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-rw-r--r--kernel/perf_counter.c338
1 files changed, 236 insertions, 102 deletions
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index b0b20a07f39..534e20d14d6 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -88,6 +88,7 @@ void __weak hw_perf_disable(void) { barrier(); }
void __weak hw_perf_enable(void) { barrier(); }
void __weak hw_perf_counter_setup(int cpu) { barrier(); }
+void __weak hw_perf_counter_setup_online(int cpu) { barrier(); }
int __weak
hw_perf_group_sched_in(struct perf_counter *group_leader,
@@ -306,6 +307,10 @@ counter_sched_out(struct perf_counter *counter,
return;
counter->state = PERF_COUNTER_STATE_INACTIVE;
+ if (counter->pending_disable) {
+ counter->pending_disable = 0;
+ counter->state = PERF_COUNTER_STATE_OFF;
+ }
counter->tstamp_stopped = ctx->time;
counter->pmu->disable(counter);
counter->oncpu = -1;
@@ -1691,7 +1696,32 @@ static int perf_release(struct inode *inode, struct file *file)
return 0;
}
-static u64 perf_counter_read_tree(struct perf_counter *counter)
+static int perf_counter_read_size(struct perf_counter *counter)
+{
+ int entry = sizeof(u64); /* value */
+ int size = 0;
+ int nr = 1;
+
+ if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+ size += sizeof(u64);
+
+ if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+ size += sizeof(u64);
+
+ if (counter->attr.read_format & PERF_FORMAT_ID)
+ entry += sizeof(u64);
+
+ if (counter->attr.read_format & PERF_FORMAT_GROUP) {
+ nr += counter->group_leader->nr_siblings;
+ size += sizeof(u64);
+ }
+
+ size += entry * nr;
+
+ return size;
+}
+
+static u64 perf_counter_read_value(struct perf_counter *counter)
{
struct perf_counter *child;
u64 total = 0;
@@ -1703,14 +1733,96 @@ static u64 perf_counter_read_tree(struct perf_counter *counter)
return total;
}
+static int perf_counter_read_entry(struct perf_counter *counter,
+ u64 read_format, char __user *buf)
+{
+ int n = 0, count = 0;
+ u64 values[2];
+
+ values[n++] = perf_counter_read_value(counter);
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(counter);
+
+ count = n * sizeof(u64);
+
+ if (copy_to_user(buf, values, count))
+ return -EFAULT;
+
+ return count;
+}
+
+static int perf_counter_read_group(struct perf_counter *counter,
+ u64 read_format, char __user *buf)
+{
+ struct perf_counter *leader = counter->group_leader, *sub;
+ int n = 0, size = 0, err = -EFAULT;
+ u64 values[3];
+
+ values[n++] = 1 + leader->nr_siblings;
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+ values[n++] = leader->total_time_enabled +
+ atomic64_read(&leader->child_total_time_enabled);
+ }
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+ values[n++] = leader->total_time_running +
+ atomic64_read(&leader->child_total_time_running);
+ }
+
+ size = n * sizeof(u64);
+
+ if (copy_to_user(buf, values, size))
+ return -EFAULT;
+
+ err = perf_counter_read_entry(leader, read_format, buf + size);
+ if (err < 0)
+ return err;
+
+ size += err;
+
+ list_for_each_entry(sub, &leader->sibling_list, list_entry) {
+ err = perf_counter_read_entry(counter, read_format,
+ buf + size);
+ if (err < 0)
+ return err;
+
+ size += err;
+ }
+
+ return size;
+}
+
+static int perf_counter_read_one(struct perf_counter *counter,
+ u64 read_format, char __user *buf)
+{
+ u64 values[4];
+ int n = 0;
+
+ values[n++] = perf_counter_read_value(counter);
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+ values[n++] = counter->total_time_enabled +
+ atomic64_read(&counter->child_total_time_enabled);
+ }
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+ values[n++] = counter->total_time_running +
+ atomic64_read(&counter->child_total_time_running);
+ }
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(counter);
+
+ if (copy_to_user(buf, values, n * sizeof(u64)))
+ return -EFAULT;
+
+ return n * sizeof(u64);
+}
+
/*
* Read the performance counter - simple non blocking version for now
*/
static ssize_t
perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count)
{
- u64 values[4];
- int n;
+ u64 read_format = counter->attr.read_format;
+ int ret;
/*
* Return end-of-file for a read on a counter that is in
@@ -1720,28 +1832,18 @@ perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count)
if (counter->state == PERF_COUNTER_STATE_ERROR)
return 0;
+ if (count < perf_counter_read_size(counter))
+ return -ENOSPC;
+
WARN_ON_ONCE(counter->ctx->parent_ctx);
