arch/x86/events/intel/uncore.c

#include "uncore.h"

static struct intel_uncore_type *empty_uncore[] = { NULL, };
struct intel_uncore_type **uncore_msr_uncores = empty_uncore;
struct intel_uncore_type **uncore_pci_uncores = empty_uncore;

static bool pcidrv_registered;
struct pci_driver *uncore_pci_driver;
/* pci bus to socket mapping */
DEFINE_RAW_SPINLOCK(pci2phy_map_lock);
struct list_head pci2phy_map_head = LIST_HEAD_INIT(pci2phy_map_head);
struct pci_dev *uncore_extra_pci_dev[UNCORE_SOCKET_MAX][UNCORE_EXTRA_PCI_DEV_MAX];

static DEFINE_RAW_SPINLOCK(uncore_box_lock);
/* mask of cpus that collect uncore events */
static cpumask_t uncore_cpu_mask;

/* constraint for the fixed counter */
static struct event_constraint uncore_constraint_fixed =
	EVENT_CONSTRAINT(~0ULL, 1 << UNCORE_PMC_IDX_FIXED, ~0ULL);
struct event_constraint uncore_constraint_empty =
	EVENT_CONSTRAINT(0, 0, 0);

static int uncore_pcibus_to_physid(struct pci_bus *bus)
{
	struct pci2phy_map *map;
	int phys_id = -1;

	raw_spin_lock(&pci2phy_map_lock);
	list_for_each_entry(map, &pci2phy_map_head, list) {
		if (map->segment == pci_domain_nr(bus)) {
			phys_id = map->pbus_to_physid[bus->number];
			break;
		}
	}
	raw_spin_unlock(&pci2phy_map_lock);

	return phys_id;
}

static void uncore_free_pcibus_map(void)
{
	struct pci2phy_map *map, *tmp;

	list_for_each_entry_safe(map, tmp, &pci2phy_map_head, list) {
		list_del(&map->list);
		kfree(map);
	}
}

struct pci2phy_map *__find_pci2phy_map(int segment)
{
	struct pci2phy_map *map, *alloc = NULL;
	int i;

	lockdep_assert_held(&pci2phy_map_lock);

lookup:
	list_for_each_entry(map, &pci2phy_map_head, list) {
		if (map->segment == segment)
			goto end;
	}

	if (!alloc) {
		raw_spin_unlock(&pci2phy_map_lock);
		alloc = kmalloc(sizeof(struct pci2phy_map), GFP_KERNEL);
		raw_spin_lock(&pci2phy_map_lock);

		if (!alloc)
			return NULL;

		goto lookup;
	}

	map = alloc;
	alloc = NULL;
	map->segment = segment;
	for (i = 0; i < 256; i++)
		map->pbus_to_physid[i] = -1;
	list_add_tail(&map->list, &pci2phy_map_head);

end:
	kfree(alloc);
	return map;
}

ssize_t uncore_event_show(struct kobject *kobj,
			  struct kobj_attribute *attr, char *buf)
{
	struct uncore_event_desc *event =
		container_of(attr, struct uncore_event_desc, attr);
	return sprintf(buf, "%s", event->config);
}

struct intel_uncore_pmu *uncore_event_to_pmu(struct perf_event *event)
{
	return container_of(event->pmu, struct intel_uncore_pmu, pmu);
}

struct intel_uncore_box *uncore_pmu_to_box(struct intel_uncore_pmu *pmu, int cpu)
{
	struct intel_uncore_box *box;

	box = *per_cpu_ptr(pmu->box, cpu);
	if (box)
		return box;

	raw_spin_lock(&uncore_box_lock);
	/* Recheck in lock to handle races. */
	if (*per_cpu_ptr(pmu->box, cpu))
		goto out;
	list_for_each_entry(box, &pmu->box_list, list) {
		if (box->phys_id == topology_physical_package_id(cpu)) {
			atomic_inc(&box->refcnt);
			*per_cpu_ptr(pmu->box, cpu) = box;
			break;
		}
	}
out:
	raw_spin_unlock(&uncore_box_lock);

	return *per_cpu_ptr(pmu->box, cpu);
}

struct intel_uncore_box *uncore_event_to_box(struct perf_event *event)
{
	/*
	 * perf core schedules event on the basis of cpu, uncore events are
	 * collected by one of the cpus inside a physical package.
	 */
	return uncore_pmu_to_box(uncore_event_to_pmu(event), smp_processor_id());
}

u64 uncore_msr_read_counter(struct intel_uncore_box *box, struct perf_event *event)
{
	u64 count;

	rdmsrl(event->hw.event_base, count);

	return count;
}

/*
 * generic get constraint function for shared match/mask registers.
 */
struct event_constraint *
uncore_get_constraint(struct intel_uncore_box *box, struct perf_event *event)
{
	struct intel_uncore_extra_reg *er;
	struct hw_perf_event_extra *reg1 = &event->hw.extra_reg;
	struct hw_perf_event_extra *reg2 = &event->hw.branch_reg;
	unsigned long flags;
	bool ok = false;

