-static void
-armpmu_start(struct perf_event *event, int flags)
-{
- struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
- struct hw_perf_event *hwc = &event->hw;
-
- /*
- * ARM pmu always has to reprogram the period, so ignore
- * PERF_EF_RELOAD, see the comment below.
- */
- if (flags & PERF_EF_RELOAD)
- WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
-
- hwc->state = 0;
- /*
- * Set the period again. Some counters can't be stopped, so when we
- * were stopped we simply disabled the IRQ source and the counter
- * may have been left counting. If we don't do this step then we may
- * get an interrupt too soon or *way* too late if the overflow has
- * happened since disabling.
- */
- armpmu_event_set_period(event, hwc, hwc->idx);
- armpmu->enable(hwc, hwc->idx);
-}
-
-static void
-armpmu_del(struct perf_event *event, int flags)
-{
- struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
- struct pmu_hw_events *hw_events = armpmu->get_hw_events();
- struct hw_perf_event *hwc = &event->hw;
- int idx = hwc->idx;
-
- WARN_ON(idx < 0);
-
- armpmu_stop(event, PERF_EF_UPDATE);
- hw_events->events[idx] = NULL;
- clear_bit(idx, hw_events->used_mask);
-
- perf_event_update_userpage(event);
-}
-
-static int
-armpmu_add(struct perf_event *event, int flags)
-{
- struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
- struct pmu_hw_events *hw_events = armpmu->get_hw_events();
- struct hw_perf_event *hwc = &event->hw;
- int idx;
- int err = 0;
-
- perf_pmu_disable(event->pmu);
-
- /* If we don't have a space for the counter then finish early. */
- idx = armpmu->get_event_idx(hw_events, hwc);
- if (idx < 0) {
- err = idx;
- goto out;
- }
-
- /*
- * If there is an event in the counter we are going to use then make
- * sure it is disabled.
- */
- event->hw.idx = idx;
- armpmu->disable(hwc, idx);
- hw_events->events[idx] = event;
-
- hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
- if (flags & PERF_EF_START)
- armpmu_start(event, PERF_EF_RELOAD);
-
- /* Propagate our changes to the userspace mapping. */
- perf_event_update_userpage(event);
-
-out:
- perf_pmu_enable(event->pmu);
- return err;
-}
-
-static int
-validate_event(struct pmu *pmu, struct pmu_hw_events *hw_events,
- struct perf_event *event)
-{
- struct arm_pmu *armpmu;
- struct hw_perf_event fake_event = event->hw;
- struct pmu *leader_pmu = event->group_leader->pmu;
-
- if (is_software_event(event))
- return 1;
-
- /*
- * Reject groups spanning multiple HW PMUs (e.g. CPU + CCI). The
- * core perf code won't check that the pmu->ctx == leader->ctx
- * until after pmu->event_init(event).
- */
- if (event->pmu != pmu)
- return 0;
-
- if (event->pmu != leader_pmu || event->state < PERF_EVENT_STATE_OFF)
- return 1;
-
- if (event->state == PERF_EVENT_STATE_OFF && !event->attr.enable_on_exec)
- return 1;
-
- armpmu = to_arm_pmu(event->pmu);
- return armpmu->get_event_idx(hw_events, &fake_event) >= 0;
-}
-
-static int
-validate_group(struct perf_event *event)
-{
- struct perf_event *sibling, *leader = event->group_leader;
- struct pmu_hw_events fake_pmu;
- DECLARE_BITMAP(fake_used_mask, ARMPMU_MAX_HWEVENTS);
-
- /*
- * Initialise the fake PMU. We only need to populate the
- * used_mask for the purposes of validation.
