DPDK patches and discussions
 help / color / Atom feed
From: Gregory Etelson <getelson@nvidia.com>
To: Ferruh Yigit <ferruh.yigit@intel.com>,
	Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com>,
	"dev@dpdk.org" <dev@dpdk.org>
Cc: Eli Britstein <elibr@nvidia.com>, Oz Shlomo <ozsh@nvidia.com>,
	Ori Kam <orika@nvidia.com>
Subject: Re: [dpdk-dev] [PATCH v4 2/4] ethdev: tunnel offload model
Date: Fri, 16 Oct 2020 09:15:11 +0000
Message-ID: <MN2PR12MB480068B28403AE6EEB3FBAB8A5030@MN2PR12MB4800.namprd12.prod.outlook.com> (raw)
In-Reply-To: <fe84768e-684e-2131-43c6-21ad79ec496f@intel.com>

Hello Feruh,

> Subject: Re: [dpdk-dev] [PATCH v4 2/4] ethdev: tunnel offload model
> 
> External email: Use caution opening links or attachments
> 
> 
> On 10/7/2020 1:36 PM, Gregory Etelson wrote:
> > Hello Harsha,
> >
> >> -----Original Message-----
> >
> > [snip]
> >>
> >> Tunnel vport is an internal construct used by one specific
> >> application: OVS. So, shouldn't the rte APIs also be application
> >> agnostic apart from being vendor agnostic ? For OVS, the match fields
> >> in the existing datapath flow rules contain enough information to
> >> identify the tunnel type.
> >
> > Tunnel offload model was inspired by OVS vport, but it is not part of
> the existing API.
> > It looks like the API documentation should not use that term to avoid
> confusion.
> >
> > [snip]
> >
> > [snip]
> >>
> >> Wouldn't it be better if the APIs do not refer to vports and avoid
> >> percolating it down to the PMD ? My point here is to avoid bringing in
> >> the knowledge of an application specific virtual object (vport) to the
> >> PMD.
> >>
> >
> > As I have mentioned above, the API description should not mention vport.
> > I'll post updated documents.
> >
> >> Here's some other issues that I see with the helper APIs and
> >> vendor-specific variable actions.
> >> 1) The application needs some kind of validation (or understanding) of
> >> the actions returned by the PMD. The application can't just blindly
> >> use the actions specified by the PMD. That is, the decision to pick
> >> the set of actions can't be left entirely to the PMD.
> >> 2) The application needs to learn a PMD-specific way of action
> >> processing for each vendor. For example, how should the application
> >> handle flow-miss, given a different set of actions between two vendors
> >> (if one vendor has already popped the tunnel header while the other
> >> one hasn't).
> >> 3) The end-users/customers won't have a common interface (as in,
> >> consistent actions) to perform tunnel decap action. This becomes a
> >> manageability/maintenance issue for the application while working with
> >> different vendors.
> >>
> >> IMO, the API shouldn't expect the PMD to understand the notion of
> >> vport. The goal here is to offload a flow rule to decap the tunnel
> >> header and forward the packet to a HW endpoint.  The problem is that
> >> we don't have a way to express the "tnl_pop" datapath action to the HW
> >> (decap flow #1, in the context of br-phy in OVS-DPDK) and also we may
> >> not want the HW to really pop the tunnel header at that stage. If this
> >> cannot be expressed with existing rte action types, maybe we should
> >> introduce a new action that clearly defines what is expected to the
> >> PMD.
> >
> > Tunnel Offload API provides a common interface for all HW vendors:
> > Rule #1: define a tunneled traffic and steer / group traffic related to
> > that tunnel
> > Rule #2: within the tunnel selection, run matchers on all packet
> headers,
> > outer and inner, and perform actions on inner headers in case of a
> match.
> > For the rule #1 application provides tunnel matchers and traffic
> selection actions
> > and for rule #2 application provides full header matchers and actions
> for inner parts.
> > The rest is supplied by PMD according to HW and rule type. Application
> does not
> > need to understand exact PMD elements implementation.
> > Helper return value notifies application whether it received requested
> PMD elements or not.
> > If helper completed successfully, it means that application received
> required elements
> > and can complete flow rule compilation.
> > As the result, a packet will be fully offloaded or returned to
> application with enough
> > information to continue processing in SW.
> >
> > [snip]
> >
> > [snip]
> >
> >>> Miss handling
> >>> -------------
> >>> Packets going through multiple rte_flow groups are exposed to hw
> >>> misses due to partial packet processing. In such cases, the software
> >>> should continue the packet's processing from the point where the
> >>> hardware missed.
> >>
> >> Whether the packet goes through multiple groups or not for tunnel
> >> decap processing, should be left to the PMD/HW.  These assumptions
> >> shouldn't be built into the APIs. The encapsulated packet (i,e with
> >> outer headers) should be provided to the application, rather than
> >> making SW understand that there was a miss in stage-1, or stage-n in
> >> HW. That is, HW either processes it entirely, or punts the whole
> >> packet to SW if there's a miss. And the packet should take the normal
> >> processing path in SW (no action offload).
> >>
> >> Thanks,
> >> -Harsha
> >
> > The packet is provided to the application via the standard
> rte_eth_rx_burst API.
> > Additional information about the HW packet processing state is provided
> to
> > the application by the suggested rte_flow_get_restore_info API. It is up
> to the
> > application if to use such provided info, or even if to call this API at
> all.
> >
> > [snip]
> >
> > Regards,
> > Gregory
> >
> 
> 
> Hi Gregory, Sriharsha,
> 
> Is there any output of the discussion?