	/*
	 * reg->alloc can be set due to existing state, so for fake box we
	 * need to ignore this, otherwise we might fail to allocate proper
	 * fake state for this extra reg constraint.
	 */
	if (reg1->idx == EXTRA_REG_NONE ||
	    (!uncore_box_is_fake(box) && reg1->alloc))
		return NULL;

	er = &box->shared_regs[reg1->idx];
	raw_spin_lock_irqsave(&er->lock, flags);
	if (!atomic_read(&er->ref) ||
	    (er->config1 == reg1->config && er->config2 == reg2->config)) {
		atomic_inc(&er->ref);
		er->config1 = reg1->config;
		er->config2 = reg2->config;
		ok = true;
	}
	raw_spin_unlock_irqrestore(&er->lock, flags);

	if (ok) {
		if (!uncore_box_is_fake(box))
			reg1->alloc = 1;
		return NULL;
	}

	return &uncore_constraint_empty;
}

void uncore_put_constraint(struct intel_uncore_box *box, struct perf_event *event)
{
	struct intel_uncore_extra_reg *er;
	struct hw_perf_event_extra *reg1 = &event->hw.extra_reg;

	/*
	 * Only put constraint if extra reg was actually allocated. Also
	 * takes care of event which do not use an extra shared reg.
	 *
	 * Also, if this is a fake box we shouldn't touch any event state
	 * (reg->alloc) and we don't care about leaving inconsistent box
	 * state either since it will be thrown out.
	 */
	if (uncore_box_is_fake(box) || !reg1->alloc)
		return;

	er = &box->shared_regs[reg1->idx];
	atomic_dec(&er->ref);
	reg1->alloc = 0;
}

u64 uncore_shared_reg_config(struct intel_uncore_box *box, int idx)
{
	struct intel_uncore_extra_reg *er;
	unsigned long flags;
	u64 config;

	er = &box->shared_regs[idx];

	raw_spin_lock_irqsave(&er->lock, flags);
	config = er->config;
	raw_spin_unlock_irqrestore(&er->lock, flags);

	return config;
}

static void uncore_assign_hw_event(struct intel_uncore_box *box,
				   struct perf_event *event, int idx)
{
	struct hw_perf_event *hwc = &event->hw;

	hwc->idx = idx;
	hwc->last_tag = ++box->tags[idx];

	if (hwc->idx == UNCORE_PMC_IDX_FIXED) {
		hwc->event_base = uncore_fixed_ctr(box);
		hwc->config_base = uncore_fixed_ctl(box);
		return;
	}

	hwc->config_base = uncore_event_ctl(box, hwc->idx);
	hwc->event_base  = uncore_perf_ctr(box, hwc->idx);
}

void uncore_perf_event_update(struct intel_uncore_box *box, struct perf_event *event)
{
	u64 prev_count, new_count, delta;
	int shift;

	if (event->hw.idx >= UNCORE_PMC_IDX_FIXED)
		shift = 64 - uncore_fixed_ctr_bits(box);
	else
		shift = 64 - uncore_perf_ctr_bits(box);

	/* the hrtimer might modify the previous event value */
again:
	prev_count = local64_read(&event->hw.prev_count);
	new_count = uncore_read_counter(box, event);
	if (local64_xchg(&event->hw.prev_count, new_count) != prev_count)
		goto again;

	delta = (new_count << shift) - (prev_count << shift);
	delta >>= shift;

	local64_add(delta, &event->count);
}

/*
 * The overflow interrupt is unavailable for SandyBridge-EP, is broken
 * for SandyBridge. So we use hrtimer to periodically poll the counter
 * to avoid overflow.
 */
static enum hrtimer_restart uncore_pmu_hrtimer(struct hrtimer *hrtimer)
{
	struct intel_uncore_box *box;
	struct perf_event *event;
	unsigned long flags;
	int bit;

	box = container_of(hrtimer, struct intel_uncore_box, hrtimer);
	if (!box->n_active || box->cpu != smp_processor_id())
		return HRTIMER_NORESTART;
	/*
	 * disable local interrupt to prevent uncore_pmu_event_start/stop
	 * to interrupt the update process
	 */
	local_irq_save(flags);

	/*
	 * handle boxes with an active event list as opposed to active
	 * counters
	 */
	list_for_each_entry(event, &box->active_list, active_entry) {
		uncore_perf_event_update(box, event);
	}

	for_each_set_bit(bit, box->active_mask, UNCORE_PMC_IDX_MAX)
		uncore_perf_event_update(box, box->events[bit]);

	local_irq_restore(flags);

	hrtimer_forward_now(hrtimer, ns_to_ktime(box->hrtimer_duration));
	return HRTIMER_RESTART;
}

void uncore_pmu_start_hrtimer(struct intel_uncore_box *box)
{
	hrtimer_start(&box->hrtimer, ns_to_ktime(box->hrtimer_duration),
		      HRTIMER_MODE_REL_PINNED);
}

void uncore_pmu_cancel_hrtimer(struct intel_uncore_box *box)
{
	hrtimer_cancel(&box->hrtimer);
}

static void uncore_pmu_init_hrtimer(struct intel_uncore_box *box)
{
	hrtimer_init(&box->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
	box->hrtimer.function = uncore_pmu_hrtimer;
}

static struct intel_uncore_box *uncore_alloc_box(struct intel_uncore_type *type,
						 int node)
{
	int i, size, numshared = type->num_shared_regs ;
	struct intel_uncore_box *box;

	size = sizeof(*box) + numshared * sizeof(struct intel_uncore_extra_reg);

	box = kzalloc_node(size, GFP_KERNEL, node);
	if (!box)
		return NULL;

	for (i = 0; i < numshared; i++)
		raw_spin_lock_init(&box->shared_regs[i].lock);

	uncore_pmu_init_hrtimer(box);
	atomic_set(&box->refcnt, 1);
	box->cpu = -1;
	box->phys_id = -1;

