From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752987Ab2AZQHI (ORCPT ); Thu, 26 Jan 2012 11:07:08 -0500 Received: from shutemov.name ([176.9.204.213]:40917 "EHLO shutemov.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751894Ab2AZQHG convert rfc822-to-8bit (ORCPT ); Thu, 26 Jan 2012 11:07:06 -0500 Date: Thu, 26 Jan 2012 18:07:45 +0200 From: "Kirill A. Shutemov" To: Greg KH Cc: Michael Tokarev , linux-kernel@vger.kernel.org, stable@vger.kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Thomas Renninger , Bruno Friedmann , Len Brown Subject: Re: [67/90] intel idle: Make idle driver more robust Message-ID: <20120126160745.GA2423@shutemov.name> References: <20120123234211.GA19504@kroah.com> <20120123234028.628058547@clark.kroah.org> <20120126144533.GA1731@shutemov.name> <4F217585.2070302@msgid.tls.msk.ru> <20120126155427.GA2310@shutemov.name> <20120126155925.GA1404@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <20120126155925.GA1404@suse.de> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 26, 2012 at 07:59:25AM -0800, Greg KH wrote: > On Thu, Jan 26, 2012 at 05:54:27PM +0200, Kirill A. Shutemov wrote: > > On Thu, Jan 26, 2012 at 07:47:17PM +0400, Michael Tokarev wrote: > > > 26.01.2012 18:45, Kirill A. Shutemov wrote: > > > > > > >>From: Thomas Renninger > > > >> > > > >>commit 5c2a9f06a9cd7194f884cdc88144866235dec07d upstream. > > > >> > > > >>kvm -cpu host passes the original cpuid info to the guest. > > > >> > > > >>Latest kvm version seem to return true for mwait_leaf cpuid > > > >>function on recent Intel CPUs. But it does not return mwait > > > >>C-states (mwait_substates), instead zero is returned. > > > >> > > > [] > > > >> drivers/idle/intel_idle.c | 3 ++- > > > >> 1 file changed, 2 insertions(+), 1 deletion(-) > > > >> > > > >>--- a/drivers/idle/intel_idle.c > > > >>+++ b/drivers/idle/intel_idle.c > > > >>@@ -321,7 +321,8 @@ static int intel_idle_probe(void) > > > >> cpuid(CPUID_MWAIT_LEAF,&eax,&ebx,&ecx,&mwait_substates); > > > >> > > > >> if (!(ecx& CPUID5_ECX_EXTENSIONS_SUPPORTED) || > > > >>- !(ecx& CPUID5_ECX_INTERRUPT_BREAK)) > > > >>+ !(ecx& CPUID5_ECX_INTERRUPT_BREAK) || > > > >>+ !mwait_substates) > > > >> return -ENODEV; > > > > > > > >It breaks build for me. > > > [] > > > > CC drivers/idle/intel_idle.o > > > >/home/space/kas/git/public/linux-3.0-mid/drivers/idle/intel_idle.c: In function ‘intel_idle_probe’: > > > >/home/space/kas/git/public/linux-3.0-mid/drivers/idle/intel_idle.c:508:7: error: ‘mwait_substates’ undeclared (first use in this function) > > > >/home/space/kas/git/public/linux-3.0-mid/drivers/idle/intel_idle.c:508:7: note: each undeclared identifier is reported only once for each function it appears in > > > >make[3]: *** [drivers/idle/intel_idle.o] Error 1 > > > > > > > >Variable 'substates' hasn't renamed to 'mwait_substates' in 3.0. > > > >See c423628 intel_idle: delete substates DEBUG modparam > > > > > > I wonder why in my 3.0.18 this variable is properly defined > > > in the same file, in line 77: > > > > > > ... > > > 74 /* intel_idle.max_cstate=0 disables driver */ > > > 75 static int max_cstate = MWAIT_MAX_NUM_CSTATES - 1; > > > 76 > > > 77 static unsigned int mwait_substates; > > > 78 > > > 79 #define LAPIC_TIMER_ALWAYS_RELIABLE 0xFFFFFFFF > > > ... > > > > Oosp. Sorry for noise. My local patch breaks it. > > So, 3.0.18 is just fine, right? Yes. -- Kirill A. Shutemov