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linux-sg2042/arch/arm64/kvm/pmu.c

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arm64: KVM: Add accessors to track guest/host only counters In order to effeciently switch events_{guest,host} perf counters at guest entry/exit we add bitfields to kvm_cpu_context for guest and host events as well as accessors for updating them. A function is also provided which allows the PMU driver to determine if a counter should start counting when it is enabled. With exclude_host, we may only start counting when entering the guest. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:12 +08:00
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2019 Arm Limited
* Author: Andrew Murray <Andrew.Murray@arm.com>
*/
#include <linux/kvm_host.h>
#include <linux/perf_event.h>
arm64: KVM: Enable !VHE support for :G/:H perf event modifiers Enable/disable event counters as appropriate when entering and exiting the guest to enable support for guest or host only event counting. For both VHE and non-VHE we switch the counters between host/guest at EL2. The PMU may be on when we change which counters are enabled however we avoid adding an isb as we instead rely on existing context synchronisation events: the eret to enter the guest (__guest_enter) and eret in kvm_call_hyp for __kvm_vcpu_run_nvhe on returning. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:14 +08:00
#include <asm/kvm_hyp.h>
arm64: KVM: Add accessors to track guest/host only counters In order to effeciently switch events_{guest,host} perf counters at guest entry/exit we add bitfields to kvm_cpu_context for guest and host events as well as accessors for updating them. A function is also provided which allows the PMU driver to determine if a counter should start counting when it is enabled. With exclude_host, we may only start counting when entering the guest. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:12 +08:00
/*
arm64: KVM: Enable VHE support for :G/:H perf event modifiers With VHE different exception levels are used between the host (EL2) and guest (EL1) with a shared exception level for userpace (EL0). We can take advantage of this and use the PMU's exception level filtering to avoid enabling/disabling counters in the world-switch code. Instead we just modify the counter type to include or exclude EL0 at vcpu_{load,put} time. We also ensure that trapped PMU system register writes do not re-enable EL0 when reconfiguring the backing perf events. This approach completely avoids blackout windows seen with !VHE. Suggested-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:15 +08:00
* Given the perf event attributes and system type, determine
* if we are going to need to switch counters at guest entry/exit.
arm64: KVM: Add accessors to track guest/host only counters In order to effeciently switch events_{guest,host} perf counters at guest entry/exit we add bitfields to kvm_cpu_context for guest and host events as well as accessors for updating them. A function is also provided which allows the PMU driver to determine if a counter should start counting when it is enabled. With exclude_host, we may only start counting when entering the guest. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:12 +08:00
*/
static bool kvm_pmu_switch_needed(struct perf_event_attr *attr)
{
arm64: KVM: Enable VHE support for :G/:H perf event modifiers With VHE different exception levels are used between the host (EL2) and guest (EL1) with a shared exception level for userpace (EL0). We can take advantage of this and use the PMU's exception level filtering to avoid enabling/disabling counters in the world-switch code. Instead we just modify the counter type to include or exclude EL0 at vcpu_{load,put} time. We also ensure that trapped PMU system register writes do not re-enable EL0 when reconfiguring the backing perf events. This approach completely avoids blackout windows seen with !VHE. Suggested-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:15 +08:00
/**
* With VHE the guest kernel runs at EL1 and the host at EL2,
* where user (EL0) is excluded then we have no reason to switch
* counters.
*/
if (has_vhe() && attr->exclude_user)
return false;
arm64: KVM: Add accessors to track guest/host only counters In order to effeciently switch events_{guest,host} perf counters at guest entry/exit we add bitfields to kvm_cpu_context for guest and host events as well as accessors for updating them. A function is also provided which allows the PMU driver to determine if a counter should start counting when it is enabled. With exclude_host, we may only start counting when entering the guest. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:12 +08:00
/* Only switch if attributes are different */
return (attr->exclude_host != attr->exclude_guest);
}
/*
* Add events to track that we may want to switch at guest entry/exit
* time.
