From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6B99C43387 for ; Wed, 26 Dec 2018 10:00:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 98760217D6 for ; Wed, 26 Dec 2018 10:00:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726713AbeLZKAm (ORCPT ); Wed, 26 Dec 2018 05:00:42 -0500 Received: from mga09.intel.com ([134.134.136.24]:3425 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726115AbeLZKAm (ORCPT ); Wed, 26 Dec 2018 05:00:42 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Dec 2018 02:00:41 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,400,1539673200"; d="scan'208";a="112107077" Received: from devel-ww.sh.intel.com ([10.239.48.119]) by fmsmga008.fm.intel.com with ESMTP; 26 Dec 2018 02:00:38 -0800 From: Wei Wang To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, pbonzini@redhat.com, ak@linux.intel.com, peterz@infradead.org Cc: kan.liang@intel.com, mingo@redhat.com, rkrcmar@redhat.com, like.xu@intel.com, wei.w.wang@intel.com, jannh@google.com, arei.gonglei@huawei.com Subject: [PATCH v4 00/10] Guest LBR Enabling Date: Wed, 26 Dec 2018 17:25:28 +0800 Message-Id: <1545816338-1171-1-git-send-email-wei.w.wang@intel.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Last Branch Recording (LBR) is a performance monitor unit (PMU) feature on Intel CPUs that captures branch related info. This patch series enables this feature to KVM guests. Here is a conclusion of the fundamental methods that we use: 1) the LBR feature is enabled per guest via QEMU setting of KVM_CAP_X86_GUEST_LBR; 2) the LBR stack is passed through to the guest for direct accesses after the guest's first access to any of the lbr related MSRs; 3) When the guest uses the LBR feature with the user callstack mode, the host will help save/resotre the LBR stack when the vCPU is scheduled out/in. ChangeLog: v3->v4: - perf/x86: - Patch 1: change the lbr msr variable type to "unsigned int"; - Patch 6: add a "no_counter" boolean attr to let callers explicitly tell the perf core to not allocate counters for the event; - Patch 7: change "cpuc->vcpu_lbr" from "boolean" to "u8", and add the PF_VCPU and is_kernel_event checks befoer setting it; - Patch 8: add the LBR_SELECT save/restore on vCPU switching; - Patch 9: move lbr_select_user_callstack to .h, instead of exporting it; - KVM/x86: - Patch 3: use "cap->args[0]" to enable/disable the lbr feature from userspace; - Patch 4: forbid the enabling the guest lbr when the host and guest see different lbr stack entries; - Patch 10: in guest_access_lbr_msr, pass through the lbr stack only when it has been passed through (i.e. add the check !vcpu->arch.lbr_used). previous: https://lkml.org/lkml/2018/9/20/507 Like Xu (1): KVM/x86/vPMU: Add APIs to support host save/restore the guest lbr stack Wei Wang (9): perf/x86: fix the variable type of the LBR MSRs perf/x86: add a function to get the lbr stack KVM/x86: KVM_CAP_X86_GUEST_LBR KVM/x86: intel_pmu_lbr_enable KVM/x86: expose MSR_IA32_PERF_CAPABILITIES to the guest perf/x86: no counter allocation support perf/x86: save/restore LBR_SELECT on vCPU switching perf/x86: function to check lbr user callstack mode KVM/x86/lbr: lazy save the guest lbr stack arch/x86/events/core.c | 12 +++ arch/x86/events/intel/lbr.c | 82 ++++++++--------- arch/x86/events/perf_event.h | 6 +- arch/x86/include/asm/kvm_host.h | 7 ++ arch/x86/include/asm/perf_event.h | 64 +++++++++++++ arch/x86/kvm/cpuid.c | 2 +- arch/x86/kvm/cpuid.h | 8 ++ arch/x86/kvm/pmu.c | 8 ++ arch/x86/kvm/pmu.h | 10 +++ arch/x86/kvm/pmu_intel.c | 183 ++++++++++++++++++++++++++++++++++++++ arch/x86/kvm/vmx.c | 147 ++++++++++++++++++++++++++++++ arch/x86/kvm/x86.c | 14 +++ include/linux/perf_event.h | 12 +++ include/uapi/linux/kvm.h | 1 + include/uapi/linux/perf_event.h | 3 +- kernel/events/core.c | 7 -- 16 files changed, 514 insertions(+), 52 deletions(-) -- 2.7.4