diff options
| author | Roopa Prabhu <roopa@cumulusnetworks.com> | 2016-08-30 21:56:45 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-09-01 16:56:15 -0700 |
| commit | d297653dd6f07afbe7e6c702a4bcd7615680002e (patch) | |
| tree | e1db2aa802f30afcb2849e8b5a4a2c12866d86d0 /include/linux | |
| parent | 66fdd05e7a85564f86d9b220de946aa98e8bc048 (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 'include/linux')
| -rw-r--r-- | include/linux/netdevice.h | 4 | ||||
| -rw-r--r-- | include/linux/rtnetlink.h | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index d122be9345c7..67bb978470dc 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1031,7 +1031,7 @@ struct netdev_xdp { * Deletes the FDB entry from dev coresponding to addr. * int (*ndo_fdb_dump)(struct sk_buff *skb, struct netlink_callback *cb, * struct net_device *dev, struct net_device *filter_dev, - * int idx) + * int *idx) * Used to add FDB entries to dump requests. Implementers should add * entries to skb and update idx with the number of entries. * @@ -1263,7 +1263,7 @@ struct net_device_ops { struct netlink_callback *cb, struct net_device *dev, struct net_device *filter_dev, - int idx); + int *idx); int (*ndo_bridge_setlink)(struct net_device *dev, struct nlmsghdr *nlh, diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h index 2daece8979f7..57e54847b0b9 100644 --- a/include/linux/rtnetlink.h +++ b/include/linux/rtnetlink.h @@ -105,7 +105,7 @@ extern int ndo_dflt_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb, struct net_device *dev, struct net_device *filter_dev, - int idx); + int *idx); extern int ndo_dflt_fdb_add(struct ndmsg *ndm, struct nlattr *tb[], struct net_device *dev, |