From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758787Ab2C1WJ2 (ORCPT ); Wed, 28 Mar 2012 18:09:28 -0400 Received: from smtp.tele.fi ([192.89.123.25]:39964 "EHLO vulpes-int.media.sonera.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1758287Ab2C1WJ1 (ORCPT ); Wed, 28 Mar 2012 18:09:27 -0400 X-Greylist: delayed 2975 seconds by postgrey-1.27 at vger.kernel.org; Wed, 28 Mar 2012 18:09:27 EDT X-Originating-Ip: [194.89.68.22] Date: Thu, 29 Mar 2012 00:19:47 +0300 From: Pasi =?iso-8859-1?Q?K=E4rkk=E4inen?= To: Konrad Rzeszutek Wilk Cc: Jesse Barnes , Konrad Rzeszutek Wilk , mjg@redhat.com, linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com Subject: Re: [Xen-devel] Stop the continuous flood of (XEN) traps.c:2432:d0 Domain attempted WRMSR .. Message-ID: <20120328211947.GT12984@reaktio.net> References: <20120203180952.GP12984@reaktio.net> <20120203185527.GA9290@phenom.dumpdata.com> <20120205194413.GR12984@reaktio.net> <20120209212147.GE14007@andromeda.dapyr.net> <20120209132715.2d1c0c9f@jbarnes-desktop> <20120328202907.GA1784@phenom.dumpdata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120328202907.GA1784@phenom.dumpdata.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 28, 2012 at 04:29:07PM -0400, Konrad Rzeszutek Wilk wrote: > > > > > > Jesse, and Matthew, > > > > > > Is there a way to make the intel_ips.c driver be in a "low-power" state? > > > > > > My first thought about fixing this was that we could allow the > > > hypervisor to allow those RDMSR but the Linux kernel has no power to > > > actually influence the power management (as the hypervisor is in charge > > > of that) - so would the driver be capable of just sitting back and > > > not influencing the CPU? > > > > Yeah it's easy enough to turn off or disable. But it doesn't currently > > export any knobs for controlling behavior. I don't have any issue with > > exposing some though... > > Pasi, > > Could you test the two patches independetly of each other? Meaning > test the Linux one without the Xen one, and vice-versa. > Sure, I'll give it a try during the weekend when I'm able to access the box in question. Thanks! -- Pasi > diff --git a/drivers/platform/x86/intel_ips.c b/drivers/platform/x86/intel_ips.c > index 88a98cf..7276831 100644 > --- a/drivers/platform/x86/intel_ips.c > +++ b/drivers/platform/x86/intel_ips.c > @@ -1407,6 +1407,10 @@ static struct ips_mcp_limits *ips_detect_cpu(struct ips_driver *ips) > } > > rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_power); > + if (turbo_power == 0) { > + ips->turbo_toggle_allowed = false; > + return NULL; > + } > tdp = turbo_power & TURBO_TDP_MASK; > > /* Sanity check TDP against CPU */ > diff -r 8e2690dbec49 xen/arch/x86/traps.c > --- a/xen/arch/x86/traps.c Sat Mar 24 13:13:49 2012 -0400 > +++ b/xen/arch/x86/traps.c Wed Mar 28 16:27:31 2012 -0400 > @@ -1746,7 +1746,8 @@ void (*pv_post_outb_hook)(unsigned int p > static inline uint64_t guest_misc_enable(uint64_t val) > { > val &= ~(MSR_IA32_MISC_ENABLE_PERF_AVAIL | > - MSR_IA32_MISC_ENABLE_MONITOR_ENABLE); > + MSR_IA32_MISC_ENABLE_MONITOR_ENABLE | > + MSR_IA32_MISC_ENABLE_TURBO); > val |= MSR_IA32_MISC_ENABLE_BTS_UNAVAIL | > MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL | > MSR_IA32_MISC_ENABLE_XTPR_DISABLE; > diff -r 8e2690dbec49 xen/include/asm-x86/msr-index.h > --- a/xen/include/asm-x86/msr-index.h Sat Mar 24 13:13:49 2012 -0400 > +++ b/xen/include/asm-x86/msr-index.h Wed Mar 28 16:27:31 2012 -0400 > @@ -327,6 +327,7 @@ > #define MSR_IA32_MISC_ENABLE_MONITOR_ENABLE (1<<18) > #define MSR_IA32_MISC_ENABLE_LIMIT_CPUID (1<<22) > #define MSR_IA32_MISC_ENABLE_XTPR_DISABLE (1<<23) > +#define MSR_IA32_MISC_ENABLE_TURBO (1<<38) > > #define MSR_IA32_TSC_DEADLINE 0x000006E0 > #define MSR_IA32_ENERGY_PERF_BIAS 0x000001b0