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Date: Fri, 17 Jun 2016 10:25:59 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Oleg Drokin <green@linuxhacker.ru>
Cc: Mailing List <linux-kernel@vger.kernel.org>, mingo@redhat.com,
        arjan@linux.intel.com, "J . Bruce Fields" <bfields@fieldses.org>,
        Jeff Layton <jlayton@poochiereds.net>
Subject: Re: initialize a mutex into locked state?
Message-ID: <20160617082559.GD30935@twins.programming.kicks-ass.net>
References: <55315ADD-4AE1-4EA4-8291-1B07F659BD99@linuxhacker.ru>
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On Wed, Jun 15, 2016 at 02:23:35PM -0400, Oleg Drokin wrote:
> Hello!
> 
>   To my surprise I found out that it's not possible to initialise a mutex into
>   a locked state.
>   I discussed it with Arjan and apparently there's no fundamental reason
>   not to allow this.

There is. A mutex _must_ have an owner. If you can initialize it in
locked state, you could do so statically, ie. outside of the context of
a task.