From: Waiman Long <longman@redhat.com>
To: Steven Rostedt <rostedt@goodmis.org>
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 v2] blktrace: Fix potentail deadlock between delete & sysfs ops
Date: Fri, 18 Aug 2017 09:55:58 -0400 [thread overview]
Message-ID: <5a5d0743-d2db-89c8-59cc-542835baeccf@redhat.com> (raw)
In-Reply-To: <20170817173004.263d2891@gandalf.local.home>
On 08/17/2017 05:30 PM, Steven Rostedt wrote:
> On Thu, 17 Aug 2017 17:10:07 -0400
> Steven Rostedt <rostedt@goodmis.org> wrote:
>
>
>> Instead of playing games with taking the lock, the only way this race
>> is hit, is if the partition is being deleted and the sysfs attribute is
>> being read at the same time, correct? In that case, just return
>> -ENODEV, and be done with it.
> Nevermind that wont work. Too bad there's not a mutex_lock_timeout()
> that we could use in a loop. It would solve the issue of forward
> progress with RT tasks, and will break after a timeout in case of
> deadlock.
>
> -- Steve
I think it will be useful to have mutex_timed_lock(). RT-mutex does have
a timed version, so I guess it shouldn't be hard to implement one for
mutex. I can take a shot at trying to do that.
Thanks,
Longman
next prev parent reply other threads:[~2017-08-18 13:56 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-16 20:40 [PATCH v2] blktrace: Fix potentail deadlock between delete & sysfs ops Waiman Long
2017-08-17 13:34 ` Steven Rostedt
2017-08-17 16:24 ` Waiman Long
2017-08-17 20:30 ` Steven Rostedt
2017-08-17 20:41 ` Bart Van Assche
2017-08-17 20:56 ` Steven Rostedt
2017-08-17 21:10 ` Steven Rostedt
2017-08-17 21:27 ` Waiman Long
2017-08-17 22:13 ` Steven Rostedt
2017-08-17 22:18 ` Steven Rostedt
2017-08-17 23:23 ` Steven Rostedt
2017-08-18 13:42 ` Waiman Long
2017-08-17 21:30 ` Steven Rostedt
2017-08-18 13:55 ` Waiman Long [this message]
2017-08-18 16:21 ` Bart Van Assche
2017-08-18 17:22 ` Waiman Long
2017-08-18 17:26 ` Steven Rostedt
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