Re: CVS commit: src/sys

[Ryota Ozaki <ozaki-r%netbsd.org@localhost>]

On Tue, Dec 2, 2014 at 8:25 PM, Antti Kantee <pooka%iki.fi@localhost> wrote:
> [like pros, we were talking on source-changes list.  that wasn't very
> useful]
>
> On 02/12/14 04:28, Ryota Ozaki wrote:
>>
>> On Tue, Dec 2, 2014 at 12:39 PM, Antti Kantee <pooka%iki.fi@localhost> wrote:
>>>
>>> On 02/12/14 03:30, Ryota Ozaki wrote:
>>>>>
>>>>>
>>>>> The problem is that the real if_drain_all() will never be called in
>>>>> environments with the weak alias problem even if the non-stub
>>>>> implementation
>>>>> is present and it should be called.
>>>>
>>>>
>>>>
>>>> I'm getting the problem, but I have still one question; why ifnet_list
>>>> works while if_drain_all doesn't?
>>>
>>>
>>>
>>> If you are asking about the linker, ifnet_list is a common symbol, not a
>>> weak alias.
>>>
>>> If you are asking about traversing ifnet_list, semi-accidentally -- the
>>> tailq macros happen to work for zero-filled heads unless you try to
>>> tailq_insert_tail.
>>
>>
>> I meant the former. Anyway I got it. rumpnet doesn't add any items
>> to ifnet_list, so it works without rumpnet_net.
>
>
> Right, because interfaces don't exist in net, only in net_net (it makes
> sense if you think about sys vs. sys/net).
>
>>>>> Actually, looking more closely, it is currently a problem for _all_
>>>>> platforms since you stubbed it to a panic instead of a nop.
>>>>
>>>>
>>>>
>>>> Oh, right. I just followed bridge ones...
>>>
>>>
>>>
>>> If you look at the history of that file, you will notice that I have been
>>> removing __weak_alias() instances.  bridge/agr not working on platforms
>>> without weak alias support is acceptable (because it never has worked).
>>>
>>> I hope bridge/agr can be fixed some day, but perhaps they will fix
>>> themselves with a more modular networking stack ;)
>>
>>
>> We can get rid of __weak_alias(bridge_input) already :)
>> The other two are...I don't know when it's done :-/
>
>
> Oh, nice!  Can you remove the now-unnecessary weak aliases?

Done.

I'm thinking how to remove weak alias for bridge_ifdetach.
It can be done by having a (if)detach callback list that
callbacks are called in ether_ifdetach. We can register
bpf_detach and vlan_ifdetach to the list as well as
bridge_ifdetach. I don't know it's worthwhile to do though.

  ozaki-r