diff options
Diffstat (limited to 'arch/mips/kernel/perf_event.c')
-rw-r--r-- | arch/mips/kernel/perf_event.c | 515 |
1 files changed, 1 insertions, 514 deletions
diff --git a/arch/mips/kernel/perf_event.c b/arch/mips/kernel/perf_event.c index f3d6e99ab575..c1cf9c6c3f77 100644 --- a/arch/mips/kernel/perf_event.c +++ b/arch/mips/kernel/perf_event.c @@ -14,529 +14,16 @@ * published by the Free Software Foundation. */ -#include <linux/cpumask.h> -#include <linux/interrupt.h> -#include <linux/smp.h> -#include <linux/kernel.h> #include <linux/perf_event.h> -#include <linux/uaccess.h> -#include <asm/irq.h> -#include <asm/irq_regs.h> #include <asm/stacktrace.h> -#include <asm/time.h> /* For perf_irq */ - -/* These are for 32bit counters. For 64bit ones, define them accordingly. */ -#define MAX_PERIOD ((1ULL << 32) - 1) -#define VALID_COUNT 0x7fffffff -#define TOTAL_BITS 32 -#define HIGHEST_BIT 31 - -#define MIPS_MAX_HWEVENTS 4 - -struct cpu_hw_events { - /* Array of events on this cpu. */ - struct perf_event *events[MIPS_MAX_HWEVENTS]; - - /* - * Set the bit (indexed by the counter number) when the counter - * is used for an event. - */ - unsigned long used_mask[BITS_TO_LONGS(MIPS_MAX_HWEVENTS)]; - - /* - * The borrowed MSB for the performance counter. A MIPS performance - * counter uses its bit 31 (for 32bit counters) or bit 63 (for 64bit - * counters) as a factor of determining whether a counter overflow - * should be signaled. So here we use a separate MSB for each - * counter to make things easy. - */ - unsigned long msbs[BITS_TO_LONGS(MIPS_MAX_HWEVENTS)]; - - /* - * Software copy of the control register for each performance counter. - * MIPS CPUs vary in performance counters. They use this differently, - * and even may not use it. - */ - unsigned int saved_ctrl[MIPS_MAX_HWEVENTS]; -}; -DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = { - .saved_ctrl = {0}, -}; - -/* The description of MIPS performance events. */ -struct mips_perf_event { - unsigned int event_id; - /* - * MIPS performance counters are indexed starting from 0. - * CNTR_EVEN indicates the indexes of the counters to be used are - * even numbers. - */ - unsigned int cntr_mask; - #define CNTR_EVEN 0x55555555 - #define CNTR_ODD 0xaaaaaaaa -#ifdef CONFIG_MIPS_MT_SMP - enum { - T = 0, - V = 1, - P = 2, - } range; -#else - #define T - #define V - #define P -#endif -}; - -static struct mips_perf_event raw_event; -static DEFINE_MUTEX(raw_event_mutex); - -#define UNSUPPORTED_PERF_EVENT_ID 0xffffffff -#define C(x) PERF_COUNT_HW_CACHE_##x - -struct mips_pmu { - const char *name; - int irq; - irqreturn_t (*handle_irq)(int irq, void *dev); - int (*handle_shared_irq)(void); - void (*start)(void); - void (*stop)(void); - int (*alloc_counter)(struct cpu_hw_events *cpuc, - struct hw_perf_event *hwc); - u64 (*read_counter)(unsigned int idx); - void (*write_counter)(unsigned int idx, u64 val); - void (*enable_event)(struct hw_perf_event *evt, int idx); - void (*disable_event)(int idx); - const struct mips_perf_event *(*map_raw_event)(u64 config); - const struct mips_perf_event (*general_event_map)[PERF_COUNT_HW_MAX]; - const struct mips_perf_event (*cache_event_map) - [PERF_COUNT_HW_CACHE_MAX] - [PERF_COUNT_HW_CACHE_OP_MAX] - [PERF_COUNT_HW_CACHE_RESULT_MAX]; - unsigned int num_counters; -}; - -static const struct mips_pmu *mipspmu; - -static int mipspmu_event_set_period(struct perf_event *event, - struct hw_perf_event *hwc, - int idx) -{ - struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); - s64 left = local64_read(&hwc->period_left); - s64 period = hwc->sample_period; - int ret = 0; - u64 uleft; - unsigned long flags; - - 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; - } - - if (left > (s64)MAX_PERIOD) - left = MAX_PERIOD; - - local64_set(&hwc->prev_count, (u64)-left); - - local_irq_save(flags); - uleft = (u64)(-left) & MAX_PERIOD; - uleft > VALID_COUNT ? - set_bit(idx, cpuc->msbs) : clear_bit(idx, cpuc->msbs); - mipspmu->write_counter(idx, (u64)(-left) & VALID_COUNT); - local_irq_restore(flags); - - perf_event_update_userpage(event); - - return ret; -} - -static void mipspmu_event_update(struct perf_event *event, - struct hw_perf_event *hwc, - int idx) -{ - struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); - unsigned long flags; - int shift = 64 - TOTAL_BITS; - s64 