| Message ID | 20200805091640.11134-6-drjones@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | hw/arm/virt: Introduce kvm-steal-time | expand |
Drew, On 8/5/20 11:16 AM, Andrew Jones wrote: > We add the kvm-steal-time CPU property and implement it for machvirt. > A tiny bit of refactoring was also done to allow pmu and pvtime to > use the same vcpu device helper functions. > > Signed-off-by: Andrew Jones <drjones@redhat.com> > --- > docs/system/arm/cpu-features.rst | 11 +++++ > hw/arm/virt.c | 43 ++++++++++++++++-- > include/hw/arm/virt.h | 5 +++ > target/arm/cpu.c | 10 +++++ > target/arm/cpu.h | 4 ++ > target/arm/kvm.c | 20 +++++++++ > target/arm/kvm32.c | 5 +++ > target/arm/kvm64.c | 77 +++++++++++++++++++++++++++++--- > target/arm/kvm_arm.h | 30 +++++++++++++ > target/arm/monitor.c | 2 +- > tests/qtest/arm-cpu-features.c | 25 +++++++++-- > 11 files changed, 219 insertions(+), 13 deletions(-) > > diff --git a/docs/system/arm/cpu-features.rst b/docs/system/arm/cpu-features.rst > index 2d5c06cd016b..35196a6b759d 100644 > --- a/docs/system/arm/cpu-features.rst > +++ b/docs/system/arm/cpu-features.rst > @@ -200,6 +200,17 @@ the list of KVM VCPU features and their descriptions. > adjustment, also restoring the legacy (pre-5.0) > behavior. > > + kvm-steal-time Since v5.2, kvm-steal-time is enabled by > + default when KVM is enabled, the feature is > + supported, and the guest is 64-bit. > + > + When kvm-steal-time is enabled a 64-bit guest > + can account for time its CPUs were not running > + due to the host not scheduling the corresponding > + VCPU threads. The accounting statistics may > + influence the guest scheduler behavior and/or be > + exposed to the guest userspace. > + > SVE CPU Properties > ================== > > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > index 6797eb397a7a..12efc2f095cb 100644 > --- a/hw/arm/virt.c > +++ b/hw/arm/virt.c > @@ -151,6 +151,7 @@ static const MemMapEntry base_memmap[] = { > [VIRT_PCDIMM_ACPI] = { 0x09070000, MEMORY_HOTPLUG_IO_LEN }, > [VIRT_ACPI_GED] = { 0x09080000, ACPI_GED_EVT_SEL_LEN }, > [VIRT_NVDIMM_ACPI] = { 0x09090000, NVDIMM_ACPI_IO_LEN}, > + [VIRT_PVTIME] = { 0x090a0000, 0x00010000 }, > [VIRT_MMIO] = { 0x0a000000, 0x00000200 }, > /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */ > [VIRT_PLATFORM_BUS] = { 0x0c000000, 0x02000000 }, > @@ -1666,15 +1667,39 @@ static void finalize_gic_version(VirtMachineState *vms) > * virt_cpu_post_init() must be called after the CPUs have > * been realized and the GIC has been created. > */ > -static void virt_cpu_post_init(VirtMachineState *vms) > +static void virt_cpu_post_init(VirtMachineState *vms, int max_cpus, > + MemoryRegion *sysmem) > { > - bool aarch64, pmu; > + bool aarch64, pmu, steal_time; > CPUState *cpu; > > aarch64 = object_property_get_bool(OBJECT(first_cpu), "aarch64", NULL); > pmu = object_property_get_bool(OBJECT(first_cpu), "pmu", NULL); > + steal_time = object_property_get_bool(OBJECT(first_cpu), > + "kvm-steal-time", NULL); > > if (kvm_enabled()) {> + hwaddr pvtime_reg_base = vms->memmap[VIRT_PVTIME].base; > + hwaddr pvtime_reg_size = vms->memmap[VIRT_PVTIME].size; > + > + if (steal_time) { > + MemoryRegion *pvtime = g_new(MemoryRegion, 1); > + hwaddr pvtime_size = max_cpus * PVTIME_SIZE_PER_CPU; > + > + /* The memory region size must be a multiple of host page size. */ > + pvtime_size = REAL_HOST_PAGE_ALIGN(pvtime_size); > + > + if (pvtime_size > pvtime_reg_size) { > + error_report("pvtime requires a %ld byte memory region for " > + "%d CPUs, but only %ld has been reserved", > + pvtime_size, max_cpus, pvtime_reg_size); > + exit(1); > + } > + > + memory_region_init_ram(pvtime, NULL, "pvtime", pvtime_size, NULL); > + memory_region_add_subregion(sysmem, pvtime_reg_base, pvtime); > + } > + > CPU_FOREACH(cpu) { > if (pmu) { > assert(arm_feature(&ARM_CPU(cpu)->env, ARM_FEATURE_PMU)); > @@ -1683,6 +1708,10 @@ static void virt_cpu_post_init(VirtMachineState *vms) > } > kvm_arm_pmu_init(cpu); > } > + if (steal_time) { > + kvm_arm_pvtime_init(cpu, pvtime_reg_base + > + cpu->cpu_index * PVTIME_SIZE_PER_CPU); > + } > } > } else { > if (aarch64 && vms->highmem) { > @@ -1853,6 +1882,11 @@ static void machvirt_init(MachineState *machine) > object_property_set_bool(cpuobj, "kvm-no-adjvtime", true, NULL); > } > > + if (vmc->no_kvm_steal_time && > + object_property_find(cpuobj, "kvm-steal-time", NULL)) { > + object_property_set_bool(cpuobj, "kvm-steal-time", false, NULL); > + } > + > if (vmc->no_pmu && object_property_find(cpuobj, "pmu", NULL)) { > object_property_set_bool(cpuobj, "pmu", false, NULL); > } > @@ -1924,7 +1958,7 @@ static void machvirt_init(MachineState *machine) > > create_gic(vms); > > - virt_cpu_post_init(vms); > + virt_cpu_post_init(vms, possible_cpus->len, sysmem); > > fdt_add_pmu_nodes(vms); > > @@ -2566,8 +2600,11 @@ DEFINE_VIRT_MACHINE_AS_LATEST(5, 2) > > static void virt_machine_5_1_options(MachineClass *mc) > { > + VirtMachineClass *vmc = VIRT_MACHINE_CLASS(OBJECT_CLASS(mc)); > + > virt_machine_5_2_options(mc); > compat_props_add(mc->compat_props, hw_compat_5_1, hw_compat_5_1_len); > + vmc->no_kvm_steal_time = true; > } > DEFINE_VIRT_MACHINE(5, 1) > > diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h > index dff67e1bef03..5fb43a009f7a 100644 > --- a/include/hw/arm/virt.h > +++ b/include/hw/arm/virt.h > @@ -53,6 +53,9 @@ > > #define PPI(irq) ((irq) + 16) > > +/* See Linux kernel arch/arm64/include/asm/pvclock-abi.h */ > +#define PVTIME_SIZE_PER_CPU 64 > + > enum { > VIRT_FLASH, > VIRT_MEM, > @@ -80,6 +83,7 @@ enum { > VIRT_PCDIMM_ACPI, > VIRT_ACPI_GED, > VIRT_NVDIMM_ACPI, > + VIRT_PVTIME, > VIRT_LOWMEMMAP_LAST, > }; > > @@ -126,6 +130,7 @@ typedef struct { > bool no_ged; /* Machines < 4.2 has no support for ACPI GED device */ > bool kvm_no_adjvtime; > bool acpi_expose_flash; > + bool no_kvm_steal_time; > } VirtMachineClass; > > typedef struct { > diff --git a/target/arm/cpu.c b/target/arm/cpu.c > index 111579554fb9..866d0a9fb146 100644 > --- a/target/arm/cpu.c > +++ b/target/arm/cpu.c > @@ -1308,6 +1308,16 @@ void arm_cpu_finalize_features(ARMCPU *cpu, Error **errp) > return; > } > } > + > + if (kvm_enabled()) { > +#ifdef TARGET_AARCH64 > + kvm_arm_steal_time_finalize(cpu, &local_err); > + if (local_err != NULL) { > + error_propagate(errp, local_err); > + return; > + } > +#endif > + } > } > > static void arm_cpu_realizefn(DeviceState *dev, Error **errp) > diff --git a/target/arm/cpu.h b/target/arm/cpu.h > index 9e8ed423ea1d..a4d4cb640c77 100644 > --- a/target/arm/cpu.h > +++ b/target/arm/cpu.h > @@ -24,6 +24,7 @@ > #include "hw/registerfields.h" > #include "cpu-qom.h" > #include "exec/cpu-defs.h" > +#include "qapi/qapi-types-common.h" > > /* ARM processors have a weak memory model */ > #define TCG_GUEST_DEFAULT_MO (0) > @@ -859,6 +860,9 @@ struct ARMCPU { > bool kvm_vtime_dirty; > uint64_t kvm_vtime; > > + /* KVM steal time */ > + OnOffAuto kvm_steal_time; > + > /* Uniprocessor system with MP extensions */ > bool mp_is_up; > > diff --git a/target/arm/kvm.c b/target/arm/kvm.c > index 8bb7318378b5..093a290453f6 100644 > --- a/target/arm/kvm.c > +++ b/target/arm/kvm.c > @@ -192,6 +192,18 @@ static void kvm_no_adjvtime_set(Object *obj, bool value, Error **errp) > ARM_CPU(obj)->kvm_adjvtime = !value; > } > > +#ifdef TARGET_AARCH64 > +static bool kvm_steal_time_get(Object *obj, Error **errp) > +{ > + return ARM_CPU(obj)->kvm_steal_time != ON_OFF_AUTO_OFF; > +} > + > +static void kvm_steal_time_set(Object *obj, bool value, Error **errp) > +{ > + ARM_CPU(obj)->kvm_steal_time = value ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF; > +} > +#endif > + > /* KVM VCPU properties should be prefixed with "kvm-". */ > void kvm_arm_add_vcpu_properties(Object *obj) > { > @@ -207,6 +219,14 @@ void kvm_arm_add_vcpu_properties(Object *obj) > "the virtual counter. VM stopped time " > "will be counted."); > } > + > +#ifdef TARGET_AARCH64 > + cpu->kvm_steal_time = ON_OFF_AUTO_AUTO; > + object_property_add_bool(obj, "kvm-steal-time", kvm_steal_time_get, > + kvm_steal_time_set); > + object_property_set_description(obj, "kvm-steal-time", > + "Set off to disable KVM steal time."); > +#endif > } > > bool kvm_arm_pmu_supported(void) > diff --git a/target/arm/kvm32.c b/target/arm/kvm32.c > index 0af46b41c847..d3f3195077fa 100644 > --- a/target/arm/kvm32.c > +++ b/target/arm/kvm32.c > @@ -560,6 +560,11 @@ void kvm_arm_pmu_init(CPUState *cs) > qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__); > } > > +void kvm_arm_pvtime_init(CPUState *cs, uint64_t ipa) > +{ > + qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__); > +} > + > #define ARM_REG_DFSR ARM_CP15_REG32(0, 5, 0, 0) > #define ARM_REG_TTBCR ARM_CP15_REG32(0, 2, 0, 2) > /* > diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c > index 116923790550..4de1eeb723ac 100644 > --- a/target/arm/kvm64.c > +++ b/target/arm/kvm64.c > @@ -17,6 +17,7 @@ > #include <linux/kvm.h> > > #include "qemu-common.h" > +#include "qapi/error.h" > #include "cpu.h" > #include "qemu/timer.h" > #include "qemu/error-report.h" > @@ -398,19 +399,20 @@ static CPUWatchpoint *find_hw_watchpoint(CPUState *cpu, target_ulong addr) > return NULL; > } > > -static bool kvm_arm_pmu_set_attr(CPUState *cs, struct kvm_device_attr *attr) > +static bool kvm_arm_set_device_attr(CPUState *cs, struct kvm_device_attr *attr, > + const char *name) > { > int err; > > err = kvm_vcpu_ioctl(cs, KVM_HAS_DEVICE_ATTR, attr); > if (err != 0) { > - error_report("PMU: KVM_HAS_DEVICE_ATTR: %s", strerror(-err)); > + error_report("%s: KVM_HAS_DEVICE_ATTR: %s", name, strerror(-err)); > return false; > } > > err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, attr); > if (err != 0) { > - error_report("PMU: KVM_SET_DEVICE_ATTR: %s", strerror(-err)); > + error_report("%s: KVM_SET_DEVICE_ATTR: %s", name, strerror(-err)); > return false; > } > > @@ -427,7 +429,7 @@ void kvm_arm_pmu_init(CPUState *cs) > if (!ARM_CPU(cs)->has_pmu) { > return; > } > - if (!kvm_arm_pmu_set_attr(cs, &attr)) { > + if (!kvm_arm_set_device_attr(cs, &attr, "PMU")) { > error_report("failed to init PMU"); > abort(); > } > @@ -444,12 +446,29 @@ void kvm_arm_pmu_set_irq(CPUState *cs, int irq) > if (!ARM_CPU(cs)->has_pmu) { > return; > } > - if (!kvm_arm_pmu_set_attr(cs, &attr)) { > + if (!kvm_arm_set_device_attr(cs, &attr, "PMU")) { > error_report("failed to set irq for PMU"); > abort(); > } > } > > +void kvm_arm_pvtime_init(CPUState *cs, uint64_t ipa) > +{ > + struct kvm_device_attr attr = { > + .group = KVM_ARM_VCPU_PVTIME_CTRL, > + .attr = KVM_ARM_VCPU_PVTIME_IPA, > + .addr = (uint64_t)&ipa, > + }; > + > + if (ARM_CPU(cs)->kvm_steal_time == ON_OFF_AUTO_OFF) { > + return; > + } > + if (!kvm_arm_set_device_attr(cs, &attr, "PVTIME IPA")) { > + error_report("failed to init PVTIME IPA"); > + abort(); > + } > +} > + > static int read_sys_reg32(int fd, uint32_t *pret, uint64_t id) > { > uint64_t ret; > @@ -652,6 +671,54 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf) > return true; > } > > +void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp) > +{ > + static bool has_steal_time; > + static bool probed; > + int fdarray[3]; > + > + if (!probed) { > + probed = true; > + if (kvm_check_extension(kvm_state, KVM_CAP_VCPU_ATTRIBUTES)) { > + if (!kvm_arm_create_scratch_host_vcpu(NULL, fdarray, NULL)) { > + error_report("Failed to create scratch VCPU"); > + abort(); > + } > + > + has_steal_time = kvm_device_check_attr(fdarray[2], > + KVM_ARM_VCPU_PVTIME_CTRL, > + KVM_ARM_VCPU_PVTIME_IPA); > + > + kvm_arm_destroy_scratch_host_vcpu(fdarray); > + } > + } > + > + if (cpu->kvm_steal_time == ON_OFF_AUTO_AUTO) { > + if (!has_steal_time || !arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) { > + cpu->kvm_steal_time = ON_OFF_AUTO_OFF; > + } else { > + cpu->kvm_steal_time = ON_OFF_AUTO_ON; > + } > + } else if (cpu->kvm_steal_time == ON_OFF_AUTO_ON) { > + if (!has_steal_time) { > + error_setg(errp, "'kvm-steal-time' cannot be enabled " > + "on this host"); > + return; > + } else if (!arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) { > + /* > + * DEN0057A chapter 2 says "This specification only covers > + * systems in which the Execution state of the hypervisor > + * as well as EL1 of virtual machines is AArch64.". And, > + * to ensure that, the smc/hvc calls are only specified as > + * smc64/hvc64. > + */ > + error_setg(errp, "'kvm-steal-time' cannot be enabled " > + "for AArch32 guests"); > + return; > + } > + } > +} > + > bool kvm_arm_aarch32_supported(void) > { > return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL1_32BIT); > diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h > index 0da00eb6b20c..4a8969505967 100644 > --- a/target/arm/kvm_arm.h > +++ b/target/arm/kvm_arm.h > @@ -267,6 +267,16 @@ void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu); > */ > void kvm_arm_add_vcpu_properties(Object *obj); > > +/** > + * kvm_arm_steal_time_finalize: > + * @cpu: ARMCPU for which to finalize kvm-steal-time > + * @errp: Pointer to Error* for error propagation > + * > + * Validate the kvm-steal-time property selection and set its default > + * based on KVM support and guest configuration. > + */ > +void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp); > + > /** > * kvm_arm_aarch32_supported: > * > @@ -340,6 +350,16 @@ int kvm_arm_vgic_probe(void); > > void kvm_arm_pmu_set_irq(CPUState *cs, int irq); > void kvm_arm_pmu_init(CPUState *cs); > + > +/** > + * kvm_arm_pvtime_init: > + * @cs: CPUState > + * @ipa: Per-vcpu guest physical base address of the pvtime structures > + * > + * Initializes PVTIME for the VCPU, setting the PVTIME IPA to @ipa. > + */ > +void kvm_arm_pvtime_init(CPUState *cs, uint64_t ipa); > + > int kvm_arm_set_irq(int cpu, int irqtype, int irq, int level); > > #else > @@ -393,6 +413,16 @@ static inline void kvm_arm_pmu_init(CPUState *cs) > g_assert_not_reached(); > } > > +static inline void kvm_arm_pvtime_init(CPUState *cs, uint64_t ipa) > +{ > + g_assert_not_reached(); > +} > + > +static inline void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp) > +{ > + g_assert_not_reached(); > +} > + > static inline void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map) > { > g_assert_not_reached(); > diff --git a/target/arm/monitor.c b/target/arm/monitor.c > index ba6e01abd037..bd3590604a71 100644 > --- a/target/arm/monitor.c > +++ b/target/arm/monitor.c > @@ -103,7 +103,7 @@ static const char *cpu_model_advertised_features[] = { > "sve128", "sve256", "sve384", "sve512", > "sve640", "sve768", "sve896", "sve1024", "sve1152", "sve1280", > "sve1408", "sve1536", "sve1664", "sve1792", "sve1920", "sve2048", > - "kvm-no-adjvtime", > + "kvm-no-adjvtime", "kvm-steal-time", > NULL > }; > > diff --git a/tests/qtest/arm-cpu-features.c b/tests/qtest/arm-cpu-features.c > index f7e062c1891e..91b181f38268 100644 > --- a/tests/qtest/arm-cpu-features.c > +++ b/tests/qtest/arm-cpu-features.c > @@ -452,6 +452,7 @@ static void test_query_cpu_model_expansion(const void *data) > assert_set_feature(qts, "max", "pmu", true); > > assert_has_not_feature(qts, "max", "kvm-no-adjvtime"); > + assert_has_not_feature(qts, "max", "kvm-steal-time"); > > if (g_str_equal(qtest_get_arch(), "aarch64")) { > assert_has_feature_enabled(qts, "max", "aarch64"); > @@ -493,6 +494,7 @@ static void test_query_cpu_model_expansion_kvm(const void *data) > assert_set_feature(qts, "host", "kvm-no-adjvtime", false); > > if (g_str_equal(qtest_get_arch(), "aarch64")) { > + bool kvm_supports_steal_time; > bool kvm_supports_sve; > char max_name[8], name[8]; > uint32_t max_vq, vq; > @@ -500,6 +502,10 @@ static void test_query_cpu_model_expansion_kvm(const void *data) > QDict *resp; > char *error; > > + assert_error(qts, "cortex-a15", > + "We cannot guarantee the CPU type 'cortex-a15' works " > + "with KVM on this host", NULL); > + > assert_has_feature_enabled(qts, "host", "aarch64"); > > /* Enabling and disabling pmu should always work. */ > @@ -507,16 +513,26 @@ static void test_query_cpu_model_expansion_kvm(const void *data) > assert_set_feature(qts, "host", "pmu", false); > assert_set_feature(qts, "host", "pmu", true); > > - assert_error(qts, "cortex-a15", > - "We cannot guarantee the CPU type 'cortex-a15' works " > - "with KVM on this host", NULL); > - > + /* > + * Some features would be enabled by default, but they're disabled > + * because this instance of KVM doesn't support them. Test that the > + * features are present, and, when enabled, issue further tests. > + */ > + assert_has_feature(qts, "host", "kvm-steal-time"); > assert_has_feature(qts, "host", "sve"); > + > resp = do_query_no_props(qts, "host"); > + kvm_supports_steal_time = resp_get_feature(resp, "kvm-steal-time"); > kvm_supports_sve = resp_get_feature(resp, "sve"); > vls = resp_get_sve_vls(resp); > qobject_unref(resp); > > + if (kvm_supports_steal_time) { > + /* If