*/
void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr)
{
struct kvm_host_data *ctx = this_cpu_ptr(&kvm_host_data);
if (!kvm_pmu_switch_needed(attr))
return;
if (!attr->exclude_host)
ctx->pmu_events.events_host |= set;
if (!attr->exclude_guest)
ctx->pmu_events.events_guest |= set;
}
/*
* Stop tracking events
*/
void kvm_clr_pmu_events(u32 clr)
{
struct kvm_host_data *ctx = this_cpu_ptr(&kvm_host_data);
ctx->pmu_events.events_host &= ~clr;
ctx->pmu_events.events_guest &= ~clr;
}
arm64: KVM: Enable !VHE support for :G/:H perf event modifiers Enable/disable event counters as appropriate when entering and exiting the guest to enable support for guest or host only event counting. For both VHE and non-VHE we switch the counters between host/guest at EL2. The PMU may be on when we change which counters are enabled however we avoid adding an isb as we instead rely on existing context synchronisation events: the eret to enter the guest (__guest_enter) and eret in kvm_call_hyp for __kvm_vcpu_run_nvhe on returning. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:14 +08:00
arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg Upon entering or exiting a guest we may modify multiple PMU counters to enable of disable EL0 filtering. We presently do this via the indirect PMXEVTYPER_EL0 system register (where the counter we modify is selected by PMSELR). With this approach it is necessary to order the writes via isb instructions such that we select the correct counter before modifying it. Let's avoid potentially expensive instruction barriers by using the direct PMEVTYPER<n>_EL0 registers instead. As the change to counter type relates only to EL0 filtering we can rely on the implicit instruction barrier which occurs when we transition from EL2 to EL1 on entering the guest. On returning to userspace we can, at the latest, rely on the implicit barrier between EL2 and EL0. We can also depend on the explicit isb in armv8pmu_select_counter to order our write against any other kernel changes by the PMU driver to the type register as a result of preemption. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:16 +08:00
#define PMEVTYPER_READ_CASE(idx) \
case idx: \
return read_sysreg(pmevtyper##idx##_el0)
#define PMEVTYPER_WRITE_CASE(idx) \
case idx: \
write_sysreg(val, pmevtyper##idx##_el0); \
break
#define PMEVTYPER_CASES(readwrite) \
PMEVTYPER_##readwrite##_CASE(0); \
PMEVTYPER_##readwrite##_CASE(1); \
PMEVTYPER_##readwrite##_CASE(2); \
PMEVTYPER_##readwrite##_CASE(3); \
PMEVTYPER_##readwrite##_CASE(4); \
PMEVTYPER_##readwrite##_CASE(5); \
PMEVTYPER_##readwrite##_CASE(6); \
PMEVTYPER_##readwrite##_CASE(7); \
PMEVTYPER_##readwrite##_CASE(8); \
PMEVTYPER_##readwrite##_CASE(9); \
PMEVTYPER_##readwrite##_CASE(10); \
PMEVTYPER_##readwrite##_CASE(11); \
PMEVTYPER_##readwrite##_CASE(12); \
PMEVTYPER_##readwrite##_CASE(13); \
PMEVTYPER_##readwrite##_CASE(14); \
PMEVTYPER_##readwrite##_CASE(15); \
PMEVTYPER_##readwrite##_CASE(16); \
PMEVTYPER_##readwrite##_CASE(17); \
PMEVTYPER_##readwrite##_CASE(18); \
PMEVTYPER_##readwrite##_CASE(19); \
PMEVTYPER_##readwrite##_CASE(20); \
PMEVTYPER_##readwrite##_CASE(21); \
PMEVTYPER_##readwrite##_CASE(22); \
PMEVTYPER_##readwrite##_CASE(23); \
PMEVTYPER_##readwrite##_CASE(24); \
PMEVTYPER_##readwrite##_CASE(25); \
PMEVTYPER_##readwrite##_CASE(26); \
PMEVTYPER_##readwrite##_CASE(27); \
PMEVTYPER_##readwrite##_CASE(28); \
PMEVTYPER_##readwrite##_CASE(29); \
PMEVTYPER_##readwrite##_CASE(30)
/*
arm64: KVM: Fix perf cycle counter support for VHE The kvm_vcpu_pmu_{read,write}_evtype_direct functions do not handle the cycle counter use-case, this leads to inaccurate counts and a WARN message when using perf with the cycle counter (-e cycle). Let's fix this by adding a use case for pmccfiltr_el0. Fixes: 39e3406a090a ("arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg") Reported-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-30 03:13:05 +08:00
* Read a value direct from PMEVTYPER<idx> where idx is 0-30
* or PMCCFILTR_EL0 where idx is ARMV8_PMU_CYCLE_IDX (31).
arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg Upon entering or exiting a guest we may modify multiple PMU counters to enable of disable EL0 filtering. We presently do this via the indirect PMXEVTYPER_EL0 system register (where the counter we modify is selected by PMSELR). With this approach it is necessary to order the writes via isb instructions such that we select the correct counter before modifying it. Let's avoid potentially expensive instruction barriers by using the direct PMEVTYPER<n>_EL0 registers instead. As the change to counter type relates only to EL0 filtering we can rely on the implicit instruction barrier which occurs when we transition from EL2 to EL1 on entering the guest. On returning to userspace we can, at the latest, rely on the implicit barrier between EL2 and EL0. We can also depend on the explicit isb in armv8pmu_select_counter to order our write against any other kernel changes by the PMU driver to the type register as a result of preemption. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:16 +08:00
*/
static u64 kvm_vcpu_pmu_read_evtype_direct(int idx)
{
switch (idx) {
PMEVTYPER_CASES(READ);
arm64: KVM: Fix perf cycle counter support for VHE The kvm_vcpu_pmu_{read,write}_evtype_direct functions do not handle the cycle counter use-case, this leads to inaccurate counts and a WARN message when using perf with the cycle counter (-e cycle). Let's fix this by adding a use case for pmccfiltr_el0. Fixes: 39e3406a090a ("arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg") Reported-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-30 03:13:05 +08:00
case ARMV8_PMU_CYCLE_IDX:
return read_sysreg(pmccfiltr_el0);
arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg Upon entering or exiting a guest we may modify multiple PMU counters to enable of disable EL0 filtering. We presently do this via the indirect PMXEVTYPER_EL0 system register (where the counter we modify is selected by PMSELR). With this approach it is necessary to order the writes via isb instructions such that we select the correct counter before modifying it. Let's avoid potentially expensive instruction barriers by using the direct PMEVTYPER<n>_EL0 registers instead. As the change to counter type relates only to EL0 filtering we can rely on the implicit instruction barrier which occurs when we transition from EL2 to EL1 on entering the guest. On returning to userspace we can, at the latest, rely on the implicit barrier between EL2 and EL0. We can also depend on the explicit isb in armv8pmu_select_counter to order our write against any other kernel changes by the PMU driver to the type register as a result of preemption. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:16 +08:00
default:
WARN_ON(1);
}
return 0;
}
/*
arm64: KVM: Fix perf cycle counter support for VHE The kvm_vcpu_pmu_{read,write}_evtype_direct functions do not handle the cycle counter use-case, this leads to inaccurate counts and a WARN message when using perf with the cycle counter (-e cycle). Let's fix this by adding a use case for pmccfiltr_el0. Fixes: 39e3406a090a ("arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg") Reported-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-30 03:13:05 +08:00
* Write a value direct to PMEVTYPER<idx> where idx is 0-30
* or PMCCFILTR_EL0 where idx is ARMV8_PMU_CYCLE_IDX (31).
arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg Upon entering or exiting a guest we may modify multiple PMU counters to enable of disable EL0 filtering. We presently do this via the indirect PMXEVTYPER_EL0 system register (where the counter we modify is selected by PMSELR). With this approach it is necessary to order the writes via isb instructions such that we select the correct counter before modifying it. Let's avoid potentially expensive instruction barriers by using the direct PMEVTYPER<n>_EL0 registers instead. As the change to counter type relates only to EL0 filtering we can rely on the implicit instruction barrier which occurs when we transition from EL2 to EL1 on entering the guest. On returning to userspace we can, at the latest, rely on the implicit barrier between EL2 and EL0. We can also depend on the explicit isb in armv8pmu_select_counter to order our write against any other kernel changes by the PMU driver to the type register as a result of preemption. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:16 +08:00
*/
static void kvm_vcpu_pmu_write_evtype_direct(int idx, u32 val)
{
switch (idx) {
PMEVTYPER_CASES(WRITE);
arm64: KVM: Fix perf cycle counter support for VHE The kvm_vcpu_pmu_{read,write}_evtype_direct functions do not handle the cycle counter use-case, this leads to inaccurate counts and a WARN message when using perf with the cycle counter (-e cycle). Let's fix this by adding a use case for pmccfiltr_el0. Fixes: 39e3406a090a ("arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg") Reported-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-30 03:13:05 +08:00
case ARMV8_PMU_CYCLE_IDX:
write_sysreg(val, pmccfiltr_el0);
break;
arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg Upon entering or exiting a guest we may modify multiple PMU counters to enable of disable EL0 filtering. We presently do this via the indirect PMXEVTYPER_EL0 system register (where the counter we modify is selected by PMSELR). With this approach it is necessary to order the writes via isb instructions such that we select the correct counter before modifying it. Let's avoid potentially expensive instruction barriers by using the direct PMEVTYPER<n>_EL0 registers instead. As the change to counter type relates only to EL0 filtering we can rely on the implicit instruction barrier which occurs when we transition from EL2 to EL1 on entering the guest. On returning to userspace we can, at the latest, rely on the implicit barrier between EL2 and EL0. We can also depend on the explicit isb in armv8pmu_select_counter to order our write against any other kernel changes by the PMU driver to the type register as a result of preemption. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:16 +08:00
default:
WARN_ON(1);
}
}
arm64: KVM: Enable VHE support for :G/:H perf event modifiers With VHE different exception levels are used between the host (EL2) and guest (EL1) with a shared exception level for userpace (EL0). We can take advantage of this and use the PMU's exception level filtering to avoid enabling/disabling counters in the world-switch code. Instead we just modify the counter type to include or exclude EL0 at vcpu_{load,put} time. We also ensure that trapped PMU system register writes do not re-enable EL0 when reconfiguring the backing perf events. This approach completely avoids blackout windows seen with !VHE. Suggested-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:15 +08:00
/*
* Modify ARMv8 PMU events to include EL0 counting
*/
static void kvm_vcpu_pmu_enable_el0(unsigned long events)
{
u64 typer;
u32 counter;
for_each_set_bit(counter, &events, 32) {
arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg Upon entering or exiting a guest we may modify multiple PMU counters to enable of disable EL0 filtering. We presently do this via the indirect PMXEVTYPER_EL0 system register (where the counter we modify is selected by PMSELR). With this approach it is necessary to order the writes via isb instructions such that we select the correct counter before modifying it. Let's avoid potentially expensive instruction barriers by using the direct PMEVTYPER<n>_EL0 registers instead. As the change to counter type relates only to EL0 filtering we can rely on the implicit instruction barrier which occurs when we transition from EL2 to EL1 on entering the guest. On returning to userspace we can, at the latest, rely on the implicit barrier between EL2 and EL0. We can also depend on the explicit isb in armv8pmu_select_counter to order our write against any other kernel changes by the PMU driver to the type register as a result of preemption. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:16 +08:00