	/* set default hrtimer timeout */
	box->hrtimer_duration = UNCORE_PMU_HRTIMER_INTERVAL;

	INIT_LIST_HEAD(&box->active_list);

	return box;
}

/*
 * Using uncore_pmu_event_init pmu event_init callback
 * as a detection point for uncore events.
 */
static int uncore_pmu_event_init(struct perf_event *event);

static bool is_uncore_event(struct perf_event *event)
{
	return event->pmu->event_init == uncore_pmu_event_init;
}

static int
uncore_collect_events(struct intel_uncore_box *box, struct perf_event *leader,
		      bool dogrp)
{
	struct perf_event *event;
	int n, max_count;

	max_count = box->pmu->type->num_counters;
	if (box->pmu->type->fixed_ctl)
		max_count++;

	if (box->n_events >= max_count)
		return -EINVAL;

	n = box->n_events;

	if (is_uncore_event(leader)) {
		box->event_list[n] = leader;
		n++;
	}

	if (!dogrp)
		return n;

	list_for_each_entry(event, &leader->sibling_list, group_entry) {
		if (!is_uncore_event(event) ||
		    event->state <= PERF_EVENT_STATE_OFF)
			continue;

		if (n >= max_count)
			return -EINVAL;

		box->event_list[n] = event;
		n++;
	}
	return n;
}

static struct event_constraint *
uncore_get_event_constraint(struct intel_uncore_box *box, struct perf_event *event)
{
	struct intel_uncore_type *type = box->pmu->type;
	struct event_constraint *c;

	if (type->ops->get_constraint) {
		c = type->ops->get_constraint(box, event);
		if (c)
			return c;
	}

	if (event->attr.config == UNCORE_FIXED_EVENT)
		return &uncore_constraint_fixed;

	if (type->constraints) {
		for_each_event_constraint(c, type->constraints) {
			if ((event->hw.config & c->cmask) == c->code)
				return c;
		}
	}

	return &type->unconstrainted;
}

static void uncore_put_event_constraint(struct intel_uncore_box *box,
					struct perf_event *event)
{
	if (box->pmu->type->ops->put_constraint)
		box->pmu->type->ops->put_constraint(box, event);
}

static int uncore_assign_events(struct intel_uncore_box *box, int assign[], int n)
{
	unsigned long used_mask[BITS_TO_LONGS(UNCORE_PMC_IDX_MAX)];
	struct event_constraint *c;
	int i, wmin, wmax, ret = 0;
	struct hw_perf_event *hwc;

	bitmap_zero(used_mask, UNCORE_PMC_IDX_MAX);

	for (i = 0, wmin = UNCORE_PMC_IDX_MAX, wmax = 0; i < n; i++) {
		c = uncore_get_event_constraint(box, box->event_list[i]);
		box->event_constraint[i] = c;
		wmin = min(wmin, c->weight);
		wmax = max(wmax, c->weight);
	}

	/* fastpath, try to reuse previous register */
	for (i = 0; i < n; i++) {
		hwc = &box->event_list[i]->hw;
		c = box->event_constraint[i];

		/* never assigned */
		if (hwc->idx == -1)
			break;

		/* constraint still honored */
		if (!test_bit(hwc->idx, c->idxmsk))
			break;

		/* not already used */
		if (test_bit(hwc->idx, used_mask))
			break;

		__set_bit(hwc->idx, used_mask);
		if (assign)
			assign[i] = hwc->idx;
	}
	/* slow path */
	if (i != n)
		ret = perf_assign_events(box->event_constraint, n,
					 wmin, wmax, n, assign);

	if (!assign || ret) {
		for (i = 0; i < n; i++)
			uncore_put_event_constraint(box, box->event_list[i]);
	}
	return ret ? -EINVAL : 0;
}

static void uncore_pmu_event_start(struct perf_event *event, int flags)
{
	struct intel_uncore_box *box = uncore_event_to_box(event);
	int idx = event->hw.idx;

	if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
		return;

	if (WARN_ON_ONCE(idx == -1 || idx >= UNCORE_PMC_IDX_MAX))
		return;

	event->hw.state = 0;
	box->events[idx] = event;
	box->n_active++;
	__set_bit(idx, box->active_mask);

	local64_set(&event->hw.prev_count, uncore_read_counter(box, event));
	uncore_enable_event(box, event);

	if (box->n_active == 1) {
		uncore_enable_box(box);
		uncore_pmu_start_hrtimer(box);
	}
}

static void uncore_pmu_event_stop(struct perf_event *event, int flags)
{
	struct intel_uncore_box *box = uncore_event_to_box(event);
	struct hw_perf_event *hwc = &event->hw;

	if (__test_and_clear_bit(hwc->idx, box->active_mask)) {
		uncore_disable_event(box, event);
		box->n_active--;
		box->events[hwc->idx] = NULL;
		WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
		hwc->state |= PERF_HES_STOPPED;

		if (box->n_active == 0) {
			uncore_disable_box(box);
			uncore_pmu_cancel_hrtimer(box);
		}
	}

	if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
		/*
		 * Drain the remaining delta count out of a event
		 * that we are disabling:
		 */
		uncore_perf_event_update(box, event);
		hwc->state |= PERF_HES_UPTODATE;
	}
}

static int uncore_pmu_event_add(struct perf_event *event, int flags)
{
	struct intel_uncore_box *box = uncore_event_to_box(event);
	struct hw_perf_event *hwc = &event->hw;
	int assign[UNCORE_PMC_IDX_MAX];
	int i, n, ret;

	if (!box)
		return -ENODEV;

	ret = n = uncore_collect_events(box, event, false);
	if (ret < 0)
		return ret;

	hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
	if (!(flags & PERF_EF_START))
		hwc->state |= PERF_HES_ARCH;

	ret = uncore_assign_events(box, assign, n);
	if (ret)
		return ret;

