT); +} + +static inline void dev_xmit_recursion_inc(void) +{ + __this_cpu_inc(softnet_data.xmit.recursion); +} + +static inline void dev_xmit_recursion_dec(void) +{ + __this_cpu_dec(softnet_data.xmit.recursion); +} + void __netif_schedule(struct Qdisc *q); void netif_schedule_queue(struct netdev_queue *txq);
@@ -4314,6 +4333,11 @@ static inline netdev_tx_t __netdev_start_xmit(const struct net_device_ops *ops, return ops->ndo_start_xmit(skb, dev); }
+static inline bool netdev_xmit_more(void) +{ + return __this_cpu_read(softnet_data.xmit.more); +} + static inline netdev_tx_t netdev_start_xmit(struct sk_buff *skb, struct net_device *dev, struct netdev_queue *txq, bool more) { diff --git a/net/core/dev.c b/net/core/dev.c index 5e668d3b1e717..8f9a8b009a238 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3534,9 +3534,6 @@ static void skb_update_prio(struct sk_buff *skb) #define skb_update_prio(skb) #endif
-DEFINE_PER_CPU(int, xmit_recursion); -EXPORT_SYMBOL(xmit_recursion); - /** * dev_loopback_xmit - loop back @skb * @net: network namespace this loopback is happening in @@ -3827,8 +3824,7 @@ static int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) int cpu = smp_processor_id(); /* ok because BHs are off */
if (txq->xmit_lock_owner != cpu) { - if (unlikely(__this_cpu_read(xmit_recursion) > - XMIT_RECURSION_LIMIT)) + if (dev_xmit_recursion()) goto recursion_alert;
skb = validate_xmit_skb(skb, dev, &again); @@ -3838,9 +3834,9 @@ static int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) HARD_TX_LOCK(dev, txq, cpu);
if (!netif_xmit_stopped(txq)) { - __this_cpu_inc(xmit_recursion); + dev_xmit_recursion_inc(); skb = dev_hard_start_xmit(skb, dev, txq, &rc); - __this_cpu_dec(xmit_recursion); + dev_xmit_recursion_dec(); if (dev_xmit_complete(rc)) { HARD_TX_UNLOCK(dev, txq); goto out; diff --git a/net/core/filter.c b/net/core/filter.c index b5521b60a2d4f..636e67a928477 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2002,7 +2002,7 @@ static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb) { int ret;
- if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) { + if (dev_xmit_recursion()) { net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n"); kfree_skb(skb); return -ENETDOWN; @@ -2011,9 +2011,9 @@ static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb) skb->dev = dev; skb->tstamp = 0;
- __this_cpu_inc(xmit_recursion); + dev_xmit_recursion_inc(); ret = dev_queue_xmit(skb); - __this_cpu_dec(xmit_recursion); + dev_xmit_recursion_dec();
return ret; }