mutex_lock(&counter->child_mutex);
- values[0] = perf_counter_read_tree(counter);
- n = 1;
- if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
- values[n++] = counter->total_time_enabled +
- atomic64_read(&counter->child_total_time_enabled);
- if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
- values[n++] = counter->total_time_running +
- atomic64_read(&counter->child_total_time_running);
- if (counter->attr.read_format & PERF_FORMAT_ID)
- values[n++] = primary_counter_id(counter);
+ if (read_format & PERF_FORMAT_GROUP)
+ ret = perf_counter_read_group(counter, read_format, buf);
+ else
+ ret = perf_counter_read_one(counter, read_format, buf);
mutex_unlock(&counter->child_mutex);
- if (count < n * sizeof(u64))
- return -EINVAL;
- count = n * sizeof(u64);
-
- if (copy_to_user(buf, values, count))
- return -EFAULT;
-
- return count;
+ return ret;
}
static ssize_t
@@ -2245,7 +2347,7 @@ static void perf_pending_counter(struct perf_pending_entry *entry)
if (counter->pending_disable) {
counter->pending_disable = 0;
- perf_counter_disable(counter);
+ __perf_counter_disable(counter);
}
if (counter->pending_wakeup) {
@@ -2630,7 +2732,80 @@ static u32 perf_counter_tid(struct perf_counter *counter, struct task_struct *p)
return task_pid_nr_ns(p, counter->ns);
}
-static void perf_counter_output(struct perf_counter *counter, int nmi,
+static void perf_output_read_one(struct perf_output_handle *handle,
+ struct perf_counter *counter)
+{
+ u64 read_format = counter->attr.read_format;
+ u64 values[4];
+ int n = 0;
+
+ values[n++] = atomic64_read(&counter->count);
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
+ values[n++] = counter->total_time_enabled +
+ atomic64_read(&counter->child_total_time_enabled);
+ }
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
+ values[n++] = counter->total_time_running +
+ atomic64_read(&counter->child_total_time_running);
+ }
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(counter);
+
+ perf_output_copy(handle, values, n * sizeof(u64));
+}
+
+/*
+ * XXX PERF_FORMAT_GROUP vs inherited counters seems difficult.
+ */
+static void perf_output_read_group(struct perf_output_handle *handle,
+ struct perf_counter *counter)
+{
+ struct perf_counter *leader = counter->group_leader, *sub;
+ u64 read_format = counter->attr.read_format;
+ u64 values[5];
+ int n = 0;
+
+ values[n++] = 1 + leader->nr_siblings;
+
+ if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
+ values[n++] = leader->total_time_enabled;
+
+ if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
+ values[n++] = leader->total_time_running;
+
+ if (leader != counter)
+ leader->pmu->read(leader);
+
+ values[n++] = atomic64_read(&leader->count);
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(leader);
+
+ perf_output_copy(handle, values, n * sizeof(u64));
+
+ list_for_each_entry(sub, &leader->sibling_list, list_entry) {
+ n = 0;
+
+ if (sub != counter)
+ sub->pmu->read(sub);
+
+ values[n++] = atomic64_read(&sub->count);
+ if (read_format & PERF_FORMAT_ID)
+ values[n++] = primary_counter_id(sub);
+
+ perf_output_copy(handle, values, n * sizeof(u64));
+ }
+}
+
+static void perf_output_read(struct perf_output_handle *handle,
+ struct perf_counter *counter)
+{
+ if (counter->attr.read_format & PERF_FORMAT_GROUP)
+ perf_output_read_group(handle, counter);
+ else
+ perf_output_read_one(handle, counter);
+}
+
+void perf_counter_output(struct perf_counter *counter, int nmi,
struct perf_sample_data *data)
{
int ret;
@@ -2641,10 +2816,6 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
struct {
u32 pid, tid;
} tid_entry;
- struct {
- u64 id;
- u64 counter;
- } group_entry;
struct perf_callchain_entry *callchain = NULL;
int callchain_size = 0;
u64 time;
@@ -2699,10 +2870,8 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
if (sample_type & PERF_SAMPLE_PERIOD)
header.size += sizeof(u64);
- if (sample_type & PERF_SAMPLE_GROUP) {
- header.size += sizeof(u64) +
- counter->nr_siblings * sizeof(group_entry);
- }
+ if (sample_type & PERF_SAMPLE_READ)
+ header.size += perf_counter_read_size(counter);
if (sample_type & PERF_SAMPLE_CALLCHAIN) {
callchain = perf_callchain(data->regs);
@@ -2759,26 +2928,8 @@ static void perf_counter_output(struct perf_counter *counter, int nmi,
if (sample_type & PERF_SAMPLE_PERIOD)
perf_output_put(&handle, data->period);
- /*
- * XXX PERF_SAMPLE_GROUP vs inherited counters seems difficult.
