linux-stable/arch/x86/events/amd/core.c
Breno Leitao 599522d9d2 perf/x86/amd: Do not WARN() on every IRQ
Zen 4 systems running buggy microcode can hit a WARN_ON() in the PMI
handler, as shown below, several times while perf runs. A simple
`perf top` run is enough to render the system unusable:

  WARNING: CPU: 18 PID: 20608 at arch/x86/events/amd/core.c:944 amd_pmu_v2_handle_irq+0x1be/0x2b0

This happens because the Performance Counter Global Status Register
(PerfCntGlobalStatus) has one or more bits set which are considered
reserved according to the "AMD64 Architecture Programmer’s Manual,
Volume 2: System Programming, 24593":

  https://www.amd.com/system/files/TechDocs/24593.pdf

To make this less intrusive, warn just once if any reserved bit is set
and prompt the user to update the microcode. Also sanitize the value to
what the code is handling, so that the overflow events continue to be
handled for the number of counters that are known to be sane.

Going forward, the following microcode patch levels are recommended
for Zen 4 processors in order to avoid such issues with reserved bits:

  Family=0x19 Model=0x11 Stepping=0x01: Patch=0x0a10113e
  Family=0x19 Model=0x11 Stepping=0x02: Patch=0x0a10123e
  Family=0x19 Model=0xa0 Stepping=0x01: Patch=0x0aa00116
  Family=0x19 Model=0xa0 Stepping=0x02: Patch=0x0aa00212

Commit f2eb058afc57 ("linux-firmware: Update AMD cpu microcode") from
the linux-firmware tree has binaries that meet the minimum required
patch levels.

  [ sandipan: - add message to prompt users to update microcode
              - rework commit message and call out required microcode levels ]

Fixes: 7685665c39 ("perf/x86/amd/core: Add PerfMonV2 overflow handling")
Reported-by: Jirka Hladky <jhladky@redhat.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/all/3540f985652f41041e54ee82aa53e7dbd55739ae.1694696888.git.sandipan.das@amd.com/
2023-09-25 11:30:31 +02:00

1519 lines
39 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/perf_event.h>
#include <linux/jump_label.h>
#include <linux/export.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/jiffies.h>
#include <asm/apicdef.h>
#include <asm/apic.h>
#include <asm/nmi.h>
#include "../perf_event.h"
static DEFINE_PER_CPU(unsigned long, perf_nmi_tstamp);
static unsigned long perf_nmi_window;
/* AMD Event 0xFFF: Merge. Used with Large Increment per Cycle events */
#define AMD_MERGE_EVENT ((0xFULL << 32) | 0xFFULL)
#define AMD_MERGE_EVENT_ENABLE (AMD_MERGE_EVENT | ARCH_PERFMON_EVENTSEL_ENABLE)
/* PMC Enable and Overflow bits for PerfCntrGlobal* registers */
static u64 amd_pmu_global_cntr_mask __read_mostly;
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,
},
},
};
static __initconst const u64 amd_hw_cache_event_ids_f17h
[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)] = 0xc860, /* L2$ access from DC Miss */
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = 0,
[C(RESULT_MISS)] = 0,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = 0xff5a, /* h/w prefetch DC Fills */
[C(RESULT_MISS)] = 0,
},
},
[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)] = 0,
[C(RESULT_MISS)] = 0,
},
},
[C(LL)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = 0,
[C(RESULT_MISS)] = 0,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = 0,
[C(RESULT_MISS)] = 0,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = 0,
[C(RESULT_MISS)] = 0,
},
},
[C(DTLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = 0xff45, /* All L2 DTLB accesses */
[C(RESULT_MISS)] = 0xf045, /* L2 DTLB misses (PT walks) */
},
[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)] = 0x0084, /* L1 ITLB misses, L2 ITLB hits */
[C(RESULT_MISS)] = 0xff85, /* L1 ITLB misses, L2 misses */
},
[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)] = 0,
[C(RESULT_MISS)] = 0,
},
[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, up to and including Family 16h:
*/
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 */
};
/*
* AMD Performance Monitor Family 17h and later:
*/
static const u64 amd_f17h_perfmon_event_map[PERF_COUNT_HW_MAX] =
