[PATCH net-next v2 1/9] net: bridge: vlan: drop legacy memory barriers

[Nikolay Aleksandrov <razor@blackwall.org>]

These memory barriers are legacy code from the old vlan implementation
that is not needed anymore. They're also affecting the fast-path.
The pvid is changed under lock and is read with rcu only in the fast-path
there is no need for a barrier, nothing to commit prior to changing it nor
invalidate prior to reading.

Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
---
 net/bridge/br_private.h | 1 -
 net/bridge/br_vlan.c    | 2 --
 2 files changed, 3 deletions(-)

diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index d337b1cfb980..5b2c22ad669e 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -1687,7 +1687,6 @@ static inline u16 br_get_pvid(const struct net_bridge_vlan_group *vg)
 	if (!vg)
 		return 0;
 
-	smp_rmb();
 	return vg->pvid;
 }
 
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
index 1e0e436629ec..2ae6ffb23399 100644
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -40,7 +40,6 @@ static void __vlan_add_pvid(struct net_bridge_vlan_group *vg,
 	if (vg->pvid == v->vid)
 		return;
 
-	smp_wmb();
 	br_vlan_set_pvid_state(vg, v->state);
 	vg->pvid = v->vid;
 }
@@ -50,7 +49,6 @@ static void __vlan_delete_pvid(struct net_bridge_vlan_group *vg, u16 vid)
 	if (vg->pvid != vid)
 		return;
 
-	smp_wmb();
 	vg->pvid = 0;
 }
 
-- 
2.47.3