we have steal-time then we should be able to toggle it. */ > + assert_set_feature(qts, "host", "kvm-steal-time", false); > + assert_set_feature(qts, "host", "kvm-steal-time", true); > + } > + > if (kvm_supports_sve) { > g_assert(vls != 0); > max_vq = 64 - __builtin_clzll(vls); > @@ -577,6 +593,7 @@ static void test_query_cpu_model_expansion_kvm(const void *data) > assert_has_not_feature(qts, "host", "aarch64"); > assert_has_not_feature(qts, "host", "pmu"); > assert_has_not_feature(qts, "host", "sve"); > + assert_has_not_feature(qts, "host", "kvm-steal-time"); > } > > qtest_quit(qts); > This looks good to me Reviewed-by: Eric Auger <eric.auger@redhat.com> Thanks Eric
diff --git a/docs/system/arm/cpu-features.rst b/docs/system/arm/cpu-features.rst index 2d5c06cd016b..35196a6b759d 100644 --- a/docs/system/arm/cpu-features.rst +++ b/docs/system/arm/cpu-features.rst @@ -200,6 +200,17 @@ the list of KVM VCPU features and their descriptions. adjustment, also restoring the legacy (pre-5.0) behavior. + kvm-steal-time Since v5.2, kvm-steal-time is enabled by + default when KVM is enabled, the feature is + supported, and the guest is 64-bit. + + When kvm-steal-time is enabled a 64-bit guest + can account for time its CPUs were not running + due to the host not scheduling the corresponding + VCPU threads. The accounting statistics may + influence the guest scheduler behavior and/or be + exposed to the guest userspace. + SVE CPU Properties ================== diff --git a/hw/arm/virt.c b/hw/arm/virt.c index 6797eb397a7a..12efc2f095cb 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -151,6 +151,7 @@ static const MemMapEntry base_memmap[] = { [VIRT_PCDIMM_ACPI] = { 0x09070000, MEMORY_HOTPLUG_IO_LEN }, [VIRT_ACPI_GED] = { 0x09080000, ACPI_GED_EVT_SEL_LEN }, [VIRT_NVDIMM_ACPI] = { 0x09090000, NVDIMM_ACPI_IO_LEN}, + [VIRT_PVTIME] = { 0x090a0000, 0x00010000 }, [VIRT_MMIO] = { 0x0a000000, 0x00000200 }, /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */ [VIRT_PLATFORM_BUS] = { 0x0c000000, 0x02000000 }, @@ -1666,15 +1667,39 @@ static void finalize_gic_version(VirtMachineState *vms) * virt_cpu_post_init() must be called after the CPUs have * been realized and the GIC has been created. */ -static void virt_cpu_post_init(VirtMachineState *vms) +static void virt_cpu_post_init(VirtMachineState *vms, int max_cpus, + MemoryRegion *sysmem) { - bool aarch64, pmu; + bool aarch64, pmu, steal_time; CPUState *cpu; aarch64 = object_property_get_bool(OBJECT(first_cpu), "aarch64", NULL); pmu = object_property_get_bool(OBJECT(first_cpu), "pmu", NULL); + steal_time = object_property_get_bool(OBJECT(first_cpu), + "kvm-steal-time", NULL); if (kvm_enabled()) { + hwaddr pvtime_reg_base = vms->memmap[VIRT_PVTIME].base; + hwaddr pvtime_reg_size = vms->memmap[VIRT_PVTIME].size; + + if (steal_time) { + MemoryRegion *pvtime = g_new(MemoryRegion, 1); + hwaddr pvtime_size = max_cpus * PVTIME_SIZE_PER_CPU; + + /* The memory region size must be a multiple of host page size. */ + pvtime_size = REAL_HOST_PAGE_ALIGN(pvtime_size); + + if (pvtime_size > pvtime_reg_size) { + error_report("pvtime requires a %ld byte memory region for " + "%d CPUs, but only %ld has been reserved", + pvtime_size, max_cpus, pvtime_reg_size); + exit(1); + } + + memory_region_init_ram(pvtime, NULL, "pvtime", pvtime_size, NULL); + memory_region_add_subregion(sysmem, pvtime_reg_base, pvtime); + } + CPU_FOREACH(cpu) { if (pmu) { assert(arm_feature(&ARM_CPU(cpu)->env, ARM_FEATURE_PMU)); @@ -1683,6 +1708,10 @@ static void virt_cpu_post_init(VirtMachineState *vms) } kvm_arm_pmu_init(cpu); } + if (steal_time) { + kvm_arm_pvtime_init(cpu, pvtime_reg_base + + cpu->cpu_index * PVTIME_SIZE_PER_CPU); + } } } else { if (aarch64 && vms->highmem) { @@ -1853,6 +1882,11 @@ static void machvirt_init(MachineState *machine) object_property_set_bool(cpuobj, "kvm-no-adjvtime", true, NULL); } + if (vmc->no_kvm_steal_time && + object_property_find(cpuobj, "kvm-steal-time", NULL)) { + object_property_set_bool(cpuobj, "kvm-steal-time", false, NULL); + } + if (vmc->no_pmu && object_property_find(cpuobj, "pmu", NULL)) { object_property_set_bool(cpuobj, "pmu", false, NULL); } @@ -1924,7 +1958,7 @@ static void machvirt_init(MachineState *machine) create_gic(vms); - virt_cpu_post_init(vms); + virt_cpu_post_init(vms, possible_cpus->len, sysmem); fdt_add_pmu_nodes(vms); @@ -2566,8 +2600,11 @@ DEFINE_VIRT_MACHINE_AS_LATEST(5, 2) static void virt_machine_5_1_options(MachineClass *mc) { + VirtMachineClass *vmc = VIRT_MACHINE_CLASS(OBJECT_CLASS(mc)); + virt_machine_5_2_options(mc); compat_props_add(mc->compat_props, hw_compat_5_1, hw_compat_5_1_len); + vmc->no_kvm_steal_time = true; } DEFINE_VIRT_MACHINE(5, 1) diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h index dff67e1bef03..5fb43a009f7a 100644 --- a/include/hw/arm/virt.h +++ b/include/hw/arm/virt.h @@ -53,6 +53,9 @@ #define PPI(irq) ((irq) + 16) +/* See Linux kernel arch/arm64/include/asm/pvclock-abi.h */ +#define PVTIME_SIZE_PER_CPU 64 + enum { VIRT_FLASH, VIRT_MEM, @@ -80,6 +83,7 @@ enum { VIRT_PCDIMM_ACPI, VIRT_ACPI_GED, VIRT_NVDIMM_ACPI, + VIRT_PVTIME, VIRT_LOWMEMMAP_LAST, }; @@ -126,6 +130,7 @@ typedef struct { bool no_ged; /* Machines < 4.2 has no support for ACPI GED device */ bool kvm_no_adjvtime; bool acpi_expose_flash; + bool no_kvm_steal_time; } VirtMachineClass; typedef struct { diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 111579554fb9..866d0a9fb146 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -1308,6 +1308,16 @@ void arm_cpu_finalize_features(ARMCPU *cpu, Error **errp) return; } } + + if (kvm_enabled()) { +#ifdef TARGET_AARCH64 + kvm_arm_steal_time_finalize(cpu, &local_err); + if (local_err != NULL) { + error_propagate(errp, local_err); + return; + } +#endif + } } static void arm_cpu_realizefn(DeviceState *dev, Error **errp) diff --git a/target/arm/cpu.h b/target/arm/cpu.h index 9e8ed423ea1d..a4d4cb640c77 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -24,6 +24,7 @@ #include "hw/registerfields.h" #include "cpu-qom.h" #include "exec/cpu-defs.h" +#include "qapi/qapi-types-common.h" /* ARM processors have a weak memory model */ #define TCG_GUEST_DEFAULT_MO (0) @@ -859,6 +860,9 @@ struct ARMCPU { bool kvm_vtime_dirty; uint64_t kvm_vtime; + /* KVM steal time */ + OnOffAuto kvm_steal_time; + /* Uniprocessor system with MP extensions */ bool mp_is_up; diff --git a/target/arm/kvm.c b/target/arm/kvm.c index 8bb7318378b5..093a290453f6 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -192,6 +192,18 @@ static void kvm_no_adjvtime_set(Object *obj, bool value, Error **errp) ARM_CPU(obj)->kvm_adjvtime = !value; } +#ifdef TARGET_AARCH64 +static bool kvm_steal_time_get(Object *obj, Error **errp) +{ + return ARM_CPU(obj)->kvm_steal_time != ON_OFF_AUTO_OFF; +} + +static void kvm_steal_time_set(Object *obj, bool value, Error **errp) +{ + ARM_CPU(obj)->kvm_steal_time = value ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF; +} +#endif + /* KVM VCPU properties should be prefixed with "kvm-". */ void kvm_arm_add_vcpu_properties(Object *obj) { @@ -207,6 +219,14 @@ void kvm_arm_add_vcpu_properties(Object *obj) "the virtual counter. VM stopped time " "will be counted."); } + +#ifdef TARGET_AARCH64 + cpu->kvm_steal_time = ON_OFF_AUTO_AUTO; + object_property_add_bool(obj, "kvm-steal-time", kvm_steal_time_get, + kvm_steal_time_set); + object_property_set_description(obj, "kvm-steal-time", + "Set off to disable KVM steal time."); +#endif } bool kvm_arm_pmu_supported(void) diff --git a/target/arm/kvm32.c b/target/arm/kvm32.c index 0af46b41c847..d3f3195077fa 100644 --- a/target/arm/kvm32.c +++ b/target/arm/kvm32.c @@ -560,6 +560,11 @@ void kvm_arm_pmu_init(CPUState *cs) qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__); } +void kvm_arm_pvtime_init(CPUState *cs, uint64_t ipa) +{ + qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__); +} + #define ARM_REG_DFSR ARM_CP15_REG32(0, 5, 0, 0) #define ARM_REG_TTBCR ARM_CP15_REG32(0, 2, 0, 2) /* diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c index 116923790550..4de1eeb723ac 100644 --- a/target/arm/kvm64.c +++ b/target/arm/kvm64.c @@ -17,6 +17,7 @@ #include <linux/kvm.h> #include "qemu-common.h" +#include "qapi/error.h" #include "cpu.h" #include "qemu/timer.h" #include "qemu/error-report.h" @@ -398,19 +399,20 @@ static CPUWatchpoint *find_hw_watchpoint(CPUState *cpu, target_ulong addr) return NULL; } -static bool