linux/arch/x86/kernel/cpu/perf_event_amd.c

421 lines
9.9 KiB
C

#ifdef CONFIG_CPU_SUP_AMD
static DEFINE_RAW_SPINLOCK(amd_nb_lock);
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) ] = 0x0041, /* Data Cache Misses */
},
[ C(OP_WRITE) ] = {
[ C(RESULT_ACCESS) ] = 0x0142, /* Data Cache Refills :system */
[ 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) ] = 0x0046, /* L1 DTLB and L2 DLTB Miss */
},
[ 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) ] = 0x0085, /* Instr. fetch ITLB 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,
},
},
};
/*
* AMD Performance Monitor K7 and later.
*/
static const u64 amd_perfmon_event_map[] =
{
[PERF_COUNT_HW_CPU_CYCLES] = 0x0076,
[PERF_COUNT_HW_INSTRUCTIONS] = 0x00c0,
[PERF_COUNT_HW_CACHE_REFERENCES] = 0x0080,
[PERF_COUNT_HW_CACHE_MISSES] = 0x0081,
[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x00c2,
[PERF_COUNT_HW_BRANCH_MISSES] = 0x00c3,
};
static u64 amd_pmu_event_map(int hw_event)
{
return amd_perfmon_event_map[hw_event];
}
static int amd_pmu_hw_config(struct perf_event *event)
{
int ret = x86_pmu_hw_config(event);
if (ret)
return ret;
if (event->attr.type != PERF_TYPE_RAW)
return 0;
event->hw.config |= event->attr.config & AMD64_RAW_EVENT_MASK;
return 0;
}
/*
* AMD64 events are detected based on their event codes.
*/
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 void amd_put_event_constraints(struct cpu_hw_events *cpuc,
struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
struct amd_nb *nb = cpuc->amd_nb;
int i;
/*
* only care about NB events
*/
if (!(amd_has_nb(cpuc) && amd_is_nb_event(hwc)))
return;
/*
* 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 (nb->owners[i] == event) {
cmpxchg(nb->owners+i, event, NULL);
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_event_constraints().
*
* Non NB events are not impacted by this restriction.
*/
static struct event_constraint *
amd_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
struct amd_nb *nb = cpuc->amd_nb;
struct perf_event *old = NULL;
int max = x86_pmu.num_counters;
int i, j, k = -1;
/*
* if not NB event or no NB, then no constraints
*/
if (!(amd_has_nb(cpuc) && amd_is_nb_event(hwc)))
return &unconstrained;
/*
* 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 (i = 0; i < max; i++) {
/*
* keep track of first free slot
*/
if (k == -1 && !nb->owners[i])
k = i;
/* already present, reuse */
if (nb->owners[i] == event)
goto done;
}
/*
* not present, so grab a new slot
* starting either at:
*/
if (hwc->idx != -1) {
/* previous assignment */
i = hwc->idx;
} else if (k != -1) {
/* start from free slot found */
i = k;
} else {
/*
* event not found, no slot found in
* first pass, try again from the
* beginning
*/
i = 0;
}
j = i;
do {
old = cmpxchg(nb->owners+i, NULL, event);
if (!old)
break;
if (++i == max)
i = 0;
} while (i != j);
done:
if (!old)
return &nb->event_constraints[i];
return &emptyconstraint;
}
static struct amd_nb *amd_alloc_nb(int cpu, int nb_id)
{
struct amd_nb *nb;
int i;
nb = kmalloc(sizeof(struct amd_nb), GFP_KERNEL);
if (!nb)
return NULL;
memset(nb, 0, sizeof(*nb));
nb->nb_id = nb_id;
/*
* 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 (boot_cpu_data.x86_max_cores < 2)
return NOTIFY_OK;
cpuc->amd_nb = amd_alloc_nb(cpu, -1);
if (!cpuc->amd_nb)
return NOTIFY_BAD;
return NOTIFY_OK;
}
static void amd_pmu_cpu_starting(int cpu)
{
struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
struct amd_nb *nb;
int i, nb_id;
if (boot_cpu_data.x86_max_cores < 2)
return;
nb_id = amd_get_nb_id(cpu);
WARN_ON_ONCE(nb_id == BAD_APICID);
raw_spin_lock(&amd_nb_lock);
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) {
kfree(cpuc->amd_nb);
cpuc->amd_nb = nb;
break;
}
}
cpuc->amd_nb->nb_id = nb_id;
cpuc->amd_nb->refcnt++;
raw_spin_unlock(&amd_nb_lock);
}
static void amd_pmu_cpu_dead(int cpu)
{
struct cpu_hw_events *cpuhw;
if (boot_cpu_data.x86_max_cores < 2)
return;
cpuhw = &per_cpu(cpu_hw_events, cpu);
raw_spin_lock(&amd_nb_lock);
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;
}
raw_spin_unlock(&amd_nb_lock);
}
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,
.event_map = amd_pmu_event_map,
.max_events = ARRAY_SIZE(amd_perfmon_event_map),
.num_counters = 4,
.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,
.cpu_prepare = amd_pmu_cpu_prepare,
.cpu_starting = amd_pmu_cpu_starting,
.cpu_dead = amd_pmu_cpu_dead,
};
static __init int amd_pmu_init(void)
{
/* Performance-monitoring supported from K7 and later: */
if (boot_cpu_data.x86 < 6)
return -ENODEV;
x86_pmu = amd_pmu;
/* Events are common for all AMDs */
memcpy(hw_cache_event_ids, amd_hw_cache_event_ids,
sizeof(hw_cache_event_ids));
return 0;
}
#else /* CONFIG_CPU_SUP_AMD */
static int amd_pmu_init(void)
{
return 0;
}
#endif