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Date:   Thu, 1 Aug 2019 14:17:07 +0100
From:   Qais Yousef <qais.yousef@arm.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     mingo@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/5] Fix FIFO-99 abuse
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On 08/01/19 13:13, Peter Zijlstra wrote:
> I noticed a bunch of kthreads defaulted to FIFO-99, fix them.
> 
> The generic default is FIFO-50, the admin will have to configure the system
> anyway.
> 
> For some the purpose is to be above OTHER and then FIFO-1 really is sufficient.

I was looking in this area too and was thinking of a way to consolidate the
creation of RT/DL tasks in the kernel and the way we set the priority.

Does it make sense to create a new header for RT priorities for kthreads
created in the kernel so that we can easily track and rationale about the
relative priorities of in-kernel RT tasks?

When working in the FW world such a header helped a lot in understanding what
runs at each priority level and how to reason about what priority level makes
sense for a new item. It could be a nice single point of reference; even for
admins.

Cheers

--
Qais Yousef