path: root/drivers/net
diff options
authorRoopa Prabhu <roopa@cumulusnetworks.com>2016-08-30 21:56:45 -0700
committerDavid S. Miller <davem@davemloft.net>2016-09-01 16:56:15 -0700
commitd297653dd6f07afbe7e6c702a4bcd7615680002e (patch)
treee1db2aa802f30afcb2849e8b5a4a2c12866d86d0 /drivers/net
parentrps: flow_dissector: Add the const for the parameter of flow_keys_have_l4 (diff)
rtnetlink: fdb dump: optimize by saving last interface markers
fdb dumps spanning multiple skb's currently restart from the first interface again for every skb. This results in unnecessary iterations on the already visited interfaces and their fdb entries. In large scale setups, we have seen this to slow down fdb dumps considerably. On a system with 30k macs we see fdb dumps spanning across more than 300 skbs. To fix the problem, this patch replaces the existing single fdb marker with three markers: netdev hash entries, netdevs and fdb index to continue where we left off instead of restarting from the first netdev. This is consistent with link dumps. In the process of fixing the performance issue, this patch also re-implements fix done by commit 472681d57a5d ("net: ndo_fdb_dump should report -EMSGSIZE to rtnl_fdb_dump") (with an internal fix from Wilson Kok) in the following ways: - change ndo_fdb_dump handlers to return error code instead of the last fdb index - use cb->args strictly for dump frag markers and not error codes. This is consistent with other dump functions. Below results were taken on a system with 1000 netdevs and 35085 fdb entries: before patch: $time bridge fdb show | wc -l 15065 real 1m11.791s user 0m0.070s sys 1m8.395s (existing code does not return all macs) after patch: $time bridge fdb show | wc -l 35085 real 0m2.017s user 0m0.113s sys 0m1.942s Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: Wilson Kok <wkok@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net')
2 files changed, 10 insertions, 11 deletions
diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
index 3ebef27e0964..3ae3968b0edf 100644
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
@@ -432,18 +432,19 @@ static int qlcnic_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
static int qlcnic_fdb_dump(struct sk_buff *skb, struct netlink_callback *ncb,
struct net_device *netdev,
- struct net_device *filter_dev, int idx)
+ struct net_device *filter_dev, int *idx)
struct qlcnic_adapter *adapter = netdev_priv(netdev);
+ int err = 0;
if (!adapter->fdb_mac_learn)
return ndo_dflt_fdb_dump(skb, ncb, netdev, filter_dev, idx);
if ((adapter->flags & QLCNIC_ESWITCH_ENABLED) ||
- idx = ndo_dflt_fdb_dump(skb, ncb, netdev, filter_dev, idx);
+ err = ndo_dflt_fdb_dump(skb, ncb, netdev, filter_dev, idx);
- return idx;
+ return err;
static void qlcnic_82xx_cancel_idc_work(struct qlcnic_adapter *adapter)
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 3f7e0d2dd21a..f605a3684a7f 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -860,20 +860,20 @@ out:
/* Dump forwarding table */
static int vxlan_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb,
struct net_device *dev,
- struct net_device *filter_dev, int idx)
+ struct net_device *filter_dev, int *idx)
struct vxlan_dev *vxlan = netdev_priv(dev);
unsigned int h;
+ int err = 0;
for (h = 0; h < FDB_HASH_SIZE; ++h) {
struct vxlan_fdb *f;
- int err;
hlist_for_each_entry_rcu(f, &vxlan->fdb_head[h], hlist) {
struct vxlan_rdst *rd;
list_for_each_entry_rcu(rd, &f->remotes, list) {
- if (idx < cb->args[0])
+ if (*idx < cb->args[2])
goto skip;
err = vxlan_fdb_info(skb, vxlan, f,
@@ -881,17 +881,15 @@ static int vxlan_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb,
- if (err < 0) {
- cb->args[1] = err;
+ if (err < 0)
goto out;
- }
- ++idx;
+ *idx += 1;
- return idx;
+ return err;
/* Watch incoming packets to learn mapping between Ethernet address