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From:   John Stultz <jstultz@google.com>
Date:   Tue, 4 Oct 2022 18:13:52 -0700
Message-ID: <CANDhNCrGoWWaoYfsqVOqqNBsbZk5vXjsktrqKYM92-9LpD5P9w@mail.gmail.com>
Subject: Re: [RFC PATCH v4 2/3] sched: Avoid placing RT threads on cores
 handling long softirqs
To:     Hillf Danton <hdanton@sina.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, linux-mm@kvack.org,
        "Connor O'Brien" <connoro@google.com>,
        Qais Yousef <qais.yousef@arm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Steven Rostedt <rostedt@goodmis.org>
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On Tue, Oct 4, 2022 at 5:22 PM Hillf Danton <hdanton@sina.com> wrote:
> On 3 Oct 2022 19:29:36 -0700 John Stultz <jstultz@google.com>
> >
> > Why would ksoftirqd preempt the rt task?
> >
> For example the kthread becomes sensitive to latency.

Again, my apologies, I'm still not sure I am following. Could you
expand a bit on the case you're concerned about? Is it the case where
the ksoftirqd thread is configured to run at higher rtprio?

thanks
-john