diff mbox

[PATCHv2,net-next,2/4] macvtap: Consistently use rcu functions

Message ID 1372190662-30815-3-git-send-email-vyasevic@redhat.com
State Accepted, archived
Delegated to: David Miller
Headers show

Commit Message

Vlad Yasevich June 25, 2013, 8:04 p.m. UTC 
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>
---
 drivers/net/macvtap.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

Comments

Eric Dumazet June 25, 2013, 8:31 p.m. UTC | #1 
On Tue, 2013-06-25 at 16:04 -0400, Vlad Yasevich wrote:
> 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>
> ---
>  drivers/net/macvtap.c | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)

Reviewed-by: Eric Dumazet <edumazet@google.com>


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diff mbox

Patch

diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index efbf2eb..d7856a8 100644
--- 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;
 }