	/* save events moving to new counters */
	for (i = 0; i < box->n_events; i++) {
		event = box->event_list[i];
		hwc = &event->hw;

		if (hwc->idx == assign[i] &&
			hwc->last_tag == box->tags[assign[i]])
			continue;
		/*
		 * Ensure we don't accidentally enable a stopped
		 * counter simply because we rescheduled.
		 */
		if (hwc->state & PERF_HES_STOPPED)
			hwc->state |= PERF_HES_ARCH;

		uncore_pmu_event_stop(event, PERF_EF_UPDATE);
	}

	/* reprogram moved events into new counters */
	for (i = 0; i < n; i++) {
		event = box->event_list[i];
		hwc = &event->hw;

		if (hwc->idx != assign[i] ||
			hwc->last_tag != box->tags[assign[i]])
			uncore_assign_hw_event(box, event, assign[i]);
		else if (i < box->n_events)
			continue;

		if (hwc->state & PERF_HES_ARCH)
			continue;

		uncore_pmu_event_start(event, 0);
	}
	box->n_events = n;

	return 0;
}

static void uncore_pmu_event_del(struct perf_event *event, int flags)
{
	struct intel_uncore_box *box = uncore_event_to_box(event);
	int i;

	uncore_pmu_event_stop(event, PERF_EF_UPDATE);

	for (i = 0; i < box->n_events; i++) {
		if (event == box->event_list[i]) {
			uncore_put_event_constraint(box, event);

			for (++i; i < box->n_events; i++)
				box->event_list[i - 1] = box->event_list[i];

			--box->n_events;
			break;
		}
	}

	event->hw.idx = -1;
	event->hw.last_tag = ~0ULL;
}

void uncore_pmu_event_read(struct perf_event *event)
{
	struct intel_uncore_box *box = uncore_event_to_box(event);
	uncore_perf_event_update(box, event);
}

/*
 * validation ensures the group can be loaded onto the
 * PMU if it was the only group available.
 */
static int uncore_validate_group(struct intel_uncore_pmu *pmu,
				struct perf_event *event)
{
	struct perf_event *leader = event->group_leader;
	struct intel_uncore_box *fake_box;
	int ret = -EINVAL, n;

	fake_box = uncore_alloc_box(pmu->type, NUMA_NO_NODE);
	if (!fake_box)
		return -ENOMEM;

	fake_box->pmu = pmu;
	/*
	 * the event is not yet connected with its
	 * siblings therefore we must first collect
	 * existing siblings, then add the new event
	 * before we can simulate the scheduling
	 */
	n = uncore_collect_events(fake_box, leader, true);
	if (n < 0)
		goto out;

	fake_box->n_events = n;
	n = uncore_collect_events(fake_box, event, false);
	if (n < 0)
		goto out;

	fake_box->n_events = n;

	ret = uncore_assign_events(fake_box, NULL, n);
out:
	kfree(fake_box);
	return ret;
}

static int uncore_pmu_event_init(struct perf_event *event)
{
	struct intel_uncore_pmu *pmu;
	struct intel_uncore_box *box;
	struct hw_perf_event *hwc = &event->hw;
	int ret;

	if (event->attr.type != event->pmu->type)
		return -ENOENT;

	pmu = uncore_event_to_pmu(event);
	/* no device found for this pmu */
	if (pmu->func_id < 0)
		return -ENOENT;

	/*
	 * Uncore PMU does measure at all privilege level all the time.
	 * So it doesn't make sense to specify any exclude bits.
	 */
	if (event->attr.exclude_user || event->attr.exclude_kernel ||
			event->attr.exclude_hv || event->attr.exclude_idle)
		return -EINVAL;

	/* Sampling not supported yet */
	if (hwc->sample_period)
		return -EINVAL;

	/*
	 * Place all uncore events for a particular physical package
	 * onto a single cpu
	 */
	if (event->cpu < 0)
		return -EINVAL;
	box = uncore_pmu_to_box(pmu, event->cpu);
	if (!box || box->cpu < 0)
		return -EINVAL;
	event->cpu = box->cpu;

	event->hw.idx = -1;
	event->hw.last_tag = ~0ULL;
	event->hw.extra_reg.idx = EXTRA_REG_NONE;
	event->hw.branch_reg.idx = EXTRA_REG_NONE;

	if (event->attr.config == UNCORE_FIXED_EVENT) {
		/* no fixed counter */
		if (!pmu->type->fixed_ctl)
			return -EINVAL;
		/*
		 * if there is only one fixed counter, only the first pmu
		 * can access the fixed counter
		 */
		if (pmu->type->single_fixed && pmu->pmu_idx > 0)
			return -EINVAL;

