Message-ID: <1376114128.5332.17.camel@marge.simpson.net>
Subject: Re: Re-tune x86 uaccess code for PREEMPT_VOLUNTARY
From: Mike Galbraith <bitbucket@online.de>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>, linux-kernel@vger.kernel.org,
        x86@kernel.org, mingo@kernel.org, torvalds@linux-foundation.org
Date: Sat, 10 Aug 2013 07:55:28 +0200
In-Reply-To: <5205C4BB.6020003@zytor.com>
References: <1376089460-5459-1-git-send-email-andi@firstfloor.org>
	 <5205C4BB.6020003@zytor.com>
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On Fri, 2013-08-09 at 21:42 -0700, H. Peter Anvin wrote: 
> On 08/09/2013 04:04 PM, Andi Kleen wrote:
> > 
> > This patch kit is an attempt to get us back to sane code, 
> > mostly by doing proper inlining and doing sleep checks in the right
> > place. Unfortunately I had to add one tree sweep to avoid an nasty
> > include loop.
> > 
> > It costs a bit of text space, but I think it's worth it
> > (if only to keep my blood pressure down while reading ftrace logs...)
> > 
> 
> Looks nice at first glance.
> 
> Now, here is a bigger question: shouldn't we be deprecating/getting rid
> of PREEMPT_VOUNTARY in favor of PREEMPT?

I sure hope not, PREEMPT munches throughput.  If you need PREEMPT, seems
to me what you _really_ need is PREEMPT_RT (the real deal), so
eventually depreciating PREEMPT makes more sense to me.

-Mike

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