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Date:   Thu, 31 Jan 2019 18:06:53 +0100
From:   Sebastian Sewior <bigeasy@linutronix.de>
To:     Heiko Carstens <heiko.carstens@de.ibm.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        "Paul E. McKenney" <paulmck@linux.ibm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>,
        LKML <linux-kernel@vger.kernel.org>, linux-s390@vger.kernel.org,
        Stefan Liebler <stli@linux.ibm.com>
Subject: Re: WARN_ON_ONCE(!new_owner) within wake_futex_pi() triggerede
Message-ID: <20190131170653.spnrxsiblkssleyd@linutronix.de>
References: <20190130132420.spwrq2d4oxeydk5s@linutronix.de>
 <alpine.DEB.2.21.1901301428390.5537@nanos.tec.linutronix.de>
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 <20190130210733.mg6aascw2gzl3oqz@linutronix.de>
 <alpine.DEB.2.21.1901302314590.8200@nanos.tec.linutronix.de>
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 <alpine.DEB.2.21.1901310049440.8200@nanos.tec.linutronix.de>
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On 2019-01-31 17:52:28 [+0100], Heiko Carstens wrote:
> ...nevertheless Stefan and I looked through the lovely disassembly of
> _pthread_mutex_lock_full() to verify if the compiler barriers are
> actually doing what they are supposed to do. The generated code
> however does look correct.
> So, it must be something different.

would it make sense to use one locking function instead all three (lock,
try-lock, timed) in the test case to figure out if this is related to
one of the locking function?

Sebastian