From: Jakub Kicinski <kuba@kernel.org>
To: Breno Leitao <leitao@debian.org>
Cc: netdev@vger.kernel.org, leit@fb.com, davem@davemloft.net,
edumazet@google.com, pabeni@redhat.com,
sa+renesas@sang-engineering.com, linux-kernel@vger.kernel.org,
Michael van der Westhuizen <rmikey@meta.com>
Subject: Re: [RFC PATCH v2] netpoll: Remove 4s sleep during carrier detection
Date: Thu, 19 Jan 2023 11:04:21 -0800 [thread overview]
Message-ID: <20230119110421.3efc0f6b@kernel.org> (raw)
In-Reply-To: <20230119180008.2156048-1-leitao@debian.org>
On Thu, 19 Jan 2023 10:00:08 -0800 Breno Leitao wrote:
> This patch proposes to remove the msleep(4s) during netpoll_setup() if
> the carrier appears instantly.
>
> Modern NICs do not seem to have this bouncing problem anymore, and this
> sleep slows down the machine boot unnecessarily
We should mention in the message that the wait is counter-productive on
servers which have BMC communicating over NC-SI via the same NIC as gets
used for netconsole. BMC will keep the PHY up, hence the carrier
appearing instantly.
We could add a smaller delay, but really having instant carrier and
then loosing it seems like a driver bug, so let's try to rip the band
aid off and ask for forgiveness instead.
Few extra process rules:
- don't repost another version within 24h,
- keep a changelog under ---
- add tree name to the tag - [PATCH net-next]
Also, I'd just go for PATCH, no need to RFC this.
If someone wants to object they can object to a PATCH.
next prev parent reply other threads:[~2023-01-20 5:07 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-19 16:44 [PATCH] netpoll: Remove 4s sleep during carrier detection Breno Leitao
2023-01-19 18:00 ` [RFC PATCH v2] " Breno Leitao
2023-01-19 19:04 ` Jakub Kicinski [this message]
2023-01-23 13:56 ` Andrew Lunn
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