diff options
| -rw-r--r-- | include/linux/netdevice.h | 13 | ||||
| -rw-r--r-- | net/Kconfig | 8 | ||||
| -rw-r--r-- | net/core/dev.c | 10 |
3 files changed, 31 insertions, 0 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 4940509999be..8f003955c485 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2092,7 +2092,12 @@ struct net_device { u32 proto_down_reason; struct list_head todo_list; + +#ifdef CONFIG_PCPU_DEV_REFCNT int __percpu *pcpu_refcnt; +#else + refcount_t dev_refcnt; +#endif struct list_head link_watch_list; @@ -4044,7 +4049,11 @@ void netdev_run_todo(void); */ static inline void dev_put(struct net_device *dev) { +#ifdef CONFIG_PCPU_DEV_REFCNT this_cpu_dec(*dev->pcpu_refcnt); +#else + refcount_dec(&dev->dev_refcnt); +#endif } /** @@ -4055,7 +4064,11 @@ static inline void dev_put(struct net_device *dev) */ static inline void dev_hold(struct net_device *dev) { +#ifdef CONFIG_PCPU_DEV_REFCNT this_cpu_inc(*dev->pcpu_refcnt); +#else + refcount_inc(&dev->dev_refcnt); +#endif } /* Carrier loss detection, dial on demand. The functions netif_carrier_on diff --git a/net/Kconfig b/net/Kconfig index 0ead7ec0d2bd..9c456acc379e 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -245,6 +245,14 @@ source "net/l3mdev/Kconfig" source "net/qrtr/Kconfig" source "net/ncsi/Kconfig" +config PCPU_DEV_REFCNT + bool "Use percpu variables to maintain network device refcount" + depends on SMP + default y + help + network device refcount are using per cpu variables if this option is set. + This can be forced to N to detect underflows (with a performance drop). + config RPS bool depends on SMP && SYSFS diff --git a/net/core/dev.c b/net/core/dev.c index 4961fc2e9b19..be941ed754ac 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10312,11 +10312,15 @@ EXPORT_SYMBOL(register_netdev); int netdev_refcnt_read(const struct net_device *dev) { +#ifdef CONFIG_PCPU_DEV_REFCNT int i, refcnt = 0; for_each_possible_cpu(i) refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); return refcnt; +#else + return refcount_read(&dev->dev_refcnt); +#endif } EXPORT_SYMBOL(netdev_refcnt_read); @@ -10674,9 +10678,11 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, dev = PTR_ALIGN(p, NETDEV_ALIGN); dev->padded = (char *)dev - (char *)p; +#ifdef CONFIG_PCPU_DEV_REFCNT dev->pcpu_refcnt = alloc_percpu(int); if (!dev->pcpu_refcnt) goto free_dev; +#endif if (dev_addr_init(dev)) goto free_pcpu; @@ -10740,8 +10746,10 @@ free_all: return NULL; free_pcpu: +#ifdef CONFIG_PCPU_DEV_REFCNT free_percpu(dev->pcpu_refcnt); free_dev: +#endif netdev_freemem(dev); return NULL; } @@ -10783,8 +10791,10 @@ void free_netdev(struct net_device *dev) list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) netif_napi_del(p); +#ifdef CONFIG_PCPU_DEV_REFCNT free_percpu(dev->pcpu_refcnt); dev->pcpu_refcnt = NULL; +#endif free_percpu(dev->xdp_bulkq); dev->xdp_bulkq = NULL; |