		/* fixed counters have event field hardcoded to zero */
		hwc->config = 0ULL;
	} else {
		hwc->config = event->attr.config & pmu->type->event_mask;
		if (pmu->type->ops->hw_config) {
			ret = pmu->type->ops->hw_config(box, event);
			if (ret)
				return ret;
		}
	}

	if (event->group_leader != event)
		ret = uncore_validate_group(pmu, event);
	else
		ret = 0;

	return ret;
}

static ssize_t uncore_get_attr_cpumask(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	return cpumap_print_to_pagebuf(true, buf, &uncore_cpu_mask);
}

static DEVICE_ATTR(cpumask, S_IRUGO, uncore_get_attr_cpumask, NULL);

static struct attribute *uncore_pmu_attrs[] = {
	&dev_attr_cpumask.attr,
	NULL,
};

static struct attribute_group uncore_pmu_attr_group = {
	.attrs = uncore_pmu_attrs,
};

static int uncore_pmu_register(struct intel_uncore_pmu *pmu)
{
	int ret;

	if (!pmu->type->pmu) {
		pmu->pmu = (struct pmu) {
			.attr_groups	= pmu->type->attr_groups,
			.task_ctx_nr	= perf_invalid_context,
			.event_init	= uncore_pmu_event_init,
			.add		= uncore_pmu_event_add,
			.del		= uncore_pmu_event_del,
			.start		= uncore_pmu_event_start,
			.stop		= uncore_pmu_event_stop,
			.read		= uncore_pmu_event_read,
		};
	} else {
		pmu->pmu = *pmu->type->pmu;
		pmu->pmu.attr_groups = pmu->type->attr_groups;
	}

	if (pmu->type->num_boxes == 1) {
		if (strlen(pmu->type->name) > 0)
			sprintf(pmu->name, "uncore_%s", pmu->type->name);
		else
			sprintf(pmu->name, "uncore");
	} else {
		sprintf(pmu->name, "uncore_%s_%d", pmu->type->name,
			pmu->pmu_idx);
	}

	ret = perf_pmu_register(&pmu->pmu, pmu->name, -1);
	if (!ret)
		pmu->registered = true;
	return ret;
}

static void uncore_pmu_unregister(struct intel_uncore_pmu *pmu)
{
	if (!pmu->registered)
		return;
	perf_pmu_unregister(&pmu->pmu);
	pmu->registered = false;
}

static void __init uncore_type_exit(struct intel_uncore_type *type)
{
	int i;

	if (type->pmus) {
		for (i = 0; i < type->num_boxes; i++) {
			uncore_pmu_unregister(&type->pmus[i]);
			free_percpu(type->pmus[i].box);
		}
		kfree(type->pmus);
		type->pmus = NULL;
	}
	kfree(type->events_group);
	type->events_group = NULL;
}

static void __init uncore_types_exit(struct intel_uncore_type **types)
{
	for (; *types; types++)
		uncore_type_exit(*types);
}

static int __init uncore_type_init(struct intel_uncore_type *type)
{
	struct intel_uncore_pmu *pmus;
	struct attribute_group *attr_group;
	struct attribute **attrs;
	int i, j;

	pmus = kzalloc(sizeof(*pmus) * type->num_boxes, GFP_KERNEL);
	if (!pmus)
		return -ENOMEM;

	type->pmus = pmus;

	type->unconstrainted = (struct event_constraint)
		__EVENT_CONSTRAINT(0, (1ULL << type->num_counters) - 1,
				0, type->num_counters, 0, 0);

	for (i = 0; i < type->num_boxes; i++) {
		pmus[i].func_id = -1;
		pmus[i].pmu_idx = i;
		pmus[i].type = type;
		INIT_LIST_HEAD(&pmus[i].box_list);
		pmus[i].box = alloc_percpu(struct intel_uncore_box *);
		if (!pmus[i].box)
			return -ENOMEM;
	}

	if (type->event_descs) {
		i = 0;
		while (type->event_descs[i].attr.attr.name)
			i++;

		attr_group = kzalloc(sizeof(struct attribute *) * (i + 1) +
					sizeof(*attr_group), GFP_KERNEL);
		if (!attr_group)
			return -ENOMEM;

		attrs = (struct attribute **)(attr_group + 1);
		attr_group->name = "events";
		attr_group->attrs = attrs;

		for (j = 0; j < i; j++)
			attrs[j] = &type->event_descs[j].attr.attr;

		type->events_group = attr_group;
	}

	type->pmu_group = &uncore_pmu_attr_group;
	return 0;
}

static int __init uncore_types_init(struct intel_uncore_type **types)
{
	int i, ret;

	for (i = 0; types[i]; i++) {
		ret = uncore_type_init(types[i]);
		if (ret)
			return ret;
	}
	return 0;
}

/*
 * add a pci uncore device
 */
static int uncore_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
	struct intel_uncore_pmu *pmu;
	struct intel_uncore_box *box;
	struct intel_uncore_type *type;
	bool first_box = false;
	int phys_id, ret;

	phys_id = uncore_pcibus_to_physid(pdev->bus);
	if (phys_id < 0 || phys_id >= UNCORE_SOCKET_MAX)
		return -ENODEV;

	if (UNCORE_PCI_DEV_TYPE(id->driver_data) == UNCORE_EXTRA_PCI_DEV) {
		int idx = UNCORE_PCI_DEV_IDX(id->driver_data);
		uncore_extra_pci_dev[phys_id][idx] = pdev;
		pci_set_drvdata(pdev, NULL);
		return 0;
	}

	type = uncore_pci_uncores[UNCORE_PCI_DEV_TYPE(id->driver_data)];
	box = uncore_alloc_box(type, NUMA_NO_NODE);
	if (!box)
		return -ENOMEM;

