Re: CVS commit: src/sys/net

[Taylor R Campbell <campbell+netbsd-source-changes-d%mumble.net@localhost>]

   Date: Tue, 16 Feb 2016 16:30:54 +0900
   From: Ryota Ozaki <ozaki-r%netbsd.org@localhost>

   On Tue, Feb 16, 2016 at 6:16 AM, Taylor R Campbell
   <campbell+netbsd-source-changes-d%mumble.net@localhost> wrote:
   > void
   > if_link_state_change(struct ifnet *ifp, int link_state)
   > {
   >         int s;
   >
   >         s = splnet();
   >         if (ifp->if_link_state_pending == link_state)
   >                 goto out;
   >
   >         if (ifp->if_link_state_pending != ifp->if_link_state) {

   What does the conditional intend?

I don't remember!  It doesn't make sense now that I look at it again.
This was just a sketch -- obviously it was missing some parts, such as
pool_cache_put, and some parts seem to make no sense.  I would just
take it out.

   Anyway I made a patch based on the above code:
     http://www.netbsd.org/~ozaki-r/link_state_change.diff

   What I did are to make your code compilable and workable,
   and limit the number of pending events.

Looks reasonable to me.  We should have some automatic tests for all
this, though!