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Merge branch 'kvm-arm64/pmu-5.9' into kvmarm-master/next

Browse Source 
Signed-off-by: Marc Zyngier <maz@kernel.org>
This commit is contained in:
Marc Zyngier 2020-09-29 15:12:54 +01:00
commit 2e02cbb236
7 changed files with 257 additions and 30 deletions
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57
Documentation/virt/kvm/devices/vcpu.rst
View File

@ -25,8 +25,10 @@ Returns:
======= ========================================================
-EBUSY The PMU overflow interrupt is already set
-ENXIO The overflow interrupt not set when attempting to get it
-ENODEV PMUv3 not supported
-EFAULT Error reading interrupt number
-ENXIO PMUv3 not supported or the overflow interrupt not set
when attempting to get it
-ENODEV KVM_ARM_VCPU_PMU_V3 feature missing from VCPU
-EINVAL Invalid PMU overflow interrupt number supplied or
trying to set the IRQ number without using an in-kernel
irqchip.
@ -45,9 +47,10 @@ all vcpus, while as an SPI it must be a separate number per vcpu.
Returns:
======= ======================================================
-EEXIST Interrupt number already used
-ENODEV PMUv3 not supported or GIC not initialized
-ENXIO PMUv3 not properly configured or in-kernel irqchip not
configured as required prior to calling this attribute
-ENXIO PMUv3 not supported, missing VCPU feature or interrupt
number not set
-EBUSY PMUv3 already initialized
======= ======================================================
@ -55,6 +58,52 @@ Request the initialization of the PMUv3. If using the PMUv3 with an in-kernel
virtual GIC implementation, this must be done after initializing the in-kernel
irqchip.
1.3 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_FILTER
-----------------------------------------
:Parameters: in kvm_device_attr.addr the address for a PMU event filter is a
pointer to a struct kvm_pmu_event_filter
:Returns:
======= ======================================================
-ENODEV: PMUv3 not supported or GIC not initialized
-ENXIO: PMUv3 not properly configured or in-kernel irqchip not
configured as required prior to calling this attribute
-EBUSY: PMUv3 already initialized
-EINVAL: Invalid filter range
======= ======================================================
Request the installation of a PMU event filter described as follows:
struct kvm_pmu_event_filter {
__u16 base_event;
__u16 nevents;
#define KVM_PMU_EVENT_ALLOW 0
#define KVM_PMU_EVENT_DENY 1
__u8 action;
__u8 pad[3];
};
A filter range is defined as the range [@base_event, @base_event + @nevents),
together with an @action (KVM_PMU_EVENT_ALLOW or KVM_PMU_EVENT_DENY). The
first registered range defines the global policy (global ALLOW if the first
@action is DENY, global DENY if the first @action is ALLOW). Multiple ranges
can be programmed, and must fit within the event space defined by the PMU
architecture (10 bits on ARMv8.0, 16 bits from ARMv8.1 onwards).
Note: "Cancelling" a filter by registering the opposite action for the same
range doesn't change the default action. For example, installing an ALLOW
filter for event range [0:10) as the first filter and then applying a DENY
action for the same range will leave the whole range as disabled.
Restrictions: Event 0 (SW_INCR) is never filtered, as it doesn't count a
hardware event. Filtering event 0x1E (CHAIN) has no effect either, as it
isn't strictly speaking an event. Filtering the cycle counter is possible
using event 0x11 (CPU_CYCLES).
2. GROUP: KVM_ARM_VCPU_TIMER_CTRL
=================================

7
arch/arm64/include/asm/kvm_host.h
View File

@ -111,6 +111,13 @@ struct kvm_arch {
* supported.
*/
bool return_nisv_io_abort_to_user;
/*
* VM-wide PMU filter, implemented as a bitmap and big enough for
* up to 2^10 events (ARMv8.0) or 2^16 events (ARMv8.1+).
*/
unsigned long *pmu_filter;
unsigned int pmuver;
};
struct kvm_vcpu_fault_info {

