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From: Stephen Hemminger <stephen@networkplumber.org>
To: Jakub Kicinski <kuba@kernel.org>
Cc: davem@davemloft.net, netdev@vger.kernel.org, edumazet@google.com,
	pabeni@redhat.com, jesse.brandeburg@intel.com,
	anthony.l.nguyen@intel.com, corbet@lwn.net,
	linux-doc@vger.kernel.org
Subject: Re: [PATCH net-next] docs: networking: document NAPI
Date: Wed, 15 Mar 2023 18:36:49 -0700	[thread overview]
Message-ID: <20230315183649.7f42b1f0@hermes.local> (raw)
In-Reply-To: <20230315161142.48de9d98@kernel.org>

On Wed, 15 Mar 2023 16:11:42 -0700
Jakub Kicinski <kuba@kernel.org> wrote:

> > 
> > The one thing missing, is how to handle level vs edge triggered interrupts.
> > For level triggered interrupts, the re-enable is inherently not racy.
> > I.e re-enabling interrupt when packet is present will cause an interrupt.
> > But for devices with edge triggered interrupts, it is often necessary to
> > poll and manually schedule again. Older documentation referred to this
> > as the "rotten packet" problem.
> > 
> > Maybe this is no longer a problem for drivers?
> > Or maybe all new hardware uses PCI MSI and is level triggered?  
> 
> It's still a problem depending on the exact design of the interrupt
> controller in the chip / tradeoffs the SW wants to make.
> I haven't actually read the LF doc, because I wasn't sure about the
> licenses (sigh)

I wrote the old NAPI from some older info that was available back then.

  reply	other threads:[~2023-03-16  1:36 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-15 22:30 [PATCH net-next] docs: networking: document NAPI Jakub Kicinski
2023-03-15 22:46 ` Stephen Hemminger
2023-03-15 22:52 ` Stephen Hemminger
2023-03-15 23:11   ` Jakub Kicinski
2023-03-16  1:36     ` Stephen Hemminger [this message]
2023-03-16 22:59     ` Florian Fainelli
2023-03-16 23:07       ` Jakub Kicinski
2023-03-16 23:18         ` Florian Fainelli
2023-03-15 23:12 ` Tony Nguyen
2023-03-15 23:17   ` Jakub Kicinski
2023-03-15 23:19     ` Jakub Kicinski
2023-03-16  0:20       ` Tony Nguyen
2023-03-16 21:27         ` Tony Nguyen
2023-03-16  1:38 ` Stephen Hemminger
2023-03-16  2:58   ` Jakub Kicinski
2023-03-16 12:03     ` Francois Romieu
2023-03-23  0:44   ` Jamal Hadi Salim
2023-03-16  9:50 ` Bagas Sanjaya
2023-03-16 10:29 ` Toke Høiland-Jørgensen
2023-03-16 21:35   ` Jakub Kicinski
2023-03-16 23:16 ` Florian Fainelli
2023-03-21  0:02   ` Jakub Kicinski
2023-03-21  0:48     ` Stephen Hemminger
2023-03-21  1:19       ` Jakub Kicinski

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