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-rw-r--r--arch/mips/kernel/perf_event.c521
1 files changed, 1 insertions, 520 deletions
diff --git a/arch/mips/kernel/perf_event.c b/arch/mips/kernel/perf_event.c
index a824485..c1cf9c6 100644
--- a/arch/mips/kernel/perf_event.c
+++ b/arch/mips/kernel/perf_event.c
@@ -14,535 +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);
-
- return;
-}
-
-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 inline 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, 0, 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)
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