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Date: Thu, 28 Nov 2013 16:18:22 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Tejun Heo <htejun@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>, zhang.yi20@zte.com.cn,
        lkml <linux-kernel@vger.kernel.org>,
        Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        Ingo Molnar <mingo@redhat.com>
Subject: Re: [PATCH]: exec: avoid propagating PF_NO_SETAFFINITY into
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On Thu, Nov 28, 2013 at 10:10:35AM -0500, Tejun Heo wrote:
> On Thu, Nov 28, 2013 at 04:07:04PM +0100, Peter Zijlstra wrote:
> > On Thu, Nov 28, 2013 at 10:02:10AM -0500, Tejun Heo wrote:
> > > > So far I just see you breaking existing setups because you don't want to
> > > > support things that work perfectly well.
> > > 
> > > It doesn't work as explained multiple times in this thread.
> > 
> > It used to.. just not on recent kernels. You know 'enterprise' latency.
> 
> If you're talking about khelfper and wanna restore it, it really
> should be broken out into a separate kthread.  It doesn't make any
> sense to implement that in the workqueue framework.  Why would you
> implement a dedicated task inside a worker pool implementation which
> makes use of the said tasks?  There's even kthread_work interface
> which pretty much provides workqueue-equivalent interface on top of a
> single task for cases like this.

That would only solve one of my problems. People want to contain the
unbound workqueues too.