From nobody Mon Feb 9 17:22:44 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1571236630; cv=none; d=zoho.com; s=zohoarc; b=NBSc2MykWxNanzZ6hQ5AEebis5sZZ5IpK5EcaPUBKCTCF4+MyMIxx+kGO9bSCoC3Le2tHmDAeaWsOrs8haoc5yAM3wdt7v39T1p9qP8MG00kZ22VK1BCoRQby9NjTPcsDYVian4q9SEQx6VhcGkJL2+a7OvAgslEDoRmHiANKsU= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1571236630; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=bjPgRvM3FEBGI5BBaeFEAqrJkdolBhpc+7FM9CEwi6w=; b=FpuL2hxOkXCr+WjaqLlImfsSbI92ejapdagZBcSXv+9h9jERFZ4IvRHoNyn+P76QETj0dGmiMTJrIbcYTPsfZfDWBTs06eYbS9AFAf2dQqYteRGt8tz3HCTGPQbaynRM2tLN3u35G1mng/UfAyKSUPUu8Vbw09B2JolFF2/C45g= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 157123663045688.02732245557058; Wed, 16 Oct 2019 07:37:10 -0700 (PDT) Received: from localhost ([::1]:43450 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iKkQB-0007PB-EC for importer@patchew.org; Wed, 16 Oct 2019 10:37:03 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41750) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iKkNc-0005AW-FT for qemu-devel@nongnu.org; Wed, 16 Oct 2019 10:34:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iKkNa-0000k3-V8 for qemu-devel@nongnu.org; Wed, 16 Oct 2019 10:34:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37766) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iKkNX-0000iG-UU; Wed, 16 Oct 2019 10:34:20 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2AE7F8553A; Wed, 16 Oct 2019 14:34:19 +0000 (UTC) Received: from kamzik.brq.redhat.com (unknown [10.43.2.160]) by smtp.corp.redhat.com (Postfix) with ESMTP id ACF3E19C68; Wed, 16 Oct 2019 14:34:17 +0000 (UTC) From: Andrew Jones To: qemu-devel@nongnu.org, qemu-arm@nongnu.org Subject: [PATCH v1 3/5] target/arm/kvm: Implement cpu feature kvm-adjvtime Date: Wed, 16 Oct 2019 16:34:08 +0200 Message-Id: <20191016143410.5023-4-drjones@redhat.com> In-Reply-To: <20191016143410.5023-1-drjones@redhat.com> References: <20191016143410.5023-1-drjones@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Wed, 16 Oct 2019 14:34:19 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peter.maydell@linaro.org, richard.henderson@linaro.org, bijan.mottahedeh@oracle.com, maz@kernel.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" When kvm-adjvtime is enabled the guest's cntvct[_el0] won't count the time when the VM is stopped. That time is skipped by updating cntvoff[_el2] on each transition to vm_running using the current QEMU_CLOCK_VIRTUAL time. QEMU_CLOCK_VIRTUAL only ticks when the VM is running. This patch only provides the implementation. A subsequent patch will provide the CPU property allowing the feature to be enabled. Reported-by: Bijan Mottahedeh Suggested-by: Bijan Mottahedeh Signed-off-by: Andrew Jones Reviewed-by: Richard Henderson --- target/arm/cpu.h | 3 +++ target/arm/kvm.c | 32 ++++++++++++++++++++++++++++++++ target/arm/kvm32.c | 3 +++ target/arm/kvm64.c | 3 +++ target/arm/kvm_arm.h | 14 ++++++++++++++ 5 files changed, 55 insertions(+) diff --git a/target/arm/cpu.h b/target/arm/cpu.h index b3092e5213e6..7c07c7c5272e 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -821,6 +821,9 @@ struct ARMCPU { /* KVM init features for this CPU */ uint32_t kvm_init_features[7]; =20 + /* KVM CPU features */ + bool kvm_adjvtime; + /* Uniprocessor system with MP extensions */ bool mp_is_up; =20 diff --git a/target/arm/kvm.c b/target/arm/kvm.c index 5b82cefef608..373b868dc248 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -348,6 +348,18 @@ void kvm_arm_register_device(MemoryRegion *mr, uint64_= t devid, uint64_t group, memory_region_ref(kd->mr); } =20 +void kvm_arm_vm_state_change(void *opaque, int running, RunState state) +{ + CPUState *cs =3D opaque; + ARMCPU *cpu =3D ARM_CPU(cs); + + if (running) { + if (cpu->kvm_adjvtime) { + kvm_arm_set_virtual_time(cs); + } + } +} + static int compare_u64(const void *a, const void *b) { if (*(uint64_t *)a > *(uint64_t *)b) { @@ -579,6 +591,26 @@ int kvm_arm_sync_mpstate_to_qemu(ARMCPU *cpu) return 0; } =20 +void kvm_arm_set_virtual_time(CPUState *cs) +{ + uint64_t cnt; + struct kvm_one_reg reg =3D { + .id =3D KVM_REG_ARM_TIMER_CNT, + .addr =3D (uintptr_t)&cnt, + }; + int ret; + + cnt =3D muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL), + cpu_get_host_tick_frequency(), + NANOSECONDS_PER_SECOND); + + ret =3D kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, ®); + if (ret) { + error_report("Failed to set KVM_REG_ARM_TIMER_CNT"); + abort(); + } +} + int kvm_put_vcpu_events(ARMCPU *cpu) { CPUARMState *env =3D &cpu->env; diff --git a/target/arm/kvm32.c b/target/arm/kvm32.c index 32bf8d6757c4..3a8b437eef0b 100644 --- a/target/arm/kvm32.c +++ b/target/arm/kvm32.c @@ -16,6 +16,7 @@ #include "qemu-common.h" #include "cpu.h" #include "qemu/timer.h" +#include "sysemu/runstate.h" #include "sysemu/kvm.h" #include "kvm_arm.h" #include "internals.h" @@ -198,6 +199,8 @@ int kvm_arch_init_vcpu(CPUState *cs) return -EINVAL; } =20 + qemu_add_vm_change_state_handler(kvm_arm_vm_state_change, cs); + /* Determine init features for this CPU */ memset(cpu->kvm_init_features, 0, sizeof(cpu->kvm_init_features)); if (cpu->start_powered_off) { diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c index 666a81a5ce6f..d368189fbce6 100644 --- a/target/arm/kvm64.c +++ b/target/arm/kvm64.c @@ -23,6 +23,7 @@ #include "qemu/host-utils.h" #include "qemu/main-loop.h" #include "exec/gdbstub.h" +#include "sysemu/runstate.h" #include "sysemu/kvm.h" #include "sysemu/kvm_int.h" #include "kvm_arm.h" @@ -735,6 +736,8 @@ int kvm_arch_init_vcpu(CPUState *cs) return -EINVAL; } =20 + qemu_add_vm_change_state_handler(kvm_arm_vm_state_change, cs); + /* Determine init features for this CPU */ memset(cpu->kvm_init_features, 0, sizeof(cpu->kvm_init_features)); if (cpu->start_powered_off) { diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h index 8e14d400e8ab..3bb7e331aa06 100644 --- a/target/arm/kvm_arm.h +++ b/target/arm/kvm_arm.h @@ -232,6 +232,16 @@ void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *= map); */ void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu); =20 +/** + * void kvm_arm_set_virtual_time: + * @cs: CPUState + * + * Sets the guest's virtual counter offset to the difference of the host's + * current time and QEMU's QEMU_CLOCK_VIRTUAL time. This allows the + * guest's virtual counter to only reflect VM running time. + */ +void kvm_arm_set_virtual_time(CPUState *cs); + /** * kvm_arm_aarch32_supported: * @cs: CPUState @@ -288,6 +298,8 @@ void kvm_arm_pmu_set_irq(CPUState *cs, int irq); void kvm_arm_pmu_init(CPUState *cs); int kvm_arm_set_irq(int cpu, int irqtype, int irq, int level); =20 +void kvm_arm_vm_state_change(void *opaque, int running, RunState state); + #else =20 static inline void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu) @@ -324,6 +336,8 @@ static inline int kvm_arm_vgic_probe(void) return 0; } =20 +static inline void kvm_arm_set_virtual_time(CPUState *cs) {} + static inline void kvm_arm_pmu_set_irq(CPUState *cs, int irq) {} static inline void kvm_arm_pmu_init(CPUState *cs) {} =20 --=20 2.21.0