	/*
	 * for performance monitoring unit with multiple boxes,
	 * each box has a different function id.
	 */
	pmu = &type->pmus[UNCORE_PCI_DEV_IDX(id->driver_data)];
	/* Knights Landing uses a common PCI device ID for multiple instances of
	 * an uncore PMU device type. There is only one entry per device type in
	 * the knl_uncore_pci_ids table inspite of multiple devices present for
	 * some device types. Hence PCI device idx would be 0 for all devices.
	 * So increment pmu pointer to point to an unused array element.
	 */
	if (boot_cpu_data.x86_model == 87) {
		while (pmu->func_id >= 0)
			pmu++;
	}

	if (pmu->func_id < 0)
		pmu->func_id = pdev->devfn;
	else
		WARN_ON_ONCE(pmu->func_id != pdev->devfn);

	box->phys_id = phys_id;
	box->pci_dev = pdev;
	box->pmu = pmu;
	uncore_box_init(box);
	pci_set_drvdata(pdev, box);

	raw_spin_lock(&uncore_box_lock);
	if (list_empty(&pmu->box_list))
		first_box = true;
	list_add_tail(&box->list, &pmu->box_list);
	raw_spin_unlock(&uncore_box_lock);

	if (!first_box)
		return 0;

	ret = uncore_pmu_register(pmu);
	if (ret) {
		pci_set_drvdata(pdev, NULL);
		raw_spin_lock(&uncore_box_lock);
		list_del(&box->list);
		raw_spin_unlock(&uncore_box_lock);
		uncore_box_exit(box);
		kfree(box);
	}
	return ret;
}

static void uncore_pci_remove(struct pci_dev *pdev)
{
	struct intel_uncore_box *box = pci_get_drvdata(pdev);
	struct intel_uncore_pmu *pmu;
	int i, cpu, phys_id;
	bool last_box = false;

	phys_id = uncore_pcibus_to_physid(pdev->bus);
	box = pci_get_drvdata(pdev);
	if (!box) {
		for (i = 0; i < UNCORE_EXTRA_PCI_DEV_MAX; i++) {
			if (uncore_extra_pci_dev[phys_id][i] == pdev) {
				uncore_extra_pci_dev[phys_id][i] = NULL;
				break;
			}
		}
		WARN_ON_ONCE(i >= UNCORE_EXTRA_PCI_DEV_MAX);
		return;
	}

	pmu = box->pmu;
	if (WARN_ON_ONCE(phys_id != box->phys_id))
		return;

	pci_set_drvdata(pdev, NULL);

	raw_spin_lock(&uncore_box_lock);
	list_del(&box->list);
	if (list_empty(&pmu->box_list))
		last_box = true;
	raw_spin_unlock(&uncore_box_lock);

	for_each_possible_cpu(cpu) {
		if (*per_cpu_ptr(pmu->box, cpu) == box) {
			*per_cpu_ptr(pmu->box, cpu) = NULL;
			atomic_dec(&box->refcnt);
		}
	}

	WARN_ON_ONCE(atomic_read(&box->refcnt) != 1);
	uncore_box_exit(box);
	kfree(box);

	if (last_box)
		uncore_pmu_unregister(pmu);
}

static int __init uncore_pci_init(void)
{
	int ret;

	switch (boot_cpu_data.x86_model) {
	case 45: /* Sandy Bridge-EP */
		ret = snbep_uncore_pci_init();
		break;
	case 62: /* Ivy Bridge-EP */
		ret = ivbep_uncore_pci_init();
		break;
	case 63: /* Haswell-EP */
		ret = hswep_uncore_pci_init();
		break;
	case 79: /* BDX-EP */
	case 86: /* BDX-DE */
		ret = bdx_uncore_pci_init();
		break;
	case 42: /* Sandy Bridge */
		ret = snb_uncore_pci_init();
		break;
	case 58: /* Ivy Bridge */
		ret = ivb_uncore_pci_init();
		break;
	case 60: /* Haswell */
	case 69: /* Haswell Celeron */
		ret = hsw_uncore_pci_init();
		break;
	case 61: /* Broadwell */
		ret = bdw_uncore_pci_init();
		break;
	case 87: /* Knights Landing */
		ret = knl_uncore_pci_init();
		break;
	case 94: /* SkyLake */
		ret = skl_uncore_pci_init();
		break;
	default:
		return 0;
	}

	if (ret)
		return ret;

	ret = uncore_types_init(uncore_pci_uncores);
	if (ret)
		goto err;

	uncore_pci_driver->probe = uncore_pci_probe;
	uncore_pci_driver->remove = uncore_pci_remove;

	ret = pci_register_driver(uncore_pci_driver);
	if (ret)
		goto err;

	pcidrv_registered = true;
	return 0;

err:
	uncore_types_exit(uncore_pci_uncores);
	uncore_pci_uncores = empty_uncore;
	uncore_free_pcibus_map();
	return ret;
}

static void __init uncore_pci_exit(void)
{
	if (pcidrv_registered) {
		pcidrv_registered = false;
		pci_unregister_driver(uncore_pci_driver);
		uncore_types_exit(uncore_pci_uncores);
		uncore_free_pcibus_map();
	}
}