- */
- memset(fake_used_mask, 0, sizeof(fake_used_mask));
- fake_pmu.used_mask = fake_used_mask;
-
- if (!validate_event(event->pmu, &fake_pmu, leader))
- return -EINVAL;
-
- list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
- if (!validate_event(event->pmu, &fake_pmu, sibling))
- return -EINVAL;
- }
-
- if (!validate_event(event->pmu, &fake_pmu, event))
- return -EINVAL;
-
- return 0;
-}
-
-static void
-armpmu_disable_percpu_irq(void *data)
-{
- unsigned int irq = *(unsigned int *)data;
- disable_percpu_irq(irq);
-}
-
-static void
-armpmu_release_hardware(struct arm_pmu *armpmu)
-{
- int irq;
- unsigned int i, irqs;
- struct platform_device *pmu_device = armpmu->plat_device;
-
- irqs = min(pmu_device->num_resources, num_possible_cpus());
- if (!irqs)
- return;
-
- irq = platform_get_irq(pmu_device, 0);
- if (irq <= 0)
- return;
-
- if (irq_is_percpu(irq)) {
- on_each_cpu(armpmu_disable_percpu_irq, &irq, 1);
- free_percpu_irq(irq, &cpu_hw_events);
- } else {
- for (i = 0; i < irqs; ++i) {
- int cpu = i;
-
- if (armpmu->irq_affinity)
- cpu = armpmu->irq_affinity[i];
-
- if (!cpumask_test_and_clear_cpu(cpu, &armpmu->active_irqs))
- continue;
- irq = platform_get_irq(pmu_device, i);
- if (irq > 0)
- free_irq(irq, armpmu);
- }
- }
-}
-
-static void
-armpmu_enable_percpu_irq(void *data)
-{
- unsigned int irq = *(unsigned int *)data;
- enable_percpu_irq(irq, IRQ_TYPE_NONE);
-}
-
-static int
-armpmu_reserve_hardware(struct arm_pmu *armpmu)
-{
- int err, irq;
- unsigned int i, irqs;
- struct platform_device *pmu_device = armpmu->plat_device;
-
- if (!pmu_device)
- return -ENODEV;
-
- irqs = min(pmu_device->num_resources, num_possible_cpus());
- if (!irqs) {
- pr_err("no irqs for PMUs defined\n");
- return -ENODEV;
- }
-
- irq = platform_get_irq(pmu_device, 0);
- if (irq <= 0) {
- pr_err("failed to get valid irq for PMU device\n");
- return -ENODEV;
- }
-
- if (irq_is_percpu(irq)) {
- err = request_percpu_irq(irq, armpmu->handle_irq,
- "arm-pmu", &cpu_hw_events);
-
- if (err) {
- pr_err("unable to request percpu IRQ%d for ARM PMU counters\n",
- irq);
- armpmu_release_hardware(armpmu);
- return err;
- }
-
- on_each_cpu(armpmu_enable_percpu_irq, &irq, 1);
- } else {
- for (i = 0; i < irqs; ++i) {
- int cpu = i;
-
- err = 0;
- irq = platform_get_irq(pmu_device, i);
- if (irq <= 0)
- continue;
-
- if (armpmu->irq_affinity)
- cpu = armpmu->irq_affinity[i];
-
- /*
- * If we have a single PMU interrupt that we can't shift,
- * assume that we're running on a uniprocessor machine and
- * continue. Otherwise, continue without this interrupt.
- */
- if (irq_set_affinity(irq, cpumask_of(cpu)) && irqs > 1) {
- pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n",
- irq, cpu);
- continue;
- }
-
- err = request_irq(irq, armpmu->handle_irq,
- IRQF_NOBALANCING | IRQF_NO_THREAD,
- "arm-pmu", armpmu);
- if (err) {
- pr_err("unable to request IRQ%d for ARM PMU counters\n",
- irq);
- armpmu_release_hardware(armpmu);
- return err;
- }
-
- cpumask_set_cpu(cpu, &armpmu->active_irqs);
- }
- }
-
- return 0;
-}
-
-static void
-hw_perf_event_destroy(struct perf_event *event)
-{
- struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
- atomic_t *active_events = &armpmu->active_events;
- struct mutex *pmu_reserve_mutex = &armpmu->reserve_mutex;
-
- if (atomic_dec_and_mutex_lock(active_events, pmu_reserve_mutex)) {
- armpmu_release_hardware(armpmu);
- mutex_unlock(pmu_reserve_mutex);
- }
-}
-
-static int
-event_requires_mode_exclusion(struct perf_event_attr *attr)
-{
- return attr->exclude_idle || attr->exclude_user ||
- attr->exclude_kernel || attr->exclude_hv;
-}
-
-static int
-__hw_perf_event_init(struct perf_event *event)
-{
- struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
- struct hw_perf_event *hwc = &event->hw;
- int mapping, err;
-
- mapping = armpmu->map_event(event);
-
- if (mapping < 0) {
- pr_debug("event %x:%llx not supported\n", event->attr.type,
- event->attr.config);
- return mapping;
- }
-
- /*
- * We don't assign an index until we actually place the event onto
- * hardware. Use -1 to signify that we haven't decided where to put it
- * yet. For SMP systems, each core has it's own PMU so we can't do any
- * clever allocation or constraints checking at this point.
- */
- hwc->idx = -1;
- hwc->config_base = 0;
- hwc->config = 0;
- hwc->event_base = 0;
-
- /*
- * Check whether we need to exclude the counter from certain modes.
- */
- if ((!armpmu->set_event_filter ||
- armpmu->set_event_filter(hwc, &event->attr)) &&
- event_requires_mode_exclusion(&event->attr)) {
- pr_debug("ARM performance counters do not support mode exclusion\n");
- return -EPERM;
- }
-
- /*
- * Store the event encoding into the config_base field.
- */
- hwc->config_base |= (unsigned long)mapping;
-
- if (!hwc->sample_period) {
- /*
- * For non-sampling runs, limit the sample_period to half
- * of the counter width. That way, the new counter value
- * is far less likely to overtake the previous one unless
- * you have some serious IRQ latency issues.
- */
- hwc->sample_period = armpmu->max_period >> 1;
- hwc->last_period = hwc->sample_period;
- local64_set(&hwc->period_left, hwc->sample_period);
- }
-
- err = 0;
- if (event->group_leader != event) {
- err = validate_group(event);
- if (err)
- return -EINVAL;
- }
-
- return err;
-}
-
-static int armpmu_event_init(struct perf_event *event)
-{
- struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
- int err = 0;
- atomic_t *active_events = &armpmu->active_events;
-
- if (armpmu->map_event(event) == -ENOENT)
- return -ENOENT;
-
- event->destroy = hw_perf_event_destroy;
-
- if (!atomic_inc_not_zero(active_events)) {
- mutex_lock(&armpmu->reserve_mutex);
- if (atomic_read(active_events) == 0)
- err = armpmu_reserve_hardware(armpmu);
-
- if (!err)
- atomic_inc(active_events);
- mutex_unlock(&armpmu->reserve_mutex);
- }
-
- if (err)
- return err;
-
- err = __hw_perf_event_init(event);
- if (err)
- hw_perf_event_destroy(event);
-
- return err;
-}
-
-static void armpmu_enable(struct pmu *pmu)
-{
- struct arm_pmu *armpmu = to_arm_pmu(pmu);
- struct pmu_hw_events *hw_events = armpmu->get_hw_events();
- int enabled = bitmap_weight(hw_events->used_mask, armpmu->num_events);
-
- if (enabled)
- armpmu->start();
-}
-
-static void armpmu_disable(struct pmu *pmu)
-{
- struct arm_pmu *armpmu = to_arm_pmu(pmu);
- armpmu->stop();
-}
-
-static void __init armpmu_init(struct arm_pmu *armpmu)
-{
- atomic_set(&armpmu->active_events, 0);
- mutex_init(&armpmu->reserve_mutex);
-
- armpmu->pmu = (struct pmu) {
- .pmu_enable = armpmu_enable,
- .pmu_disable = armpmu_disable,
- .event_init = armpmu_event_init,
- .add = armpmu_add,
- .del = armpmu_del,
- .start = armpmu_start,
- .stop = armpmu_stop,
- .read = armpmu_read,
- };
-}
-
-int __init armpmu_register(struct arm_pmu *armpmu, char *name, int type)
-{
- armpmu_init(armpmu);
- return perf_pmu_register(&armpmu->pmu, name, type);
-}