ubuntu-linux-kernel/arch/x86/events/amd/core.c

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2024-04-01 15:06:58 +00:00
#include <linux/perf_event.h>
#include <linux/export.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <asm/apicdef.h>
#include "../perf_event.h"
static __initconst const u64 amd_hw_cache_event_ids
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
[PERF_COUNT_HW_CACHE_RESULT_MAX] =
{
[ C(L1D) ] = {
[ C(OP_READ) ] = {
[ C(RESULT_ACCESS) ] = 0x0040, /* Data Cache Accesses */
[ C(RESULT_MISS) ] = 0x0141, /* Data Cache Misses */
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = 0,
[ C(RESULT_MISS) ] = 0,
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = 0x0267, /* Data Prefetcher :attempts */
[ C(RESULT_MISS) ] = 0x0167, /* Data Prefetcher :cancelled */
},
},
[ C(L1I ) ] = {
[ C(OP_READ) ] = {
[ C(RESULT_ACCESS) ] = 0x0080, /* Instruction cache fetches */
[ C(RESULT_MISS) ] = 0x0081, /* Instruction cache misses */
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = -1,
[ C(RESULT_MISS) ] = -1,
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = 0x014B, /* Prefetch Instructions :Load */
[ C(RESULT_MISS) ] = 0,
},
},
[ C(LL ) ] = {
[ C(OP_READ) ] = {
[ C(RESULT_ACCESS) ] = 0x037D, /* Requests to L2 Cache :IC+DC */
[ C(RESULT_MISS) ] = 0x037E, /* L2 Cache Misses : IC+DC */
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = 0x017F, /* L2 Fill/Writeback */
[ C(RESULT_MISS) ] = 0,
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = 0,
[ C(RESULT_MISS) ] = 0,
},
},
[ C(DTLB) ] = {
[ C(OP_READ) ] = {
[ C(RESULT_ACCESS) ] = 0x0040, /* Data Cache Accesses */
[ C(RESULT_MISS) ] = 0x0746, /* L1_DTLB_AND_L2_DLTB_MISS.ALL */
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = 0,
[ C(RESULT_MISS) ] = 0,
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = 0,
[ C(RESULT_MISS) ] = 0,
},
},
[ C(ITLB) ] = {
[ C(OP_READ) ] = {
[ C(RESULT_ACCESS) ] = 0x0080, /* Instruction fecthes */
[ C(RESULT_MISS) ] = 0x0385, /* L1_ITLB_AND_L2_ITLB_MISS.ALL */
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = -1,
[ C(RESULT_MISS) ] = -1,
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = -1,
[ C(RESULT_MISS) ] = -1,
},
},
[ C(BPU ) ] = {
[ C(OP_READ) ] = {
[ C(RESULT_ACCESS) ] = 0x00c2, /* Retired Branch Instr. */
[ C(RESULT_MISS) ] = 0x00c3, /* Retired Mispredicted BI */
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = -1,
[ C(RESULT_MISS) ] = -1,
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = -1,
[ C(RESULT_MISS) ] = -1,
},
},
[ C(NODE) ] = {
[ C(OP_READ) ] = {
[ C(RESULT_ACCESS) ] = 0xb8e9, /* CPU Request to Memory, l+r */
[ C(RESULT_MISS) ] = 0x98e9, /* CPU Request to Memory, r */
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = -1,
[ C(RESULT_MISS) ] = -1,
},
[ C(OP_PREFETCH) ] = {
[ C(RESULT_ACCESS) ] = -1,
[ C(RESULT_MISS) ] = -1,
},
},
};
/*
* AMD Performance Monitor K7 and later.
