Merge branch 'dev_base_lock-remove'

Eric Dumazet says:

====================
net: complete dev_base_lock removal

Back in 2009 we started an effort to get rid of dev_base_lock
in favor of RCU.

It is time to finish this work.

Say goodbye to dev_base_lock !

v4: rebase, and move dev_addr_sem to net/core/dev.h in patch 06/13 (Jakub)

v3: I misread kbot reports, the issue was with dev->operstate (patch 10/13)
    So dev->reg_state is back to u8, and dev->operstate becomes an u32.
    Sorry for the noise.

v2: dev->reg_state must be a standard enum, some arches
    do not support cmpxchg() on u8.
====================

Signed-off-by: David S. Miller <[email protected]>

1 files changed, 15 insertions, 12 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index a3f9c95da51e..c541550b0e6e 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1815,6 +1815,15 @@ enum netdev_stat_type {
 	NETDEV_PCPU_STAT_DSTATS, /* struct pcpu_dstats */
 };
 
+enum netdev_reg_state {
+	NETREG_UNINITIALIZED = 0,
+	NETREG_REGISTERED,	/* completed register_netdevice */
+	NETREG_UNREGISTERING,	/* called unregister_netdevice */
+	NETREG_UNREGISTERED,	/* completed unregister todo */
+	NETREG_RELEASED,	/* called free_netdev */
+	NETREG_DUMMY,		/* dummy device for NAPI poll */
+};
+
 /**
  *	struct net_device - The DEVICE structure.
  *
@@ -2249,7 +2258,7 @@ struct net_device {
 	const struct tlsdev_ops *tlsdev_ops;
 #endif
 
-	unsigned char		operstate;
+	unsigned int		operstate;
 	unsigned char		link_mode;
 
 	unsigned char		if_port;
@@ -2372,13 +2381,7 @@ struct net_device {
 
 	struct list_head	link_watch_list;
 
-	enum { NETREG_UNINITIALIZED=0,
-	       NETREG_REGISTERED,	/* completed register_netdevice */
-	       NETREG_UNREGISTERING,	/* called unregister_netdevice */
-	       NETREG_UNREGISTERED,	/* completed unregister todo */
-	       NETREG_RELEASED,		/* called free_netdev */
-	       NETREG_DUMMY,		/* dummy device for NAPI poll */
-	} reg_state:8;
+	u8 reg_state;
 
 	bool dismantle;
 
@@ -3074,8 +3077,6 @@ int call_netdevice_notifiers(unsigned long val, struct net_device *dev);
 int call_netdevice_notifiers_info(unsigned long val,
 				  struct netdev_notifier_info *info);
 
-extern rwlock_t				dev_base_lock;		/* Device list lock */
-
 #define for_each_netdev(net, d)		\
 		list_for_each_entry(d, &(net)->dev_base_head, dev_list)
 #define for_each_netdev_reverse(net, d)	\
@@ -5254,7 +5255,9 @@ static inline const char *netdev_name(const struct net_device *dev)
 
 static inline const char *netdev_reg_state(const struct net_device *dev)
 {
-	switch (dev->reg_state) {
+	u8 reg_state = READ_ONCE(dev->reg_state);
+
+	switch (reg_state) {
 	case NETREG_UNINITIALIZED: return " (uninitialized)";
 	case NETREG_REGISTERED: return "";
 	case NETREG_UNREGISTERING: return " (unregistering)";
@@ -5263,7 +5266,7 @@ static inline const char *netdev_reg_state(const struct net_device *dev)
 	case NETREG_DUMMY: return " (dummy)";
 	}
 
-	WARN_ONCE(1, "%s: unknown reg_state %d\n", dev->name, dev->reg_state);
+	WARN_ONCE(1, "%s: unknown reg_state %d\n", dev->name, reg_state);
 	return " (unknown)";
 }