Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932818AbaLBSZb (ORCPT ); Tue, 2 Dec 2014 13:25:31 -0500 Received: from mga03.intel.com ([134.134.136.65]:18392 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932649AbaLBSZ3 (ORCPT ); Tue, 2 Dec 2014 13:25:29 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.07,502,1413270000"; d="scan'208";a="617433251" Date: Tue, 2 Dec 2014 10:24:02 -0800 From: Kristen Carlson Accardi To: Ethan Zhao Cc: , , , , , , , , , Subject: Re: [PATCH 2/2 V6] intel_pstate: add kernel parameter to force loading on Sun X86 servers. Message-ID: <20141202102402.09ea6017@kcaccard-desk.amr.corp.intel.com> In-Reply-To: <1417145777-21897-4-git-send-email-ethan.zhao@oracle.com> References: <1417145777-21897-1-git-send-email-ethan.zhao@oracle.com> <1417145777-21897-4-git-send-email-ethan.zhao@oracle.com> X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.24; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 28 Nov 2014 12:36:17 +0900 Ethan Zhao wrote: > To force loading on Oracle Sun X86 servers, provide one kernel command line > parameter > > intel_pstate = ora_force > > For those who be aware of the risk of no power capping capabily working and > try to get better performance with this driver. So, is this something you'd expect users to use on production systems, or is it just for debug? Thanks, Kristen > > Signed-off-by: Ethan Zhao > --- > v2: change to hardware vendor specific naming parameter. > v4: refine code and doc. > v5&v6: fix a typo in doc. > > Documentation/kernel-parameters.txt | 5 +++++ > drivers/cpufreq/intel_pstate.c | 6 +++++- > 2 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index 479f332..7d0983e 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -1446,6 +1446,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > disable > Do not enable intel_pstate as the default > scaling driver for the supported processors > + ora_force > + Force loading intel_pstate on Oracle Sun Servers(X86). > + only for those who be aware of the risk of no power capping > + capability working and try to get better performance with this > + driver. > > intremap= [X86-64, Intel-IOMMU] > on enable Interrupt Remapping (default) > diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c > index 1bb62ca..2654e13 100644 > --- a/drivers/cpufreq/intel_pstate.c > +++ b/drivers/cpufreq/intel_pstate.c > @@ -866,6 +866,7 @@ static struct cpufreq_driver intel_pstate_driver = { > }; > > static int __initdata no_load; > +static unsigned int ora_force; > > static int intel_pstate_msrs_not_valid(void) > { > @@ -1003,7 +1004,8 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) > case PSS: > return intel_pstate_no_acpi_pss(); > case PCC: > - return intel_pstate_has_acpi_ppc(); > + return intel_pstate_has_acpi_ppc() && > + (!ora_force); > } > } > > @@ -1078,6 +1080,8 @@ static int __init intel_pstate_setup(char *str) > > if (!strcmp(str, "disable")) > no_load = 1; > + if (!strcmp(str, "ora_force")) > + ora_force = 1; > return 0; > } > early_param("intel_pstate", intel_pstate_setup); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/