{
[PERF_COUNT_HW_CPU_CYCLES] = 0x0076,
[PERF_COUNT_HW_INSTRUCTIONS] = 0x00c0,
[PERF_COUNT_HW_CACHE_REFERENCES] = 0xff60,
[PERF_COUNT_HW_CACHE_MISSES] = 0x0964,
[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x00c2,
[PERF_COUNT_HW_BRANCH_MISSES] = 0x00c3,
[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = 0x0287,
[PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = 0x0187,
};
static u64 amd_pmu_event_map(int hw_event)
{
if (boot_cpu_data.x86 >= 0x17)
return amd_f17h_perfmon_event_map[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;
}
/*
* 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 bool amd_is_pair_event_code(struct hw_perf_event *hwc)
{
if (!(x86_pmu.flags & PMU_FL_PAIR))
return false;
switch (amd_get_event_code(hwc)) {
case 0x003: return true; /* Retired SSE/AVX FLOPs */
default: return false;
}
}
DEFINE_STATIC_CALL_RET0(amd_pmu_branch_hw_config, *x86_pmu.hw_config);
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;
if ((x86_pmu.flags & PMU_FL_PAIR) && amd_is_pair_event_code(&event->hw))
event->hw.flags |= PERF_X86_EVENT_PAIR;
if (has_branch_stack(event))
return static_call(amd_pmu_branch_hw_config)(event);
return 0;
}
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 forward_event_to_ibs(event);
if (has_branch_stack(event) && !x86_pmu.lbr_nr)
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;
}
typedef void (amd_pmu_branch_reset_t)(void);
DEFINE_STATIC_CALL_NULL(amd_pmu_branch_reset, amd_pmu_branch_reset_t);
static void amd_pmu_cpu_reset(int cpu)
{
if (x86_pmu.lbr_nr)
static_call(amd_pmu_branch_reset)();
if (x86_pmu.version < 2)
return;
/* Clear enable bits i.e. PerfCntrGlobalCtl.PerfCntrEn */
wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_CTL, 0);
/*
* Clear freeze and overflow bits i.e. PerfCntrGLobalStatus.LbrFreeze
* and PerfCntrGLobalStatus.PerfCntrOvfl
*/
wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR,
GLOBAL_STATUS_LBRS_FROZEN | amd_pmu_global_cntr_mask);
}
static int amd_pmu_cpu_prepare(int cpu)
{
struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
cpuc->lbr_sel = kzalloc_node(sizeof(struct er_account), GFP_KERNEL,
cpu_to_node(cpu));
if (!cpuc->lbr_sel)
return -ENOMEM;
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 0;
kfree(cpuc->lbr_sel);
cpuc->lbr_sel = NULL;
return -ENOMEM;
}
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;
amd_pmu_cpu_reset(cpu);
if (!x86_pmu.amd_nb_constraints)
return;
nb_id = topology_die_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 = &per_cpu(cpu_hw_events, cpu);
kfree(cpuhw->lbr_sel);
cpuhw->lbr_sel = NULL;
amd_pmu_cpu_reset(cpu);
if (!x86_pmu.amd_nb_constraints)
return;
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 inline void amd_pmu_set_global_ctl(u64 ctl)
{
wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_CTL, ctl);
}
static inline u64 amd_pmu_get_global_status(void)
{
u64 status;
/* PerfCntrGlobalStatus is read-only */
rdmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS, status);
return status;
}
static inline void amd_pmu_ack_global_status(u64 status)
{
/*
* PerfCntrGlobalStatus is read-only but an overflow acknowledgment
* mechanism exists; writing 1 to a bit in PerfCntrGlobalStatusClr
* clears the same bit in PerfCntrGlobalStatus
*/
wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR, status);
}
static bool amd_pmu_test_overflow_topbit(int idx)
{
u64 counter;
rdmsrl(x86_pmu_event_addr(idx), counter);
return !(counter & BIT_ULL(x86_pmu.cntval_bits - 1));
}
static bool amd_pmu_test_overflow_status(int idx)
{
return amd_pmu_get_global_status() & BIT_ULL(idx);
}
DEFINE_STATIC_CALL(amd_pmu_test_overflow, amd_pmu_test_overflow_topbit);
/*
* When a PMC counter overflows, an NMI is used to process the event and
* reset the counter. NMI latency can result in the counter being updated
* before the NMI can run, which can result in what appear to be spurious
* NMIs. This function is intended to wait for the NMI to run and reset
* the counter to avoid possible unhandled NMI messages.
