Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757081Ab1FPW2h (ORCPT ); Thu, 16 Jun 2011 18:28:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33235 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756133Ab1FPW2a (ORCPT ); Thu, 16 Jun 2011 18:28:30 -0400 From: Glauber Costa To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Rik van Riel , Jeremy Fitzhardinge , Peter Zijlstra , Avi Kivity , Anthony Liguori , Eric B Munson Subject: [PATCH v2 2/7] KVM-HDR: KVM Steal time implementation Date: Thu, 16 Jun 2011 18:20:51 -0400 Message-Id: <1308262856-5779-3-git-send-email-glommer@redhat.com> In-Reply-To: <1308262856-5779-1-git-send-email-glommer@redhat.com> References: <1308262856-5779-1-git-send-email-glommer@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3618 Lines: 100 To implement steal time, we need the hypervisor to pass the guest information about how much time was spent running other processes outside the VM. This is per-vcpu, and using the kvmclock structure for that is an abuse we decided not to make. In this patchset, I am introducing a new msr, KVM_MSR_STEAL_TIME, that holds the memory area address containing information about steal time This patch contains the headers for it. I am keeping it separate to facilitate backports to people who wants to backport the kernel part but not the hypervisor, or the other way around. Signed-off-by: Glauber Costa CC: Rik van Riel CC: Jeremy Fitzhardinge CC: Peter Zijlstra CC: Avi Kivity CC: Anthony Liguori CC: Eric B Munson --- Documentation/virtual/kvm/msr.txt | 33 +++++++++++++++++++++++++++++++++ arch/x86/include/asm/kvm_para.h | 9 +++++++++ 2 files changed, 42 insertions(+), 0 deletions(-) diff --git a/Documentation/virtual/kvm/msr.txt b/Documentation/virtual/kvm/msr.txt index d079aed..79c12a7 100644 --- a/Documentation/virtual/kvm/msr.txt +++ b/Documentation/virtual/kvm/msr.txt @@ -185,3 +185,36 @@ MSR_KVM_ASYNC_PF_EN: 0x4b564d02 Currently type 2 APF will be always delivered on the same vcpu as type 1 was, but guest should not rely on that. + +MSR_KVM_STEAL_TIME: 0x4b564d03 + + data: 64-byte alignment physical address of a memory area which must be + in guest RAM, plus an enable bit in bit 0. This memory is expected to + hold a copy of the following structure: + + struct kvm_steal_time { + __u64 steal; + __u32 version; + __u32 flags; + __u32 pad[6]; + } + + whose data will be filled in by the hypervisor periodically. Only one + write, or registration, is needed for each VCPU. The interval between + updates of this structure is arbitrary and implementation-dependent. + The hypervisor may update this structure at any time it sees fit until + anything with bit0 == 0 is written to it. Guest is required to make sure + this structure is initialized to zero. + + Fields have the following meanings: + + version: guest has to check version before and after grabbing + time information and check that they are both equal and even. + An odd version indicates an in-progress update. + + flags: At this point, always zero. May be used to indicate + changes in this structure in the future. + + steal: the amount of time in which this vCPU did not run, in + nanoseconds. + diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index d6cd79b..ac306c4 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -21,6 +21,7 @@ */ #define KVM_FEATURE_CLOCKSOURCE2 3 #define KVM_FEATURE_ASYNC_PF 4 +#define KVM_FEATURE_STEAL_TIME 5 /* The last 8 bits are used to indicate how to interpret the flags field * in pvclock structure. If no bits are set, all flags are ignored. @@ -35,6 +36,14 @@ #define MSR_KVM_WALL_CLOCK_NEW 0x4b564d00 #define MSR_KVM_SYSTEM_TIME_NEW 0x4b564d01 #define MSR_KVM_ASYNC_PF_EN 0x4b564d02 +#define MSR_KVM_STEAL_TIME 0x4b564d03 + +struct kvm_steal_time { + __u64 steal; + __u32 version; + __u32 flags; + __u32 pad[6]; +}; #define KVM_MAX_MMU_OP_BATCH 32 -- 1.7.3.4 -- 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/