Tunnel API documentation was updated in V6.

Regards,
Gregory


  reply index

Thread overview: 90+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-25 16:03 [dpdk-dev] [PATCH 0/2] " Gregory Etelson
2020-06-25 16:03 ` [dpdk-dev] [PATCH 1/2] ethdev: allow negative values in flow rule types Gregory Etelson
2020-07-05 13:34   ` Andrew Rybchenko
2020-08-19 14:33     ` Gregory Etelson
2020-06-25 16:03 ` [dpdk-dev] [PATCH 2/2] ethdev: tunnel offload model Gregory Etelson
     [not found]   ` <DB8PR05MB6761ED02BCD188771BDCDE64A86F0@DB8PR05MB6761.eurprd05.prod.outlook.com>
     [not found]     ` <38d3513f-1261-0fbc-7c56-f83ced61f97a@ashroe.eu>
2020-07-01  6:52       ` Gregory Etelson
2020-07-13  8:21         ` Thomas Monjalon
2020-07-13 13:23           ` Gregory Etelson
2020-07-05 14:50   ` Andrew Rybchenko
2020-08-19 14:30     ` Gregory Etelson
2020-07-05 13:39 ` [dpdk-dev] [PATCH 0/2] " Andrew Rybchenko
2020-09-08 20:15 ` [dpdk-dev] [PATCH v2 0/4] Tunnel Offload API Gregory Etelson
2020-09-08 20:15   ` [dpdk-dev] [PATCH v2 1/4] ethdev: allow negative values in flow rule types Gregory Etelson
2020-09-15  4:36     ` Ajit Khaparde
2020-09-15  8:46       ` Andrew Rybchenko
2020-09-15 10:27         ` Gregory Etelson
2020-09-16 17:21           ` Gregory Etelson
2020-09-17  6:49             ` Andrew Rybchenko
2020-09-17  7:47               ` Ori Kam
2020-09-17 15:15                 ` Andrew Rybchenko
2020-09-17  7:56               ` Gregory Etelson
2020-09-17 15:18                 ` Andrew Rybchenko
2020-09-15  8:45     ` Andrew Rybchenko
2020-09-15 16:17       ` Gregory Etelson
2020-09-08 20:15   ` [dpdk-dev] [PATCH v2 2/4] ethdev: tunnel offload model Gregory Etelson
2020-09-08 20:15   ` [dpdk-dev] [PATCH v2 3/4] net/mlx5: implement tunnel offload API Gregory Etelson
2020-09-08 20:15   ` [dpdk-dev] [PATCH v2 4/4] app/testpmd: support " Gregory Etelson
2020-09-15  4:47     ` Ajit Khaparde
2020-09-15 10:44       ` Gregory Etelson
2020-09-30  9:18 ` [dpdk-dev] [PATCH v3 0/4] Tunnel Offload API Gregory Etelson
2020-09-30  9:18   ` [dpdk-dev] [PATCH v3 1/4] ethdev: allow negative values in flow rule types Gregory Etelson
2020-10-04  5:40     ` Ajit Khaparde
2020-10-04  9:24       ` Gregory Etelson
2020-09-30  9:18   ` [dpdk-dev] [PATCH v3 2/4] ethdev: tunnel offload model Gregory Etelson