*/
static const u64 amd_perfmon_event_map[PERF_COUNT_HW_MAX] =
{
[PERF_COUNT_HW_CPU_CYCLES] = 0x0076,
[PERF_COUNT_HW_INSTRUCTIONS] = 0x00c0,
[PERF_COUNT_HW_CACHE_REFERENCES] = 0x077d,
[PERF_COUNT_HW_CACHE_MISSES] = 0x077e,
[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x00c2,
[PERF_COUNT_HW_BRANCH_MISSES] = 0x00c3,
[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = 0x00d0, /* "Decoder empty" event */
[PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = 0x00d1, /* "Dispatch stalls" event */
};
static u64 amd_pmu_event_map(int hw_event)
{
return amd_perfmon_event_map[hw_event];
}
/*
* Previously calculated offsets
*/
static unsigned int event_offsets[X86_PMC_IDX_MAX] __read_mostly;
static unsigned int count_offsets[X86_PMC_IDX_MAX] __read_mostly;
/*
* Legacy CPUs:
* 4 counters starting at 0xc0010000 each offset by 1
*
* CPUs with core performance counter extensions:
* 6 counters starting at 0xc0010200 each offset by 2
*/
static inline int amd_pmu_addr_offset(int index, bool eventsel)
{
int offset;
if (!index)
return index;
if (eventsel)
offset = event_offsets[index];
else
offset = count_offsets[index];
if (offset)
return offset;
if (!boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
offset = index;
else
offset = index << 1;
if (eventsel)
event_offsets[index] = offset;
else
count_offsets[index] = offset;
return offset;
}
static int amd_core_hw_config(struct perf_event *event)
{
if (event->attr.exclude_host && event->attr.exclude_guest)
/*
* When HO == GO == 1 the hardware treats that as GO == HO == 0
* and will count in both modes. We don't want to count in that
* case so we emulate no-counting by setting US = OS = 0.
*/
event->hw.config &= ~(ARCH_PERFMON_EVENTSEL_USR |
ARCH_PERFMON_EVENTSEL_OS);
else if (event->attr.exclude_host)
event->hw.config |= AMD64_EVENTSEL_GUESTONLY;
else if (event->attr.exclude_guest)
event->hw.config |= AMD64_EVENTSEL_HOSTONLY;
return 0;
}
/*
* AMD64 events are detected based on their event codes.
*/
static inline unsigned int amd_get_event_code(struct hw_perf_event *hwc)
{
return ((hwc->config >> 24) & 0x0f00) | (hwc->config & 0x00ff);
}
static inline int amd_is_nb_event(struct hw_perf_event *hwc)
{
return (hwc->config & 0xe0) == 0xe0;
}
static inline int amd_has_nb(struct cpu_hw_events *cpuc)
{
struct amd_nb *nb = cpuc->amd_nb;
return nb && nb->nb_id != -1;
}
static int amd_pmu_hw_config(struct perf_event *event)
{
int ret;
/* pass precise event sampling to ibs: */
if (event->attr.precise_ip && get_ibs_caps())
return -ENOENT;
if (has_branch_stack(event))
return -EOPNOTSUPP;
ret = x86_pmu_hw_config(event);
if (ret)
return ret;
if (event->attr.type == PERF_TYPE_RAW)
event->hw.config |= event->attr.config & AMD64_RAW_EVENT_MASK;
return amd_core_hw_config(event);
}
static void __amd_put_nb_event_constraints(struct cpu_hw_events *cpuc,
struct perf_event *event)
{
struct amd_nb *nb = cpuc->amd_nb;
int i;
/*
* need to scan whole list because event may not have
* been assigned during scheduling
*
* no race condition possible because event can only
* be removed on one CPU at a time AND PMU is disabled
* when we come here
*/
for (i = 0; i < x86_pmu.num_counters; i++) {
if (cmpxchg(nb->owners + i, event, NULL) == event)
break;
}
}
/*
* AMD64 NorthBridge events need special treatment because
* counter access needs to be synchronized across all cores
* of a package. Refer to BKDG section 3.12
*
* NB events are events measuring L3 cache, Hypertransport
* traffic. They are identified by an event code >= 0xe00.
