From owner-freebsd-stable@FreeBSD.ORG Wed Jun 6 21:59:05 2012 Return-Path: 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 8D6B3106564A; Wed, 6 Jun 2012 21:59:05 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140]) by mx1.freebsd.org (Postfix) with ESMTP id 6B0E18FC17; Wed, 6 Jun 2012 21:59:04 +0000 (UTC) Received: from porto.starpoint.kiev.ua (porto-e.starpoint.kiev.ua [212.40.38.100]) by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id AAA10652; Thu, 07 Jun 2012 00:59:02 +0300 (EEST) (envelope-from avg@FreeBSD.org) Received: from localhost ([127.0.0.1]) by porto.starpoint.kiev.ua with esmtp (Exim 4.34 (FreeBSD)) id 1ScOFp-0009PU-H2; Thu, 07 Jun 2012 00:59:02 +0300 Message-ID: <4FCFD2A1.60706@FreeBSD.org> Date: Thu, 07 Jun 2012 00:58:57 +0300 From: Andriy Gapon User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:12.0) Gecko/20120503 Thunderbird/12.0.1 MIME-Version: 1.0 To: Jung-uk Kim References: <1337319129.2915.4.camel@powernoodle-l7> <4FB6765A.2050307@FreeBSD.org> <1337710214.2916.8.camel@powernoodle-l7.corp.yahoo.com> <20120525163653.b61a08e2.lists@yamagi.org> <4FBFA9A9.7020806@FreeBSD.org> <4FBFBD39.7000105@FreeBSD.org> <4FBFDFFB.9020501@FreeBSD.org> <4FBFE624.1020208@FreeBSD.org> <20120526090233.f638c1d2.lists@yamagi.org> <4FC0A3A1.80200@FreeBSD.org> <4FC7D464.20602@FreeBSD.org> In-Reply-To: <4FC7D464.20602@FreeBSD.org> X-Enigmail-Version: 1.5pre Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: sbruno@FreeBSD.org, freebsd-stable@FreeBSD.org, Yamagi Burmeister , seanbru@yahoo-inc.com Subject: Re: [stable 9] broken hwpstate calls X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 06 Jun 2012 21:59:05 -0000 on 31/05/2012 23:28 Jung-uk Kim said the following: > It is simple but I don't like locking scheduler, binding CPU, and writing > the same MSR, multiple times for each core. Not sure if parse this. The MSR is _written_ /once/ for each core. (BTW, "locking scheduler" is not a completely accurate description of what thread_lock does) > Besides, it introduces more delay and you may be reading the correct > status because of that. :-P Having a separate reading pass does introduce more delay indeed. Reading the correct status is a good thing, OTOH. Why would anyone want to read incorrect status? (just want to note that "correct" and "expected" are different things) > If people really think checking MSRC001_0071[18:16] is unworthy for Well, "other people" hasn't demonstrated/proved/convinced yet that it is worthy > Bulldozer, I prefer skipping status check That's what I suggested from the very start. > but I disagree with this patch. Since I am not invested in this issue (I am not affected by the problem and I do not have any personal attachment to the code in question), I will just defer any decision to those who do care about the problem. I hope that a fix will be provided in the end. -- Andriy Gapon