typer = kvm_vcpu_pmu_read_evtype_direct(counter);
typer &= ~ARMV8_PMU_EXCLUDE_EL0;
kvm_vcpu_pmu_write_evtype_direct(counter, typer);
arm64: KVM: Enable VHE support for :G/:H perf event modifiers With VHE different exception levels are used between the host (EL2) and guest (EL1) with a shared exception level for userpace (EL0). We can take advantage of this and use the PMU's exception level filtering to avoid enabling/disabling counters in the world-switch code. Instead we just modify the counter type to include or exclude EL0 at vcpu_{load,put} time. We also ensure that trapped PMU system register writes do not re-enable EL0 when reconfiguring the backing perf events. This approach completely avoids blackout windows seen with !VHE. Suggested-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:15 +08:00
}
}
/*
* Modify ARMv8 PMU events to exclude EL0 counting
*/
static void kvm_vcpu_pmu_disable_el0(unsigned long events)
{
u64 typer;
u32 counter;
for_each_set_bit(counter, &events, 32) {
arm64: KVM: Avoid isb's by using direct pmxevtyper sysreg Upon entering or exiting a guest we may modify multiple PMU counters to enable of disable EL0 filtering. We presently do this via the indirect PMXEVTYPER_EL0 system register (where the counter we modify is selected by PMSELR). With this approach it is necessary to order the writes via isb instructions such that we select the correct counter before modifying it. Let's avoid potentially expensive instruction barriers by using the direct PMEVTYPER<n>_EL0 registers instead. As the change to counter type relates only to EL0 filtering we can rely on the implicit instruction barrier which occurs when we transition from EL2 to EL1 on entering the guest. On returning to userspace we can, at the latest, rely on the implicit barrier between EL2 and EL0. We can also depend on the explicit isb in armv8pmu_select_counter to order our write against any other kernel changes by the PMU driver to the type register as a result of preemption. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:16 +08:00
typer = kvm_vcpu_pmu_read_evtype_direct(counter);
typer |= ARMV8_PMU_EXCLUDE_EL0;
kvm_vcpu_pmu_write_evtype_direct(counter, typer);
arm64: KVM: Enable VHE support for :G/:H perf event modifiers With VHE different exception levels are used between the host (EL2) and guest (EL1) with a shared exception level for userpace (EL0). We can take advantage of this and use the PMU's exception level filtering to avoid enabling/disabling counters in the world-switch code. Instead we just modify the counter type to include or exclude EL0 at vcpu_{load,put} time. We also ensure that trapped PMU system register writes do not re-enable EL0 when reconfiguring the backing perf events. This approach completely avoids blackout windows seen with !VHE. Suggested-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-10 03:22:15 +08:00
}
}
/*
* On VHE ensure that only guest events have EL0 counting enabled
*/
void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *host_ctxt;
struct kvm_host_data *host;
u32 events_guest, events_host;
if (!has_vhe())
return;
host_ctxt = vcpu->arch.host_cpu_context;
host = container_of(host_ctxt, struct kvm_host_data, host_ctxt);
events_guest = host->pmu_events.events_guest;
events_host = host->pmu_events.events_host;
kvm_vcpu_pmu_enable_el0(events_guest);
kvm_vcpu_pmu_disable_el0(events_host);
}
/*
* On VHE ensure that only host events have EL0 counting enabled
*/
void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *host_ctxt;
struct kvm_host_data *host;
u32 events_guest, events_host;
if (!has_vhe())
return;
host_ctxt = vcpu->arch.host_cpu_context;
host = container_of(host_ctxt, struct kvm_host_data, host_ctxt);
events_guest = host->pmu_events.events_guest;
events_host = host->pmu_events.events_host;
kvm_vcpu_pmu_enable_el0(events_host);
kvm_vcpu_pmu_disable_el0(events_guest);
}