Pablo Neira Ayuso <[email protected]> wrote:
> > I was thinking of the cleanup we do in the netns exit path
> > (in nf_conntrack_cleanup_net_list() ).
>
> Right, but in that path we still have entries in the table.
Not necessarily, they might have already been removed
(timeout, close).
> > If you don't like this I can move the check here:
> >
> > i_see_dead_people:
> > busy = 0;
> > list_for_each_entry(net, net_exit_list, exit_list) {
> > // here
> > if (atomic_read .. > 0)
> > nf_ct_iterate_cleanup(net, kill_all, ...
>
> I don't mind about placing this or there, as I said, my question is
> how often we will hit this optimization in a real scenario.
>
> If you think the answer is often, then this will help.
I think the extra atomic_read in this code does no harm and
saves us the entire scan. Also, in the exit path, when we hit the
'i_see_dead_people' label we restart the entire loop, so if we
have 200 netns on the list and the last one caused that restart,
we re-iterate needlesly for 199 netns...
> Otherwise, every time we'll go container destruction path, we'll hit
> slow path, ie. scanning the full table.
Yes, but I see no other choice.
