[ovs-dev] [PATCH 6/6] vxlan: Create and delete tnl_backers in type_run()

Kyle Mestery (kmestery) kmestery at cisco.com
Thu Feb 14 18:47:56 UTC 2013


On Feb 14, 2013, at 12:33 PM, Ben Pfaff <blp at nicira.com> wrote:
> On Thu, Feb 14, 2013 at 09:37:30AM -0500, Kyle Mestery wrote:
>> Garbage collect tnl_backers during type_run(). Add new
>> tnl_backers if a VXLAN ports UDP port changes.
>> 
>> Signed-off-by: Kyle Mestery <kmestery at cisco.com>
> 
> The error handling here is bad.  If it fails to add or remove a port,
> then ovs_assert() aborts the whole ovs-vswitchd process.
> 
I can change the asserts into something more sane.

> But I don't fully understand the code.  It looks to me like the first
> time we encounter a particular dp_port_name in the inner HMAP_FOR_EACH,
> we transfer that dp_port_name from tmp_simap to backer->tnl_backers.
> Straightforward enough.  However, I believe that the second time we
> encounter that same dp_port_name, we will not find it in tmp_simap
> (because we deleted it) and will therefore try to add a new port for
> it.   I believe that will fail, because there is already a port with
> that dst_port, and then we'll assert-fail the process.
> 
> Am I reading the code correctly?
> 
Actually, the second time the same dp_port_name is encountered,
we first look and see if we need to reconfigure it, and then we check if
it's already in backer->tnl_backers, which it will be since we added it
there the first time we found it. I don't see it adding the port twice, unless
I'm misreading it.

> I've now pushed patch 1-4 to master, waiting for an ack from Jesse on
> #5, waiting for your reply on this one.
> 
Thanks Ben! Let me know if you want me to modify the error handling
behavior.

Thanks,
Kyle

> Thanks,
> 
> Ben.





More information about the dev mailing list