From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: yield() in i2c non-happy paths hits BUG under -rt patch
Date: Thu, 19 Nov 2009 14:21:12 +0100
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Cc: Jean Delvare <khali@linux-fr.org>,
	Leon Woestenberg <leon.woestenberg@gmail.com>,
	Alan Cox <alan@lxorguk.ukuu.org.uk>,
	Mark Brown <broonie@opensource.wolfsonmicro.com>,
	Sven-Thorsten Dietrich <sven@thebigcorporation.com>,
	linux-i2c@vger.kernel.org,
	rt-users <linux-rt-users@vger.kernel.org>,
	"Ben Dooks (embedded platforms)" <ben-linux@fluff.org>,
	LKML <linux-kernel@vger.kernel.org>
To: Thomas Gleixner <tglx@linutronix.de>
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On Thu, 2009-11-19 at 14:11 +0100, Thomas Gleixner wrote:
> > You say "NOOP by default", does this imply there is a way to change
> > this?
> 
> There is a sysctl: sysctl_sched_compat_yield 

This makes yield() place current behind all other tasks, and sucks too
for some workloads.