[ovs-git] [openvswitch/ovs] 363861: netdev-linux: Make htb quantum always no less than...

[GitHub]

  Branch: refs/heads/branch-2.3
  Home:   https://github.com/openvswitch/ovs
  Commit: 3638617df538b3ab945fcebb10d25ca272c3a6ca
      https://github.com/openvswitch/ovs/commit/3638617df538b3ab945fcebb10d25ca272c3a6ca
  Author: Alex Wang <alexw at nicira.com>
  Date:   2015-03-27 (Fri, 27 Mar 2015)

  Changed paths:
    M lib/netdev-linux.c

  Log Message:
  -----------
  netdev-linux: Make htb quantum always no less than mtu.

Currently, ovs uses hardcoded rate2quantum = 10 for each htb qdisc.
When qdisc class's rate is small, the resulting quantum (calculated
by min_rate / rate2quantum) will be smaller than MTU.  This is not
recommended and tc will keep complaining the following in syslog.

localhost kernel: HTB: quantum of class 10003 is small. Consider r2q change.
localhost kernel: HTB: quantum of class 10004 is small. Consider r2q change.
localhost kernel: HTB: quantum of class 10005 is small. Consider r2q change.
localhost kernel: HTB: quantum of class 10006 is small. Consider r2q change.

To fix the issue, this commit makes ovs always use htb quantum no less
than the MTU.

Signed-off-by: Alex Wang <alexw at nicira.com>
Acked-by: Ben Pfaff <blp at nicira.com>