* They measure events on the NorthBride which is shared
* by all cores on a package. NB events are counted on a
* shared set of counters. When a NB event is programmed
* in a counter, the data actually comes from a shared
* counter. Thus, access to those counters needs to be
* synchronized.
*
* We implement the synchronization such that no two cores
* can be measuring NB events using the same counters. Thus,
* we maintain a per-NB allocation table. The available slot
* is propagated using the event_constraint structure.
*
* We provide only one choice for each NB event based on
* the fact that only NB events have restrictions. Consequently,
* if a counter is available, there is a guarantee the NB event
* will be assigned to it. If no slot is available, an empty
* constraint is returned and scheduling will eventually fail
* for this event.
*
* Note that all cores attached the same NB compete for the same
* counters to host NB events, this is why we use atomic ops. Some
* multi-chip CPUs may have more than one NB.
*
* Given that resources are allocated (cmpxchg), they must be
* eventually freed for others to use. This is accomplished by
* calling __amd_put_nb_event_constraints()
*
* Non NB events are not impacted by this restriction.
*/
static struct event_constraint *
__amd_get_nb_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event,
struct event_constraint *c)
{
struct hw_perf_event *hwc = &event->hw;
struct amd_nb *nb = cpuc->amd_nb;
struct perf_event *old;
int idx, new = -1;
if (!c)
c = &unconstrained;
if (cpuc->is_fake)
return c;
/*
* detect if already present, if so reuse
*
* cannot merge with actual allocation
* because of possible holes
*
* event can already be present yet not assigned (in hwc->idx)
* because of successive calls to x86_schedule_events() from
* hw_perf_group_sched_in() without hw_perf_enable()
*/
for_each_set_bit(idx, c->idxmsk, x86_pmu.num_counters) {
if (new == -1 || hwc->idx == idx)
/* assign free slot, prefer hwc->idx */
old = cmpxchg(nb->owners + idx, NULL, event);
else if (nb->owners[idx] == event)
/* event already present */
old = event;
else
continue;
if (old && old != event)
continue;
/* reassign to this slot */
if (new != -1)
cmpxchg(nb->owners + new, event, NULL);
new = idx;
/* already present, reuse */
if (old == event)
break;
}
if (new == -1)
return &emptyconstraint;
return &nb->event_constraints[new];
}
static struct amd_nb *amd_alloc_nb(int cpu)
{
struct amd_nb *nb;
int i;
nb = kzalloc_node(sizeof(struct amd_nb), GFP_KERNEL, cpu_to_node(cpu));
if (!nb)
return NULL;
nb->nb_id = -1;
/*
* initialize all possible NB constraints
*/
for (i = 0; i < x86_pmu.num_counters; i++) {
__set_bit(i, nb->event_constraints[i].idxmsk);
nb->event_constraints[i].weight = 1;
}
return nb;
}
static int amd_pmu_cpu_prepare(int cpu)
{
struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
WARN_ON_ONCE(cpuc->amd_nb);
if (!x86_pmu.amd_nb_constraints)
