tracing: Introduce remove_event_file_dir()
Oleg Nesterov [Fri, 26 Jul 2013 17:25:47 +0000 (19:25 +0200)]
commit f6a84bdc75b5c11621dec58db73fe102cbaf40cc upstream.

Preparation for the next patch. Extract the common code from
remove_event_from_tracers() and __trace_remove_event_dirs()
into the new helper, remove_event_file_dir().

The patch looks more complicated than it actually is, it also
moves remove_subsystem() up to avoid the forward declaration.

Link: http://lkml.kernel.org/r/20130726172547.GA3629@redhat.com

Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kernel/trace/trace_events.c

index 09782d6..422f99d 100644 (file)
@@ -407,11 +407,31 @@ static void put_system(struct ftrace_subsystem_dir *dir)
        mutex_unlock(&event_mutex);
 }
 
+static void remove_subsystem(struct ftrace_subsystem_dir *dir)
+{
+       if (!dir)
+               return;
+
+       if (!--dir->nr_events) {
+               debugfs_remove_recursive(dir->entry);
+               list_del(&dir->list);
+               __put_system_dir(dir);
+       }
+}
+
 static void *event_file_data(struct file *filp)
 {
        return ACCESS_ONCE(file_inode(filp)->i_private);
 }
 
+static void remove_event_file_dir(struct ftrace_event_file *file)
+{
+       list_del(&file->list);
+       debugfs_remove_recursive(file->dir);
+       remove_subsystem(file->system);
+       kmem_cache_free(file_cachep, file);
+}
+
 /*
  * Open and update trace_array ref count.
  * Must have the current trace_array passed to it.
@@ -1571,33 +1591,16 @@ event_create_dir(struct dentry *parent,
        return 0;
 }
 
-static void remove_subsystem(struct ftrace_subsystem_dir *dir)
-{
-       if (!dir)
-               return;
-
-       if (!--dir->nr_events) {
-               debugfs_remove_recursive(dir->entry);
-               list_del(&dir->list);
-               __put_system_dir(dir);
-       }
-}
-
 static void remove_event_from_tracers(struct ftrace_event_call *call)
 {
        struct ftrace_event_file *file;
        struct trace_array *tr;
 
        do_for_each_event_file_safe(tr, file) {
-
                if (file->event_call != call)
                        continue;
 
-               list_del(&file->list);
-               debugfs_remove_recursive(file->dir);
-               remove_subsystem(file->system);
-               kmem_cache_free(file_cachep, file);
-
+               remove_event_file_dir(file);
                /*
                 * The do_for_each_event_file_safe() is
                 * a double loop. After finding the call for this
@@ -2330,12 +2333,8 @@ __trace_remove_event_dirs(struct trace_array *tr)
 {
        struct ftrace_event_file *file, *next;
 
-       list_for_each_entry_safe(file, next, &tr->events, list) {
-               list_del(&file->list);
-               debugfs_remove_recursive(file->dir);
-               remove_subsystem(file->system);
-               kmem_cache_free(file_cachep, file);
-       }
+       list_for_each_entry_safe(file, next, &tr->events, list)
+               remove_event_file_dir(file);
 }
 
 static void