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Sender: Tejun Heo <htejun@gmail.com>
Date:   Tue, 29 Mar 2022 06:57:53 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Marc Kleine-Budde <mkl@pengutronix.de>,
        Peter Hurley <peter@hurleysoftware.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Esben Haabendal <esben@geanix.com>,
        Steven Walter <stevenrwalter@gmail.com>,
        linux-kernel@vger.kernel.org,
        Oleksij Rempel <o.rempel@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        =?iso-8859-1?Q?Andr=E9?= Pribil <a.pribil@beck-ipc.com>,
        Jiri Slaby <jirislaby@kernel.org>,
        linux-rt-users@vger.kernel.org
Subject: Re: [RFC PATCH 0/2] RT scheduling policies for workqueues
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Hello,

On Tue, Mar 29, 2022 at 10:33:19AM +0200, Rasmus Villemoes wrote:
> On 29/03/2022 08.30, Sebastian Andrzej Siewior wrote:
> > On 2022-03-28 07:39:25 [-1000], Tejun Heo wrote:
> >> Hello,
> > Hi,
> > 
> >> I wonder whether it'd be useful to provide a set of wrappers which can make
> >> switching between workqueue and kworker easy. Semantics-wise, they're
> >> already mostly aligned and it shouldn't be too difficult to e.g. make an
> >> unbounded workqueue be backed by a dedicated kthread_worker instead of
> >> shared pool depending on a flag, or even allow switching dynamically.
> 
> Well, that would certainly not make it any easier for userspace to
> discover the thread it needs to chrt().

Each workqueue have a name and it's not difficult to make dedicated workers
created this way to inherit the name. From user's pov, it's not that
complicated - if kttyd (or whatever) is present, the user can twiddle with
its scheduling class and priority.

Thanks.

-- 
tejun