netdev - Re: [RFC v1 21/22] net: parametrise mp open with a queue config

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAHS8izM-JrPV7R4wk7WnO-Zskb=7gj+HtewoW91cEtsQP1E5rw@mail.gmail.com>
Date: Wed, 6 Aug 2025 11:30:38 -0700
From: Mina Almasry <almasrymina@...gle.com>
To: Jakub Kicinski <kuba@...nel.org>
Cc: Pavel Begunkov <asml.silence@...il.com>, netdev@...r.kernel.org, 
	io-uring@...r.kernel.org, Eric Dumazet <edumazet@...gle.com>, 
	Willem de Bruijn <willemb@...gle.com>, Paolo Abeni <pabeni@...hat.com>, andrew+netdev@...n.ch, 
	horms@...nel.org, davem@...emloft.net, sdf@...ichev.me, dw@...idwei.uk, 
	michael.chan@...adcom.com, dtatulea@...dia.com, ap420073@...il.com
Subject: Re: [RFC v1 21/22] net: parametrise mp open with a queue config

On Wed, Aug 6, 2025 at 11:11 AM Jakub Kicinski <kuba@...nel.org> wrote:
>
> On Wed, 6 Aug 2025 09:48:56 -0700 Mina Almasry wrote:
> > iouring zcrx and devmem can configure netdev_rx_queue->rx_buf_len in
> > addition to netdev_rx_queue->mp_params in this scenario.
>
> Did you not read my message or are you disagreeing that the setting
> should be separate and form a hierarchy?

Sorry, I was disagreeing. The flow above seems complicated. I'm
probably missing something that requires this complication. I was
suggesting an approach I find more straightforward. Something like:

```
  nedev_config = get_driver_defaults()
  qcfg = get_driver_defaults()

  for each setting:
    if qcfg[i].X is set:
       use qcfg[i].X
    else
      use netdev_config.X
```

APIs that set netdev-global attributes could set netdev_config.X. APIs
that set per-queue attributes would set qcfg[i].X (after validating
that the driver supports setting this param on a queue granularity).

With this flow we don't need to duplicate each attribute like
rx-buf-len in 3 different places and have a delicate hierarchy of
serving the config. And we treat mp like any other 'X'. It's just a
setting that exists per-queue but not per netdev.

Although I don't feel strongly here. If you feel the duplication is
warranted please do go ahead1 :-D

-- 
Thanks,
Mina