linux-stable/include/kvm/arm_pmu.h
Marc Zyngier e840f42a49 KVM: arm64: Fix PMU probe ordering
Russell reported that since 5.13, KVM's probing of the PMU has
started to fail on his HW. As it turns out, there is an implicit
ordering dependency between the architectural PMU probing code and
and KVM's own probing. If, due to probe ordering reasons, KVM probes
before the PMU driver, it will fail to detect the PMU and prevent it
from being advertised to guests as well as the VMM.

Obviously, this is one probing too many, and we should be able to
deal with any ordering.

Add a callback from the PMU code into KVM to advertise the registration
of a host CPU PMU, allowing for any probing order.

Fixes: 5421db1be3 ("KVM: arm64: Divorce the perf code from oprofile helpers")
Reported-by: "Russell King (Oracle)" <linux@armlinux.org.uk>
Tested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/YUYRKVflRtUytzy5@shell.armlinux.org.uk
Cc: stable@vger.kernel.org
2021-09-20 12:43:34 +01:00

122 lines
4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2015 Linaro Ltd.
* Author: Shannon Zhao <shannon.zhao@linaro.org>
*/
#ifndef __ASM_ARM_KVM_PMU_H
#define __ASM_ARM_KVM_PMU_H
#include <linux/perf_event.h>
#include <asm/perf_event.h>
#define ARMV8_PMU_CYCLE_IDX (ARMV8_PMU_MAX_COUNTERS - 1)
#define ARMV8_PMU_MAX_COUNTER_PAIRS ((ARMV8_PMU_MAX_COUNTERS + 1) >> 1)
DECLARE_STATIC_KEY_FALSE(kvm_arm_pmu_available);
static __always_inline bool kvm_arm_support_pmu_v3(void)
{
return static_branch_likely(&kvm_arm_pmu_available);
}
#ifdef CONFIG_HW_PERF_EVENTS
struct kvm_pmc {
u8 idx; /* index into the pmu->pmc array */
struct perf_event *perf_event;
};
struct kvm_pmu {
int irq_num;
struct kvm_pmc pmc[ARMV8_PMU_MAX_COUNTERS];
DECLARE_BITMAP(chained, ARMV8_PMU_MAX_COUNTER_PAIRS);
bool created;
bool irq_level;
struct irq_work overflow_work;
};
#define kvm_arm_pmu_irq_initialized(v) ((v)->arch.pmu.irq_num >= VGIC_NR_SGIS)
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);
void kvm_pmu_disable_counter_mask(struct kvm_vcpu *vcpu, u64 val);
void kvm_pmu_enable_counter_mask(struct kvm_vcpu *vcpu, u64 val);
void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu);
void kvm_pmu_sync_hwstate(struct kvm_vcpu *vcpu);
bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu);
void kvm_pmu_update_run(struct kvm_vcpu *vcpu);
void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val);
void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val);
void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data,
u64 select_idx);
int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_pmu_v3_get_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu);
#else
struct kvm_pmu {
};
#define kvm_arm_pmu_irq_initialized(v) (false)
static inline u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu,
u64 select_idx)
{
return 0;
}
static inline void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu,
u64 select_idx, u64 val) {}
static inline u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu)
{
return 0;
}
static inline void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_disable_counter_mask(struct kvm_vcpu *vcpu, u64 val) {}
static inline void kvm_pmu_enable_counter_mask(struct kvm_vcpu *vcpu, u64 val) {}
static inline void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_sync_hwstate(struct kvm_vcpu *vcpu) {}
static inline bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu)
{
return false;
}
static inline void kvm_pmu_update_run(struct kvm_vcpu *vcpu) {}
static inline void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val) {}
static inline void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val) {}
static inline void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu,
u64 data, u64 select_idx) {}
static inline int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
return -ENXIO;
}
static inline int kvm_arm_pmu_v3_get_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
return -ENXIO;
}
static inline int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr)
{
return -ENXIO;
}
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