From owner-freebsd-stable@FreeBSD.ORG  Thu Apr 21 09:04:20 2011
Return-Path: <owner-freebsd-stable@FreeBSD.ORG>
Delivered-To: freebsd-stable@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 94BAE106564A;
	Thu, 21 Apr 2011 09:04:20 +0000 (UTC)
	(envelope-from smithi@nimnet.asn.au)
Received: from sola.nimnet.asn.au (paqi.nimnet.asn.au [115.70.110.159])
	by mx1.freebsd.org (Postfix) with ESMTP id 06EC88FC24;
	Thu, 21 Apr 2011 09:04:19 +0000 (UTC)
Received: from localhost (localhost [127.0.0.1])
	by sola.nimnet.asn.au (8.14.2/8.14.2) with ESMTP id p3L94Hfx062905;
	Thu, 21 Apr 2011 19:04:18 +1000 (EST)
	(envelope-from smithi@nimnet.asn.au)
Date: Thu, 21 Apr 2011 19:04:17 +1000 (EST)
From: Ian Smith <smithi@nimnet.asn.au>
To: Sergey Kandaurov <pluknet@gmail.com>
In-Reply-To: <BANLkTimUCDg7-t9DRubh8LHDdcQv-8Gr0Q@mail.gmail.com>
Message-ID: <20110421181014.R43371@sola.nimnet.asn.au>
References: <4D9EEDAF.3020803@rulez.sk>
	<20110411125416.S35056@sola.nimnet.asn.au>
	<4DA37E31.4020700@FreeBSD.org>
	<20110413024230.Y35056@sola.nimnet.asn.au>
	<20110420164100.Y43371@sola.nimnet.asn.au>
	<BANLkTi=7eS5CC0BMO2WdzasD61g5oCzZpA@mail.gmail.com>
	<BANLkTimUCDg7-t9DRubh8LHDdcQv-8Gr0Q@mail.gmail.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Cc: Daniel Gerzo <danger@freebsd.org>, freebsd-stable@freebsd.org,
	Alexander Motin <mav@freebsd.org>, John Baldwin <jhb@freebsd.org>
Subject: Re: kern.smp.maxid error on i386 UP [was: powerd / cpufreq question]
X-BeenThere: freebsd-stable@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Production branch of FreeBSD source code <freebsd-stable.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>, 
	<mailto:freebsd-stable-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-stable>
List-Post: <mailto:freebsd-stable@freebsd.org>
List-Help: <mailto:freebsd-stable-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>,
	<mailto:freebsd-stable-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 21 Apr 2011 09:04:20 -0000

On Wed, 20 Apr 2011, Sergey Kandaurov wrote:
 > On 20 April 2011 22:29, Sergey Kandaurov <pluknet@gmail.com> wrote:
 > > On 20 April 2011 21:02, Ian Smith <smithi@nimnet.asn.au> wrote:
[..]
 > >> Very happy to test any patches etc.
 > >>
 > >
 > > Ouch.
 > > Looks like that affects a system with 2 cores as well.
 > > Intel Core2 E7200, 8.2-R i386 SMP:
 > >
 > > kern.smp.forward_signal_enabled: 1
 > > kern.smp.topology: 0
 > > kern.smp.cpus: 2
 > > kern.smp.disabled: 0
 > > kern.smp.active: 1
 > > kern.smp.maxcpus: 32
 > > kern.smp.maxid: 31
 > >
 > > kern.cp_times: 867360 171 429180 70114 170549535 1385294 306 176659 82618
 > > 170270900 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 > > 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 > > 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 > > 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 > > 0 0 0 0 0 0 0

Ah, well my quick n dirty fix wouldn't even have helped in that case.

 > Perhaps that was so from the begging: the problem is seen also on
 > 6.4 i386 SMP 8 core. Here it was just set to (MAXCPU-1).

Slightly surprising that it went so long unnoticed on SMP boxes, I guess 
nothing actually fell over due to just inefficiency.

 > The buggy mp_maxid was fixed in HEAD with r215009, though not merged.
 > The patch works on my 8.2 Core2 SMP i386 system.
 > 
 > -- 
 > wbr,
 > pluknet

Thanks Sergey.  Confirming the patch works fine on my non-APIC UP i386:

kern.smp.cpus: 1
kern.smp.disabled: 0
kern.smp.active: 0
kern.smp.maxcpus: 32
kern.smp.maxid: 0
kern.cp_times: 1123 2 1414 5621 277346

cheers, Ian