*/
#define OVERFLOW_WAIT_COUNT 50
static void amd_pmu_wait_on_overflow(int idx)
{
unsigned int i;
/*
* Wait for the counter to be reset if it has overflowed. This loop
* should exit very, very quickly, but just in case, don't wait
* forever...
*/
for (i = 0; i < OVERFLOW_WAIT_COUNT; i++) {
if (!static_call(amd_pmu_test_overflow)(idx))
break;
/* Might be in IRQ context, so can't sleep */
udelay(1);
}
}
static void amd_pmu_check_overflow(void)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
int idx;
/*
* This shouldn't be called from NMI context, but add a safeguard here
* to return, since if we're in NMI context we can't wait for an NMI
* to reset an overflowed counter value.
*/
if (in_nmi())
return;
/*
* Check each counter for overflow and wait for it to be reset by the
* NMI if it has overflowed. This relies on the fact that all active
* counters are always enabled when this function is called and
* ARCH_PERFMON_EVENTSEL_INT is always set.
*/
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
if (!test_bit(idx, cpuc->active_mask))
continue;
amd_pmu_wait_on_overflow(idx);
}
}
static void amd_pmu_enable_event(struct perf_event *event)
{
x86_pmu_enable_event(event);
}
static void amd_pmu_enable_all(int added)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
int idx;
amd_brs_enable_all();
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
/* only activate events which are marked as active */
if (!test_bit(idx, cpuc->active_mask))
continue;
amd_pmu_enable_event(cpuc->events[idx]);
}
}
static void amd_pmu_v2_enable_event(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
/*
* Testing cpu_hw_events.enabled should be skipped in this case unlike
* in x86_pmu_enable_event().
*
* Since cpu_hw_events.enabled is set only after returning from
* x86_pmu_start(), the PMCs must be programmed and kept ready.
* Counting starts only after x86_pmu_enable_all() is called.
*/
__x86_pmu_enable_event(hwc, ARCH_PERFMON_EVENTSEL_ENABLE);
}
static __always_inline void amd_pmu_core_enable_all(void)
{
amd_pmu_set_global_ctl(amd_pmu_global_cntr_mask);
}
static void amd_pmu_v2_enable_all(int added)
{
amd_pmu_lbr_enable_all();
amd_pmu_core_enable_all();
}
static void amd_pmu_disable_event(struct perf_event *event)
{
x86_pmu_disable_event(event);
/*
* This can be called from NMI context (via x86_pmu_stop). The counter
* may have overflowed, but either way, we'll never see it get reset
* by the NMI if we're already in the NMI. And the NMI latency support
* below will take care of any pending NMI that might have been
* generated by the overflow.
*/
if (in_nmi())
return;
amd_pmu_wait_on_overflow(event->hw.idx);
}
static void amd_pmu_disable_all(void)
{
amd_brs_disable_all();
x86_pmu_disable_all();
amd_pmu_check_overflow();
}
static __always_inline void amd_pmu_core_disable_all(void)
{
amd_pmu_set_global_ctl(0);
}
static void amd_pmu_v2_disable_all(void)
{
amd_pmu_core_disable_all();
amd_pmu_lbr_disable_all();
amd_pmu_check_overflow();
}
DEFINE_STATIC_CALL_NULL(amd_pmu_branch_add, *x86_pmu.add);
static void amd_pmu_add_event(struct perf_event *event)
{
if (needs_branch_stack(event))
static_call(amd_pmu_branch_add)(event);
}
DEFINE_STATIC_CALL_NULL(amd_pmu_branch_del, *x86_pmu.del);
static void amd_pmu_del_event(struct perf_event *event)
{
if (needs_branch_stack(event))
static_call(amd_pmu_branch_del)(event);
}
/*
* Because of NMI latency, if multiple PMC counters are active or other sources
* of NMIs are received, the perf NMI handler can handle one or more overflowed
* PMC counters outside of the NMI associated with the PMC overflow. If the NMI
* doesn't arrive at the LAPIC in time to become a pending NMI, then the kernel
* back-to-back NMI support won't be active. This PMC handler needs to take into
* account that this can occur, otherwise this could result in unknown NMI
* messages being issued. Examples of this is PMC overflow while in the NMI
* handler when multiple PMCs are active or PMC overflow while handling some
* other source of an NMI.
*
* Attempt to mitigate this by creating an NMI window in which un-handled NMIs
* received during this window will be claimed. This prevents extending the
* window past when it is possible that latent NMIs should be received. The
* per-CPU perf_nmi_tstamp will be set to the window end time whenever perf has
* handled a counter. When an un-handled NMI is received, it will be claimed
* only if arriving within that window.
