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Subject: Re: preempt_schedule_irq() loop question
To:     Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>
Cc:     Ingo Molnar <mingo@kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Julien Thierry <julien.thierry@arm.com>
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 <20190116134521.GG10803@hirez.programming.kicks-ass.net>
 <alpine.DEB.2.21.1901161550460.1749@nanos.tec.linutronix.de>
From:   Valentin Schneider <valentin.schneider@arm.com>
Message-ID: <4d97b838-6e49-4bba-1c9e-6bf51db3e3a2@arm.com>
Date:   Wed, 16 Jan 2019 15:23:28 +0000
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On 16/01/2019 14:57, Thomas Gleixner wrote:
[...]
> 
> I just went back in the history tree and had to figure out that it's my
> fault :)
> 
> preempt_schedule_irq() was introduced to plug a stupid race, but I did not
> notice (and obviously nobody else) that this made the extra loop in the
> entry code pointless. So it's just histerical raisins without any value.
> 

I see, thanks for clearing that up! Credit goes to Julien & Will for
unearthing the oddity.

> Thanks,
> 
> 	tglx
>