From patchwork Fri Dec 4 01:18:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Woodhouse X-Patchwork-Id: 11950337 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 72D0EC1B087 for ; Fri, 4 Dec 2020 01:20:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3AE5A224DF for ; Fri, 4 Dec 2020 01:20:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388470AbgLDBUS (ORCPT ); Thu, 3 Dec 2020 20:20:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388403AbgLDBUQ (ORCPT ); Thu, 3 Dec 2020 20:20:16 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 768E7C08E864 for ; Thu, 3 Dec 2020 17:18:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=QFshErqJ3OMjFsS38xYCjMiz9Q5VQIfk1sihj7iHIMg=; b=cJ+kVFytszYom/UnhE4bsh+riM 3kvkrDJpIbu6syAZX/S21pj5X0b4ZfSy+NfkLnmjGlfjsKE8dLZQi8IIQsTcHGWSiRd9m0IVZAyik jZhUMLcvJCNs8JOSQNNRWfGnT9+Dr1BxKg+C6XxzwRwzpQV6ROztARoXVkkhIyTiyIs0WzAtq+O26 wmrDv/QM0XYfYOAG15CayAk4KmtagpRBeLCMhV+mSu0FGIp1RBRN0lrJovQx/jy0ihXA27xyh5EoX tEhTXiX5iG2R1hl1TlOcn6bthw1Li5SMbQdVqlpyNKMjDkwdeleC/gU2QAPIGexp0LimN1SU1c90W m6LS+llw==; Received: from i7.infradead.org ([2001:8b0:10b:1:21e:67ff:fecb:7a92]) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kkzkK-0004Kd-Ri; Fri, 04 Dec 2020 01:18:54 +0000 Received: from dwoodhou by i7.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1kkzkK-00CSA8-C7; Fri, 04 Dec 2020 01:18:52 +0000 From: David Woodhouse To: kvm@vger.kernel.org Cc: Paolo Bonzini , Ankur Arora , Joao Martins , Boris Ostrovsky , Sean Christopherson Subject: [PATCH 09/15] KVM: x86/xen: setup pvclock updates Date: Fri, 4 Dec 2020 01:18:42 +0000 Message-Id: <20201204011848.2967588-10-dwmw2@infradead.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201204011848.2967588-1-dwmw2@infradead.org> References: <20201204011848.2967588-1-dwmw2@infradead.org> MIME-Version: 1.0 Sender: David Woodhouse X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joao Martins This means when we set shared_info page GPA, and request a master clock update. This will trigger all vcpus to update their respective shared pvclock data with guests. We follow a similar approach as Hyper-V and KVM and adjust it accordingly. Note however that Xen differs a little on how pvclock pages are set up. Specifically KVM assumes 4KiB page alignment and pvclock data starts in the beginning of the page. Whereas Xen you can place that information anywhere in the page. Signed-off-by: Joao Martins Signed-off-by: David Woodhouse --- arch/x86/kvm/x86.c | 2 ++ arch/x86/kvm/xen.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++ arch/x86/kvm/xen.h | 1 + 3 files changed, 53 insertions(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 156ce72ba9bf..daf4a1f26811 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2719,6 +2719,8 @@ static int kvm_guest_time_update(struct kvm_vcpu *v) if (vcpu->pv_time_enabled) kvm_setup_pvclock_page(v); + if (ka->xen.shinfo) + kvm_xen_setup_pvclock_page(v); if (v == kvm_get_vcpu(v->kvm, 0)) kvm_hv_setup_tsc_page(v->kvm, &vcpu->hv_clock); return 0; diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c index c156ed1ef972..c0fd54f1c121 100644 --- a/arch/x86/kvm/xen.c +++ b/arch/x86/kvm/xen.c @@ -55,9 +55,59 @@ static int kvm_xen_shared_info_init(struct kvm *kvm, gfn_t gfn) if (ret) return ret; + kvm_make_all_cpus_request(kvm, KVM_REQ_MASTERCLOCK_UPDATE); + return 0; } +void kvm_xen_setup_pvclock_page(struct kvm_vcpu *v) +{ + struct kvm_vcpu_arch *vcpu = &v->arch; + struct pvclock_vcpu_time_info *guest_hv_clock; + unsigned int offset; + + if (v->vcpu_id >= MAX_VIRT_CPUS) + return; + + BUILD_BUG_ON(offsetof(struct pvclock_vcpu_time_info, version) != 0); + BUILD_BUG_ON(offsetof(struct shared_info, vcpu_info) != 0); + BUILD_BUG_ON(offsetof(struct compat_shared_info, vcpu_info) != 0); + BUILD_BUG_ON(sizeof(struct vcpu_info) != sizeof(struct compat_vcpu_info)); + BUILD_BUG_ON(offsetof(struct vcpu_info, time) != + offsetof(struct compat_vcpu_info, time)); + + offset = v->vcpu_id * sizeof(struct vcpu_info); + offset += offsetof(struct vcpu_info, time); + + guest_hv_clock = v->kvm->arch.xen.shinfo + offset; + + if (guest_hv_clock->version & 1) + ++guest_hv_clock->version; /* first time write, random junk */ + + vcpu->hv_clock.version = guest_hv_clock->version + 1; + guest_hv_clock->version = vcpu->hv_clock.version; + + smp_wmb(); + + /* retain PVCLOCK_GUEST_STOPPED if set in guest copy */ + vcpu->hv_clock.flags |= (guest_hv_clock->flags & PVCLOCK_GUEST_STOPPED); + + if (vcpu->pvclock_set_guest_stopped_request) { + vcpu->hv_clock.flags |= PVCLOCK_GUEST_STOPPED; + vcpu->pvclock_set_guest_stopped_request = false; + } + + trace_kvm_pvclock_update(v->vcpu_id, &vcpu->hv_clock); + + *guest_hv_clock = vcpu->hv_clock; + + smp_wmb(); + + vcpu->hv_clock.version++; + + guest_hv_clock->version = vcpu->hv_clock.version; +} + int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data) { int r = -ENOENT; diff --git a/arch/x86/kvm/xen.h b/arch/x86/kvm/xen.h index 870ac7197a3a..0b6bfe4ee108 100644 --- a/arch/x86/kvm/xen.h +++ b/arch/x86/kvm/xen.h @@ -9,6 +9,7 @@ #ifndef __ARCH_X86_KVM_XEN_H__ #define __ARCH_X86_KVM_XEN_H__ +void kvm_xen_setup_pvclock_page(struct kvm_vcpu *vcpu); int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data); int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data); int kvm_xen_hypercall(struct kvm_vcpu *vcpu);