kvm_arm_pmu_set_attr(CPUState *cs, struct kvm_device_attr *attr) +static bool kvm_arm_set_device_attr(CPUState *cs, struct kvm_device_attr *attr, + const char *name) { int err; err = kvm_vcpu_ioctl(cs, KVM_HAS_DEVICE_ATTR, attr); if (err != 0) { - error_report("PMU: KVM_HAS_DEVICE_ATTR: %s", strerror(-err)); + error_report("%s: KVM_HAS_DEVICE_ATTR: %s", name, strerror(-err)); return false; } err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, attr); if (err != 0) { - error_report("PMU: KVM_SET_DEVICE_ATTR: %s", strerror(-err)); + error_report("%s: KVM_SET_DEVICE_ATTR: %s", name, strerror(-err)); return false; } @@ -427,7 +429,7 @@ void kvm_arm_pmu_init(CPUState *cs) if (!ARM_CPU(cs)->has_pmu) { return; } - if (!kvm_arm_pmu_set_attr(cs, &attr)) { + if (!kvm_arm_set_device_attr(cs, &attr, "PMU")) { error_report("failed to init PMU"); abort(); } @@ -444,12 +446,29 @@ void kvm_arm_pmu_set_irq(CPUState *cs, int irq) if (!ARM_CPU(cs)->has_pmu) { return; } - if (!kvm_arm_pmu_set_attr(cs, &attr)) { + if (!kvm_arm_set_device_attr(cs, &attr, "PMU")) { error_report("failed to set irq for PMU"); abort(); } } +void kvm_arm_pvtime_init(CPUState *cs, uint64_t ipa) +{ + struct kvm_device_attr attr = { + .group = KVM_ARM_VCPU_PVTIME_CTRL, + .attr = KVM_ARM_VCPU_PVTIME_IPA, + .addr = (uint64_t)&ipa, + }; + + if (ARM_CPU(cs)->kvm_steal_time == ON_OFF_AUTO_OFF) { + return; + } + if (!kvm_arm_set_device_attr(cs, &attr, "PVTIME IPA")) { + error_report("failed to init PVTIME IPA"); + abort(); + } +} + static int read_sys_reg32(int fd, uint32_t *pret, uint64_t id) { uint64_t ret; @@ -652,6 +671,54 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf) return true; } +void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp) +{ + static bool has_steal_time; + static bool probed; + int fdarray[3]; + + if (!probed) { + probed = true; + if (kvm_check_extension(kvm_state, KVM_CAP_VCPU_ATTRIBUTES)) { + if (!kvm_arm_create_scratch_host_vcpu(NULL, fdarray, NULL)) { + error_report("Failed to create scratch VCPU"); + abort(); + } + + has_steal_time = kvm_device_check_attr(fdarray[2], + KVM_ARM_VCPU_PVTIME_CTRL, + KVM_ARM_VCPU_PVTIME_IPA); + + kvm_arm_destroy_scratch_host_vcpu(fdarray); + } + } + + if (cpu->kvm_steal_time == ON_OFF_AUTO_AUTO) { + if (!has_steal_time || !arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) { + cpu->kvm_steal_time = ON_OFF_AUTO_OFF; + } else { + cpu->kvm_steal_time = ON_OFF_AUTO_ON; + } + } else if (cpu->kvm_steal_time == ON_OFF_AUTO_ON) { + if (!has_steal_time) { + error_setg(errp, "'kvm-steal-time' cannot be enabled " + "on this host"); + return; + } else if (!arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) { + /* + * DEN0057A chapter 2 says "This specification only covers + * systems in which the Execution state of the hypervisor + * as well as EL1 of virtual machines is AArch64.". And, + * to ensure that, the smc/hvc calls are only specified as + * smc64/hvc64. + */ + error_setg(errp, "'kvm-steal-time' cannot be enabled " + "for AArch32 guests"); + return; + } + } +} + bool kvm_arm_aarch32_supported(void) { return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL1_32BIT); diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h index 0da00eb6b20c..4a8969505967 100644 --- a/target/arm/kvm_arm.h +++ b/target/arm/kvm_arm.h @@ -267,6 +267,16 @@ void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu); */ void kvm_arm_add_vcpu_properties(Object *obj); +/** + * kvm_arm_steal_time_finalize: + * @cpu: ARMCPU for which to finalize kvm-steal-time + * @errp: Pointer to Error* for error propagation + * + * Validate the kvm-steal-time property selection and set its default + * based on KVM support and guest configuration. + */ +void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp); + /** * kvm_arm_aarch32_supported: * @@ -340,6 +350,16 @@ int kvm_arm_vgic_probe(void); void kvm_arm_pmu_set_irq(CPUState *cs, int irq); void kvm_arm_pmu_init(CPUState *cs); + +/** + * kvm_arm_pvtime_init: + * @cs: CPUState + * @ipa: Per-vcpu guest physical base address of the pvtime structures + * + * Initializes PVTIME for the VCPU, setting the PVTIME IPA to @ipa. + */ +void kvm_arm_pvtime_init(CPUState *cs, uint64_t ipa); + int