linux-stable/include/linux/perf/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

186 lines
5 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* linux/arch/arm/include/asm/pmu.h
*
* Copyright (C) 2009 picoChip Designs Ltd, Jamie Iles
*/
#ifndef __ARM_PMU_H__
#define __ARM_PMU_H__
#include <linux/interrupt.h>
#include <linux/perf_event.h>
#include <linux/platform_device.h>
#include <linux/sysfs.h>
#include <asm/cputype.h>
#ifdef CONFIG_ARM_PMU
/*
* The ARMv7 CPU PMU supports up to 32 event counters.
*/
#define ARMPMU_MAX_HWEVENTS 32
/*
* ARM PMU hw_event flags
*/
/* Event uses a 64bit counter */
#define ARMPMU_EVT_64BIT 1
#define HW_OP_UNSUPPORTED 0xFFFF
#define C(_x) PERF_COUNT_HW_CACHE_##_x
#define CACHE_OP_UNSUPPORTED 0xFFFF
#define PERF_MAP_ALL_UNSUPPORTED \
[0 ... PERF_COUNT_HW_MAX - 1] = HW_OP_UNSUPPORTED
#define PERF_CACHE_MAP_ALL_UNSUPPORTED \
[0 ... C(MAX) - 1] = { \
[0 ... C(OP_MAX) - 1] = { \
[0 ... C(RESULT_MAX) - 1] = CACHE_OP_UNSUPPORTED, \
}, \
}
/* The events for a given PMU register set. */
struct pmu_hw_events {
/*
* The events that are active on the PMU for the given index.
*/
struct perf_event *events[ARMPMU_MAX_HWEVENTS];
/*
* A 1 bit for an index indicates that the counter is being used for
* an event. A 0 means that the counter can be used.
*/
DECLARE_BITMAP(used_mask, ARMPMU_MAX_HWEVENTS);
/*
* Hardware lock to serialize accesses to PMU registers. Needed for the
* read/modify/write sequences.
*/
raw_spinlock_t pmu_lock;
/*
* When using percpu IRQs, we need a percpu dev_id. Place it here as we
* already have to allocate this struct per cpu.
*/
struct arm_pmu *percpu_pmu;
int irq;
};
enum armpmu_attr_groups {
ARMPMU_ATTR_GROUP_COMMON,
ARMPMU_ATTR_GROUP_EVENTS,
ARMPMU_ATTR_GROUP_FORMATS,
ARMPMU_ATTR_GROUP_CAPS,
ARMPMU_NR_ATTR_GROUPS
};
struct arm_pmu {
struct pmu pmu;
cpumask_t supported_cpus;
char *name;
int pmuver;
irqreturn_t (*handle_irq)(struct arm_pmu *pmu);
void (*enable)(struct perf_event *event);
void (*disable)(struct perf_event *event);
int (*get_event_idx)(struct pmu_hw_events *hw_events,
struct perf_event *event);
void (*clear_event_idx)(struct pmu_hw_events *hw_events,
struct perf_event *event);
int (*set_event_filter)(struct hw_perf_event *evt,
struct perf_event_attr *attr);
u64 (*read_counter)(struct perf_event *event);
void (*write_counter)(struct perf_event *event, u64 val);
void (*start)(struct arm_pmu *);
void (*stop)(struct arm_pmu *);
void (*reset)(void *);
int (*map_event)(struct perf_event *event);
int (*filter_match)(struct perf_event *event);
int num_events;
bool secure_access; /* 32-bit ARM only */
#define ARMV8_PMUV3_MAX_COMMON_EVENTS 0x40
DECLARE_BITMAP(pmceid_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS);
#define ARMV8_PMUV3_EXT_COMMON_EVENT_BASE 0x4000
DECLARE_BITMAP(pmceid_ext_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS);
struct platform_device *plat_device;
struct pmu_hw_events __percpu *hw_events;
struct hlist_node node;
struct notifier_block cpu_pm_nb;
/* the attr_groups array must be NULL-terminated */
const struct attribute_group *attr_groups[ARMPMU_NR_ATTR_GROUPS + 1];
/* store the PMMIR_EL1 to expose slots */
u64 reg_pmmir;
/* Only to be used by ACPI probing code */
unsigned long acpi_cpuid;
};
#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
u64 armpmu_event_update(struct perf_event *event);
int armpmu_event_set_period(struct perf_event *event);
int armpmu_map_event(struct perf_event *event,
const unsigned (*event_map)[PERF_COUNT_HW_MAX],
const unsigned (*cache_map)[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
[PERF_COUNT_HW_CACHE_RESULT_MAX],
u32 raw_event_mask);
typedef int (*armpmu_init_fn)(struct arm_pmu *);
struct pmu_probe_info {
unsigned int cpuid;
unsigned int mask;
armpmu_init_fn init;
};
#define PMU_PROBE(_cpuid, _mask, _fn) \
{ \
.cpuid = (_cpuid), \
.mask = (_mask), \
.init = (_fn), \
}
#define ARM_PMU_PROBE(_cpuid, _fn) \
PMU_PROBE(_cpuid, ARM_CPU_PART_MASK, _fn)
#define ARM_PMU_XSCALE_MASK ((0xff << 24) | ARM_CPU_XSCALE_ARCH_MASK)
#define XSCALE_PMU_PROBE(_version, _fn) \
PMU_PROBE(ARM_CPU_IMP_INTEL << 24 | _version, ARM_PMU_XSCALE_MASK, _fn)
int arm_pmu_device_probe(struct platform_device *pdev,
const struct of_device_id *of_table,
const struct pmu_probe_info *probe_table);
#ifdef CONFIG_ACPI
int arm_pmu_acpi_probe(armpmu_init_fn init_fn);
#else
static inline int arm_pmu_acpi_probe(armpmu_init_fn init_fn) { return 0; }
#endif
#ifdef CONFIG_KVM
void kvm_host_pmu_init(struct arm_pmu *pmu);
#else
#define kvm_host_pmu_init(x) do { } while(0)
#endif
/* Internal functions only for core arm_pmu code */
struct arm_pmu *armpmu_alloc(void);
struct arm_pmu *armpmu_alloc_atomic(void);
void armpmu_free(struct arm_pmu *pmu);
int armpmu_register(struct arm_pmu *pmu);
int armpmu_request_irq(int irq, int cpu);
void armpmu_free_irq(int irq, int cpu);
#define ARMV8_PMU_PDEV_NAME "armv8-pmu"
#endif /* CONFIG_ARM_PMU */
#define ARMV8_SPE_PDEV_NAME "arm,spe-v1"
#endif /* __ARM_PMU_H__ */