*/
static inline int amd_pmu_adjust_nmi_window(int handled)
{
/*
* If a counter was handled, record a timestamp such that un-handled
* NMIs will be claimed if arriving within that window.
*/
if (handled) {
this_cpu_write(perf_nmi_tstamp, jiffies + perf_nmi_window);
return handled;
}
if (time_after(jiffies, this_cpu_read(perf_nmi_tstamp)))
return NMI_DONE;
return NMI_HANDLED;
}
static int amd_pmu_handle_irq(struct pt_regs *regs)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
int handled;
int pmu_enabled;
/*
* Save the PMU state.
* It needs to be restored when leaving the handler.
*/
pmu_enabled = cpuc->enabled;
cpuc->enabled = 0;
amd_brs_disable_all();
/* Drain BRS is in use (could be inactive) */
if (cpuc->lbr_users)
amd_brs_drain();
/* Process any counter overflows */
handled = x86_pmu_handle_irq(regs);
cpuc->enabled = pmu_enabled;
if (pmu_enabled)
amd_brs_enable_all();
return amd_pmu_adjust_nmi_window(handled);
}
static int amd_pmu_v2_handle_irq(struct pt_regs *regs)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
struct perf_sample_data data;
struct hw_perf_event *hwc;
struct perf_event *event;
int handled = 0, idx;
u64 reserved, status, mask;
bool pmu_enabled;
/*
* Save the PMU state as it needs to be restored when leaving the
* handler
*/
pmu_enabled = cpuc->enabled;
cpuc->enabled = 0;
/* Stop counting but do not disable LBR */
amd_pmu_core_disable_all();
status = amd_pmu_get_global_status();
/* Check if any overflows are pending */
if (!status)
goto done;
/* Read branch records before unfreezing */
if (status & GLOBAL_STATUS_LBRS_FROZEN) {
amd_pmu_lbr_read();
status &= ~GLOBAL_STATUS_LBRS_FROZEN;
}
reserved = status & ~amd_pmu_global_cntr_mask;
if (reserved)
pr_warn_once("Reserved PerfCntrGlobalStatus bits are set (0x%llx), please consider updating microcode\n",
reserved);
/* Clear any reserved bits set by buggy microcode */
status &= amd_pmu_global_cntr_mask;
for (idx = 0; idx < x86_pmu.num_counters; idx++) {
if (!test_bit(idx, cpuc->active_mask))
continue;
event = cpuc->events[idx];
hwc = &event->hw;
x86_perf_event_update(event);
mask = BIT_ULL(idx);
if (!(status & mask))
continue;
/* Event overflow */
handled++;
status &= ~mask;
perf_sample_data_init(&data, 0, hwc->last_period);
if (!x86_perf_event_set_period(event))
continue;
if (has_branch_stack(event))
perf_sample_save_brstack(&data, event, &cpuc->lbr_stack);
if (perf_event_overflow(event, &data, regs))
x86_pmu_stop(event, 0);
}
/*
* It should never be the case that some overflows are not handled as
* the corresponding PMCs are expected to be inactive according to the
* active_mask
*/
WARN_ON(status > 0);
/* Clear overflow and freeze bits */
amd_pmu_ack_global_status(~status);
/*
* Unmasking the LVTPC is not required as the Mask (M) bit of the LVT
* PMI entry is not set by the local APIC when a PMC overflow occurs
*/
inc_irq_stat(apic_perf_irqs);
done:
cpuc->enabled = pmu_enabled;
/* Resume counting only if PMU is active */
if (pmu_enabled)
amd_pmu_core_enable_all();
return amd_pmu_adjust_nmi_window(handled);
}
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 struct event_constraint pair_constraint;
static struct event_constraint *
amd_get_event_constraints_f17h(struct cpu_hw_events *cpuc, int idx,
struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
if (amd_is_pair_event_code(hwc))
return &pair_constraint;
return &unconstrained;
}
static void amd_put_event_constraints_f17h(struct cpu_hw_events *cpuc,
struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
if (is_counter_pair(hwc))
--cpuc->n_pair;
}
/*
* Because of the way BRS operates with an inactive and active phases, and
* the link to one counter, it is not possible to have two events using BRS
* scheduled at the same time. There would be an issue with enforcing the
* period of each one and given that the BRS saturates, it would not be possible
* to guarantee correlated content for all events. Therefore, in situations
* where multiple events want to use BRS, the kernel enforces mutual exclusion.