kvm_arm_set_irq(int cpu, int irqtype, int irq, int level); #else @@ -393,6 +413,16 @@ static inline void kvm_arm_pmu_init(CPUState *cs) g_assert_not_reached(); } +static inline void kvm_arm_pvtime_init(CPUState *cs, uint64_t ipa) +{ + g_assert_not_reached(); +} + +static inline void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp) +{ + g_assert_not_reached(); +} + static inline void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map) { g_assert_not_reached(); diff --git a/target/arm/monitor.c b/target/arm/monitor.c index ba6e01abd037..bd3590604a71 100644 --- a/target/arm/monitor.c +++ b/target/arm/monitor.c @@ -103,7 +103,7 @@ static const char *cpu_model_advertised_features[] = { "sve128", "sve256", "sve384", "sve512", "sve640", "sve768", "sve896", "sve1024", "sve1152", "sve1280", "sve1408", "sve1536", "sve1664", "sve1792", "sve1920", "sve2048", - "kvm-no-adjvtime", + "kvm-no-adjvtime", "kvm-steal-time", NULL }; diff --git a/tests/qtest/arm-cpu-features.c b/tests/qtest/arm-cpu-features.c index f7e062c1891e..91b181f38268 100644 --- a/tests/qtest/arm-cpu-features.c +++ b/tests/qtest/arm-cpu-features.c @@ -452,6 +452,7 @@ static void test_query_cpu_model_expansion(const void *data) assert_set_feature(qts, "max", "pmu", true); assert_has_not_feature(qts, "max", "kvm-no-adjvtime"); + assert_has_not_feature(qts, "max", "kvm-steal-time"); if (g_str_equal(qtest_get_arch(), "aarch64")) { assert_has_feature_enabled(qts, "max", "aarch64"); @@ -493,6 +494,7 @@ static void test_query_cpu_model_expansion_kvm(const void *data) assert_set_feature(qts, "host", "kvm-no-adjvtime", false); if (g_str_equal(qtest_get_arch(), "aarch64")) { + bool kvm_supports_steal_time; bool kvm_supports_sve; char max_name[8], name[8]; uint32_t max_vq, vq; @@ -500,6 +502,10 @@ static void test_query_cpu_model_expansion_kvm(const void *data) QDict *resp; char *error; + assert_error(qts, "cortex-a15", + "We cannot guarantee the CPU type 'cortex-a15' works " + "with KVM on this host", NULL); + assert_has_feature_enabled(qts, "host", "aarch64"); /* Enabling and disabling pmu should always work. */ @@ -507,16 +513,26 @@ static void test_query_cpu_model_expansion_kvm(const void *data) assert_set_feature(qts, "host", "pmu", false); assert_set_feature(qts, "host", "pmu", true); - assert_error(qts, "cortex-a15", - "We cannot guarantee the CPU type 'cortex-a15' works " - "with KVM on this host", NULL); - + /* + * Some features would be enabled by default, but they're disabled + * because this instance of KVM doesn't support them. Test that the + * features are present, and, when enabled, issue further tests. + */ + assert_has_feature(qts, "host", "kvm-steal-time"); assert_has_feature(qts, "host", "sve"); + resp = do_query_no_props(qts, "host"); + kvm_supports_steal_time = resp_get_feature(resp, "kvm-steal-time"); kvm_supports_sve = resp_get_feature(resp, "sve"); vls = resp_get_sve_vls(resp); qobject_unref(resp); + if (kvm_supports_steal_time) { + /* If we have steal-time then we should be able to toggle it. */ + assert_set_feature(qts, "host", "kvm-steal-time", false); + assert_set_feature(qts, "host", "kvm-steal-time", true); + } + if (kvm_supports_sve) { g_assert(vls != 0); max_vq = 64 - __builtin_clzll(vls); @@ -577,6 +593,7 @@ static void test_query_cpu_model_expansion_kvm(const void *data) assert_has_not_feature(qts, "host", "aarch64"); assert_has_not_feature(qts, "host", "pmu"); assert_has_not_feature(qts, "host", "sve"); + assert_has_not_feature(qts, "host", "kvm-steal-time"); } qtest_quit(qts);
We add the kvm-steal-time CPU property and implement it for machvirt. A tiny bit of refactoring was also done to allow pmu and pvtime to use the same vcpu device helper functions. Signed-off-by: Andrew Jones <drjones@redhat.com> --- docs/system/arm/cpu-features.rst | 11 +++++ hw/arm/virt.c | 43 ++++++++++++++++-- include/hw/arm/virt.h | 5 +++ target/arm/cpu.c | 10 +++++ target/arm/cpu.h | 4 ++ target/arm/kvm.c | 20 +++++++++ target/arm/kvm32.c | 5 +++ target/arm/kvm64.c | 77 +++++++++++++++++++++++++++++--- target/arm/kvm_arm.h | 30 +++++++++++++ target/arm/monitor.c | 2 +- tests/qtest/arm-cpu-features.c | 25 +++++++++-- 11 files changed, 219 insertions(+), 13 deletions(-)