#include <linux/kernel_stat.h>
#include <linux/perf_event.h>
#include <linux/ftrace_event.h>
-#include <linux/hw_breakpoint.h>
#include <asm/irq_regs.h>
*/
static DEFINE_SPINLOCK(perf_resource_lock);
-/*
- * Architecture provided APIs - weak aliases:
- */
-extern __weak const struct pmu *hw_perf_event_init(struct perf_event *event)
-{
- return NULL;
-}
-
void __weak hw_perf_disable(void) { barrier(); }
void __weak hw_perf_enable(void) { barrier(); }
struct perf_event_context *ctx;
rcu_read_lock();
- retry:
+retry:
ctx = rcu_dereference(task->perf_event_ctxp);
if (ctx) {
/*
}
}
+static inline int
+event_filter_match(struct perf_event *event)
+{
+ return event->cpu == -1 || event->cpu == smp_processor_id();
+}
+
static void
event_sched_out(struct perf_event *event,
struct perf_cpu_context *cpuctx,
struct perf_event_context *ctx)
{
+ u64 delta;
+ /*
+ * An event which could not be activated because of
+ * filter mismatch still needs to have its timings
+ * maintained, otherwise bogus information is return
+ * via read() for time_enabled, time_running:
+ */
+ if (event->state == PERF_EVENT_STATE_INACTIVE
+ && !event_filter_match(event)) {
+ delta = ctx->time - event->tstamp_stopped;
+ event->tstamp_running += delta;
+ event->tstamp_stopped = ctx->time;
+ }
+
if (event->state != PERF_EVENT_STATE_ACTIVE)
return;
struct perf_event_context *ctx)
{
struct perf_event *event;
-
- if (group_event->state != PERF_EVENT_STATE_ACTIVE)
- return;
+ int state = group_event->state;
event_sched_out(group_event, cpuctx, ctx);
list_for_each_entry(event, &group_event->sibling_list, group_entry)
event_sched_out(event, cpuctx, ctx);
- if (group_event->attr.exclusive)
+ if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive)
cpuctx->exclusive = 0;
}
return;
raw_spin_lock(&ctx->lock);
- /*
- * Protect the list operation against NMI by disabling the
- * events on a global level.
- */
- perf_disable();
event_sched_out(event, cpuctx, ctx);
perf_max_events - perf_reserved_percpu);
}
- perf_enable();
raw_spin_unlock(&ctx->lock);
}
return;
}
- retry:
+retry:
task_oncpu_function_call(task, __perf_event_disable, event);
raw_spin_lock_irq(&ctx->lock);
struct perf_event_context *ctx)
{
struct perf_event *event, *partial_group = NULL;
- const struct pmu *pmu = group_event->pmu;
+ struct pmu *pmu = group_event->pmu;
bool txn = false;
if (group_event->state == PERF_EVENT_STATE_OFF)
ctx->is_active = 1;
update_context_time(ctx);
- /*
- * Protect the list operation against NMI by disabling the
- * events on a global level. NOP for non NMI based events.
- */
- perf_disable();
-
add_event_to_ctx(event, ctx);
if (event->cpu != -1 && event->cpu != smp_processor_id())
if (!err && !ctx->task && cpuctx->max_pertask)
cpuctx->max_pertask--;
- unlock:
- perf_enable();
-
+unlock:
raw_spin_unlock(&ctx->lock);
}
event->state = PERF_EVENT_STATE_INACTIVE;
event->tstamp_enabled = ctx->time - event->total_time_enabled;
- list_for_each_entry(sub, &event->sibling_list, group_entry)
- if (sub->state >= PERF_EVENT_STATE_INACTIVE)
+ list_for_each_entry(sub, &event->sibling_list, group_entry) {
+ if (sub->state >= PERF_EVENT_STATE_INACTIVE) {
sub->tstamp_enabled =
ctx->time - sub->total_time_enabled;
+ }
+ }
}
/*
if (!group_can_go_on(event, cpuctx, 1)) {
err = -EEXIST;
} else {
- perf_disable();
if (event == leader)
err = group_sched_in(event, cpuctx, ctx);
else
err = event_sched_in(event, cpuctx, ctx);
- perf_enable();
}
if (err) {
}
}
- unlock:
+unlock:
raw_spin_unlock(&ctx->lock);
}
if (event->state == PERF_EVENT_STATE_ERROR)
event->state = PERF_EVENT_STATE_OFF;
- retry:
+retry:
raw_spin_unlock_irq(&ctx->lock);
task_oncpu_function_call(task, __perf_event_enable, event);
if (event->state == PERF_EVENT_STATE_OFF)
__perf_event_mark_enabled(event, ctx);
- out:
+out:
raw_spin_unlock_irq(&ctx->lock);
}
goto out;
update_context_time(ctx);
- perf_disable();
if (!ctx->nr_active)
- goto out_enable;
+ goto out;
- if (event_type & EVENT_PINNED)
+ if (event_type & EVENT_PINNED) {
list_for_each_entry(event, &ctx->pinned_groups, group_entry)
group_sched_out(event, cpuctx, ctx);
+ }
- if (event_type & EVENT_FLEXIBLE)
+ if (event_type & EVENT_FLEXIBLE) {
list_for_each_entry(event, &ctx->flexible_groups, group_entry)
group_sched_out(event, cpuctx, ctx);
-
- out_enable:
- perf_enable();
- out:
+ }
+out:
raw_spin_unlock(&ctx->lock);
}
if (event->cpu != -1 && event->cpu != smp_processor_id())
continue;
- if (group_can_go_on(event, cpuctx, can_add_hw))
+ if (group_can_go_on(event, cpuctx, can_add_hw)) {
if (group_sched_in(event, cpuctx, ctx))
can_add_hw = 0;
+ }
}
}
ctx->timestamp = perf_clock();
- perf_disable();
-
/*
* First go through the list and put on any pinned groups
* in order to give them the best chance of going on.
if (event_type & EVENT_FLEXIBLE)
ctx_flexible_sched_in(ctx, cpuctx);
- perf_enable();
- out:
+out:
raw_spin_unlock(&ctx->lock);
}
if (cpuctx->task_ctx == ctx)
return;
- perf_disable();
-
/*
* We want to keep the following priority order:
* cpu pinned (that don't need to move), task pinned,
ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE);
cpuctx->task_ctx = ctx;
-
- perf_enable();
}
#define MAX_INTERRUPTS (~0ULL)
hwc->sample_period = sample_period;
if (local64_read(&hwc->period_left) > 8*sample_period) {
- perf_disable();
perf_event_stop(event);
local64_set(&hwc->period_left, 0);
perf_event_start(event);
- perf_enable();
}
}
*/
if (interrupts == MAX_INTERRUPTS) {
perf_log_throttle(event, 1);
- perf_disable();
event->pmu->unthrottle(event);
- perf_enable();
}
if (!event->attr.freq || !event->attr.sample_freq)
continue;
- perf_disable();
event->pmu->read(event);
now = local64_read(&event->count);
delta = now - hwc->freq_count_stamp;
if (delta > 0)
perf_adjust_period(event, TICK_NSEC, delta);
- perf_enable();
}
raw_spin_unlock(&ctx->lock);
}
if (!rotate)
return;
- perf_disable();
cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
if (ctx)
task_ctx_sched_out(ctx, EVENT_FLEXIBLE);
cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE);
if (ctx)
task_ctx_sched_in(curr, EVENT_FLEXIBLE);
- perf_enable();
}
static int event_enable_on_exec(struct perf_event *event,
raw_spin_unlock(&ctx->lock);
perf_event_task_sched_in(task);
- out:
+out:
local_irq_restore(flags);
}
return perf_event_count(event);
}
+/*
+ * Callchain support
+ */
+
+struct callchain_cpus_entries {
+ struct rcu_head rcu_head;
+ struct perf_callchain_entry *cpu_entries[0];
+};
+
+static DEFINE_PER_CPU(int, callchain_recursion[PERF_NR_CONTEXTS]);
+static atomic_t nr_callchain_events;
+static DEFINE_MUTEX(callchain_mutex);
+struct callchain_cpus_entries *callchain_cpus_entries;
+
+
+__weak void perf_callchain_kernel(struct perf_callchain_entry *entry,
+ struct pt_regs *regs)
+{
+}
+
+__weak void perf_callchain_user(struct perf_callchain_entry *entry,
+ struct pt_regs *regs)
+{
+}
+
+static void release_callchain_buffers_rcu(struct rcu_head *head)
+{
+ struct callchain_cpus_entries *entries;
+ int cpu;
+
+ entries = container_of(head, struct callchain_cpus_entries, rcu_head);
+
+ for_each_possible_cpu(cpu)
+ kfree(entries->cpu_entries[cpu]);
+
+ kfree(entries);
+}
+
+static void release_callchain_buffers(void)
+{
+ struct callchain_cpus_entries *entries;
+
+ entries = callchain_cpus_entries;
+ rcu_assign_pointer(callchain_cpus_entries, NULL);
+ call_rcu(&entries->rcu_head, release_callchain_buffers_rcu);
+}
+
+static int alloc_callchain_buffers(void)
+{
+ int cpu;
+ int size;
+ struct callchain_cpus_entries *entries;
+
+ /*
+ * We can't use the percpu allocation API for data that can be
+ * accessed from NMI. Use a temporary manual per cpu allocation
+ * until that gets sorted out.
+ */
+ size = sizeof(*entries) + sizeof(struct perf_callchain_entry *) *
+ num_possible_cpus();
+
+ entries = kzalloc(size, GFP_KERNEL);
+ if (!entries)
+ return -ENOMEM;
+
+ size = sizeof(struct perf_callchain_entry) * PERF_NR_CONTEXTS;
+
+ for_each_possible_cpu(cpu) {
+ entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL,
+ cpu_to_node(cpu));
+ if (!entries->cpu_entries[cpu])
+ goto fail;
+ }
+
+ rcu_assign_pointer(callchain_cpus_entries, entries);
+
+ return 0;
+
+fail:
+ for_each_possible_cpu(cpu)
+ kfree(entries->cpu_entries[cpu]);
+ kfree(entries);
+
+ return -ENOMEM;
+}
+
+static int get_callchain_buffers(void)
+{
+ int err = 0;
+ int count;
+
+ mutex_lock(&callchain_mutex);
+
+ count = atomic_inc_return(&nr_callchain_events);
+ if (WARN_ON_ONCE(count < 1)) {
+ err = -EINVAL;
+ goto exit;
+ }
+
+ if (count > 1) {
+ /* If the allocation failed, give up */
+ if (!callchain_cpus_entries)
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ err = alloc_callchain_buffers();
+ if (err)
+ release_callchain_buffers();
+exit:
+ mutex_unlock(&callchain_mutex);
+
+ return err;
+}
+
+static void put_callchain_buffers(void)
+{
+ if (atomic_dec_and_mutex_lock(&nr_callchain_events, &callchain_mutex)) {
+ release_callchain_buffers();
+ mutex_unlock(&callchain_mutex);
+ }
+}
+
+static int get_recursion_context(int *recursion)
+{
+ int rctx;
+
+ if (in_nmi())
+ rctx = 3;
+ else if (in_irq())
+ rctx = 2;
+ else if (in_softirq())
+ rctx = 1;
+ else
+ rctx = 0;
+
+ if (recursion[rctx])
+ return -1;
+
+ recursion[rctx]++;
+ barrier();
+
+ return rctx;
+}
+
+static inline void put_recursion_context(int *recursion, int rctx)
+{
+ barrier();
+ recursion[rctx]--;
+}
+
+static struct perf_callchain_entry *get_callchain_entry(int *rctx)
+{
+ int cpu;
+ struct callchain_cpus_entries *entries;
+
+ *rctx = get_recursion_context(__get_cpu_var(callchain_recursion));
+ if (*rctx == -1)
+ return NULL;
+
+ entries = rcu_dereference(callchain_cpus_entries);
+ if (!entries)
+ return NULL;
+
+ cpu = smp_processor_id();
+
+ return &entries->cpu_entries[cpu][*rctx];
+}
+
+static void
+put_callchain_entry(int rctx)
+{
+ put_recursion_context(__get_cpu_var(callchain_recursion), rctx);
+}
+
+static struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
+{
+ int rctx;
+ struct perf_callchain_entry *entry;
+
+
+ entry = get_callchain_entry(&rctx);
+ if (rctx == -1)
+ return NULL;
+
+ if (!entry)
+ goto exit_put;
+
+ entry->nr = 0;
+
+ if (!user_mode(regs)) {
+ perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
+ perf_callchain_kernel(entry, regs);
+ if (current->mm)
+ regs = task_pt_regs(current);
+ else
+ regs = NULL;
+ }
+
+ if (regs) {
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_user(entry, regs);
+ }
+
+exit_put:
+ put_callchain_entry(rctx);
+
+ return entry;
+}
+
/*
* Initialize the perf_event context in a task_struct:
*/
if (!ptrace_may_access(task, PTRACE_MODE_READ))
goto errout;
- retry:
+retry:
ctx = perf_lock_task_context(task, &flags);
if (ctx) {
unclone_ctx(ctx);
put_task_struct(task);
return ctx;
- errout:
+errout:
put_task_struct(task);
return ERR_PTR(err);
}
atomic_dec(&nr_comm_events);
if (event->attr.task)
atomic_dec(&nr_task_events);
+ if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN)
+ put_callchain_buffers();
}
if (event->buffer) {
__perf_pending_run();
}
-/*
- * Callchain support -- arch specific
- */
-
-__weak struct perf_callchain_entry *perf_callchain(struct pt_regs *regs)
-{
- return NULL;
-}
-
-
/*
* We assume there is only KVM supporting the callbacks.
* Later on, we might change it to a list if there is
if (handle->wakeup != local_read(&buffer->wakeup))
perf_output_wakeup(handle);
- out:
+out:
preempt_enable();
}
struct perf_output_handle handle;
struct perf_event_header header;
+ /* protect the callchain buffers */
+ rcu_read_lock();
+
perf_prepare_sample(&header, data, event, regs);
if (perf_output_begin(&handle, event, header.size, nmi, 1))
- return;
+ goto exit;
perf_output_sample(&handle, &header, data, event);
perf_output_end(&handle);
+
+exit:
+ rcu_read_unlock();
}
/*
int perf_swevent_get_recursion_context(void)
{
struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
- int rctx;
-
- if (in_nmi())
- rctx = 3;
- else if (in_irq())
- rctx = 2;
- else if (in_softirq())
- rctx = 1;
- else
- rctx = 0;
-
- if (cpuctx->recursion[rctx])
- return -1;
- cpuctx->recursion[rctx]++;
- barrier();
-
- return rctx;
+ return get_recursion_context(cpuctx->recursion);
}
EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context);
void inline perf_swevent_put_recursion_context(int rctx)
{
struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
- barrier();
- cpuctx->recursion[rctx]--;
+
+ put_recursion_context(cpuctx->recursion, rctx);
}
void __perf_sw_event(u32 event_id, u64 nr, int nmi,
return 0;
}
-static const struct pmu perf_ops_generic = {
- .enable = perf_swevent_enable,
- .disable = perf_swevent_disable,
- .start = perf_swevent_int,
- .stop = perf_swevent_void,
- .read = perf_swevent_read,
- .unthrottle = perf_swevent_void, /* hwc->interrupts already reset */
-};
+/* Deref the hlist from the update side */
+static inline struct swevent_hlist *
+swevent_hlist_deref(struct perf_cpu_context *cpuctx)
+{
+ return rcu_dereference_protected(cpuctx->swevent_hlist,
+ lockdep_is_held(&cpuctx->hlist_mutex));
+}
-/*
- * hrtimer based swevent callback
- */
+static void swevent_hlist_release_rcu(struct rcu_head *rcu_head)
+{
+ struct swevent_hlist *hlist;
-static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
+ hlist = container_of(rcu_head, struct swevent_hlist, rcu_head);
+ kfree(hlist);
+}
+
+static void swevent_hlist_release(struct perf_cpu_context *cpuctx)
{
- enum hrtimer_restart ret = HRTIMER_RESTART;
- struct perf_sample_data data;
- struct pt_regs *regs;
- struct perf_event *event;
- u64 period;
+ struct swevent_hlist *hlist = swevent_hlist_deref(cpuctx);
- event = container_of(hrtimer, struct perf_event, hw.hrtimer);
- event->pmu->read(event);
+ if (!hlist)
+ return;
- perf_sample_data_init(&data, 0);
- data.period = event->hw.last_period;
- regs = get_irq_regs();
+ rcu_assign_pointer(cpuctx->swevent_hlist, NULL);
+ call_rcu(&hlist->rcu_head, swevent_hlist_release_rcu);
+}
- if (regs && !perf_exclude_event(event, regs)) {
- if (!(event->attr.exclude_idle && current->pid == 0))
- if (perf_event_overflow(event, 0, &data, regs))
- ret = HRTIMER_NORESTART;
- }
+static void swevent_hlist_put_cpu(struct perf_event *event, int cpu)
+{
+ struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
- period = max_t(u64, 10000, event->hw.sample_period);
- hrtimer_forward_now(hrtimer, ns_to_ktime(period));
+ mutex_lock(&cpuctx->hlist_mutex);
- return ret;
+ if (!--cpuctx->hlist_refcount)
+ swevent_hlist_release(cpuctx);
+
+ mutex_unlock(&cpuctx->hlist_mutex);
}
-static void perf_swevent_start_hrtimer(struct perf_event *event)
+static void swevent_hlist_put(struct perf_event *event)
{
- struct hw_perf_event *hwc = &event->hw;
-
- hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- hwc->hrtimer.function = perf_swevent_hrtimer;
- if (hwc->sample_period) {
- u64 period;
-
- if (hwc->remaining) {
- if (hwc->remaining < 0)
- period = 10000;
- else
- period = hwc->remaining;
- hwc->remaining = 0;
- } else {
- period = max_t(u64, 10000, hwc->sample_period);
- }
- __hrtimer_start_range_ns(&hwc->hrtimer,
- ns_to_ktime(period), 0,
- HRTIMER_MODE_REL, 0);
- }
-}
-
-static void perf_swevent_cancel_hrtimer(struct perf_event *event)
-{
- struct hw_perf_event *hwc = &event->hw;
-
- if (hwc->sample_period) {
- ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer);
- hwc->remaining = ktime_to_ns(remaining);
-
- hrtimer_cancel(&hwc->hrtimer);
- }
-}
-
-/*
- * Software event: cpu wall time clock
- */
-
-static void cpu_clock_perf_event_update(struct perf_event *event)
-{
- int cpu = raw_smp_processor_id();
- s64 prev;
- u64 now;
-
- now = cpu_clock(cpu);
- prev = local64_xchg(&event->hw.prev_count, now);
- local64_add(now - prev, &event->count);
-}
-
-static int cpu_clock_perf_event_enable(struct perf_event *event)
-{
- struct hw_perf_event *hwc = &event->hw;
- int cpu = raw_smp_processor_id();
-
- local64_set(&hwc->prev_count, cpu_clock(cpu));
- perf_swevent_start_hrtimer(event);
-
- return 0;
-}
-
-static void cpu_clock_perf_event_disable(struct perf_event *event)
-{
- perf_swevent_cancel_hrtimer(event);
- cpu_clock_perf_event_update(event);
-}
-
-static void cpu_clock_perf_event_read(struct perf_event *event)
-{
- cpu_clock_perf_event_update(event);
-}
-
-static const struct pmu perf_ops_cpu_clock = {
- .enable = cpu_clock_perf_event_enable,
- .disable = cpu_clock_perf_event_disable,
- .read = cpu_clock_perf_event_read,
-};
-
-/*
- * Software event: task time clock
- */
-
-static void task_clock_perf_event_update(struct perf_event *event, u64 now)
-{
- u64 prev;
- s64 delta;
-
- prev = local64_xchg(&event->hw.prev_count, now);
- delta = now - prev;
- local64_add(delta, &event->count);
-}
-
-static int task_clock_perf_event_enable(struct perf_event *event)
-{
- struct hw_perf_event *hwc = &event->hw;
- u64 now;
-
- now = event->ctx->time;
-
- local64_set(&hwc->prev_count, now);
-
- perf_swevent_start_hrtimer(event);
-
- return 0;
-}
-
-static void task_clock_perf_event_disable(struct perf_event *event)
-{
- perf_swevent_cancel_hrtimer(event);
- task_clock_perf_event_update(event, event->ctx->time);
-
-}
-
-static void task_clock_perf_event_read(struct perf_event *event)
-{
- u64 time;
-
- if (!in_nmi()) {
- update_context_time(event->ctx);
- time = event->ctx->time;
- } else {
- u64 now = perf_clock();
- u64 delta = now - event->ctx->timestamp;
- time = event->ctx->time + delta;
- }
-
- task_clock_perf_event_update(event, time);
-}
-
-static const struct pmu perf_ops_task_clock = {
- .enable = task_clock_perf_event_enable,
- .disable = task_clock_perf_event_disable,
- .read = task_clock_perf_event_read,
-};
-
-/* Deref the hlist from the update side */
-static inline struct swevent_hlist *
-swevent_hlist_deref(struct perf_cpu_context *cpuctx)
-{
- return rcu_dereference_protected(cpuctx->swevent_hlist,
- lockdep_is_held(&cpuctx->hlist_mutex));
-}
-
-static void swevent_hlist_release_rcu(struct rcu_head *rcu_head)
-{
- struct swevent_hlist *hlist;
-
- hlist = container_of(rcu_head, struct swevent_hlist, rcu_head);
- kfree(hlist);
-}
-
-static void swevent_hlist_release(struct perf_cpu_context *cpuctx)
-{
- struct swevent_hlist *hlist = swevent_hlist_deref(cpuctx);
-
- if (!hlist)
- return;
-
- rcu_assign_pointer(cpuctx->swevent_hlist, NULL);
- call_rcu(&hlist->rcu_head, swevent_hlist_release_rcu);
-}
-
-static void swevent_hlist_put_cpu(struct perf_event *event, int cpu)
-{
- struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
-
- mutex_lock(&cpuctx->hlist_mutex);
-
- if (!--cpuctx->hlist_refcount)
- swevent_hlist_release(cpuctx);
-
- mutex_unlock(&cpuctx->hlist_mutex);
-}
-
-static void swevent_hlist_put(struct perf_event *event)
-{
- int cpu;
+ int cpu;
if (event->cpu != -1) {
swevent_hlist_put_cpu(event, event->cpu);
rcu_assign_pointer(cpuctx->swevent_hlist, hlist);
}
cpuctx->hlist_refcount++;
- exit:
+exit:
mutex_unlock(&cpuctx->hlist_mutex);
return err;
put_online_cpus();
return 0;
- fail:
+fail:
for_each_possible_cpu(cpu) {
if (cpu == failed_cpu)
break;
return err;
}
-#ifdef CONFIG_EVENT_TRACING
+atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
-static const struct pmu perf_ops_tracepoint = {
- .enable = perf_trace_enable,
- .disable = perf_trace_disable,
+static void sw_perf_event_destroy(struct perf_event *event)
+{
+ u64 event_id = event->attr.config;
+
+ WARN_ON(event->parent);
+
+ atomic_dec(&perf_swevent_enabled[event_id]);
+ swevent_hlist_put(event);
+}
+
+static int perf_swevent_init(struct perf_event *event)
+{
+ int event_id = event->attr.config;
+
+ if (event->attr.type != PERF_TYPE_SOFTWARE)
+ return -ENOENT;
+
+ switch (event_id) {
+ case PERF_COUNT_SW_CPU_CLOCK:
+ case PERF_COUNT_SW_TASK_CLOCK:
+ return -ENOENT;
+
+ default:
+ break;
+ }
+
+ if (event_id > PERF_COUNT_SW_MAX)
+ return -ENOENT;
+
+ if (!event->parent) {
+ int err;
+
+ err = swevent_hlist_get(event);
+ if (err)
+ return err;
+
+ atomic_inc(&perf_swevent_enabled[event_id]);
+ event->destroy = sw_perf_event_destroy;
+ }
+
+ return 0;
+}
+
+static struct pmu perf_swevent = {
+ .event_init = perf_swevent_init,
+ .enable = perf_swevent_enable,
+ .disable = perf_swevent_disable,
.start = perf_swevent_int,
.stop = perf_swevent_void,
.read = perf_swevent_read,
- .unthrottle = perf_swevent_void,
+ .unthrottle = perf_swevent_void, /* hwc->interrupts already reset */
};
+#ifdef CONFIG_EVENT_TRACING
+
static int perf_tp_filter_match(struct perf_event *event,
struct perf_sample_data *data)
{
perf_trace_destroy(event);
}
-static const struct pmu *tp_perf_event_init(struct perf_event *event)
+static int perf_tp_event_init(struct perf_event *event)
{
int err;
+ if (event->attr.type != PERF_TYPE_TRACEPOINT)
+ return -ENOENT;
+
/*
* Raw tracepoint data is a severe data leak, only allow root to
* have these.
if ((event->attr.sample_type & PERF_SAMPLE_RAW) &&
perf_paranoid_tracepoint_raw() &&
!capable(CAP_SYS_ADMIN))
- return ERR_PTR(-EPERM);
+ return -EPERM;
err = perf_trace_init(event);
if (err)
- return NULL;
+ return err;
event->destroy = tp_perf_event_destroy;
- return &perf_ops_tracepoint;
+ return 0;
+}
+
+static struct pmu perf_tracepoint = {
+ .event_init = perf_tp_event_init,
+ .enable = perf_trace_enable,
+ .disable = perf_trace_disable,
+ .start = perf_swevent_int,
+ .stop = perf_swevent_void,
+ .read = perf_swevent_read,
+ .unthrottle = perf_swevent_void,
+};
+
+static inline void perf_tp_register(void)
+{
+ perf_pmu_register(&perf_tracepoint);
}
static int perf_event_set_filter(struct perf_event *event, void __user *arg)
#else
-static const struct pmu *tp_perf_event_init(struct perf_event *event)
+static inline void perf_tp_register(void)
{
- return NULL;
}
static int perf_event_set_filter(struct perf_event *event, void __user *arg)
#endif /* CONFIG_EVENT_TRACING */
#ifdef CONFIG_HAVE_HW_BREAKPOINT
-static void bp_perf_event_destroy(struct perf_event *event)
+void perf_bp_event(struct perf_event *bp, void *data)
{
- release_bp_slot(event);
+ struct perf_sample_data sample;
+ struct pt_regs *regs = data;
+
+ perf_sample_data_init(&sample, bp->attr.bp_addr);
+
+ if (!perf_exclude_event(bp, regs))
+ perf_swevent_add(bp, 1, 1, &sample, regs);
}
+#endif
-static const struct pmu *bp_perf_event_init(struct perf_event *bp)
+/*
+ * hrtimer based swevent callback
+ */
+
+static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
{
- int err;
+ enum hrtimer_restart ret = HRTIMER_RESTART;
+ struct perf_sample_data data;
+ struct pt_regs *regs;
+ struct perf_event *event;
+ u64 period;
- err = register_perf_hw_breakpoint(bp);
- if (err)
- return ERR_PTR(err);
+ event = container_of(hrtimer, struct perf_event, hw.hrtimer);
+ event->pmu->read(event);
- bp->destroy = bp_perf_event_destroy;
+ perf_sample_data_init(&data, 0);
+ data.period = event->hw.last_period;
+ regs = get_irq_regs();
+
+ if (regs && !perf_exclude_event(event, regs)) {
+ if (!(event->attr.exclude_idle && current->pid == 0))
+ if (perf_event_overflow(event, 0, &data, regs))
+ ret = HRTIMER_NORESTART;
+ }
+
+ period = max_t(u64, 10000, event->hw.sample_period);
+ hrtimer_forward_now(hrtimer, ns_to_ktime(period));
- return &perf_ops_bp;
+ return ret;
}
-void perf_bp_event(struct perf_event *bp, void *data)
+static void perf_swevent_start_hrtimer(struct perf_event *event)
{
- struct perf_sample_data sample;
- struct pt_regs *regs = data;
+ struct hw_perf_event *hwc = &event->hw;
- perf_sample_data_init(&sample, bp->attr.bp_addr);
+ hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hwc->hrtimer.function = perf_swevent_hrtimer;
+ if (hwc->sample_period) {
+ u64 period;
- if (!perf_exclude_event(bp, regs))
- perf_swevent_add(bp, 1, 1, &sample, regs);
+ if (hwc->remaining) {
+ if (hwc->remaining < 0)
+ period = 10000;
+ else
+ period = hwc->remaining;
+ hwc->remaining = 0;
+ } else {
+ period = max_t(u64, 10000, hwc->sample_period);
+ }
+ __hrtimer_start_range_ns(&hwc->hrtimer,
+ ns_to_ktime(period), 0,
+ HRTIMER_MODE_REL, 0);
+ }
}
-#else
-static const struct pmu *bp_perf_event_init(struct perf_event *bp)
+
+static void perf_swevent_cancel_hrtimer(struct perf_event *event)
{
- return NULL;
+ struct hw_perf_event *hwc = &event->hw;
+
+ if (hwc->sample_period) {
+ ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer);
+ hwc->remaining = ktime_to_ns(remaining);
+
+ hrtimer_cancel(&hwc->hrtimer);
+ }
}
-void perf_bp_event(struct perf_event *bp, void *regs)
+/*
+ * Software event: cpu wall time clock
+ */
+
+static void cpu_clock_event_update(struct perf_event *event)
{
+ int cpu = raw_smp_processor_id();
+ s64 prev;
+ u64 now;
+
+ now = cpu_clock(cpu);
+ prev = local64_xchg(&event->hw.prev_count, now);
+ local64_add(now - prev, &event->count);
}
-#endif
-atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
+static int cpu_clock_event_enable(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int cpu = raw_smp_processor_id();
-static void sw_perf_event_destroy(struct perf_event *event)
+ local64_set(&hwc->prev_count, cpu_clock(cpu));
+ perf_swevent_start_hrtimer(event);
+
+ return 0;
+}
+
+static void cpu_clock_event_disable(struct perf_event *event)
{
- u64 event_id = event->attr.config;
+ perf_swevent_cancel_hrtimer(event);
+ cpu_clock_event_update(event);
+}
- WARN_ON(event->parent);
+static void cpu_clock_event_read(struct perf_event *event)
+{
+ cpu_clock_event_update(event);
+}
- atomic_dec(&perf_swevent_enabled[event_id]);
- swevent_hlist_put(event);
+static int cpu_clock_event_init(struct perf_event *event)
+{
+ if (event->attr.type != PERF_TYPE_SOFTWARE)
+ return -ENOENT;
+
+ if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK)
+ return -ENOENT;
+
+ return 0;
}
-static const struct pmu *sw_perf_event_init(struct perf_event *event)
+static struct pmu perf_cpu_clock = {
+ .event_init = cpu_clock_event_init,
+ .enable = cpu_clock_event_enable,
+ .disable = cpu_clock_event_disable,
+ .read = cpu_clock_event_read,
+};
+
+/*
+ * Software event: task time clock
+ */
+
+static void task_clock_event_update(struct perf_event *event, u64 now)
{
- const struct pmu *pmu = NULL;
- u64 event_id = event->attr.config;
+ u64 prev;
+ s64 delta;
- /*
- * Software events (currently) can't in general distinguish
- * between user, kernel and hypervisor events.
- * However, context switches and cpu migrations are considered
- * to be kernel events, and page faults are never hypervisor
- * events.
- */
- switch (event_id) {
- case PERF_COUNT_SW_CPU_CLOCK:
- pmu = &perf_ops_cpu_clock;
+ prev = local64_xchg(&event->hw.prev_count, now);
+ delta = now - prev;
+ local64_add(delta, &event->count);
+}
- break;
- case PERF_COUNT_SW_TASK_CLOCK:
- /*
- * If the user instantiates this as a per-cpu event,
- * use the cpu_clock event instead.
- */
- if (event->ctx->task)
- pmu = &perf_ops_task_clock;
- else
- pmu = &perf_ops_cpu_clock;
+static int task_clock_event_enable(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ u64 now;
- break;
- case PERF_COUNT_SW_PAGE_FAULTS:
- case PERF_COUNT_SW_PAGE_FAULTS_MIN:
- case PERF_COUNT_SW_PAGE_FAULTS_MAJ:
- case PERF_COUNT_SW_CONTEXT_SWITCHES:
- case PERF_COUNT_SW_CPU_MIGRATIONS:
- case PERF_COUNT_SW_ALIGNMENT_FAULTS:
- case PERF_COUNT_SW_EMULATION_FAULTS:
- if (!event->parent) {
- int err;
-
- err = swevent_hlist_get(event);
- if (err)
- return ERR_PTR(err);
+ now = event->ctx->time;
+
+ local64_set(&hwc->prev_count, now);
+
+ perf_swevent_start_hrtimer(event);
+
+ return 0;
+}
+
+static void task_clock_event_disable(struct perf_event *event)
+{
+ perf_swevent_cancel_hrtimer(event);
+ task_clock_event_update(event, event->ctx->time);
+
+}
+
+static void task_clock_event_read(struct perf_event *event)
+{
+ u64 time;
- atomic_inc(&perf_swevent_enabled[event_id]);
- event->destroy = sw_perf_event_destroy;
+ if (!in_nmi()) {
+ update_context_time(event->ctx);
+ time = event->ctx->time;
+ } else {
+ u64 now = perf_clock();
+ u64 delta = now - event->ctx->timestamp;
+ time = event->ctx->time + delta;
+ }
+
+ task_clock_event_update(event, time);
+}
+
+static int task_clock_event_init(struct perf_event *event)
+{
+ if (event->attr.type != PERF_TYPE_SOFTWARE)
+ return -ENOENT;
+
+ if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK)
+ return -ENOENT;
+
+ return 0;
+}
+
+static struct pmu perf_task_clock = {
+ .event_init = task_clock_event_init,
+ .enable = task_clock_event_enable,
+ .disable = task_clock_event_disable,
+ .read = task_clock_event_read,
+};
+
+static LIST_HEAD(pmus);
+static DEFINE_MUTEX(pmus_lock);
+static struct srcu_struct pmus_srcu;
+
+int perf_pmu_register(struct pmu *pmu)
+{
+ mutex_lock(&pmus_lock);
+ list_add_rcu(&pmu->entry, &pmus);
+ mutex_unlock(&pmus_lock);
+
+ return 0;
+}
+
+void perf_pmu_unregister(struct pmu *pmu)
+{
+ mutex_lock(&pmus_lock);
+ list_del_rcu(&pmu->entry);
+ mutex_unlock(&pmus_lock);
+
+ synchronize_srcu(&pmus_srcu);
+}
+
+struct pmu *perf_init_event(struct perf_event *event)
+{
+ struct pmu *pmu = NULL;
+ int idx;
+
+ idx = srcu_read_lock(&pmus_srcu);
+ list_for_each_entry_rcu(pmu, &pmus, entry) {
+ int ret = pmu->event_init(event);
+ if (!ret)
+ break;
+ if (ret != -ENOENT) {
+ pmu = ERR_PTR(ret);
+ break;
}
- pmu = &perf_ops_generic;
- break;
}
+ srcu_read_unlock(&pmus_srcu, idx);
return pmu;
}
perf_overflow_handler_t overflow_handler,
gfp_t gfpflags)
{
- const struct pmu *pmu;
+ struct pmu *pmu;
struct perf_event *event;
struct hw_perf_event *hwc;
long err;
if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP))
goto done;
- switch (attr->type) {
- case PERF_TYPE_RAW:
- case PERF_TYPE_HARDWARE:
- case PERF_TYPE_HW_CACHE:
- pmu = hw_perf_event_init(event);
- break;
-
- case PERF_TYPE_SOFTWARE:
- pmu = sw_perf_event_init(event);
- break;
-
- case PERF_TYPE_TRACEPOINT:
- pmu = tp_perf_event_init(event);
- break;
-
- case PERF_TYPE_BREAKPOINT:
- pmu = bp_perf_event_init(event);
- break;
-
+ pmu = perf_init_event(event);
- default:
- break;
- }
done:
err = 0;
if (!pmu)
atomic_inc(&nr_comm_events);
if (event->attr.task)
atomic_inc(&nr_task_events);
+ if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) {
+ err = get_callchain_buffers();
+ if (err) {
+ free_event(event);
+ return ERR_PTR(err);
+ }
+ }
}
return event;
{
unsigned int cpu = (long)hcpu;
- switch (action) {
+ switch (action & ~CPU_TASKS_FROZEN) {
case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
+ case CPU_DOWN_FAILED:
perf_event_init_cpu(cpu);
break;
+ case CPU_UP_CANCELED:
case CPU_DOWN_PREPARE:
- case CPU_DOWN_PREPARE_FROZEN:
perf_event_exit_cpu(cpu);
break;
return NOTIFY_OK;
}
-/*
- * This has to have a higher priority than migration_notifier in sched.c.
- */
-static struct notifier_block __cpuinitdata perf_cpu_nb = {
- .notifier_call = perf_cpu_notify,
- .priority = 20,
-};
-
void __init perf_event_init(void)
{
perf_event_init_all_cpus();
- perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_UP_PREPARE,
- (void *)(long)smp_processor_id());
- perf_cpu_notify(&perf_cpu_nb, (unsigned long)CPU_ONLINE,
- (void *)(long)smp_processor_id());
- register_cpu_notifier(&perf_cpu_nb);
+ init_srcu_struct(&pmus_srcu);
+ perf_pmu_register(&perf_swevent);
+ perf_pmu_register(&perf_cpu_clock);
+ perf_pmu_register(&perf_task_clock);
+ perf_tp_register();
+ perf_cpu_notifier(perf_cpu_notify);
}
static ssize_t perf_show_reserve_percpu(struct sysdev_class *class,