1 files changed, 28 insertions, 15 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 301079d06f24..b0cd86501c30 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -908,6 +908,15 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
 }
 
 /*
+ * Initialize event state based on the perf_event_attr::disabled.
+ */
+static inline void perf_event__state_init(struct perf_event *event)
+{
+	event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF :
+					      PERF_EVENT_STATE_INACTIVE;
+}
+
+/*
  * Called at perf_event creation and when events are attached/detached from a
  * group.
  */
@@ -3682,7 +3691,7 @@ unlock:
 
 static int perf_fasync(int fd, struct file *filp, int on)
 {
-	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	struct perf_event *event = filp->private_data;
 	int retval;
 
@@ -5117,7 +5126,6 @@ static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
 {
 	struct swevent_htable *swhash = &__get_cpu_var(swevent_htable);
 	struct perf_event *event;
-	struct hlist_node *node;
 	struct hlist_head *head;
 
 	rcu_read_lock();
@@ -5125,7 +5133,7 @@ static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
 	if (!head)
 		goto end;
 
-	hlist_for_each_entry_rcu(event, node, head, hlist_entry) {
+	hlist_for_each_entry_rcu(event, head, hlist_entry) {
 		if (perf_swevent_match(event, type, event_id, data, regs))
 			perf_swevent_event(event, nr, data, regs);
 	}
@@ -5410,7 +5418,6 @@ void perf_tp_event(u64 addr, u64 count, void *record, int entry_size,
 {
 	struct perf_sample_data data;
 	struct perf_event *event;
-	struct hlist_node *node;
 
 	struct perf_raw_record raw = {
 		.size = entry_size,
@@ -5420,7 +5427,7 @@ void perf_tp_event(u64 addr, u64 count, void *record, int entry_size,
 	perf_sample_data_init(&data, addr, 0);
 	data.raw = &raw;
 
-	hlist_for_each_entry_rcu(event, node, head, hlist_entry) {
+	hlist_for_each_entry_rcu(event, head, hlist_entry) {
 		if (perf_tp_event_match(event, &data, regs))
 			perf_swevent_event(event, count, &data, regs);
 	}
@@ -5956,13 +5963,9 @@ int perf_pmu_register(struct pmu *pmu, char *name, int type)
 	pmu->name = name;
 
 	if (type < 0) {
-		int err = idr_pre_get(&pmu_idr, GFP_KERNEL);
-		if (!err)
-			goto free_pdc;
-
-		err = idr_get_new_above(&pmu_idr, pmu, PERF_TYPE_MAX, &type);
-		if (err) {
-			ret = err;
+		type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL);
+		if (type < 0) {
+			ret = type;
 			goto free_pdc;
 		}
 	}
@@ -6162,11 +6165,14 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
 
 	if (task) {
 		event->attach_state = PERF_ATTACH_TASK;
+
+		if (attr->type == PERF_TYPE_TRACEPOINT)
+			event->hw.tp_target = task;
 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 		/*
 		 * hw_breakpoint is a bit difficult here..
 		 */
-		if (attr->type == PERF_TYPE_BREAKPOINT)
+		else if (attr->type == PERF_TYPE_BREAKPOINT)
 			event->hw.bp_target = task;
 #endif
 	}
@@ -6179,8 +6185,7 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
 	event->overflow_handler	= overflow_handler;
 	event->overflow_handler_context = context;
 
-	if (attr->disabled)
-		event->state = PERF_EVENT_STATE_OFF;
+	perf_event__state_init(event);
 
 	pmu = NULL;
 
@@ -6609,9 +6614,17 @@ SYSCALL_DEFINE5(perf_event_open,
 
 		mutex_lock(&gctx->mutex);
 		perf_remove_from_context(group_leader);
+
+		/*
+		 * Removing from the context ends up with disabled
+		 * event. What we want here is event in the initial
+		 * startup state, ready to be add into new context.
+		 */
+		perf_event__state_init(group_leader);
 		list_for_each_entry(sibling, &group_leader->sibling_list,
 				    group_entry) {
 			perf_remove_from_context(sibling);
+			perf_event__state_init(sibling);
 			put_ctx(gctx);
 		}
 		mutex_unlock(&gctx->mutex);