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Subject: Re: Filesystem lockup with CONFIG_PREEMPT_RT
From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Austin Schuh <austin@peloton-tech.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        Richard Weinberger <richard.weinberger@gmail.com>,
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        Steven Rostedt <rostedt@goodmis.org>
Date: Fri, 27 Jun 2014 05:22:49 +0200
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On Thu, 2014-06-26 at 17:07 -0700, Austin Schuh wrote:

> If I'm reading the rt patch correctly, wq_worker_sleeping was moved
> out of __schedule to sched_submit_work.  It looks like that changes
> the conditions under which wq_worker_sleeping is called.  It used to
> be called whenever a task was going to sleep (I think).  It looks like
> it is called now if the task is going to sleep, and if the task isn't
> blocked on a PI mutex (I think).

Re-entanglement does turn your killer into a happy camper, but that
patch is too lovely to just surrender without a squabble.

-Mike