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-rw-r--r--kernel/perf_event.c200
1 files changed, 100 insertions, 100 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 8ca6e690ffe3..dae0e2f30293 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -5556,106 +5556,6 @@ err:
}
EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter);
-/*
- * inherit a event from parent task to child task:
- */
-static struct perf_event *
-inherit_event(struct perf_event *parent_event,
- struct task_struct *parent,
- struct perf_event_context *parent_ctx,
- struct task_struct *child,
- struct perf_event *group_leader,
- struct perf_event_context *child_ctx)
-{
- struct perf_event *child_event;
-
- /*
- * Instead of creating recursive hierarchies of events,
- * we link inherited events back to the original parent,
- * which has a filp for sure, which we use as the reference
- * count:
- */
- if (parent_event->parent)
- parent_event = parent_event->parent;
-
- child_event = perf_event_alloc(&parent_event->attr,
- parent_event->cpu,
- group_leader, parent_event,
- NULL);
- if (IS_ERR(child_event))
- return child_event;
- get_ctx(child_ctx);
-
- /*
- * Make the child state follow the state of the parent event,
- * not its attr.disabled bit. We hold the parent's mutex,
- * so we won't race with perf_event_{en, dis}able_family.
- */
- if (parent_event->state >= PERF_EVENT_STATE_INACTIVE)
- child_event->state = PERF_EVENT_STATE_INACTIVE;
- else
- child_event->state = PERF_EVENT_STATE_OFF;
-
- if (parent_event->attr.freq) {
- u64 sample_period = parent_event->hw.sample_period;
- struct hw_perf_event *hwc = &child_event->hw;
-
- hwc->sample_period = sample_period;
- hwc->last_period = sample_period;
-
- local64_set(&hwc->period_left, sample_period);
- }
-
- child_event->ctx = child_ctx;
- child_event->overflow_handler = parent_event->overflow_handler;
-
- /*
- * Link it up in the child's context:
- */
- add_event_to_ctx(child_event, child_ctx);
-
- /*
- * Get a reference to the parent filp - we will fput it
- * when the child event exits. This is safe to do because
- * we are in the parent and we know that the filp still
- * exists and has a nonzero count:
- */
- atomic_long_inc(&parent_event->filp->f_count);
-
- /*
- * Link this into the parent event's child list
- */
- WARN_ON_ONCE(parent_event->ctx->parent_ctx);
- mutex_lock(&parent_event->child_mutex);
- list_add_tail(&child_event->child_list, &parent_event->child_list);
- mutex_unlock(&parent_event->child_mutex);
-
- return child_event;
-}
-
-static int inherit_group(struct perf_event *parent_event,
- struct task_struct *parent,
- struct perf_event_context *parent_ctx,
- struct task_struct *child,
- struct perf_event_context *child_ctx)
-{
- struct perf_event *leader;
- struct perf_event *sub;
- struct perf_event *child_ctr;
-
- leader = inherit_event(parent_event, parent, parent_ctx,
- child, NULL, child_ctx);
- if (IS_ERR(leader))
- return PTR_ERR(leader);
- list_for_each_entry(sub, &parent_event->sibling_list, group_entry) {
- child_ctr = inherit_event(sub, parent, parent_ctx,
- child, leader, child_ctx);
- if (IS_ERR(child_ctr))
- return PTR_ERR(child_ctr);
- }
- return 0;
-}
-
static void sync_child_event(struct perf_event *child_event,
struct task_struct *child)
{
@@ -5844,6 +5744,106 @@ again:
put_ctx(ctx);
}
+/*
+ * inherit a event from parent task to child task:
+ */
+static struct perf_event *
+inherit_event(struct perf_event *parent_event,
+ struct task_struct *parent,
+ struct perf_event_context *parent_ctx,
+ struct task_struct *child,
+ struct perf_event *group_leader,
+ struct perf_event_context *child_ctx)
+{
+ struct perf_event *child_event;
+
+ /*
+ * Instead of creating recursive hierarchies of events,
+ * we link inherited events back to the original parent,
+ * which has a filp for sure, which we use as the reference
+ * count:
+ */
+ if (parent_event->parent)
+ parent_event = parent_event->parent;
+
+ child_event = perf_event_alloc(&parent_event->attr,
+ parent_event->cpu,
+ group_leader, parent_event,
+ NULL);
+ if (IS_ERR(child_event))
+ return child_event;
+ get_ctx(child_ctx);
+
+ /*
+ * Make the child state follow the state of the parent event,
+ * not its attr.disabled bit. We hold the parent's mutex,
+ * so we won't race with perf_event_{en, dis}able_family.
+ */
+ if (parent_event->state >= PERF_EVENT_STATE_INACTIVE)
+ child_event->state = PERF_EVENT_STATE_INACTIVE;
+ else
+ child_event->state = PERF_EVENT_STATE_OFF;
+
+ if (parent_event->attr.freq) {
+ u64 sample_period = parent_event->hw.sample_period;
+ struct hw_perf_event *hwc = &child_event->hw;
+
+ hwc->sample_period = sample_period;
+ hwc->last_period = sample_period;
+
+ local64_set(&hwc->period_left, sample_period);
+ }
+
+ child_event->ctx = child_ctx;
+ child_event->overflow_handler = parent_event->overflow_handler;
+
+ /*
+ * Link it up in the child's context:
+ */
+ add_event_to_ctx(child_event, child_ctx);
+
+ /*
+ * Get a reference to the parent filp - we will fput it
+ * when the child event exits. This is safe to do because
+ * we are in the parent and we know that the filp still
+ * exists and has a nonzero count:
+ */
+ atomic_long_inc(&parent_event->filp->f_count);
+
+ /*
+ * Link this into the parent event's child list
+ */
+ WARN_ON_ONCE(parent_event->ctx->parent_ctx);
+ mutex_lock(&parent_event->child_mutex);
+ list_add_tail(&child_event->child_list, &parent_event->child_list);
+ mutex_unlock(&parent_event->child_mutex);
+
+ return child_event;
+}
+
+static int inherit_group(struct perf_event *parent_event,
+ struct task_struct *parent,
+ struct perf_event_context *parent_ctx,
+ struct task_struct *child,
+ struct perf_event_context *child_ctx)
+{
+ struct perf_event *leader;
+ struct perf_event *sub;
+ struct perf_event *child_ctr;
+
+ leader = inherit_event(parent_event, parent, parent_ctx,
+ child, NULL, child_ctx);
+ if (IS_ERR(leader))
+ return PTR_ERR(leader);
+ list_for_each_entry(sub, &parent_event->sibling_list, group_entry) {
+ child_ctr = inherit_event(sub, parent, parent_ctx,
+ child, leader, child_ctx);
+ if (IS_ERR(child_ctr))
+ return PTR_ERR(child_ctr);
+ }
+ return 0;
+}
+
static int
inherit_task_group(struct perf_event *event, struct task_struct *parent,
struct perf_event_context *parent_ctx,
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