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>

diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index efbf2eb6ae78177da113c5c834d8bf1f26418120..d7856a8f589a7135625051e52737f3461a3eb92c 100644 (file)
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -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;
 }