[PATCH 0/6 RESEND] Add qdisc->ops->peek() support.

[PATCH 0/6 RESEND] Add qdisc->ops->peek() support.

[Jarek Poplawski]

[Subject: Re: [PATCH 00/14]: Killing qdisc->ops->requeue().]
On Tue, Oct 14, 2008 at 10:44:13PM +0200, Patrick McHardy wrote:
...
> I think we really need a peek operation since most qdiscs do have
> some internal priorization. The question is whether all qdiscs need
> it; I tend to think no. Plugging two non-work-conserving qdiscs
> together doesn't make much sense, so we could just prevent this.
> This means we would only need to add ->peek support to the
> work-conserving qdiscs, which looks pretty easy in all cases.
> We actually don't even have to prevent plugging two non-work-conserving
> qdiscs, the ones that need the peek operation could just check whether
> the inner qdisc supports it.
>
> Just as a demonstration how easy adding a peek operation to the
> work-conserving qdiscs actually is. It doesn't need to keep or change
> any internal state in many cases thanks to the guarantee that the
> packet will either be dequeued or, if another packet arrives, the
> upper qdisc will immediately ->peek again to reevaluate the state.

So here is a re-try.

PATCH 6/6 adds my simple idea not to prevent even nonsense configs.
It is optional.

This resend is redone against current net-next with slightly changed
patches 3/6 (check added in register_qdisc()) and 4/6 (teql_peek()
made nonfunctional), according to Patric's suggestions, I hope.

Thanks,
Jarek P.

PS: after this patchset only netem_enqueue() needs qdisc->requeue(),
but this will be handled by a separate patch.

 include/net/sch_generic.h |   29 +++++++++++++++++++++++++++++
 net/sched/sch_api.c       |   12 ++++++++++++
 net/sched/sch_atm.c       |   23 ++++++++++++++++++-----
 net/sched/sch_blackhole.c |    1 +
 net/sched/sch_cbq.c       |    1 +
 net/sched/sch_dsmark.c    |   10 ++++++++++
 net/sched/sch_fifo.c      |    2 ++
 net/sched/sch_generic.c   |   16 ++++++++++++++++
 net/sched/sch_gred.c      |    1 +
 net/sched/sch_hfsc.c      |   15 ++++-----------
 net/sched/sch_htb.c       |    1 +
 net/sched/sch_multiq.c    |   29 +++++++++++++++++++++++++++++
 net/sched/sch_netem.c     |   15 +++++++--------
 net/sched/sch_prio.c      |   14 ++++++++++++++
 net/sched/sch_red.c       |    9 +++++++++
 net/sched/sch_sfq.c       |   12 ++++++++++++
 net/sched/sch_tbf.c       |   13 ++++++-------
 net/sched/sch_teql.c      |    8 ++++++++
 18 files changed, 180 insertions(+), 31 deletions(-)

Re: [PATCH 0/6 RESEND] Add qdisc->ops->peek() support.

[Jarek Poplawski]

On Thu, Oct 30, 2008 at 01:05:18PM +0000, Jarek Poplawski wrote:
...
> PATCH 6/6 adds my simple idea not to prevent even nonsense configs.
> It is optional.

Actually, after a below mentioned change in patch 3/6 this patch isn't
optional anymore.

> This resend is redone against current net-next with slightly changed
> patches 3/6 (check added in register_qdisc()) and 4/6 (teql_peek()
> made nonfunctional), according to Patric's suggestions, I hope.

Sorry for misspelling.

Jarek P.

Re: [PATCH 0/6 RESEND] Add qdisc->ops->peek() support.

[David Miller]

From: Jarek Poplawski <jarkao2@gmail.com>
Date: Thu, 30 Oct 2008 13:05:18 +0000

> So here is a re-try.
> 
> PATCH 6/6 adds my simple idea not to prevent even nonsense configs.
> It is optional.
> 
> This resend is redone against current net-next with slightly changed
> patches 3/6 (check added in register_qdisc()) and 4/6 (teql_peek()
> made nonfunctional), according to Patric's suggestions, I hope.

All applied, thanks a lot Jarek.