bonding: remove dev_base_lock use

bond_info_seq_start() uses a read_lock(&dev_base_lock) to make sure
device doesn’t disappear. Same goal can be achieved using RCU.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_main.c

@@ -3209,7 +3209,7 @@ void bond_activebackup_arp_mon(struct work_struct *work)
 #ifdef CONFIG_PROC_FS
 
 static void *bond_info_seq_start(struct seq_file *seq, loff_t *pos)
-	__acquires(&dev_base_lock)
+	__acquires(RCU)
 	__acquires(&bond->lock)
 {
 	struct bonding *bond = seq->private;
@@ -3218,7 +3218,7 @@ static void *bond_info_seq_start(struct seq_file *seq, loff_t *pos)
 	int i;
 
 	/* make sure the bond won't be taken away */
-	read_lock(&dev_base_lock);
+	rcu_read_lock();
 	read_lock(&bond->lock);
 
 	if (*pos == 0)
@@ -3248,12 +3248,12 @@ static void *bond_info_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 
 static void bond_info_seq_stop(struct seq_file *seq, void *v)
 	__releases(&bond->lock)
-	__releases(&dev_base_lock)
+	__releases(RCU)
 {
 	struct bonding *bond = seq->private;
 
 	read_unlock(&bond->lock);
-	read_unlock(&dev_base_lock);
+	rcu_read_unlock();
 }
 
 static void bond_info_show_master(struct seq_file *seq)