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" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netpoll.h b/include/linux/netpoll.h
index ab9aaaf..a0632af 100644
--- a/include/linux/netpoll.h
+++ b/include/linux/netpoll.h
@@ -24,32 +24,38 @@
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 @@
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 @@
#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 @@
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 @@
}
#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 b69bb3f..eed8b1d 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -48,6 +48,7 @@
#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 @@
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 @@
}
}
+#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 @@
return __skb_checksum_complete(skb);
}
+#endif /* CONFIG_NETPOLL_TRAP */
/*
* Check whether delayed processing was scheduled for our NIC. If so,
@@ -179,6 +181,7 @@
}
}
+#ifdef CONFIG_NETPOLL_TRAP
static void service_neigh_queue(struct net_device *dev,
struct netpoll_info *npi)
{
@@ -197,6 +200,12 @@
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 @@
}
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 @@
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 @@
{
struct netpoll_info *npinfo;
const struct net_device_ops *ops;
- unsigned long flags;
int err;
np->dev = ndev;
@@ -1045,11 +1103,9 @@
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 @@
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 @@
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 @@
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 @@
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);