netdev - Re: Cannot set ageing to zero

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Message-ID: <20160126154424.68185099@x240.home>
Date:	Tue, 26 Jan 2016 15:44:24 -0200
From:	Flavio Leitner <fbl@...close.org>
To:	Jiri Pirko <jiri@...nulli.us>
Cc:	netdev <netdev@...r.kernel.org>, Scott Feldman <sfeldma@...il.com>
Subject: Re: Cannot set ageing to zero

On Tue, 26 Jan 2016 18:30:41 +0100
Jiri Pirko <jiri@...nulli.us> wrote:

> Tue, Jan 26, 2016 at 06:26:30PM CET, fbl@...close.org wrote:
> >
> >Hi,
> >
> >After the commit[1] below, we can't set ageing on a Linux bridge
> >device to zero.  It seems rocker needs the minimum value, but we
> >can't break an old and valid Linux bridge behavior.   
> 
> The commit below adds check if the value being set is within
> BR_MIN_AGEING_TIME and BR_MAX_AGEING_TIME. I believe that the check is
> correct as it implements the standard.
>
> Why do you set ageing_time to 0? Why don't just just disable learning?

It's a documented behavior:
http://www.linuxcertif.com/man/5/ifcfg-bridge/
http://www.linuxfoundation.org/collaborate/workgroups/networking/bridge
http://comments.gmane.org/gmane.linux.network.bridge/2060

fbl

> 
> 
> >
> >[1] commit c62987bbd8a1a1664f99e89e3959339350a6131e
> >Author: Scott Feldman <sfeldma@...il.com>
> >Date:   Thu Oct 8 19:23:19 2015 -0700
> >
> >    bridge: push bridge setting ageing_time down to switchdev
> >    
> >    Use SWITCHDEV_F_SKIP_EOPNOTSUPP to skip over ports in bridge that
> >    don't support setting ageing_time (or setting bridge attrs in
> >    general). 
> >    If push fails, don't update ageing_time in bridge and return err
> > to user. 
> >    If push succeeds, update ageing_time in bridge and run gc_timer
> > now to recalabrate when to run gc_timer next, based on new
> > ageing_time. 
> >    Signed-off-by: Scott Feldman <sfeldma@...il.com>
> >    Signed-off-by: Jiri Pirko <jiri@...nulli.us>
> >    Acked-by: Jiri Pirko <jiri@...lanox.com>
> >    Signed-off-by: David S. Miller <davem@...emloft.net>
> >
> >
> >-- 
> >fbl
> >  



-- 
fbl