- */
- if (sample_type & PERF_SAMPLE_GROUP) {
- struct perf_counter *leader, *sub;
- u64 nr = counter->nr_siblings;
-
- perf_output_put(&handle, nr);
-
- leader = counter->group_leader;
- list_for_each_entry(sub, &leader->sibling_list, list_entry) {
- if (sub != counter)
- sub->pmu->read(sub);
-
- group_entry.id = primary_counter_id(sub);
- group_entry.counter = atomic64_read(&sub->count);
-
- perf_output_put(&handle, group_entry);
- }
- }
+ if (sample_type & PERF_SAMPLE_READ)
+ perf_output_read(&handle, counter);
if (sample_type & PERF_SAMPLE_CALLCHAIN) {
if (callchain)
@@ -2817,8 +2968,6 @@ struct perf_read_event {
u32 pid;
u32 tid;
- u64 value;
- u64 format[3];
};
static void
@@ -2830,34 +2979,20 @@ perf_counter_read_event(struct perf_counter *counter,
.header = {
.type = PERF_EVENT_READ,
.misc = 0,
- .size = sizeof(event) - sizeof(event.format),
+ .size = sizeof(event) + perf_counter_read_size(counter),
},
.pid = perf_counter_pid(counter, task),
.tid = perf_counter_tid(counter, task),
- .value = atomic64_read(&counter->count),
};
- int ret, i = 0;
-
- if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
- event.header.size += sizeof(u64);
- event.format[i++] = counter->total_time_enabled;
- }
-
- if (counter->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
- event.header.size += sizeof(u64);
- event.format[i++] = counter->total_time_running;
- }
-
- if (counter->attr.read_format & PERF_FORMAT_ID) {
- event.header.size += sizeof(u64);
- event.format[i++] = primary_counter_id(counter);
- }
+ int ret;
ret = perf_output_begin(&handle, counter, event.header.size, 0, 0);
if (ret)
return;
- perf_output_copy(&handle, &event, event.header.size);
+ perf_output_put(&handle, event);
+ perf_output_read(&handle, counter);
+
perf_output_end(&handle);
}
@@ -2893,10 +3028,10 @@ static void perf_counter_task_output(struct perf_counter *counter,
return;
task_event->event.pid = perf_counter_pid(counter, task);
- task_event->event.ppid = perf_counter_pid(counter, task->real_parent);
+ task_event->event.ppid = perf_counter_pid(counter, current);
task_event->event.tid = perf_counter_tid(counter, task);
- task_event->event.ptid = perf_counter_tid(counter, task->real_parent);
+ task_event->event.ptid = perf_counter_tid(counter, current);
perf_output_put(&handle, task_event->event);
perf_output_end(&handle);
@@ -3443,40 +3578,32 @@ static void perf_swcounter_add(struct perf_counter *counter, u64 nr,
static int perf_swcounter_is_counting(struct perf_counter *counter)
{
- struct perf_counter_context *ctx;
- unsigned long flags;
- int count;
-
+ /*
+ * The counter is active, we're good!
+ */
if (counter->state == PERF_COUNTER_STATE_ACTIVE)
return 1;
+ /*
+ * The counter is off/error, not counting.
+ */
if (counter->state != PERF_COUNTER_STATE_INACTIVE)
return 0;
/*
- * If the counter is inactive, it could be just because
- * its task is scheduled out, or because it's in a group
- * which could not go on the PMU. We want to count in
- * the first case but not the second. If the context is
- * currently active then an inactive software counter must
- * be the second case. If it's not currently active then
- * we need to know whether the counter was active when the
- * context was last active, which we can determine by
- * comparing counter->tstamp_stopped with ctx->time.
- *
- * We are within an RCU read-side critical section,
- * which protects the existence of *ctx.
+ * The counter is inactive, if the context is active
+ * we're part of a group that didn't make it on the 'pmu',
+ * not counting.
*/
- ctx = counter->ctx;
- spin_lock_irqsave(&ctx->lock, flags);
- count = 1;
- /* Re-check state now we have the lock */
- if (counter->state < PERF_COUNTER_STATE_INACTIVE ||
- counter->ctx->is_active ||
- counter->tstamp_stopped < ctx->time)
- count = 0;
- spin_unlock_irqrestore(&ctx->lock, flags);
- return count;
+ if (counter->ctx->is_active)
+ return 0;
+
+ /*
+ * We're inactive and the context is too, this means the
+ * task is scheduled out, we're counting events that happen
+ * to us, like migration events.
+ */
+ return 1;
}
static int perf_swcounter_match(struct perf_counter *counter,
@@ -3928,9 +4055,9 @@ perf_counter_alloc(struct perf_counter_attr *attr,
atomic64_set(&hwc->period_left, hwc->sample_period);
/*
- * we currently do not support PERF_SAMPLE_GROUP on inherited counters
+ * we currently do not support PERF_FORMAT_GROUP on inherited counters
*/
- if (attr->inherit && (attr->sample_type & PERF_SAMPLE_GROUP))
+ if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP))
goto done;
switch (attr->type) {
@@ -4592,6 +4719,11 @@ perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu)
perf_counter_init_cpu(cpu);
break;
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ hw_perf_counter_setup_online(cpu);
+ break;
+
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
perf_counter_exit_cpu(cpu);
@@ -4616,6 +4748,8 @@ void __init perf_counter_init(void)
{
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);
}