2020-09-30  9:18   ` [dpdk-dev] [PATCH v3 3/4] net/mlx5: implement tunnel offload API Gregory Etelson
2020-09-30  9:18   ` [dpdk-dev] [PATCH v3 4/4] app/testpmd: add commands for " Gregory Etelson
2020-10-01  5:32     ` Ajit Khaparde
2020-10-01  9:05       ` Gregory Etelson
2020-10-04  5:40         ` Ajit Khaparde
2020-10-04  9:29           ` Gregory Etelson
2020-10-04 13:50 ` [dpdk-dev] [PATCH v4 0/4] Tunnel Offload API Gregory Etelson
2020-10-04 13:50   ` [dpdk-dev] [PATCH v4 1/4] ethdev: allow negative values in flow rule types Gregory Etelson
2020-10-14 23:40     ` Thomas Monjalon
2020-10-04 13:50   ` [dpdk-dev] [PATCH v4 2/4] ethdev: tunnel offload model Gregory Etelson
2020-10-06  9:47     ` Sriharsha Basavapatna
2020-10-07 12:36       ` Gregory Etelson
2020-10-14 17:23         ` Ferruh Yigit
2020-10-16  9:15           ` Gregory Etelson [this message]
2020-10-14 23:55     ` Thomas Monjalon
2020-10-04 13:50   ` [dpdk-dev] [PATCH v4 3/4] net/mlx5: implement tunnel offload API Gregory Etelson
2020-10-04 13:50   ` [dpdk-dev] [PATCH v4 4/4] app/testpmd: add commands for " Gregory Etelson
2020-10-04 13:59     ` Ori Kam
2020-10-14 17:25   ` [dpdk-dev] [PATCH v4 0/4] Tunnel Offload API Ferruh Yigit
2020-10-15 12:41 ` [dpdk-dev] [PATCH v5 0/3] " Gregory Etelson
2020-10-15 12:41   ` [dpdk-dev] [PATCH v5 1/3] ethdev: allow negative values in flow rule types Gregory Etelson
2020-10-15 12:41   ` [dpdk-dev] [PATCH v5 2/3] ethdev: tunnel offload model Gregory Etelson
2020-10-15 12:41   ` [dpdk-dev] [PATCH v5 3/3] app/testpmd: add commands for tunnel offload API Gregory Etelson
2020-10-15 22:47   ` [dpdk-dev] [PATCH v5 0/3] Tunnel Offload API Ferruh Yigit
2020-10-16  8:55 ` [dpdk-dev] [PATCH v6 " Gregory Etelson
2020-10-16  8:55   ` [dpdk-dev] [PATCH v6 1/3] ethdev: allow negative values in flow rule types Gregory Etelson
2020-10-16  8:55   ` [dpdk-dev] [PATCH v6 2/3] ethdev: tunnel offload model Gregory Etelson
2020-10-16  8:55   ` [dpdk-dev] [PATCH v6 3/3] app/testpmd: add commands for tunnel offload API Gregory Etelson
2020-10-16 10:33 ` [dpdk-dev] [PATCH v7 0/3] Tunnel Offload API Gregory Etelson
2020-10-16 10:33   ` [dpdk-dev] [PATCH v7 1/3] ethdev: allow negative values in flow rule types Gregory Etelson
2020-10-16 10:33   ` [dpdk-dev] [PATCH v7 2/3] ethdev: tunnel offload model Gregory Etelson