/* CPU hot plug/unplug are serialized by cpu_add_remove_lock mutex */
static LIST_HEAD(boxes_to_free);

static void uncore_kfree_boxes(void)
{
	struct intel_uncore_box *box;

	while (!list_empty(&boxes_to_free)) {
		box = list_entry(boxes_to_free.next,
				 struct intel_uncore_box, list);
		list_del(&box->list);
		kfree(box);
	}
}

static void uncore_cpu_dying(int cpu)
{
	struct intel_uncore_type *type;
	struct intel_uncore_pmu *pmu;
	struct intel_uncore_box *box;
	int i, j;

	for (i = 0; uncore_msr_uncores[i]; i++) {
		type = uncore_msr_uncores[i];
		for (j = 0; j < type->num_boxes; j++) {
			pmu = &type->pmus[j];
			box = *per_cpu_ptr(pmu->box, cpu);
			*per_cpu_ptr(pmu->box, cpu) = NULL;
			if (box && atomic_dec_and_test(&box->refcnt)) {
				list_add(&box->list, &boxes_to_free);
				uncore_box_exit(box);
			}
		}
	}
}

static int uncore_cpu_starting(int cpu)
{
	struct intel_uncore_type *type;
	struct intel_uncore_pmu *pmu;
	struct intel_uncore_box *box, *exist;
	int i, j, k, phys_id;

	phys_id = topology_physical_package_id(cpu);

	for (i = 0; uncore_msr_uncores[i]; i++) {
		type = uncore_msr_uncores[i];
		for (j = 0; j < type->num_boxes; j++) {
			pmu = &type->pmus[j];
			box = *per_cpu_ptr(pmu->box, cpu);
			/* called by uncore_cpu_init? */
			if (box && box->phys_id >= 0) {
				uncore_box_init(box);
				continue;
			}

			for_each_online_cpu(k) {
				exist = *per_cpu_ptr(pmu->box, k);
				if (exist && exist->phys_id == phys_id) {
					atomic_inc(&exist->refcnt);
					*per_cpu_ptr(pmu->box, cpu) = exist;
					if (box) {
						list_add(&box->list,
							 &boxes_to_free);
						box = NULL;
					}
					break;
				}
			}

			if (box) {
				box->phys_id = phys_id;
				uncore_box_init(box);
			}
		}
	}
	return 0;
}

static int uncore_cpu_prepare(int cpu, int phys_id)
{
	struct intel_uncore_type *type;
	struct intel_uncore_pmu *pmu;
	struct intel_uncore_box *box;
	int i, j;

	for (i = 0; uncore_msr_uncores[i]; i++) {
		type = uncore_msr_uncores[i];
		for (j = 0; j < type->num_boxes; j++) {
			pmu = &type->pmus[j];
			if (pmu->func_id < 0)
				pmu->func_id = j;

			box = uncore_alloc_box(type, cpu_to_node(cpu));
			if (!box)
				return -ENOMEM;

			box->pmu = pmu;
			box->phys_id = phys_id;
			*per_cpu_ptr(pmu->box, cpu) = box;
		}
	}
	return 0;
}

static void uncore_change_type_ctx(struct intel_uncore_type *type, int old_cpu,
				   int new_cpu)
{
	struct intel_uncore_pmu *pmu = type->pmus;
	struct intel_uncore_box *box;
	int i;

	for (i = 0; i < type->num_boxes; i++, pmu++) {
		if (old_cpu < 0)
			box = uncore_pmu_to_box(pmu, new_cpu);
		else
			box = uncore_pmu_to_box(pmu, old_cpu);
		if (!box)
			continue;

		if (old_cpu < 0) {
			WARN_ON_ONCE(box->cpu != -1);
			box->cpu = new_cpu;
			continue;
		}

		WARN_ON_ONCE(box->cpu != old_cpu);
		box->cpu = -1;
		if (new_cpu < 0)
			continue;

		uncore_pmu_cancel_hrtimer(box);
		perf_pmu_migrate_context(&pmu->pmu, old_cpu, new_cpu);
		box->cpu = new_cpu;
	}
}

static void uncore_change_context(struct intel_uncore_type **uncores,
				  int old_cpu, int new_cpu)
{
	for (; *uncores; uncores++)
		uncore_change_type_ctx(*uncores, old_cpu, new_cpu);
}

static void uncore_event_exit_cpu(int cpu)
{
	int i, phys_id, target;

	/* if exiting cpu is used for collecting uncore events */
	if (!cpumask_test_and_clear_cpu(cpu, &uncore_cpu_mask))
		return;

	/* find a new cpu to collect uncore events */
	phys_id = topology_physical_package_id(cpu);
	target = -1;
	for_each_online_cpu(i) {
		if (i == cpu)
			continue;
		if (phys_id == topology_physical_package_id(i)) {
			target = i;
			break;
		}
	}

