From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: [PATCH v2] rtmutex: take the waiter lock with irqs off
Date: Fri, 22 Nov 2013 17:21:02 +0100
Message-ID: <528F846E.4000703@linutronix.de>
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Cc: Thomas Gleixner <tglx@linutronix.de>,
	Mike Galbraith <bitbucket@online.de>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>,
	RT <linux-rt-users@vger.kernel.org>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
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On 11/22/2013 05:08 PM, Peter Zijlstra wrote:
> On Fri, Nov 22, 2013 at 02:59:31PM +0100, Sebastian Andrzej Siewior wrote:
>> +extern void __lockfunc rt_spin_try_unlock(spinlock_t *lock);
> 
> I know what you mean, but.. try_unlock() just sounds wrong, how can we
> attempt but fail to unlock a lock we hold ;-)

what about
- rt_spin_unlock_try_or_fail();
- __rt_spin_unlock_dont_use_me()

Couldn't we tell lockdep to bend the rules in this case?

> 
> 
> /me crawls back under his rock ;-)
:)

Sebastian