[PATCH 1/3] lib: dpdk spec to skip red for ingress policer

[Jerin Jacob]

On Wed, Jan 18, 2023 at 1:39 PM Rakesh Kudurumalla
<rkudurumalla at marvell.com> wrote:
>
>
>
> > -----Original Message-----
> > From: Rakesh Kudurumalla
> > Sent: Tuesday, January 10, 2023 12:12 PM
> > To: Ori Kam <orika at nvidia.com>; Jerin Jacob <jerinjacobk at gmail.com>;
> > Stephen Hemminger <stephen at networkplumber.org>
> > Cc: NBU-Contact-Thomas Monjalon (EXTERNAL) <thomas at monjalon.net>;
> > Ferruh Yigit <ferruh.yigit at amd.com>; Andrew Rybchenko
> > <andrew.rybchenko at oktetlabs.ru>; dev at dpdk.org; NBU-Contact-Adrien
> > Mazarguil (EXTERNAL) <adrien.mazarguil at 6wind.com>
> > Subject: RE: [PATCH 1/3] lib: dpdk spec to skip red for ingress policer
> >
> >
> >
> > > -----Original Message-----
> > > From: Ori Kam <orika at nvidia.com>
> > > Sent: Monday, December 26, 2022 10:30 PM
> > > To: Jerin Jacob <jerinjacobk at gmail.com>; Stephen Hemminger
> > > <stephen at networkplumber.org>
> > > Cc: Rakesh Kudurumalla <rkudurumalla at marvell.com>; NBU-Contact-
> > Thomas
> > > Monjalon (EXTERNAL) <thomas at monjalon.net>; Ferruh Yigit
> > > <ferruh.yigit at amd.com>; Andrew Rybchenko
> > > <andrew.rybchenko at oktetlabs.ru>; dev at dpdk.org; NBU-Contact-Adrien
> > > Mazarguil (EXTERNAL) <adrien.mazarguil at 6wind.com>
> > > Subject: [EXT] RE: [PATCH 1/3] lib: dpdk spec to skip red for ingress
> > > policer
> > >
> > > External Email
> > >
> > > ----------------------------------------------------------------------
> > > Hi All,
> > >
> > > > -----Original Message-----
> > > > From: Jerin Jacob <jerinjacobk at gmail.com>
> > > > Sent: Thursday, 22 December 2022 7:27
> > > >
> > > > On Thu, Dec 22, 2022 at 8:32 AM Stephen Hemminger
> > > > <stephen at networkplumber.org> wrote:
> > > > >
> > > > > On Thu, 22 Dec 2022 07:09:02 +0530 Rakesh Kudurumalla
> > > > > <rkudurumalla at marvell.com> wrote:
> > > > >
> > > > > > Dropping of packets based on RED can be skipped with meter
> > > > > > action, when RED is configured using
> > > > > > rte_eth_cman_config_set()
> > > > > >
> > > > > > Signed-off-by: Rakesh Kudurumalla <rkudurumalla at marvell.com>
> > > > >
> > > > > Should this be more general and apply to all congestion management
> > > > > options. Assuming the hardware can do something better than RED.
> > > >
> > > > Yes. We can use "enum rte_cman_mode mode" in the descriptor to
> > > > future- proof.
> > >
> > > I'm missing the idea of this new action, I understand that is related
> > > to Jerin congestion patches.
> > > But I fail to see why we need it? Is it to mark some metadata that
> > > will have some effect on the congestion result? (I assume the system
> > > is implemented in the HW)
> >
> > Yes. It is implemented in HW. Congestion management is applied on ethdev
> > Rx queue using rte_eth_cman_config() API. Once it is configured, it applies to
> > all the packets that steer towards that particular ethdev Rx queue. This
> > feature help to skip the congestion management processing based on the
> > packet color identified by the rte_flow meter object. For example, If one Rx
> > queue configured as RED congestion  and application wants to bypass the
> > RED congestion  processing for all GREEN color packet can be expressed
> > though this API proposal.
>
> Hi Ori Kam,
>
> Let me know if above information  would give clear idea on skip RED action


Rakesh, Adding extra rewording to make it clear.

git comment:

ethdev: introduce flow action to skip congestion management configuration

Using rte_eth_cman_config_set() API the application can configure
ethdev Rx queue's congestion
mechanism. Introducing RTE_FLOW_ACTION_TYPE_SKIP_CMAN flow action to skip the
congestion configuration applied to the given ethdev Rx queue.

This feature helps to skip the congestion management processing based
on per flow or
the packet color identified by the rte_flow meter object.
For example, If one Rx queue configured as RED congestion and
application wants to
bypass the RED congestion  processing for all GREEN color packet can
be expressed
though RTE_FLOW_ACTION_TYPE_SKIP_CMAN flow action.


code:

/**
 * Skip congestion management configuration
 *
 * Skip the congestion management configuration applied using
rte_eth_cman_config_set()
 * API on the given ethdev Rx queue.
 */
RTE_FLOW_ACTION_TYPE_SKIP_CMAN