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-rw-r--r--kernel/arch/arm/kernel/perf_event.c553
1 files changed, 0 insertions, 553 deletions
diff --git a/kernel/arch/arm/kernel/perf_event.c b/kernel/arch/arm/kernel/perf_event.c
deleted file mode 100644
index 4a86a0133..000000000
--- a/kernel/arch/arm/kernel/perf_event.c
+++ /dev/null
@@ -1,553 +0,0 @@
-#undef DEBUG
-
-/*
- * ARM performance counter support.
- *
- * Copyright (C) 2009 picoChip Designs, Ltd., Jamie Iles
- * Copyright (C) 2010 ARM Ltd., Will Deacon <will.deacon@arm.com>
- *
- * This code is based on the sparc64 perf event code, which is in turn based
- * on the x86 code.
- */
-#define pr_fmt(fmt) "hw perfevents: " fmt
-
-#include <linux/kernel.h>
-#include <linux/platform_device.h>
-#include <linux/pm_runtime.h>
-#include <linux/irq.h>
-#include <linux/irqdesc.h>
-
-#include <asm/irq_regs.h>
-#include <asm/pmu.h>
-
-static int
-armpmu_map_cache_event(const unsigned (*cache_map)
- [PERF_COUNT_HW_CACHE_MAX]
- [PERF_COUNT_HW_CACHE_OP_MAX]
- [PERF_COUNT_HW_CACHE_RESULT_MAX],
- u64 config)
-{
- unsigned int cache_type, cache_op, cache_result, ret;
-
- cache_type = (config >> 0) & 0xff;
- if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
- return -EINVAL;
-
- cache_op = (config >> 8) & 0xff;
- if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
- return -EINVAL;
-
- cache_result = (config >> 16) & 0xff;
- if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
- return -EINVAL;
-
- ret = (int)(*cache_map)[cache_type][cache_op][cache_result];
-
- if (ret == CACHE_OP_UNSUPPORTED)
- return -ENOENT;
-
- return ret;
-}
-
-static int
-armpmu_map_hw_event(const unsigned (*event_map)[PERF_COUNT_HW_MAX], u64 config)
-{
- int mapping;
-
- if (config >= PERF_COUNT_HW_MAX)
- return -EINVAL;
-
- mapping = (*event_map)[config];
- return mapping == HW_OP_UNSUPPORTED ? -ENOENT : mapping;
-}
-
-static int
-armpmu_map_raw_event(u32 raw_event_mask, u64 config)
-{
- return (int)(config & raw_event_mask);
-}
-
-int
-armpmu_map_event(struct perf_event *event,
- const unsigned (*event_map)[PERF_COUNT_HW_MAX],
- const unsigned (*cache_map)
- [PERF_COUNT_HW_CACHE_MAX]
- [PERF_COUNT_HW_CACHE_OP_MAX]
- [PERF_COUNT_HW_CACHE_RESULT_MAX],
- u32 raw_event_mask)
-{
- u64 config = event->attr.config;
- int type = event->attr.type;
-
- if (type == event->pmu->type)
- return armpmu_map_raw_event(raw_event_mask, config);
-
- switch (type) {
- case PERF_TYPE_HARDWARE:
- return armpmu_map_hw_event(event_map, config);
- case PERF_TYPE_HW_CACHE:
- return armpmu_map_cache_event(cache_map, config);
- case PERF_TYPE_RAW:
- return armpmu_map_raw_event(raw_event_mask, config);
- }
-
- return -ENOENT;
-}
-
-int armpmu_event_set_period(struct perf_event *event)
-{
- struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
- struct hw_perf_event *hwc = &event->hw;
- s64 left = local64_read(&hwc->period_left);
- s64 period = hwc->sample_period;
- int ret = 0;
-
- if (unlikely(left <= -period)) {
- left = period;
- local64_set(&hwc->period_left, left);
- hwc->last_period = period;
- ret = 1;
- }
-
- if (unlikely(left <= 0)) {
- left += period;
- local64_set(&hwc->period_left, left);
- hwc->last_period = period;
- ret = 1;
- }
-
- /*
- * Limit the maximum period to prevent the counter value
- * from overtaking the one we are about to program. In
- * effect we are reducing max_period to account for
- * interrupt latency (and we are being very conservative).
- */
- if (left > (armpmu->max_period >> 1))
- left = armpmu->max_period >> 1;
-
- local64_set(&hwc->prev_count, (u64)-left);
-
- armpmu->write_counter(event, (u64)(-left) & 0xffffffff);
-
- perf_event_update_userpage(event);
-
- return ret;
-}
-
-u64 armpmu_event_update(struct perf_event *event)
-{
- struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
- struct hw_perf_event *hwc = &event->hw;
- u64 delta, prev_raw_count, new_raw_count;
-
-again:
- prev_raw_count = local64_read(&hwc->prev_count);
- new_raw_count = armpmu->read_counter(event);
-
- if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
- new_raw_count) != prev_raw_count)
- goto again;
-
- delta = (new_raw_count - prev_raw_count) & armpmu->max_period;
-
- local64_add(delta, &event->count);
- local64_sub(delta, &hwc->period_left);
-
- return new_raw_count;
-}
-
-static void
-armpmu_read(struct perf_event *event)
-{
- armpmu_event_update(event);
-}
-
-static void
-armpmu_stop(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 update the counter, so ignore
- * PERF_EF_UPDATE, see comments in armpmu_start().
