Date: Thu, 19 Nov 2009 14:22:59 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Peter Zijlstra <peterz@infradead.org>
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>
Subject: Re: yield() in i2c non-happy paths hits BUG under -rt patch
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On Thu, 19 Nov 2009, Peter Zijlstra wrote:

> 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.

yield() sucks anyway, so it depends which flavour of suckage you
prefer.

    tglx
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