* Exclusion is enforced by chosing only one counter for events using BRS.
* The event scheduling logic will then automatically multiplex the
* events and ensure that at most one event is actively using BRS.
*
* The BRS counter could be any counter, but there is no constraint on Fam19h,
* therefore all counters are equal and thus we pick the first one: PMC0
*/
static struct event_constraint amd_fam19h_brs_cntr0_constraint =
EVENT_CONSTRAINT(0, 0x1, AMD64_RAW_EVENT_MASK);
static struct event_constraint amd_fam19h_brs_pair_cntr0_constraint =
__EVENT_CONSTRAINT(0, 0x1, AMD64_RAW_EVENT_MASK, 1, 0, PERF_X86_EVENT_PAIR);
static struct event_constraint *
amd_get_event_constraints_f19h(struct cpu_hw_events *cpuc, int idx,
struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
bool has_brs = has_amd_brs(hwc);
/*
* In case BRS is used with an event requiring a counter pair,
* the kernel allows it but only on counter 0 & 1 to enforce
* multiplexing requiring to protect BRS in case of multiple
* BRS users
*/
if (amd_is_pair_event_code(hwc)) {
return has_brs ? &amd_fam19h_brs_pair_cntr0_constraint
: &pair_constraint;
}
if (has_brs)
return &amd_fam19h_brs_cntr0_constraint;
return &unconstrained;
}
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 void amd_pmu_limit_period(struct perf_event *event, s64 *left)
{
/*
* Decrease period by the depth of the BRS feature to get the last N
* taken branches and approximate the desired period
*/
if (has_branch_stack(event) && *left > x86_pmu.lbr_nr)
*left -= x86_pmu.lbr_nr;
}
static __initconst const struct x86_pmu amd_pmu = {
.name = "AMD",
.handle_irq = amd_pmu_handle_irq,
.disable_all = amd_pmu_disable_all,
.enable_all = amd_pmu_enable_all,
.enable = amd_pmu_enable_event,
.disable = amd_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,
.add = amd_pmu_add_event,
.del = amd_pmu_del_event,
.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 ssize_t branches_show(struct device *cdev,
struct device_attribute *attr,
char *buf)
{
return snprintf(buf, PAGE_SIZE, "%d\n", x86_pmu.lbr_nr);
}
static DEVICE_ATTR_RO(branches);
static struct attribute *amd_pmu_branches_attrs[] = {
&dev_attr_branches.attr,
NULL,
};
static umode_t
amd_branches_is_visible(struct kobject *kobj, struct attribute *attr, int i)
{
return x86_pmu.lbr_nr ? attr->mode : 0;
}
static struct attribute_group group_caps_amd_branches = {
.name = "caps",
.attrs = amd_pmu_branches_attrs,
.is_visible = amd_branches_is_visible,
};
#ifdef CONFIG_PERF_EVENTS_AMD_BRS
EVENT_ATTR_STR(branch-brs, amd_branch_brs,
"event=" __stringify(AMD_FAM19H_BRS_EVENT)"\n");
static struct attribute *amd_brs_events_attrs[] = {
EVENT_PTR(amd_branch_brs),
NULL,
};
static umode_t
amd_brs_is_visible(struct kobject *kobj, struct attribute *attr, int i)
{
return static_cpu_has(X86_FEATURE_BRS) && x86_pmu.lbr_nr ?
attr->mode : 0;
}
static struct attribute_group group_events_amd_brs = {
.name = "events",
.attrs = amd_brs_events_attrs,
.is_visible = amd_brs_is_visible,
};
#endif /* CONFIG_PERF_EVENTS_AMD_BRS */
static const struct attribute_group *amd_attr_update[] = {
&group_caps_amd_branches,
#ifdef CONFIG_PERF_EVENTS_AMD_BRS
&group_events_amd_brs,
#endif
NULL,
};
static int __init amd_core_pmu_init(void)
{
union cpuid_0x80000022_ebx ebx;
u64 even_ctr_mask = 0ULL;
int i;
if (!boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
return 0;
/* Avoid calculating the value each time in the NMI handler */
perf_nmi_window = msecs_to_jiffies(100);
/*
* 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;
/* Check for Performance Monitoring v2 support */
if (boot_cpu_has(X86_FEATURE_PERFMON_V2)) {
ebx.full = cpuid_ebx(EXT_PERFMON_DEBUG_FEATURES);
/* Update PMU version for later usage */
x86_pmu.version = 2;
/* Find the number of available Core PMCs */
x86_pmu.num_counters = ebx.split.num_core_pmc;
amd_pmu_global_cntr_mask = (1ULL << x86_pmu.num_counters) - 1;
/* Update PMC handling functions */
x86_pmu.enable_all = amd_pmu_v2_enable_all;
x86_pmu.disable_all = amd_pmu_v2_disable_all;
x86_pmu.enable = amd_pmu_v2_enable_event;
x86_pmu.handle_irq = amd_pmu_v2_handle_irq;
static_call_update(amd_pmu_test_overflow, amd_pmu_test_overflow_status);
}
/*
* AMD Core perfctr has separate MSRs for the NB events, see
* the amd/uncore.c driver.