return 0;
cpuc->amd_nb = amd_alloc_nb(cpu);
if (!cpuc->amd_nb)
return -ENOMEM;
return 0;
}
static void amd_pmu_cpu_starting(int cpu)
{
struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
void **onln = &cpuc->kfree_on_online[X86_PERF_KFREE_SHARED];
struct amd_nb *nb;
int i, nb_id;
cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;
if (!x86_pmu.amd_nb_constraints)
return;
nb_id = amd_get_nb_id(cpu);
WARN_ON_ONCE(nb_id == BAD_APICID);
for_each_online_cpu(i) {
nb = per_cpu(cpu_hw_events, i).amd_nb;
if (WARN_ON_ONCE(!nb))
continue;
if (nb->nb_id == nb_id) {
*onln = cpuc->amd_nb;
cpuc->amd_nb = nb;
break;
}
}
cpuc->amd_nb->nb_id = nb_id;
cpuc->amd_nb->refcnt++;
}
static void amd_pmu_cpu_dead(int cpu)
{
struct cpu_hw_events *cpuhw;
if (!x86_pmu.amd_nb_constraints)
return;
cpuhw = &per_cpu(cpu_hw_events, cpu);
if (cpuhw->amd_nb) {
struct amd_nb *nb = cpuhw->amd_nb;
if (nb->nb_id == -1 || --nb->refcnt == 0)
kfree(nb);
cpuhw->amd_nb = NULL;
}
}
static struct event_constraint *
amd_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
struct perf_event *event)
{
/*
* if not NB event or no NB, then no constraints
*/
if (!(amd_has_nb(cpuc) && amd_is_nb_event(&event->hw)))
return &unconstrained;
return __amd_get_nb_event_constraints(cpuc, event, NULL);
}
static void amd_put_event_constraints(struct cpu_hw_events *cpuc,
struct perf_event *event)
{
if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw))
__amd_put_nb_event_constraints(cpuc, event);
}
PMU_FORMAT_ATTR(event, "config:0-7,32-35");
PMU_FORMAT_ATTR(umask, "config:8-15" );
PMU_FORMAT_ATTR(edge, "config:18" );
PMU_FORMAT_ATTR(inv, "config:23" );
PMU_FORMAT_ATTR(cmask, "config:24-31" );
static struct attribute *amd_format_attr[] = {
&format_attr_event.attr,
&format_attr_umask.attr,
&format_attr_edge.attr,
&format_attr_inv.attr,
&format_attr_cmask.attr,
NULL,
};
/* AMD Family 15h */
#define AMD_EVENT_TYPE_MASK 0x000000F0ULL
#define AMD_EVENT_FP 0x00000000ULL ... 0x00000010ULL
#define AMD_EVENT_LS 0x00000020ULL ... 0x00000030ULL
#define AMD_EVENT_DC 0x00000040ULL ... 0x00000050ULL
#define AMD_EVENT_CU 0x00000060ULL ... 0x00000070ULL
#define AMD_EVENT_IC_DE 0x00000080ULL ... 0x00000090ULL
#define AMD_EVENT_EX_LS 0x000000C0ULL
#define AMD_EVENT_DE 0x000000D0ULL
#define AMD_EVENT_NB 0x000000E0ULL ... 0x000000F0ULL
/*
* AMD family 15h event code/PMC mappings:
*
* type = event_code & 0x0F0:
*
* 0x000 FP PERF_CTL[5:3]
* 0x010 FP PERF_CTL[5:3]
* 0x020 LS PERF_CTL[5:0]
* 0x030 LS PERF_CTL[5:0]
* 0x040 DC PERF_CTL[5:0]
* 0x050 DC PERF_CTL[5:0]
* 0x060 CU PERF_CTL[2:0]
* 0x070 CU PERF_CTL[2:0]
* 0x080 IC/DE PERF_CTL[2:0]
* 0x090 IC/DE PERF_CTL[2:0]
* 0x0A0 ---
* 0x0B0 ---
* 0x0C0 EX/LS PERF_CTL[5:0]
* 0x0D0 DE PERF_CTL[2:0]
* 0x0E0 NB NB_PERF_CTL[3:0]
* 0x0F0 NB NB_PERF_CTL[3:0]
*
* Exceptions:
*
* 0x000 FP PERF_CTL[3], PERF_CTL[5:3] (*)
* 0x003 FP PERF_CTL[3]
* 0x004 FP PERF_CTL[3], PERF_CTL[5:3] (*)
* 0x00B FP PERF_CTL[3]
