netdev - Re: [PATCH net-next v2 0/6] Suspend IRQs during application busy periods

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Message-ID: <ZyEhJXCrZgBLMJgB@LQ3V64L9R2>
Date: Tue, 29 Oct 2024 10:53:41 -0700
From: Joe Damato <jdamato@...tly.com>
To: Paolo Abeni <pabeni@...hat.com>
Cc: netdev@...r.kernel.org, namangulati@...gle.com, edumazet@...gle.com,
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	Xuan Zhuo <xuanzhuo@...ux.alibaba.com>
Subject: Re: [PATCH net-next v2 0/6] Suspend IRQs during application busy
 periods

On Tue, Oct 29, 2024 at 11:25:18AM +0100, Paolo Abeni wrote:
> On 10/21/24 03:52, Joe Damato wrote:

[...]

> 
> The changes makes sense to me, and I could not find any obvious issue in
> the patches.
> 
> I think this deserve some - even basic - self-tests coverage. Note that
> you can enable GRO on veth devices to make NAPI instances avail there.
> 
> Possibly you could opt for a drivers/net defaulting to veth usage and
> allowing the user to select real H/W via env variables.

Sorry, Paolo, but I took a cursory look at veth and I need to object
more strongly to your feedback here.

My understanding (which could be incorrect) is that neither veth nor
netdevsim use IRQs.

The whole purpose of this series is to block IRQs while data is
being busy polled to increase efficiency. That's in the cover
letter.

If neither of the drivers we'd use to simulate this in selftest use
IRQs, how could we build a selftest which ensures IRQs are correctly
suspended during busy periods without first making considerable
changes to either (or both?) drivers?

Respectfully: I don't think it's appropriate to block this series on
that much additional work.

Please reconsider and let me know how to proceed.