- */
- if (!(hwc->state & PERF_HES_STOPPED)) {
- armpmu->disable(event);
- armpmu_event_update(event);
- hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
- }
-}
-
-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);
- armpmu->enable(event);
-}
-
-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 = this_cpu_ptr(armpmu->hw_events);
- struct hw_perf_event *hwc = &event->hw;
- int idx = hwc->idx;
-
- armpmu_stop(event, PERF_EF_UPDATE);
- hw_events->events[idx] = NULL;
- clear_bit(idx, hw_events->used_mask);
- if (armpmu->clear_event_idx)
- armpmu->clear_event_idx(hw_events, event);
-
- 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 = this_cpu_ptr(armpmu->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, event);
- 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(event);
- 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;
-
- 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->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, event) >= 0;
-}
-
-static int
-validate_group(struct perf_event *event)
-{
- struct perf_event *sibling, *leader = event->group_leader;
- struct pmu_hw_events fake_pmu;
-
- /*
- * Initialise the fake PMU. We only need to populate the
- * used_mask for the purposes of validation.
- */
- memset(&fake_pmu.used_mask, 0, sizeof(fake_pmu.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 irqreturn_t armpmu_dispatch_irq(int irq, void *dev)
-{
- struct arm_pmu *armpmu;
- struct platform_device *plat_device;
- struct arm_pmu_platdata *plat;
- int ret;
- u64 start_clock, finish_clock;
-
- /*
- * we request the IRQ with a (possibly percpu) struct arm_pmu**, but
- * the handlers expect a struct arm_pmu*. The percpu_irq framework will
- * do any necessary shifting, we just need to perform the first
- * dereference.
- */
- armpmu = *(void **)dev;
- plat_device = armpmu->plat_device;
- plat = dev_get_platdata(&plat_device->dev);
-
- start_clock = sched_clock();
- if (plat && plat->handle_irq)
- ret = plat->handle_irq(irq, armpmu, armpmu->handle_irq);
- else
- ret = armpmu->handle_irq(irq, armpmu);
- finish_clock = sched_clock();
-
- perf_sample_event_took(finish_clock - start_clock);
- return ret;
-}
-
-static void
-armpmu_release_hardware(struct arm_pmu *armpmu)
-{
- armpmu->free_irq(armpmu);
- pm_runtime_put_sync(&armpmu->plat_device->dev);
-}
-
-static int
-armpmu_reserve_hardware(struct arm_pmu *armpmu)
-{
- int err;
- struct platform_device *pmu_device = armpmu->plat_device;
-
- if (!pmu_device)
- return -ENODEV;
-
- pm_runtime_get_sync(&pmu_device->dev);
- err = armpmu->request_irq(armpmu, armpmu_dispatch_irq);
- if (err) {
- armpmu_release_hardware(armpmu);
- return err;
- }
-
- 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;
-
- 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 -EOPNOTSUPP;
- }
-
- /*
- * Store the event encoding into the config_base field.
- */
- hwc->config_base |= (unsigned long)mapping;
-
- if (!is_sampling_event(event)) {
- /*
- * 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);
- }
-
- if (event->group_leader != event) {
- if (validate_group(event) != 0)
- return -EINVAL;
- }
-
- return 0;
-}
-
-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;
-
- /* does not support taken branch sampling */
- if (has_branch_stack(event))
- return -EOPNOTSUPP;
-
- 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 = this_cpu_ptr(armpmu->hw_events);
- int enabled = bitmap_weight(hw_events->used_mask, armpmu->num_events);
-
- if (enabled)
- armpmu->start(armpmu);
-}
-
-static void armpmu_disable(struct pmu *pmu)
-{
- struct arm_pmu *armpmu = to_arm_pmu(pmu);
- armpmu->stop(armpmu);
-}
-
-#ifdef CONFIG_PM
-static int armpmu_runtime_resume(struct device *dev)
-{
- struct arm_pmu_platdata *plat = dev_get_platdata(dev);
-
- if (plat && plat->runtime_resume)
- return plat->runtime_resume(dev);
-
- return 0;
-}
-
-static int armpmu_runtime_suspend(struct device *dev)
-{
- struct arm_pmu_platdata *plat = dev_get_platdata(dev);
-
- if (plat && plat->runtime_suspend)
- return plat->runtime_suspend(dev);
-
- return 0;
-}
-#endif
-
-const struct dev_pm_ops armpmu_dev_pm_ops = {
- SET_RUNTIME_PM_OPS(armpmu_runtime_suspend, armpmu_runtime_resume, NULL)
-};
-
-static void 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 armpmu_register(struct arm_pmu *armpmu, int type)
-{
- armpmu_init(armpmu);
- pm_runtime_enable(&armpmu->plat_device->dev);
- pr_info("enabled with %s PMU driver, %d counters available\n",
- armpmu->name, armpmu->num_events);
- return perf_pmu_register(&armpmu->pmu, armpmu->name, type);
-}
-