* 0x00D FP PERF_CTL[3]
* 0x023 DE PERF_CTL[2:0]
* 0x02D LS PERF_CTL[3]
* 0x02E LS PERF_CTL[3,0]
* 0x031 LS PERF_CTL[2:0] (**)
* 0x043 CU PERF_CTL[2:0]
* 0x045 CU PERF_CTL[2:0]
* 0x046 CU PERF_CTL[2:0]
* 0x054 CU PERF_CTL[2:0]
* 0x055 CU PERF_CTL[2:0]
* 0x08F IC PERF_CTL[0]
* 0x187 DE PERF_CTL[0]
* 0x188 DE PERF_CTL[0]
* 0x0DB EX PERF_CTL[5:0]
* 0x0DC LS PERF_CTL[5:0]
* 0x0DD LS PERF_CTL[5:0]
* 0x0DE LS PERF_CTL[5:0]
* 0x0DF LS PERF_CTL[5:0]
* 0x1C0 EX PERF_CTL[5:3]
* 0x1D6 EX PERF_CTL[5:0]
* 0x1D8 EX PERF_CTL[5:0]
*
* (*) depending on the umask all FPU counters may be used
* (**) only one unitmask enabled at a time
*/
static struct event_constraint amd_f15_PMC0 = EVENT_CONSTRAINT(0, 0x01, 0);
static struct event_constraint amd_f15_PMC20 = EVENT_CONSTRAINT(0, 0x07, 0);
static struct event_constraint amd_f15_PMC3 = EVENT_CONSTRAINT(0, 0x08, 0);
static struct event_constraint amd_f15_PMC30 = EVENT_CONSTRAINT_OVERLAP(0, 0x09, 0);
static struct event_constraint amd_f15_PMC50 = EVENT_CONSTRAINT(0, 0x3F, 0);
static struct event_constraint amd_f15_PMC53 = EVENT_CONSTRAINT(0, 0x38, 0);
static struct event_constraint *
amd_get_event_constraints_f15h(struct cpu_hw_events *cpuc, int idx,
struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
unsigned int event_code = amd_get_event_code(hwc);
switch (event_code & AMD_EVENT_TYPE_MASK) {
case AMD_EVENT_FP:
switch (event_code) {
case 0x000:
if (!(hwc->config & 0x0000F000ULL))
break;
if (!(hwc->config & 0x00000F00ULL))
break;
return &amd_f15_PMC3;
case 0x004:
if (hweight_long(hwc->config & ARCH_PERFMON_EVENTSEL_UMASK) <= 1)
break;
return &amd_f15_PMC3;
case 0x003:
case 0x00B:
case 0x00D:
return &amd_f15_PMC3;
}
return &amd_f15_PMC53;
case AMD_EVENT_LS:
case AMD_EVENT_DC:
case AMD_EVENT_EX_LS:
switch (event_code) {
case 0x023:
case 0x043:
case 0x045:
case 0x046:
case 0x054:
case 0x055:
return &amd_f15_PMC20;
case 0x02D:
return &amd_f15_PMC3;
case 0x02E:
return &amd_f15_PMC30;
case 0x031:
if (hweight_long(hwc->config & ARCH_PERFMON_EVENTSEL_UMASK) <= 1)
return &amd_f15_PMC20;
return &emptyconstraint;
case 0x1C0:
return &amd_f15_PMC53;
default:
return &amd_f15_PMC50;
}
case AMD_EVENT_CU:
case AMD_EVENT_IC_DE:
case AMD_EVENT_DE:
switch (event_code) {
case 0x08F:
case 0x187:
case 0x188:
return &amd_f15_PMC0;
case 0x0DB ... 0x0DF:
case 0x1D6:
case 0x1D8:
return &amd_f15_PMC50;
default:
return &amd_f15_PMC20;
}
case AMD_EVENT_NB:
/* moved to uncore.c */
return &emptyconstraint;
default:
return &emptyconstraint;
}
}
static ssize_t amd_event_sysfs_show(char *page, u64 config)
{
u64 event = (config & ARCH_PERFMON_EVENTSEL_EVENT) |
(config & AMD64_EVENTSEL_EVENT) >> 24;
return x86_event_sysfs_show(page, config, event);
}
static __initconst const struct x86_pmu amd_pmu = {
.name = "AMD",
.handle_irq = x86_pmu_handle_irq,
.disable_all = x86_pmu_disable_all,
.enable_all = x86_pmu_enable_all,
.enable = x86_pmu_enable_event,
.disable = x86_pmu_disable_event,