16
arch/arm64/include/uapi/asm/kvm.h
View File

@ -159,6 +159,21 @@ struct kvm_sync_regs {
struct kvm_arch_memory_slot {
};
/*
* PMU filter structure. Describe a range of events with a particular
* action. To be used with KVM_ARM_VCPU_PMU_V3_FILTER.
*/
struct kvm_pmu_event_filter {
__u16 base_event;
__u16 nevents;
#define KVM_PMU_EVENT_ALLOW 0
#define KVM_PMU_EVENT_DENY 1
__u8 action;
__u8 pad[3];
};
/* for KVM_GET/SET_VCPU_EVENTS */
struct kvm_vcpu_events {
struct {
@ -329,6 +344,7 @@ struct kvm_vcpu_events {
#define KVM_ARM_VCPU_PMU_V3_CTRL 0
#define KVM_ARM_VCPU_PMU_V3_IRQ 0
#define KVM_ARM_VCPU_PMU_V3_INIT 1
#define KVM_ARM_VCPU_PMU_V3_FILTER 2
#define KVM_ARM_VCPU_TIMER_CTRL 1
#define KVM_ARM_VCPU_TIMER_IRQ_VTIMER 0
#define KVM_ARM_VCPU_TIMER_IRQ_PTIMER 1

2
arch/arm64/kvm/arm.c
View File

@ -147,6 +147,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
{
int i;
bitmap_free(kvm->arch.pmu_filter);
kvm_vgic_destroy(kvm);
for (i = 0; i < KVM_MAX_VCPUS; ++i) {