prev_raw_count, new_raw_count; - u64 delta; - -again: - prev_raw_count = local64_read(&hwc->prev_count); - local_irq_save(flags); - /* Make the counter value be a "real" one. */ - new_raw_count = mipspmu->read_counter(idx); - if (new_raw_count & (test_bit(idx, cpuc->msbs) << HIGHEST_BIT)) { - new_raw_count &= VALID_COUNT; - clear_bit(idx, cpuc->msbs); - } else - new_raw_count |= (test_bit(idx, cpuc->msbs) << HIGHEST_BIT); - local_irq_restore(flags); - - if (local64_cmpxchg(&hwc->prev_count, prev_raw_count, - new_raw_count) != prev_raw_count) - goto again; - - delta = (new_raw_count << shift) - (prev_raw_count << shift); - delta >>= shift; - - local64_add(delta, &event->count); - local64_sub(delta, &hwc->period_left); -} - -static void mipspmu_start(struct perf_event *event, int flags) -{ - struct hw_perf_event *hwc = &event->hw; - - if (!mipspmu) - return; - - if (flags & PERF_EF_RELOAD) - WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE)); - - hwc->state = 0; - - /* Set the period for the event. */ - mipspmu_event_set_period(event, hwc, hwc->idx); - - /* Enable the event. */ - mipspmu->enable_event(hwc, hwc->idx); -} - -static void mipspmu_stop(struct perf_event *event, int flags) -{ - struct hw_perf_event *hwc = &event->hw; - - if (!mipspmu) - return; - - if (!(hwc->state & PERF_HES_STOPPED)) { - /* We are working on a local event. */ - mipspmu->disable_event(hwc->idx); - barrier(); - mipspmu_event_update(event, hwc, hwc->idx); - hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE; - } -} - -static int mipspmu_add(struct perf_event *event, int flags) -{ - struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); - struct hw_perf_event *hwc = &event->hw; - int idx; - int err = 0; - - perf_pmu_disable(event->pmu); - - /* To look for a free counter for this event. */ - idx = mipspmu->alloc_counter(cpuc, 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; - mipspmu->disable_event(idx); - cpuc->events[idx] = event; - - hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE; - if (flags & PERF_EF_START) - mipspmu_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 void mipspmu_del(struct perf_event *event, int flags) -{ - struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events); - struct hw_perf_event *hwc = &event->hw; - int idx = hwc->idx; - - WARN_ON(idx < 0 || idx >= mipspmu->num_counters); - - mipspmu_stop(event, PERF_EF_UPDATE); - cpuc->events[idx] = NULL; - clear_bit(idx, cpuc->used_mask); - - perf_event_update_userpage(event); -} - -static void mipspmu_read(struct perf_event *event) -{ - struct hw_perf_event *hwc = &event->hw; - - /* Don't read disabled counters! */ - if (hwc->idx < 0) - return; - - mipspmu_event_update(event, hwc, hwc->idx); -} - -static void mipspmu_enable(struct pmu *pmu) -{ - if (mipspmu) - mipspmu->start(); -} - -static void mipspmu_disable(struct pmu *pmu) -{ - if (mipspmu) - mipspmu->stop(); -} - -static atomic_t active_events = ATOMIC_INIT(0); -static DEFINE_MUTEX(pmu_reserve_mutex); -static int (*save_perf_irq)(void); - -static int mipspmu_get_irq(void) -{ - int err; - - if (mipspmu->irq >= 0) { - /* Request my own irq handler. */ - err = request_irq(mipspmu->irq, mipspmu->handle_irq, - IRQF_DISABLED | IRQF_NOBALANCING, - "mips_perf_pmu", NULL); - if (err) { - pr_warning("Unable to request IRQ%d for MIPS " - "performance counters!\n", mipspmu->irq); - } - } else if (cp0_perfcount_irq < 0) { - /* - * We are sharing the irq number with the timer interrupt. - */ - save_perf_irq = perf_irq; - perf_irq = mipspmu->handle_shared_irq; - err = 0; - } else { - pr_warning("The platform hasn't properly defined its " - "interrupt controller.\n"); - err = -ENOENT; - } - - return err; -} - -static void mipspmu_free_irq(void) -{ - if (mipspmu->irq >= 0) - free_irq(mipspmu->irq, NULL); - else if (cp0_perfcount_irq < 0) - perf_irq = save_perf_irq; -} - -/* - * mipsxx/rm9000/loongson2 have different performance counters, they have - * specific low-level init routines. - */ -static void reset_counters(void *arg); -static int __hw_perf_event_init(struct perf_event *event); - -static void hw_perf_event_destroy(struct perf_event *event) -{ - if (atomic_dec_and_mutex_lock(&active_events, - &pmu_reserve_mutex)) { - /* - * We must not call the destroy function with interrupts - * disabled. - */ - on_each_cpu(reset_counters, - (void *)(long)mipspmu->num_counters, 1); - mipspmu_free_irq(); - mutex_unlock(&pmu_reserve_mutex); - } -} - -static int mipspmu_event_init(struct perf_event *event) -{ - int err = 0; - - switch (event->attr.type) { - case PERF_TYPE_RAW: - case PERF_TYPE_HARDWARE: - case PERF_TYPE_HW_CACHE: - break; - - default: - return -ENOENT; - } - - if (!mipspmu || event->cpu >= nr_cpumask_bits || - (event->cpu >= 0 && !cpu_online(event->cpu))) - return -ENODEV; - - if (!atomic_inc_not_zero(&active_events)) { - if (atomic_read(&active_events) > MIPS_MAX_HWEVENTS) { - atomic_dec(&active_events); - return -ENOSPC; - } - - mutex_lock(&pmu_reserve_mutex); - if (atomic_read(&active_events) == 0) - err = mipspmu_get_irq(); - - if (!err) - atomic_inc(&active_events); - mutex_unlock(&pmu_reserve_mutex); - } - - if (err) - return err; - - err = __hw_perf_event_init(event); - if (err) - hw_perf_event_destroy(event); - - return err; -} - -static struct pmu pmu = { - .pmu_enable = mipspmu_enable, - .pmu_disable = mipspmu_disable, - .event_init = mipspmu_event_init, - .add = mipspmu_add, - .del = mipspmu_del, - .start = mipspmu_start, - .stop = mipspmu_stop, - .read = mipspmu_read, -}; - -static unsigned int mipspmu_perf_event_encode(const struct mips_perf_event *pev) -{ -/* - * Top 8 bits for range, next 16 bits for cntr_mask, lowest 8 bits for - * event_id. - */ -#ifdef CONFIG_MIPS_MT_SMP - return ((unsigned int)pev->range << 24) | - (pev->cntr_mask & 0xffff00) | - (pev->event_id & 0xff); -#else - return (pev->cntr_mask & 0xffff00) | - (pev->event_id & 0xff); -#endif -} - -static const struct mips_perf_event *mipspmu_map_general_event(int idx) -{ - const struct mips_perf_event *pev; - - pev = ((*mipspmu->general_event_map)[idx].event_id == - UNSUPPORTED_PERF_EVENT_ID ? ERR_PTR(-EOPNOTSUPP) : - &(*mipspmu->general_event_map)[idx]); - - return pev; -} - -static const struct mips_perf_event *mipspmu_map_cache_event(u64 config) -{ - unsigned int cache_type, cache_op, cache_result; - const struct mips_perf_event *pev; - - cache_type = (config >> 0) & 0xff; - if (cache_type >= PERF_COUNT_HW_CACHE_MAX) - return ERR_PTR(-EINVAL); - - cache_op = (config >> 8) & 0xff; - if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX) - return ERR_PTR(-EINVAL); - - cache_result = (config >> 16) & 0xff; - if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX) - return ERR_PTR(-EINVAL); - - pev = &((*mipspmu->cache_event_map) - [cache_type] - [cache_op] - [cache_result]); - - if (pev->event_id == UNSUPPORTED_PERF_EVENT_ID) - return ERR_PTR(-EOPNOTSUPP); - - return pev; - -} - -static int validate_event(struct cpu_hw_events *cpuc, - struct perf_event *event) -{ - struct hw_perf_event fake_hwc = event->hw; - - /* Allow mixed event group. So return 1 to pass validation. */ - if (event->pmu != &pmu || event->state <= PERF_EVENT_STATE_OFF) - return 1; - - return mipspmu->alloc_counter(cpuc, &fake_hwc) >= 0; -} - -static int validate_group(struct perf_event *event) -{ - struct perf_event *sibling, *leader = event->group_leader; - struct cpu_hw_events fake_cpuc; - - memset(&fake_cpuc, 0, sizeof(fake_cpuc)); - - if (!validate_event(&fake_cpuc, leader)) - return -ENOSPC; - - list_for_each_entry(sibling, &leader->sibling_list, group_entry) { - if (!validate_event(&fake_cpuc, sibling)) - return -ENOSPC; - } - - if (!validate_event(&fake_cpuc, event)) - return -ENOSPC; - - return 0; -} - -/* This is needed by specific irq handlers in perf_event_*.c */ -static void handle_associated_event(struct cpu_hw_events *cpuc, - int idx, struct perf_sample_data *data, - struct pt_regs *regs) -{ - struct perf_event *event = cpuc->events[idx]; - struct hw_perf_event *hwc = &event->hw; - - mipspmu_event_update(event, hwc, idx); - data->period = event->hw.last_period; - if (!mipspmu_event_set_period(event, hwc, idx)) - return; - - if (perf_event_overflow(event, data, regs)) - mipspmu->disable_event(idx); -} - -#include "perf_event_mipsxx.c" /* Callchain handling code. */ /* * Leave userspace callchain empty for now. When we find a way to trace - * the user stack callchains, we add here. + * the user stack callchains, we will add it here. */ -void perf_callchain_user(struct perf_callchain_entry *entry, - struct pt_regs *regs) -{ -} static void save_raw_perf_callchain(struct perf_callchain_entry *entry, unsigned long reg29) |