.hw_config = amd_pmu_hw_config,
.schedule_events = x86_schedule_events,
.eventsel = MSR_K7_EVNTSEL0,
.perfctr = MSR_K7_PERFCTR0,
.addr_offset = amd_pmu_addr_offset,
.event_map = amd_pmu_event_map,
.max_events = ARRAY_SIZE(amd_perfmon_event_map),
.num_counters = AMD64_NUM_COUNTERS,
.cntval_bits = 48,
.cntval_mask = (1ULL << 48) - 1,
.apic = 1,
/* use highest bit to detect overflow */
.max_period = (1ULL << 47) - 1,
.get_event_constraints = amd_get_event_constraints,
.put_event_constraints = amd_put_event_constraints,
.format_attrs = amd_format_attr,
.events_sysfs_show = amd_event_sysfs_show,
.cpu_prepare = amd_pmu_cpu_prepare,
.cpu_starting = amd_pmu_cpu_starting,
.cpu_dead = amd_pmu_cpu_dead,
.amd_nb_constraints = 1,
};
static int __init amd_core_pmu_init(void)
{
if (!boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
return 0;
switch (boot_cpu_data.x86) {
case 0x15:
pr_cont("Fam15h ");
x86_pmu.get_event_constraints = amd_get_event_constraints_f15h;
break;
case 0x17:
pr_cont("Fam17h ");
/*
* In family 17h, there are no event constraints in the PMC hardware.
* We fallback to using default amd_get_event_constraints.
*/
break;
default:
pr_err("core perfctr but no constraints; unknown hardware!\n");
return -ENODEV;
}
/*
* If core performance counter extensions exists, we must use
* MSR_F15H_PERF_CTL/MSR_F15H_PERF_CTR msrs. See also
* amd_pmu_addr_offset().
*/
x86_pmu.eventsel = MSR_F15H_PERF_CTL;
x86_pmu.perfctr = MSR_F15H_PERF_CTR;
x86_pmu.num_counters = AMD64_NUM_COUNTERS_CORE;
/*
* AMD Core perfctr has separate MSRs for the NB events, see
* the amd/uncore.c driver.
*/
x86_pmu.amd_nb_constraints = 0;
pr_cont("core perfctr, ");
return 0;
}
__init int amd_pmu_init(void)
{
int ret;
/* Performance-monitoring supported from K7 and later: */
if (boot_cpu_data.x86 < 6)
return -ENODEV;
x86_pmu = amd_pmu;
ret = amd_core_pmu_init();
if (ret)
return ret;
if (num_possible_cpus() == 1) {
/*
* No point in allocating data structures to serialize
* against other CPUs, when there is only the one CPU.
*/
x86_pmu.amd_nb_constraints = 0;
}
/* Events are common for all AMDs */
memcpy(hw_cache_event_ids, amd_hw_cache_event_ids,
sizeof(hw_cache_event_ids));
return 0;
}
void amd_pmu_enable_virt(void)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
cpuc->perf_ctr_virt_mask = 0;
/* Reload all events */
x86_pmu_disable_all();
x86_pmu_enable_all(0);
}
EXPORT_SYMBOL_GPL(amd_pmu_enable_virt);
void amd_pmu_disable_virt(void)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
/*
* We only mask out the Host-only bit so that host-only counting works
* when SVM is disabled. If someone sets up a guest-only counter when
* SVM is disabled the Guest-only bits still gets set and the counter
* will not count anything.
*/
cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;
/* Reload all events */
x86_pmu_disable_all();
x86_pmu_enable_all(0);
}
EXPORT_SYMBOL_GPL(amd_pmu_disable_virt);