	/* migrate uncore events to the new cpu */
	if (target >= 0)
		cpumask_set_cpu(target, &uncore_cpu_mask);

	uncore_change_context(uncore_msr_uncores, cpu, target);
	uncore_change_context(uncore_pci_uncores, cpu, target);
}

static void uncore_event_init_cpu(int cpu)
{
	int i, phys_id;

	phys_id = topology_physical_package_id(cpu);
	for_each_cpu(i, &uncore_cpu_mask) {
		if (phys_id == topology_physical_package_id(i))
			return;
	}

	cpumask_set_cpu(cpu, &uncore_cpu_mask);

	uncore_change_context(uncore_msr_uncores, -1, cpu);
	uncore_change_context(uncore_pci_uncores, -1, cpu);
}

static int uncore_cpu_notifier(struct notifier_block *self,
			       unsigned long action, void *hcpu)
{
	unsigned int cpu = (long)hcpu;

	/* allocate/free data structure for uncore box */
	switch (action & ~CPU_TASKS_FROZEN) {
	case CPU_UP_PREPARE:
		return notifier_from_errno(uncore_cpu_prepare(cpu, -1));
	case CPU_STARTING:
		uncore_cpu_starting(cpu);
		break;
	case CPU_UP_CANCELED:
	case CPU_DYING:
		uncore_cpu_dying(cpu);
		break;
	case CPU_ONLINE:
	case CPU_DEAD:
		uncore_kfree_boxes();
		break;
	default:
		break;
	}

	/* select the cpu that collects uncore events */
	switch (action & ~CPU_TASKS_FROZEN) {
	case CPU_DOWN_FAILED:
	case CPU_STARTING:
		uncore_event_init_cpu(cpu);
		break;
	case CPU_DOWN_PREPARE:
		uncore_event_exit_cpu(cpu);
		break;
	default:
		break;
	}

	return NOTIFY_OK;
}

static struct notifier_block uncore_cpu_nb = {
	.notifier_call	= uncore_cpu_notifier,
	/*
	 * to migrate uncore events, our notifier should be executed
	 * before perf core's notifier.
	 */
	.priority	= CPU_PRI_PERF + 1,
};

static int __init type_pmu_register(struct intel_uncore_type *type)
{
	int i, ret;

	for (i = 0; i < type->num_boxes; i++) {
		ret = uncore_pmu_register(&type->pmus[i]);
		if (ret)
			return ret;
	}
	return 0;
}

static int __init uncore_msr_pmus_register(void)
{
	struct intel_uncore_type **types = uncore_msr_uncores;
	int ret;

	for (; *types; types++) {
		ret = type_pmu_register(*types);
		if (ret)
			return ret;
	}
	return 0;
}

static int __init uncore_cpu_init(void)
{
	int ret;

	switch (boot_cpu_data.x86_model) {
	case 26: /* Nehalem */
	case 30:
	case 37: /* Westmere */
	case 44:
		nhm_uncore_cpu_init();
		break;
	case 42: /* Sandy Bridge */
	case 58: /* Ivy Bridge */
	case 60: /* Haswell */
	case 69: /* Haswell */
	case 70: /* Haswell */
	case 61: /* Broadwell */
	case 71: /* Broadwell */
		snb_uncore_cpu_init();
		break;
	case 45: /* Sandy Bridge-EP */
		snbep_uncore_cpu_init();
		break;
	case 46: /* Nehalem-EX */
	case 47: /* Westmere-EX aka. Xeon E7 */
		nhmex_uncore_cpu_init();
		break;
	case 62: /* Ivy Bridge-EP */
		ivbep_uncore_cpu_init();
		break;
	case 63: /* Haswell-EP */
		hswep_uncore_cpu_init();
		break;
	case 79: /* BDX-EP */
	case 86: /* BDX-DE */
		bdx_uncore_cpu_init();
		break;
	case 87: /* Knights Landing */
		knl_uncore_cpu_init();
		break;
	default:
		return 0;
	}

	ret = uncore_types_init(uncore_msr_uncores);
	if (ret)
		goto err;

	ret = uncore_msr_pmus_register();
	if (ret)
		goto err;
	return 0;
err:
	uncore_types_exit(uncore_msr_uncores);
	uncore_msr_uncores = empty_uncore;
	return ret;
}

static void __init uncore_cpu_setup(void *dummy)
{
	uncore_cpu_starting(smp_processor_id());
}

static int __init uncore_cpumask_init(void)
{
	int cpu, ret = 0;

	cpu_notifier_register_begin();

	for_each_online_cpu(cpu) {
		int i, phys_id = topology_physical_package_id(cpu);

		for_each_cpu(i, &uncore_cpu_mask) {
			if (phys_id == topology_physical_package_id(i)) {
				phys_id = -1;
				break;
			}
		}
		if (phys_id < 0)
			continue;

		ret = uncore_cpu_prepare(cpu, phys_id);
		if (ret)
			goto out;
		uncore_event_init_cpu(cpu);
	}
	on_each_cpu(uncore_cpu_setup, NULL, 1);

	__register_cpu_notifier(&uncore_cpu_nb);

out:
	cpu_notifier_register_done();
	return ret;
}

static int __init intel_uncore_init(void)
{
	int ret;

	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
		return -ENODEV;

	if (cpu_has_hypervisor)
		return -ENODEV;

	ret = uncore_pci_init();
	if (ret)
		return ret;
	ret = uncore_cpu_init();
	if (ret)
		goto errpci;
	ret = uncore_cpumask_init();
	if (ret)
		goto errcpu;

	return 0;

errcpu:
	uncore_types_exit(uncore_msr_uncores);
errpci:
	uncore_pci_exit();
	return ret;
}
device_initcall(intel_uncore_init);