1 files changed, 47 insertions, 27 deletions

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 4acc77e049e5..958789fe4cef 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -166,6 +166,7 @@ static int trace_define_generic_fields(void)
 
 	__generic_field(int, CPU, FILTER_CPU);
 	__generic_field(int, cpu, FILTER_CPU);
+	__generic_field(int, common_cpu, FILTER_CPU);
 	__generic_field(char *, COMM, FILTER_COMM);
 	__generic_field(char *, comm, FILTER_COMM);
 
@@ -364,7 +365,6 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file,
 {
 	struct trace_event_call *call = file->event_call;
 	struct trace_array *tr = file->tr;
-	unsigned long file_flags = file->flags;
 	int ret = 0;
 	int disable;
 
@@ -388,6 +388,8 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file,
 				break;
 			disable = file->flags & EVENT_FILE_FL_SOFT_DISABLED;
 			clear_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags);
+			/* Disable use of trace_buffered_event */
+			trace_buffered_event_disable();
 		} else
 			disable = !(file->flags & EVENT_FILE_FL_SOFT_MODE);
 
@@ -426,6 +428,8 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file,
 			if (atomic_inc_return(&file->sm_ref) > 1)
 				break;
 			set_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags);
+			/* Enable use of trace_buffered_event */
+			trace_buffered_event_enable();
 		}
 
 		if (!(file->flags & EVENT_FILE_FL_ENABLED)) {
@@ -465,15 +469,6 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file,
 		break;
 	}
 
-	/* Enable or disable use of trace_buffered_event */
-	if ((file_flags & EVENT_FILE_FL_SOFT_DISABLED) !=
-	    (file->flags & EVENT_FILE_FL_SOFT_DISABLED)) {
-		if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
-			trace_buffered_event_enable();
-		else
-			trace_buffered_event_disable();
-	}
-
 	return ret;
 }
 
@@ -703,21 +698,33 @@ static void remove_subsystem(struct trace_subsystem_dir *dir)
 	}
 }
 
+void event_file_get(struct trace_event_file *file)
+{
+	atomic_inc(&file->ref);
+}
+
+void event_file_put(struct trace_event_file *file)
+{
+	if (WARN_ON_ONCE(!atomic_read(&file->ref))) {
+		if (file->flags & EVENT_FILE_FL_FREED)
+			kmem_cache_free(file_cachep, file);
+		return;
+	}
+
+	if (atomic_dec_and_test(&file->ref)) {
+		/* Count should only go to zero when it is freed */
+		if (WARN_ON_ONCE(!(file->flags & EVENT_FILE_FL_FREED)))
+			return;
+		kmem_cache_free(file_cachep, file);
+	}
+}
+
 static void remove_event_file_dir(struct trace_event_file *file)
 {
 	struct dentry *dir = file->dir;
-	struct dentry *child;
-
-	if (dir) {
-		spin_lock(&dir->d_lock);	/* probably unneeded */
-		list_for_each_entry(child, &dir->d_subdirs, d_child) {
-			if (d_really_is_positive(child))	/* probably unneeded */
-				d_inode(child)->i_private = NULL;
-		}
-		spin_unlock(&dir->d_lock);
 
+	if (dir)
 		tracefs_remove_recursive(dir);
-	}
 
 	list_del(&file->list);
 	remove_subsystem(file->system);
@@ -1038,7 +1045,7 @@ event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
 		flags = file->flags;
 	mutex_unlock(&event_mutex);
 
-	if (!file)
+	if (!file || flags & EVENT_FILE_FL_FREED)
 		return -ENODEV;
 
 	if (flags & EVENT_FILE_FL_ENABLED &&
@@ -1076,7 +1083,7 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
 		ret = -ENODEV;
 		mutex_lock(&event_mutex);
 		file = event_file_data(filp);
-		if (likely(file))
+		if (likely(file && !(file->flags & EVENT_FILE_FL_FREED)))
 			ret = ftrace_event_enable_disable(file, val);
 		mutex_unlock(&event_mutex);
 		break;
@@ -1345,7 +1352,7 @@ event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
 
 	mutex_lock(&event_mutex);
 	file = event_file_data(filp);
-	if (file)
+	if (file && !(file->flags & EVENT_FILE_FL_FREED))
 		print_event_filter(file, s);
 	mutex_unlock(&event_mutex);
 
@@ -1704,9 +1711,10 @@ static const struct file_operations ftrace_set_event_pid_fops = {
 };
 
 static const struct file_operations ftrace_enable_fops = {
-	.open = tracing_open_generic,
+	.open = tracing_open_file_tr,
 	.read = event_enable_read,
 	.write = event_enable_write,
+	.release = tracing_release_file_tr,
 	.llseek = default_llseek,
 };
 
@@ -1723,9 +1731,10 @@ static const struct file_operations ftrace_event_id_fops = {
 };
 
 static const struct file_operations ftrace_event_filter_fops = {
-	.open = tracing_open_generic,
+	.open = tracing_open_file_tr,
 	.read = event_filter_read,
 	.write = event_filter_write,
+	.release = tracing_release_file_tr,
 	.llseek = default_llseek,
 };
 
@@ -2239,6 +2248,7 @@ void trace_event_eval_update(struct trace_eval_map **map, int len)
 				update_event_printk(call, map[i]);
 			}
 		}
+		cond_resched();
 	}
 	up_write(&trace_event_sem);
 }
@@ -2266,6 +2276,7 @@ trace_create_new_event(struct trace_event_call *call,
 	atomic_set(&file->tm_ref, 0);
 	INIT_LIST_HEAD(&file->triggers);
 	list_add(&file->list, &tr->events);
+	event_file_get(file);
 
 	return file;
 }
@@ -2350,7 +2361,10 @@ static int probe_remove_event_call(struct trace_event_call *call)
 		 * TRACE_REG_UNREGISTER.
 		 */
 		if (file->flags & EVENT_FILE_FL_ENABLED)
-			return -EBUSY;
+			goto busy;
+
+		if (file->flags & EVENT_FILE_FL_WAS_ENABLED)
+			tr->clear_trace = true;
 		/*
 		 * The do_for_each_event_file_safe() is
 		 * a double loop. After finding the call for this
@@ -2363,6 +2377,12 @@ static int probe_remove_event_call(struct trace_event_call *call)
 	__trace_remove_event_call(call);
 
 	return 0;
+ busy:
+	/* No need to clear the trace now */
+	list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+		tr->clear_trace = false;
+	}
+	return -EBUSY;
 }
 
 /* Remove an event_call */
@@ -2430,7 +2450,7 @@ static void trace_module_remove_events(struct module *mod)
 	 * over from this module may be passed to the new module events and
 	 * unexpected results may occur.
 	 */
-	tracing_reset_all_online_cpus();
+	tracing_reset_all_online_cpus_unlocked();
 }
 
 static int trace_module_notify(struct notifier_block *self,