redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

macvtap: Consistently use rcu functions 

Currently macvtap uses rcu_bh functions in its
user facing fuction macvtap_get_user() and macvtap_put_user().
However, its packet handlers use normal rcu as the rcu_read_lock()
is taken in netif_receive_skb().  We can safely discontinue
the usage or rcu with bh disabled.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hifive-unleashed-5.1
Vlad Yasevich 2013-06-25 16:04:20 -04:00 committed by David S. Miller
parent 441ac0fcaa
commit ac4e4af1e5
1 changed files with 9 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
drivers/net/macvtap.c
View File

@ -754,8 +754,8 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
skb_probe_transport_header(skb, ETH_HLEN);
rcu_read_lock_bh();
vlan = rcu_dereference_bh(q->vlan);
rcu_read_lock();
vlan = rcu_dereference(q->vlan);
/* copy skb_ubuf_info for callback when skb has no error */
if (zerocopy) {
skb_shinfo(skb)->destructor_arg = m->msg_control;
@ -766,7 +766,7 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
macvlan_start_xmit(skb, vlan->dev);
else
kfree_skb(skb);
rcu_read_unlock_bh();
rcu_read_unlock();
return total_len;
@ -774,11 +774,11 @@ err_kfree:
kfree_skb(skb);
err:
rcu_read_lock_bh();
vlan = rcu_dereference_bh(q->vlan);
rcu_read_lock();
vlan = rcu_dereference(q->vlan);
if (vlan)
vlan->dev->stats.tx_dropped++;
rcu_read_unlock_bh();
rcu_read_unlock();
return err;
}
@ -854,11 +854,11 @@ static ssize_t macvtap_put_user(struct macvtap_queue *q,
copied += len;
done:
rcu_read_lock_bh();
vlan = rcu_dereference_bh(q->vlan);
rcu_read_lock();
vlan = rcu_dereference(q->vlan);
if (vlan)
macvlan_count_rx(vlan, copied - vnet_hdr_len, ret == 0, 0);
rcu_read_unlock_bh();
rcu_read_unlock();
return ret ? ret : copied;
}