195
arch/arm64/kvm/pmu-emul.c
View File

@ -20,6 +20,21 @@ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc);
#define PERF_ATTR_CFG1_KVM_PMU_CHAINED 0x1
static u32 kvm_pmu_event_mask(struct kvm *kvm)
{
switch (kvm->arch.pmuver) {
case 1: /* ARMv8.0 */
return GENMASK(9, 0);
case 4: /* ARMv8.1 */
case 5: /* ARMv8.4 */
case 6: /* ARMv8.5 */
return GENMASK(15, 0);
default: /* Shouldn't be here, just for sanity */
WARN_ONCE(1, "Unknown PMU version %d\n", kvm->arch.pmuver);
return 0;
}
}
/**
* kvm_pmu_idx_is_64bit - determine if select_idx is a 64bit counter
* @vcpu: The vcpu pointer
@ -100,7 +115,7 @@ static bool kvm_pmu_idx_has_chain_evtype(struct kvm_vcpu *vcpu, u64 select_idx)
return false;
reg = PMEVTYPER0_EL0 + select_idx;
eventsel = __vcpu_sys_reg(vcpu, reg) & ARMV8_PMU_EVTYPE_EVENT;
eventsel = __vcpu_sys_reg(vcpu, reg) & kvm_pmu_event_mask(vcpu->kvm);
return eventsel == ARMV8_PMUV3_PERFCTR_CHAIN;
}
@ -495,7 +510,7 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val)
/* PMSWINC only applies to ... SW_INC! */
type = __vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + i);
type &= ARMV8_PMU_EVTYPE_EVENT;
type &= kvm_pmu_event_mask(vcpu->kvm);
if (type != ARMV8_PMUV3_PERFCTR_SW_INCR)
continue;
@ -578,11 +593,21 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx)
data = __vcpu_sys_reg(vcpu, reg);
kvm_pmu_stop_counter(vcpu, pmc);
eventsel = data & ARMV8_PMU_EVTYPE_EVENT;
if (pmc->idx == ARMV8_PMU_CYCLE_IDX)
eventsel = ARMV8_PMUV3_PERFCTR_CPU_CYCLES;
else
eventsel = data & kvm_pmu_event_mask(vcpu->kvm);
/* Software increment event does't need to be backed by a perf event */
if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR &&
pmc->idx != ARMV8_PMU_CYCLE_IDX)
/* Software increment event doesn't need to be backed by a perf event */
if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR)
return;
/*
* If we have a filter in place and that the event isn't allowed, do
* not install a perf event either.
*/
if (vcpu->kvm->arch.pmu_filter &&
!test_bit(eventsel, vcpu->kvm->arch.pmu_filter))
return;
memset(&attr, 0, sizeof(struct perf_event_attr));
@ -594,8 +619,7 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx)
attr.exclude_kernel = data & ARMV8_PMU_EXCLUDE_EL1 ? 1 : 0;
attr.exclude_hv = 1; /* Don't count EL2 events */
attr.exclude_host = 1; /* Don't count host events */
attr.config = (pmc->idx == ARMV8_PMU_CYCLE_IDX) ?
ARMV8_PMUV3_PERFCTR_CPU_CYCLES : eventsel;
attr.config = eventsel;
counter = kvm_pmu_get_pair_counter_value(vcpu, pmc);
@ -679,17 +703,95 @@ static void kvm_pmu_update_pmc_chained(struct kvm_vcpu *vcpu, u64 select_idx)
void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
u64 select_idx)
{
u64 reg, event_type = data & ARMV8_PMU_EVTYPE_MASK;
u64 reg, mask;
mask = ARMV8_PMU_EVTYPE_MASK;
mask &= ~ARMV8_PMU_EVTYPE_EVENT;
mask |= kvm_pmu_event_mask(vcpu->kvm);
reg = (select_idx == ARMV8_PMU_CYCLE_IDX)
? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + select_idx;
__vcpu_sys_reg(vcpu, reg) = event_type;
__vcpu_sys_reg(vcpu, reg) = data & mask;
kvm_pmu_update_pmc_chained(vcpu, select_idx);
kvm_pmu_create_perf_event(vcpu, select_idx);
}
static int kvm_pmu_probe_pmuver(void)
{
struct perf_event_attr attr = { };
struct perf_event *event;
struct arm_pmu *pmu;
int pmuver = 0xf;
/*
* Create a dummy event that only counts user cycles. As we'll never
* leave this function with the event being live, it will never
* count anything. But it allows us to probe some of the PMU
* details. Yes, this is terrible.
*/
attr.type = PERF_TYPE_RAW;
attr.size = sizeof(attr);
attr.pinned = 1;
attr.disabled = 0;
attr.exclude_user = 0;
attr.exclude_kernel = 1;
attr.exclude_hv = 1;
attr.exclude_host = 1;
attr.config = ARMV8_PMUV3_PERFCTR_CPU_CYCLES;
attr.sample_period = GENMASK(63, 0);
event = perf_event_create_kernel_counter(&attr, -1, current,
kvm_pmu_perf_overflow, &attr);
if (IS_ERR(event)) {
pr_err_once("kvm: pmu event creation failed %ld\n",
PTR_ERR(event));
return 0xf;
}
if (event->pmu) {
pmu = to_arm_pmu(event->pmu);
if (pmu->pmuver)
pmuver = pmu->pmuver;
}
perf_event_disable(event);
perf_event_release_kernel(event);
return pmuver;
}
u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1)
{
unsigned long *bmap = vcpu->kvm->arch.pmu_filter;
u64 val, mask = 0;
int base, i;
if (!pmceid1) {
