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Date: Wed, 16 Aug 2017 15:14:46 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Waiman Long <longman@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>,
        Jeff Layton <jlayton@poochiereds.net>,
        "J. Bruce Fields" <bfields@fieldses.org>,
        Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org,
        linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] blktrace: Fix potentail deadlock between delete & sysfs
 ops
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On Wed, 16 Aug 2017 15:07:25 -0400
Waiman Long <longman@redhat.com> wrote:


> I am thinking about maybe letting a RT task to sleep a tiny amount of
> time instead of calling schedule(). Hopefully, that will allow a
> lower-priority task to make forward progress.

That is actually one of the ugly hacks we have in the PREEMPT_RT patch
(and one of the things we need to fix before getting it to mainline).

A simple msleep(1).

-- Steve