/*
* Architecture provided APIs - weak aliases:
*/
-extern __weak const struct pmu *hw_perf_event_init(struct perf_event *event)
+extern __weak struct pmu *hw_perf_event_init(struct perf_event *event)
{
return NULL;
}
}
}
+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;
}
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)
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:
*/
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
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 = {
+static struct pmu perf_ops_generic = {
.enable = perf_swevent_enable,
.disable = perf_swevent_disable,
.start = perf_swevent_int,
cpu_clock_perf_event_update(event);
}
-static const struct pmu perf_ops_cpu_clock = {
+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,
task_clock_perf_event_update(event, time);
}
-static const struct pmu perf_ops_task_clock = {
+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,
#ifdef CONFIG_EVENT_TRACING
-static const struct pmu perf_ops_tracepoint = {
+static struct pmu perf_ops_tracepoint = {
.enable = perf_trace_enable,
.disable = perf_trace_disable,
.start = perf_swevent_int,
perf_trace_destroy(event);
}
-static const struct pmu *tp_perf_event_init(struct perf_event *event)
+static struct pmu *tp_perf_event_init(struct perf_event *event)
{
int err;
#else
-static const struct pmu *tp_perf_event_init(struct perf_event *event)
+static struct pmu *tp_perf_event_init(struct perf_event *event)
{
return NULL;
}
release_bp_slot(event);
}
-static const struct pmu *bp_perf_event_init(struct perf_event *bp)
+static struct pmu *bp_perf_event_init(struct perf_event *bp)
{
int err;
perf_swevent_add(bp, 1, 1, &sample, regs);
}
#else
-static const struct pmu *bp_perf_event_init(struct perf_event *bp)
+static struct pmu *bp_perf_event_init(struct perf_event *bp)
{
return NULL;
}
swevent_hlist_put(event);
}
-static const struct pmu *sw_perf_event_init(struct perf_event *event)
+static struct pmu *sw_perf_event_init(struct perf_event *event)
{
- const struct pmu *pmu = NULL;
+ struct pmu *pmu = NULL;
u64 event_id = event->attr.config;
/*
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;
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;
projects / mv-sheeva.git / blobdiff