Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759291Ab0GBRRx (ORCPT ); Fri, 2 Jul 2010 13:17:53 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:45459 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755262Ab0GBRRv convert rfc822-to-8bit (ORCPT ); Fri, 2 Jul 2010 13:17:51 -0400 MIME-Version: 1.0 In-Reply-To: <4C2CEF5D.8060609@redhat.com> References: <1277136847-13266-11-git-send-email-stefano@stabellini.net> <4C2CEF5D.8060609@redhat.com> From: Stefano Stabellini Date: Fri, 2 Jul 2010 18:17:29 +0100 Message-ID: Subject: Re: [PATCH 11/13] Use xen_vcpuop_clockevent, xen_clocksource and xen wallclock. To: ddutile@redhat.com Cc: linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com, Stefano.Stabellini@eu.citrix.com, sheng@linux.intel.com, jeremy@goop.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4020 Lines: 103 On Thu, Jul 1, 2010 at 8:41 PM, Don Dutile wrote: > stefano@stabellini.net wrote: >> From: Stefano Stabellini >> >> Use xen_vcpuop_clockevent instead of hpet and APIC timers as main >> clockevent device on all vcpus, use the xen wallclock time as wallclock >> instead of rtc and use xen_clocksource as clocksource. >> The pv clock algorithm needs to work correctly for the xen_clocksource >> and xen wallclock to be usable, only modern Xen versions offer a >> reliable pv clock in HVM guests (XENFEAT_hvm_safe_pvclock). >> >> Using the hpet as clocksource means a VMEXIT every time we read/write to >> the hpet mmio addresses, pvclock give us a better rating without >> VMEXITs. Same goes for the xen wallclock and xen_vcpuop_clockevent >> >> Signed-off-by: Stefano Stabellini >> --- >> ?arch/x86/xen/enlighten.c ? ? ? ? | ? 14 +-------- >> ?arch/x86/xen/suspend.c ? ? ? ? ? | ? ?4 ++ >> ?arch/x86/xen/time.c ? ? ? ? ? ? ?| ? 59 ++++++++++++++++++++++++++++++++++--- >> ?arch/x86/xen/xen-ops.h ? ? ? ? ? | ? ?7 +--- >> ?include/xen/interface/features.h | ? ?3 ++ >> ?5 files changed, 65 insertions(+), 22 deletions(-) >> >> diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c >> index 90bac21..bcd98a9 100644 >> --- a/arch/x86/xen/enlighten.c >> +++ b/arch/x86/xen/enlighten.c >> @@ -933,10 +933,6 @@ static const struct pv_init_ops xen_init_ops __initdata = { >> ? ? ? .patch = xen_patch, >> ?}; >> >> -static const struct pv_time_ops xen_time_ops __initdata = { >> - ? ? .sched_clock = xen_sched_clock, >> -}; >> - >> ?static const struct pv_cpu_ops xen_cpu_ops __initdata = { >> ? ? ? .cpuid = xen_cpuid, >> >> @@ -1074,7 +1070,6 @@ asmlinkage void __init xen_start_kernel(void) >> ? ? ? /* Install Xen paravirt ops */ >> ? ? ? pv_info = xen_info; >> ? ? ? pv_init_ops = xen_init_ops; >> - ? ? pv_time_ops = xen_time_ops; >> ? ? ? pv_cpu_ops = xen_cpu_ops; >> ? ? ? pv_apic_ops = xen_apic_ops; >> >> @@ -1082,13 +1077,7 @@ asmlinkage void __init xen_start_kernel(void) >> ? ? ? x86_init.oem.arch_setup = xen_arch_setup; >> ? ? ? x86_init.oem.banner = xen_banner; >> >> - ? ? x86_init.timers.timer_init = xen_time_init; >> - ? ? x86_init.timers.setup_percpu_clockev = x86_init_noop; >> - ? ? x86_cpuinit.setup_percpu_clockev = x86_init_noop; >> - >> - ? ? x86_platform.calibrate_tsc = xen_tsc_khz; >> - ? ? x86_platform.get_wallclock = xen_get_wallclock; >> - ? ? x86_platform.set_wallclock = xen_set_wallclock; >> + ? ? xen_init_time_ops(); >> >> ? ? ? /* >> ? ? ? ?* Set up some pagetable state before starting to set any ptes. >> @@ -1330,4 +1319,5 @@ void __init xen_hvm_guest_init(void) >> ? ? ? register_cpu_notifier(&xen_hvm_cpu_notifier); >> ? ? ? have_vcpu_info_placement = 0; >> ? ? ? x86_init.irqs.intr_init = xen_init_IRQ; >> + ? ? xen_hvm_init_time_ops(); >> ?} >> diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c >> index 6ff9665..0774c67 100644 >> --- a/arch/x86/xen/suspend.c >> +++ b/arch/x86/xen/suspend.c >> @@ -28,8 +28,12 @@ void xen_pre_suspend(void) >> >> ?void xen_hvm_post_suspend(int suspend_cancelled) >> ?{ >> + ? ? int cpu; >> ? ? ? xen_hvm_init_shared_info(); >> ? ? ? xen_callback_vector(); >> + ? ? for_each_online_cpu(cpu) { >> + ? ? ? ? ? ? xen_setup_runstate_info(cpu); >> + ? ? } >> ?} >> > > As I found out on older xen (non 'modern Xen version' ;-) ) > w/o XENFEAT_hvm_safe_pvclock, the above patch should look like: > > ? ? ? ?if (xen_feature(XENFEAT_hvm_safe_pvclock)) { > ? ? ? ? ? ? ? ?int cpu; > ? ? ? ? ? ? ? ?for_each_online_cpu(cpu) { > ? ? ? ? ? ? ? ? ? ? ? ?xen_setup_runstate_info(cpu); > ? ? ? ? ? ? ? ?} > ? ? ? ?} > Thank you for testing my series and for the patch, I'll include it in the next version. -- 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/