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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Steven Rostedt' <rostedt@goodmis.org>
CC:     'Vincent Guittot' <vincent.guittot@linaro.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Ingo Molnar <mingo@redhat.com>,
        Juri Lelli <juri.lelli@redhat.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: RE: sched/fair: scheduler not running high priority process on idle
 cpu
Thread-Topic: sched/fair: scheduler not running high priority process on idle
 cpu
Thread-Index: AdXK8cUFXa7JpPXmQNq7oQ32S9fYHAACik4AAADJLkAAAO3PAAAmXEggAAKDBAAAArEnQA==
Date:   Wed, 15 Jan 2020 14:43:26 +0000
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From: Steven Rostedt
> Sent: 15 January 2020 13:19
...
> BTW, I believe distros compile with "CONFIG_IRQ_FORCED_THREADING" which
> means if you add to the kernel command line "threadirqs" the interrupts
> will be run as threads. Which allows for even more preemption.

So they do...
I guess that'll stop the bh code running 'on top of' my RT thread.
But won't help getting the RT process running when the 'events_unbound'
kernel worker is running.

They also use grub2 which is so complicated update-grub is always used
which dumbs everything down to a default set that is hard to change.

	David

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