int weight;
};
+struct amd_nb {
+ int nb_id; /* NorthBridge id */
+ int refcnt; /* reference count */
+ struct perf_event *owners[X86_PMC_IDX_MAX];
+ struct event_constraint event_constraints[X86_PMC_IDX_MAX];
+};
+
struct cpu_hw_events {
struct perf_event *events[X86_PMC_IDX_MAX]; /* in counter order */
unsigned long active_mask[BITS_TO_LONGS(X86_PMC_IDX_MAX)];
int assign[X86_PMC_IDX_MAX]; /* event to counter assignment */
u64 tags[X86_PMC_IDX_MAX];
struct perf_event *event_list[X86_PMC_IDX_MAX]; /* in enabled order */
+ struct amd_nb *amd_nb;
};
#define __EVENT_CONSTRAINT(c, n, m, w) {\
static struct x86_pmu x86_pmu __read_mostly;
+static raw_spinlock_t amd_nb_lock;
+
static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = {
.enabled = 1,
};
static u64 amd_pmu_raw_event(u64 hw_event)
{
-#define K7_EVNTSEL_EVENT_MASK 0x7000000FFULL
+#define K7_EVNTSEL_EVENT_MASK 0xF000000FFULL
#define K7_EVNTSEL_UNIT_MASK 0x00000FF00ULL
#define K7_EVNTSEL_EDGE_MASK 0x000040000ULL
#define K7_EVNTSEL_INV_MASK 0x000800000ULL
}
static struct event_constraint unconstrained;
+static struct event_constraint emptyconstraint;
static struct event_constraint bts_constraint =
EVENT_CONSTRAINT(0, 1ULL << X86_PMC_IDX_FIXED_BTS, 0);
return &unconstrained;
}
+/*
+ * 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 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 (!(nb && 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_events; 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)
{
- return &unconstrained;
+ struct hw_perf_event *hwc = &event->hw;
+ struct amd_nb *nb = cpuc->amd_nb;
+ struct perf_event *old = NULL;
+ int max = x86_pmu.num_events;
+ int i, j, k = -1;
+
+ /*
+ * if not NB event or no NB, then no constraints
+ */
+ if (!(nb && 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 int x86_event_sched_in(struct perf_event *event,
.apic = 1,
/* use highest bit to detect overflow */
.max_period = (1ULL << 47) - 1,
- .get_event_constraints = amd_get_event_constraints
+ .get_event_constraints = amd_get_event_constraints,
+ .put_event_constraints = amd_put_event_constraints
};
static __init int p6_pmu_init(void)
return 0;
}
+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_events; i++) {
+ set_bit(i, nb->event_constraints[i].idxmsk);
+ nb->event_constraints[i].weight = 1;
+ }
+ return nb;
+}
+
+static void amd_pmu_cpu_online(int cpu)
+{
+ struct cpu_hw_events *cpu1, *cpu2;
+ struct amd_nb *nb = NULL;
+ int i, nb_id;
+
+ if (boot_cpu_data.x86_max_cores < 2)
+ return;
+
+ /*
+ * function may be called too early in the
+ * boot process, in which case nb_id is bogus
+ */
+ nb_id = amd_get_nb_id(cpu);
+ if (nb_id == BAD_APICID)
+ return;
+
+ cpu1 = &per_cpu(cpu_hw_events, cpu);
+ cpu1->amd_nb = NULL;
+
+ raw_spin_lock(&amd_nb_lock);
+
+ for_each_online_cpu(i) {
+ cpu2 = &per_cpu(cpu_hw_events, i);
+ nb = cpu2->amd_nb;
+ if (!nb)
+ continue;
+ if (nb->nb_id == nb_id)
+ goto found;
+ }
+
+ nb = amd_alloc_nb(cpu, nb_id);
+ if (!nb) {
+ pr_err("perf_events: failed NB allocation for CPU%d\n", cpu);
+ raw_spin_unlock(&amd_nb_lock);
+ return;
+ }
+found:
+ nb->refcnt++;
+ cpu1->amd_nb = nb;
+
+ raw_spin_unlock(&amd_nb_lock);
+}
+
+static void amd_pmu_cpu_offline(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->refcnt == 0)
+ kfree(cpuhw->amd_nb);
+
+ cpuhw->amd_nb = NULL;
+
+ raw_spin_unlock(&amd_nb_lock);
+}
+
static __init int amd_pmu_init(void)
{
/* Performance-monitoring supported from K7 and later: */
memcpy(hw_cache_event_ids, amd_hw_cache_event_ids,
sizeof(hw_cache_event_ids));
+ /*
+ * explicitly initialize the boot cpu, other cpus will get
+ * the cpu hotplug callbacks from smp_init()
+ */
+ amd_pmu_cpu_online(smp_processor_id());
return 0;
}
void hw_perf_event_setup_online(int cpu)
{
init_debug_store_on_cpu(cpu);
+
+ switch (boot_cpu_data.x86_vendor) {
+ case X86_VENDOR_AMD:
+ amd_pmu_cpu_online(cpu);
+ break;
+ default:
+ return;
+ }
+}
+
+void hw_perf_event_setup_offline(int cpu)
+{
+ init_debug_store_on_cpu(cpu);
+
+ switch (boot_cpu_data.x86_vendor) {
+ case X86_VENDOR_AMD:
+ amd_pmu_cpu_offline(cpu);
+ break;
+ default:
+ return;
+ }
}
projects / GitHub / moto-9609 / android_kernel_motorola_exynos9610.git / commitdiff