Netdev List
 help / color / mirror / Atom feed
From: Jakub Kicinski <kuba@kernel.org>
To: Cosmin Ratiu <cratiu@nvidia.com>
Cc: "daniel.zahka@gmail.com" <daniel.zahka@gmail.com>,
	"willemdebruijn.kernel@gmail.com"
	<willemdebruijn.kernel@gmail.com>,
	"edumazet@google.com" <edumazet@google.com>,
	Boris Pismenny <borisp@nvidia.com>,
	"kuniyu@google.com" <kuniyu@google.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>
Subject: Re: [RFC net-next 0/6] psp: use virt cookie as Rx steering hint
Date: Tue, 25 Aug 2026 11:55:18 -0700	[thread overview]
Message-ID: <20260825115518.2b925e90@kernel.org> (raw)
In-Reply-To: <7bddbd246387fe4dfdc1e638b50d44a73aecdc83.camel@nvidia.com>

On Tue, 25 Aug 2026 09:52:09 +0000 Cosmin Ratiu wrote:
> Option 1 would be to only set req_qid on _changes_ (edge transitions)
> and keep it 0 otherwise. Also make it mean queue = req_qid - 1 to allow
> the use of queue 0. Ideally, only the first packet in each direction
> would have req_qid != 0. These packets cannot be decapped and cannot go
> through HW GRO, but all subsequent ones with req_qid == 0 may. dst_qid
> is of course != 0 in all packets and is honored.
> 
> But then you need to make sure those packets aren't lost, and maybe
> retransmit req_qid until it gets received. I thought about it a bit,
> maybe using TCP acks as an indication? Or just trying best-effort a
> couple of times...
> 
> Option 2 would be to just disallow HW GRO with req_qid.

I'd go with Option 2 FWIW and revisit it later if we find out that more
NICs need some sort of workaround.

> And option 3: sport selection to get the desired RSS result makes this
> interaction non-existent.

  reply	other threads:[~2026-08-25 18:55 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-22 22:55 [RFC net-next 0/6] psp: use virt cookie as Rx steering hint Jakub Kicinski
2026-08-22 22:55 ` [RFC net-next 1/6] psp: steer Rx queues with the virtualization cookie Jakub Kicinski
2026-08-23 15:31   ` Daniel Zahka
2026-08-24 15:01     ` Jakub Kicinski
2026-08-24 15:09       ` Cosmin Ratiu
2026-08-24 15:19         ` Jakub Kicinski
2026-08-23 18:18   ` Willem de Bruijn
2026-08-22 22:55 ` [RFC net-next 2/6] netdevsim: support PSP VC based queue steering Jakub Kicinski
2026-08-22 22:55 ` [RFC net-next 3/6] selftests: drv-net: psp: move the PSP test plumbing into psp_lib.py Jakub Kicinski
2026-08-22 22:55 ` [RFC net-next 4/6] selftests: drv-net: psp_steer: test PSP VC based queue steering Jakub Kicinski
2026-08-22 22:55 ` [RFC net-next 5/6] selftests: drv-net: psp_steer: test where PSP steering sits in the Rx pipeline Jakub Kicinski
2026-08-22 22:55 ` [RFC net-next 6/6] selftests: drv-net: psp_steer: cover corner cases and races Jakub Kicinski
2026-08-23 17:48 ` [RFC net-next 0/6] psp: use virt cookie as Rx steering hint Willem de Bruijn
2026-08-24 15:05   ` Cosmin Ratiu
2026-08-25  9:52     ` Cosmin Ratiu
2026-08-25 18:55       ` Jakub Kicinski [this message]
2026-08-24 15:11   ` Jakub Kicinski
2026-08-24 18:04     ` Willem de Bruijn

Reply instructions:

You may reply publicly 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=20260825115518.2b925e90@kernel.org \
    --to=kuba@kernel.org \
    --cc=borisp@nvidia.com \
    --cc=cratiu@nvidia.com \
    --cc=daniel.zahka@gmail.com \
    --cc=edumazet@google.com \
    --cc=kuniyu@google.com \
    --cc=netdev@vger.kernel.org \
    --cc=willemdebruijn.kernel@gmail.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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox