perf: Register PMU implementations
Simple registration interface for struct pmu, this provides the
infrastructure for removing all the weak functions.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus <paulus@samba.org>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Yanmin <yanmin_zhang@linux.intel.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index fb46fd1..288ce43 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -31,7 +31,6 @@
#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>
@@ -72,14 +71,6 @@
*/
static DEFINE_SPINLOCK(perf_resource_lock);
-/*
- * Architecture provided APIs - weak aliases:
- */
-extern __weak 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(); }
@@ -4501,182 +4492,6 @@
return 0;
}
-static 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 */
-};
-
-/*
- * hrtimer based swevent callback
- */
-
-static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
-{
- enum hrtimer_restart ret = HRTIMER_RESTART;
- struct perf_sample_data data;
- struct pt_regs *regs;
- struct perf_event *event;
- u64 period;
-
- event = container_of(hrtimer, struct perf_event, hw.hrtimer);
- event->pmu->read(event);
-
- 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 ret;
-}
-
-static void perf_swevent_start_hrtimer(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 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 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)
@@ -4783,17 +4598,63 @@
return err;
}
-#ifdef CONFIG_EVENT_TRACING
+atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
-static 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)
{
@@ -4849,10 +4710,13 @@
perf_trace_destroy(event);
}
-static 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.
@@ -4860,15 +4724,30 @@
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)
@@ -4896,9 +4775,8 @@
#else
-static 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)
@@ -4913,24 +4791,6 @@
#endif /* CONFIG_EVENT_TRACING */
#ifdef CONFIG_HAVE_HW_BREAKPOINT
-static void bp_perf_event_destroy(struct perf_event *event)
-{
- release_bp_slot(event);
-}
-
-static struct pmu *bp_perf_event_init(struct perf_event *bp)
-{
- int err;
-
- err = register_perf_hw_breakpoint(bp);
- if (err)
- return ERR_PTR(err);
-
- bp->destroy = bp_perf_event_destroy;
-
- return &perf_ops_bp;
-}
-
void perf_bp_event(struct perf_event *bp, void *data)
{
struct perf_sample_data sample;
@@ -4941,77 +4801,237 @@
if (!perf_exclude_event(bp, regs))
perf_swevent_add(bp, 1, 1, &sample, regs);
}
-#else
-static struct pmu *bp_perf_event_init(struct perf_event *bp)
-{
- return NULL;
-}
-
-void perf_bp_event(struct perf_event *bp, void *regs)
-{
-}
#endif
-atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
+/*
+ * hrtimer based swevent callback
+ */
-static void sw_perf_event_destroy(struct perf_event *event)
+static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
{
- u64 event_id = event->attr.config;
+ enum hrtimer_restart ret = HRTIMER_RESTART;
+ struct perf_sample_data data;
+ struct pt_regs *regs;
+ struct perf_event *event;
+ u64 period;
- WARN_ON(event->parent);
+ event = container_of(hrtimer, struct perf_event, hw.hrtimer);
+ event->pmu->read(event);
- atomic_dec(&perf_swevent_enabled[event_id]);
- swevent_hlist_put(event);
+ 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 ret;
}
-static struct pmu *sw_perf_event_init(struct perf_event *event)
+static void perf_swevent_start_hrtimer(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_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_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_event_disable(struct perf_event *event)
+{
+ perf_swevent_cancel_hrtimer(event);
+ cpu_clock_event_update(event);
+}
+
+static void cpu_clock_event_read(struct perf_event *event)
+{
+ cpu_clock_event_update(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 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)
+{
+ u64 prev;
+ s64 delta;
+
+ prev = local64_xchg(&event->hw.prev_count, now);
+ delta = now - prev;
+ local64_add(delta, &event->count);
+}
+
+static int task_clock_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_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;
+
+ 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;
- u64 event_id = event->attr.config;
+ int idx;
- /*
- * 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;
-
- 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;
-
- 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);
-
- atomic_inc(&perf_swevent_enabled[event_id]);
- event->destroy = sw_perf_event_destroy;
+ 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;
}
@@ -5092,29 +5112,8 @@
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;
+ pmu = perf_init_event(event);
- 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;
-
-
- default:
- break;
- }
done:
err = 0;
if (!pmu)
@@ -5979,22 +5978,15 @@
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,