2020-10-16 10:34   ` [dpdk-dev] [PATCH v7 3/3] app/testpmd: add commands for tunnel offload API Gregory Etelson
2020-10-16 12:10   ` [dpdk-dev] [PATCH v7 0/3] Tunnel Offload API Ferruh Yigit
2020-10-16 12:51 ` [dpdk-dev] [PATCH v8 " Gregory Etelson
2020-10-16 12:51   ` [dpdk-dev] [PATCH v8 1/3] ethdev: allow negative values in flow rule types Gregory Etelson
2020-10-16 12:51   ` [dpdk-dev] [PATCH v8 2/3] ethdev: tunnel offload model Gregory Etelson
2020-10-16 15:41     ` Kinsella, Ray
2020-10-16 12:51   ` [dpdk-dev] [PATCH v8 3/3] app/testpmd: add commands for tunnel offload API Gregory Etelson
2020-10-16 13:19   ` [dpdk-dev] [PATCH v8 0/3] Tunnel Offload API Ferruh Yigit
2020-10-16 14:20     ` Ferruh Yigit
2020-10-18 12:15 ` [dpdk-dev] [PATCH] ethdev: rename tunnel offload callbacks Gregory Etelson
2020-10-19  8:31   ` Ferruh Yigit
2020-10-19  9:56     ` Kinsella, Ray
2020-10-19 21:29       ` Thomas Monjalon
2020-10-21  9:22 ` [dpdk-dev] [PATCH] net/mlx5: implement tunnel offload API Gregory Etelson
2020-10-22 16:00 ` [dpdk-dev] [PATCH v2] " Gregory Etelson
2020-10-23 13:49 ` [dpdk-dev] [PATCH v3] " Gregory Etelson
2020-10-23 13:57 ` [dpdk-dev] [PATCH v4] " Gregory Etelson
2020-10-25 14:08 ` [dpdk-dev] [PATCH v5] " Gregory Etelson
2020-10-25 15:01   ` Raslan Darawsheh
2020-10-27 16:12 ` [dpdk-dev] [PATCH] net/mlx5: tunnel offload code cleanup Gregory Etelson
2020-10-27 16:29   ` Slava Ovsiienko
2020-10-27 17:16   ` Raslan Darawsheh
2020-10-28 12:33     ` Andrew Rybchenko
2020-10-28  4:58 ` [dpdk-dev] [PATCH] net/mlx5: fix tunnel flow destroy Gregory Etelson
2020-11-02 16:27   ` Raslan Darawsheh

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=MN2PR12MB480068B28403AE6EEB3FBAB8A5030@MN2PR12MB4800.namprd12.prod.outlook.com \
    --to=getelson@nvidia.com \
    --cc=dev@dpdk.org \
    --cc=elibr@nvidia.com \
    --cc=ferruh.yigit@intel.com \
    --cc=orika@nvidia.com \
    --cc=ozsh@nvidia.com \
    --cc=sriharsha.basavapatna@broadcom.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

DPDK patches and discussions

Archives are clonable:
	git clone --mirror http://inbox.dpdk.org/dev/0 dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dev dev/ http://inbox.dpdk.org/dev \
		dev@dpdk.org
	public-inbox-index dev


Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.dev


AGPL code for this site: git clone https://public-inbox.org/ public-inbox