*/
x86_pmu.amd_nb_constraints = 0;
if (boot_cpu_data.x86 == 0x15) {
pr_cont("Fam15h ");
x86_pmu.get_event_constraints = amd_get_event_constraints_f15h;
}
if (boot_cpu_data.x86 >= 0x17) {
pr_cont("Fam17h+ ");
/*
* Family 17h and compatibles have constraints for Large
* Increment per Cycle events: they may only be assigned an
* even numbered counter that has a consecutive adjacent odd
* numbered counter following it.
*/
for (i = 0; i < x86_pmu.num_counters - 1; i += 2)
even_ctr_mask |= BIT_ULL(i);
pair_constraint = (struct event_constraint)
__EVENT_CONSTRAINT(0, even_ctr_mask, 0,
x86_pmu.num_counters / 2, 0,
PERF_X86_EVENT_PAIR);
x86_pmu.get_event_constraints = amd_get_event_constraints_f17h;
x86_pmu.put_event_constraints = amd_put_event_constraints_f17h;
x86_pmu.perf_ctr_pair_en = AMD_MERGE_EVENT_ENABLE;
x86_pmu.flags |= PMU_FL_PAIR;
}
/* LBR and BRS are mutually exclusive features */
if (!amd_pmu_lbr_init()) {
/* LBR requires flushing on context switch */
x86_pmu.sched_task = amd_pmu_lbr_sched_task;
static_call_update(amd_pmu_branch_hw_config, amd_pmu_lbr_hw_config);
static_call_update(amd_pmu_branch_reset, amd_pmu_lbr_reset);
static_call_update(amd_pmu_branch_add, amd_pmu_lbr_add);
static_call_update(amd_pmu_branch_del, amd_pmu_lbr_del);
} else if (!amd_brs_init()) {
/*
* BRS requires special event constraints and flushing on ctxsw.
*/
x86_pmu.get_event_constraints = amd_get_event_constraints_f19h;
x86_pmu.sched_task = amd_pmu_brs_sched_task;
x86_pmu.limit_period = amd_pmu_limit_period;
static_call_update(amd_pmu_branch_hw_config, amd_brs_hw_config);
static_call_update(amd_pmu_branch_reset, amd_brs_reset);
static_call_update(amd_pmu_branch_add, amd_pmu_brs_add);
static_call_update(amd_pmu_branch_del, amd_pmu_brs_del);
/*
* put_event_constraints callback same as Fam17h, set above
*/
/* branch sampling must be stopped when entering low power */
amd_brs_lopwr_init();
}
x86_pmu.attr_update = amd_attr_update;
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;
}
if (boot_cpu_data.x86 >= 0x17)
memcpy(hw_cache_event_ids, amd_hw_cache_event_ids_f17h, sizeof(hw_cache_event_ids));
else
memcpy(hw_cache_event_ids, amd_hw_cache_event_ids, sizeof(hw_cache_event_ids));
return 0;
}
static inline void amd_pmu_reload_virt(void)
{
if (x86_pmu.version >= 2) {
/*
* Clear global enable bits, reprogram the PERF_CTL
* registers with updated perf_ctr_virt_mask and then
* set global enable bits once again
*/
amd_pmu_v2_disable_all();
amd_pmu_enable_all(0);
amd_pmu_v2_enable_all(0);
return;
}
amd_pmu_disable_all();
amd_pmu_enable_all(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 */
amd_pmu_reload_virt();
}
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 */
amd_pmu_reload_virt();
}
EXPORT_SYMBOL_GPL(amd_pmu_disable_virt);