ext4: Remove unnecessary wait_event ext4_run_lazyinit_thread()

For some reason we have been waiting for lazyinit thread to start in the
ext4_run_lazyinit_thread() but it is not needed since it was jus
unnecessary complexity, so get rid of it. We can also remove li_task and
li_wait_task since it is not used anymore.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>

fs/ext4/ext4.h

@@ -1605,8 +1605,6 @@ void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
  */
 struct ext4_lazy_init {
 	unsigned long		li_state;
-	wait_queue_head_t	li_wait_task;
-	struct task_struct	*li_task;
 	struct list_head	li_request_list;
 	struct mutex		li_list_mtx;
 };

fs/ext4/super.c

@@ -2768,9 +2768,6 @@ static int ext4_lazyinit_thread(void *arg)
 
 	BUG_ON(NULL == eli);
 
-	eli->li_task = current;
-	wake_up(&eli->li_wait_task);
-
 cont_thread:
 	while (true) {
 		next_wakeup = MAX_JIFFY_OFFSET;
@@ -2833,9 +2830,6 @@ static int ext4_lazyinit_thread(void *arg)
 		goto cont_thread;
 	}
 	mutex_unlock(&eli->li_list_mtx);
-	eli->li_task = NULL;
-	wake_up(&eli->li_wait_task);
-
 	kfree(ext4_li_info);
 	ext4_li_info = NULL;
 	mutex_unlock(&ext4_li_mtx);
@@ -2872,8 +2866,6 @@ static int ext4_run_lazyinit_thread(void)
 		return err;
 	}
 	ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
-
-	wait_event(ext4_li_info->li_wait_task, ext4_li_info->li_task != NULL);
 	return 0;
 }
 
@@ -2908,11 +2900,9 @@ static int ext4_li_info_new(void)
 	if (!eli)
 		return -ENOMEM;
 
-	eli->li_task = NULL;
 	INIT_LIST_HEAD(&eli->li_request_list);
 	mutex_init(&eli->li_list_mtx);
 
-	init_waitqueue_head(&eli->li_wait_task);
 	eli->li_state |= EXT4_LAZYINIT_QUIT;
 
 	ext4_li_info = eli;