From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751347Ab1LHQLH (ORCPT ); Thu, 8 Dec 2011 11:11:07 -0500 Received: from imr4.ericy.com ([198.24.6.9]:56815 "EHLO imr4.ericy.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751220Ab1LHQLD (ORCPT ); Thu, 8 Dec 2011 11:11:03 -0500 Subject: Re: [PATCH 06/10] HWMON: Convert coretemp to x86 cpuid autoprobing From: Guenter Roeck Reply-To: guenter.roeck@ericsson.com To: Jean Delvare CC: Andi Kleen , "linux-kernel@vger.kernel.org" , Kay Sievers , "trenn@suse.de" , Andi Kleen , "fenghua.yu@intel.com" In-Reply-To: <20111208082402.3591123f@endymion.delvare> References: <1323304882-27953-1-git-send-email-andi@firstfloor.org> <1323304882-27953-7-git-send-email-andi@firstfloor.org> <20111208024001.GA4912@ericsson.com> <20111208082402.3591123f@endymion.delvare> Content-Type: text/plain; charset="UTF-8" Organization: Ericsson Date: Thu, 8 Dec 2011 08:09:29 -0800 Message-ID: <1323360569.2415.16.camel@groeck-laptop> MIME-Version: 1.0 X-Mailer: Evolution 2.32.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2011-12-08 at 02:24 -0500, Jean Delvare wrote: > Hi Andi, > > Thanks a lot for working on this. I wanted to give it a try long ago but > could never find the time. > > On Wed, 7 Dec 2011 18:40:01 -0800, Guenter Roeck wrote: > > Andi, > > > > On Wed, Dec 07, 2011 at 07:41:19PM -0500, Andi Kleen wrote: > > > From: Andi Kleen > > > > > > Use the new x86 cpuid autoprobe interface for the Intel coretemp > > > driver. > > > > > > Cc: fenghua.yu@intel.com > > > Cc: khali@linux-fr.org > > > Cc: guenter.roeck@ericsson.com > > > Signed-off-by: Andi Kleen > > > --- > > > drivers/hwmon/coretemp.c | 17 ++++++++++++++--- > > > 1 files changed, 14 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c > > > index 104b376..5de1579 100644 > > > --- a/drivers/hwmon/coretemp.c > > > +++ b/drivers/hwmon/coretemp.c > > > @@ -39,6 +39,7 @@ > > > #include > > > #include > > > #include > > > +#include > > > > > > #define DRVNAME "coretemp" > > > > > > @@ -756,13 +757,23 @@ static struct notifier_block coretemp_cpu_notifier __refdata = { > > > .notifier_call = coretemp_cpu_callback, > > > }; > > > > > > +static struct x86_cpu_id coretemp_ids[] = { > > Can't this be made const? > Unless I am missing something, the patchset would have to change to accept a const as parameter to x86_match_cpu(). > > > + { X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_DTS }, > > > + {} > > > +}; > > > +MODULE_DEVICE_TABLE(x86cpu, coretemp_ids); > > > + > > > static int __init coretemp_init(void) > > > { > > > int i, err = -ENODEV; > > > > > > - /* quick check if we run Intel */ > > > - if (cpu_data(0).x86_vendor != X86_VENDOR_INTEL) > > > - goto exit; > > > + /* > > > + * CPUID.06H.EAX[0] indicates whether the CPU has thermal > > > + * sensors. We check this bit only, all the early CPUs > > > + * without thermal sensors will be filtered out. > > > + */ > > > + if (!x86_match_cpu(coretemp_ids)) > > > + return -ENODEV; > > > > X86_FEATURE_DTS is checked elsewhere in the driver, in function get_core_online(). > > Can that check be removed ? > > Is it not possible in theory to mix a CPU with DTS and one without DTS > on the same system? There may be a reason why the DTS flag was checked > in get_core_online() (i.e. on a per-core basis) rather than in > coretemp_init(). I seem to recall that someone explicitly asked for it. > > To avoid any risk of regression, I wouldn't touch this part of the code. > Ok, makes sense. Thanks, Guenter