svn commit: r229633 - stable/9/sys/net

[YongHyeon PYUN]

On Fri, Jan 06, 2012 at 09:50:13AM -0500, John Baldwin wrote:
> On Friday, January 06, 2012 9:24:59 am Gleb Smirnoff wrote:
> > On Fri, Jan 06, 2012 at 08:45:12AM -0500, John Baldwin wrote:
> > J> On Friday, January 06, 2012 3:20:05 am Gleb Smirnoff wrote:
> > J> >   John,
> > J> > 
> > J> > On Thu, Jan 05, 2012 at 07:50:12PM +0000, John Baldwin wrote:
> > J> > J> Author: jhb
> > J> > J> Date: Thu Jan  5 19:50:12 2012
> > J> > J> New Revision: 229633
> > J> > J> URL: http://svn.freebsd.org/changeset/base/229633
> > J> > J> 
> > J> > J> Log:
> > J> > J>   MFC 228089:
> > J> > J>   Change the if_vlan driver to use if_transmit for forwarding packets to the
> > J> > J>   parent interface.  This avoids the overhead of queueing a packet to an IFQ
> > J> > J>   only to immediately dequeue it again.
> > J> > 
> > J> > This should have been merged together with r228967. Now a bug that
> > J> > was successfully discovered and fixed in head/ leaked to stable
> > J> > branches. :(
> > J> > 
> > J> > Can you please merge r228967 to stable/9 and stable/8 ASAP?
> > J> 
> > J> Err, that bug was already present before this change.  I did not expose it.
> > J> 
> > J> I can MFC the stat fixes, but this was already broken in 8 and 9, and is
> > J> broken in 7 as well (likely in older branches than that).
> > 
> > Well, on 8.2-STABLE if_obytes are correctly accounted:
> > 
> > glebius at xxx:~:|>netstat -hI vlan2 1
> >             input        (vlan2)           output
> >    packets  errs idrops      bytes    packets  errs      bytes colls
> >         33     0     0       2.3k          4     0        840     0
> >         36     0     0       2.4k          4     0        442     0
> >         32     0     0       2.3k          6     0        887     0
> > 
> > glebius at xxx:~:|>uname -v
> > FreeBSD 8.2-STABLE #2: Wed Jul  6 13:22:13 MSD 2011
> > 
> > While on 228089 =< head < 228967 they are not:
> > 
> > glebius at xxx2:~:|>netstat -hI vlan77 1
> >             input       (vlan77)           output
> >    packets  errs idrops      bytes    packets  errs      bytes colls
> >       9.1k     0     0         2M        12k     0          0     0
> >        11k     0     0       4.3M        14k     0          0     0
> >        10k     0     0       2.8M        14k     0          0     0
> >       9.4k     0     0       2.3M        13k     0          0     0
> > 
> > glebius at xxx2:~:|>uname -v 
> > FreeBSD 10.0-CURRENT #5 r228769M: Thu Dec 22 19:44:57 MSK 2011
> 
> Hmm, it seems to be a side effect of the IFQ macros.

IFQ_HANDOFF() is no longer called in vlan_transmit() so we needed a
different approach.