From 6b660c4177aaebdc73df7a3378f0e8b110aa4b51 Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Sat, 6 Jul 2019 01:08:09 +0900 Subject: [PATCH] net: openvswitch: do not update max_headroom if new headroom is equal to old headroom When a vport is deleted, the maximum headroom size would be changed. If the vport which has the largest headroom is deleted, the new max_headroom would be set. But, if the new headroom size is equal to the old headroom size, updating routine is unnecessary. Signed-off-by: Taehee Yoo Tested-by: Greg Rose Reviewed-by: Greg Rose Signed-off-by: David S. Miller --- net/openvswitch/datapath.c | 39 +++++++++++++++++++++++++++----------- 1 file changed, 28 insertions(+), 11 deletions(-) diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index 33b388103741..892287d06c17 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -1958,10 +1958,9 @@ static struct vport *lookup_vport(struct net *net, } -/* Called with ovs_mutex */ -static void update_headroom(struct datapath *dp) +static unsigned int ovs_get_max_headroom(struct datapath *dp) { - unsigned dev_headroom, max_headroom = 0; + unsigned int dev_headroom, max_headroom = 0; struct net_device *dev; struct vport *vport; int i; @@ -1975,10 +1974,19 @@ static void update_headroom(struct datapath *dp) } } - dp->max_headroom = max_headroom; + return max_headroom; +} + +/* Called with ovs_mutex */ +static void ovs_update_headroom(struct datapath *dp, unsigned int new_headroom) +{ + struct vport *vport; + int i; + + dp->max_headroom = new_headroom; for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) - netdev_set_rx_headroom(vport->dev, max_headroom); + netdev_set_rx_headroom(vport->dev, new_headroom); } static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info) @@ -1989,6 +1997,7 @@ static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info) struct sk_buff *reply; struct vport *vport; struct datapath *dp; + unsigned int new_headroom; u32 port_no; int err; @@ -2050,8 +2059,10 @@ restart: info->snd_portid, info->snd_seq, 0, OVS_VPORT_CMD_NEW); - if (netdev_get_fwd_headroom(vport->dev) > dp->max_headroom) - update_headroom(dp); + new_headroom = netdev_get_fwd_headroom(vport->dev); + + if (new_headroom > dp->max_headroom) + ovs_update_headroom(dp, new_headroom); else netdev_set_rx_headroom(vport->dev, dp->max_headroom); @@ -2122,11 +2133,12 @@ exit_unlock_free: static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info) { - bool must_update_headroom = false; + bool update_headroom = false; struct nlattr **a = info->attrs; struct sk_buff *reply; struct datapath *dp; struct vport *vport; + unsigned int new_headroom; int err; reply = ovs_vport_cmd_alloc_info(); @@ -2152,12 +2164,17 @@ static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info) /* the vport deletion may trigger dp headroom update */ dp = vport->dp; if (netdev_get_fwd_headroom(vport->dev) == dp->max_headroom) - must_update_headroom = true; + update_headroom = true; + netdev_reset_rx_headroom(vport->dev); ovs_dp_detach_port(vport); - if (must_update_headroom) - update_headroom(dp); + if (update_headroom) { + new_headroom = ovs_get_max_headroom(dp); + + if (new_headroom < dp->max_headroom) + ovs_update_headroom(dp, new_headroom); + } ovs_unlock(); ovs_notify(&dp_vport_genl_family, reply, info);