val = read_sysreg(pmceid0_el0);
base = 0;
} else {
val = read_sysreg(pmceid1_el0);
base = 32;
}
if (!bmap)
return val;
for (i = 0; i < 32; i += 8) {
u64 byte;
byte = bitmap_get_value8(bmap, base + i);
mask |= byte << i;
byte = bitmap_get_value8(bmap, 0x4000 + base + i);
mask |= byte << (32 + i);
}
return val & mask;
}
bool kvm_arm_support_pmu_v3(void)
{
/*
@ -735,15 +837,6 @@ int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu)
static int kvm_arm_pmu_v3_init(struct kvm_vcpu *vcpu)
{
if (!kvm_arm_support_pmu_v3())
return -ENODEV;
if (!test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features))
return -ENXIO;
if (vcpu->arch.pmu.created)
return -EBUSY;
if (irqchip_in_kernel(vcpu->kvm)) {
int ret;
@ -796,6 +889,19 @@ static bool pmu_irq_is_valid(struct kvm *kvm, int irq)
int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
{
if (!kvm_arm_support_pmu_v3() ||
!test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features))
return -ENODEV;
if (vcpu->arch.pmu.created)
return -EBUSY;
if (!vcpu->kvm->arch.pmuver)
vcpu->kvm->arch.pmuver = kvm_pmu_probe_pmuver();
if (vcpu->kvm->arch.pmuver == 0xf)
return -ENODEV;
switch (attr->attr) {
case KVM_ARM_VCPU_PMU_V3_IRQ: {
int __user *uaddr = (int __user *)(long)attr->addr;
@ -804,9 +910,6 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
if (!irqchip_in_kernel(vcpu->kvm))
return -EINVAL;
if (!test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features))
return -ENODEV;
if (get_user(irq, uaddr))
return -EFAULT;
@ -824,6 +927,53 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
vcpu->arch.pmu.irq_num = irq;
return 0;
}
case KVM_ARM_VCPU_PMU_V3_FILTER: {
struct kvm_pmu_event_filter __user *uaddr;
struct kvm_pmu_event_filter filter;
int nr_events;
nr_events = kvm_pmu_event_mask(vcpu->kvm) + 1;
uaddr = (struct kvm_pmu_event_filter __user *)(long)attr->addr;
if (copy_from_user(&filter, uaddr, sizeof(filter)))
return -EFAULT;
if (((u32)filter.base_event + filter.nevents) > nr_events ||
(filter.action != KVM_PMU_EVENT_ALLOW &&
filter.action != KVM_PMU_EVENT_DENY))
return -EINVAL;
mutex_lock(&vcpu->kvm->lock);
if (!vcpu->kvm->arch.pmu_filter) {
vcpu->kvm->arch.pmu_filter = bitmap_alloc(nr_events, GFP_KERNEL);
if (!vcpu->kvm->arch.pmu_filter) {
mutex_unlock(&vcpu->kvm->lock);
return -ENOMEM;
}
/*
* The default depends on the first applied filter.
* If it allows events, the default is to deny.
* Conversely, if the first filter denies a set of
* events, the default is to allow.
*/
if (filter.action == KVM_PMU_EVENT_ALLOW)
bitmap_zero(vcpu->kvm->arch.pmu_filter, nr_events);
else
bitmap_fill(vcpu->kvm->arch.pmu_filter, nr_events);
}
if (filter.action == KVM_PMU_EVENT_ALLOW)
bitmap_set(vcpu->kvm->arch.pmu_filter, filter.base_event, filter.nevents);
else
bitmap_clear(vcpu->kvm->arch.pmu_filter, filter.base_event, filter.nevents);
mutex_unlock(&vcpu->kvm->lock);
return 0;
}
case KVM_ARM_VCPU_PMU_V3_INIT:
return kvm_arm_pmu_v3_init(vcpu);
}
@ -860,6 +1010,7 @@ int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
switch (attr->attr) {
case KVM_ARM_VCPU_PMU_V3_IRQ:
case KVM_ARM_VCPU_PMU_V3_INIT:
case KVM_ARM_VCPU_PMU_V3_FILTER:
if (kvm_arm_support_pmu_v3() &&
test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features))
return 0;

5
arch/arm64/kvm/sys_regs.c
View File

@ -769,10 +769,7 @@ static bool access_pmceid(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
if (pmu_access_el0_disabled(vcpu))
return false;
if (!(p->Op2 & 1))
pmceid = read_sysreg(pmceid0_el0);
else
pmceid = read_sysreg(pmceid1_el0);
pmceid = kvm_pmu_get_pmceid(vcpu, (p->Op2 & 1));
p->regval = pmceid;

5
include/kvm/arm_pmu.h
View File

@ -34,6 +34,7 @@ struct kvm_pmu {
u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx);
void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val);
u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu);
u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1);
void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu);
void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu);
void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu);
@ -108,6 +109,10 @@ static inline int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu)
{
return 0;
}
static inline u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1)
{
return 0;
}
#endif
#endif