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Date:   Mon, 26 Mar 2018 11:59:04 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     joe.korty@concurrent-rt.com
Cc:     Julia Cartwright <julia@ni.com>, <bigeasy@linutronix.de>,
        <mingo@redhat.com>, <tglx@linutronix.de>,
        <linux-rt-users@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH RT] Defer migrate_enable migration while task state !=
 TASK_RUNNING
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On Mon, 26 Mar 2018 11:54:51 -0400
joe.korty@concurrent-rt.com wrote:

> Oh well.  Makes me wonder why might_sleep is testing for
> !TASK_RUNNABLE though.

Because might_sleep() is used when the function might call schedule()
directly. And schedule() *will* change the task state to TASK_RUNNING.
might_sleep() has nothing to do with preemption.

-- Steve