jbd2: remove unused waitqueues

j_wait_logspace and j_wait_checkpoint are unused.  Remove them.
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

fs/jbd2/checkpoint.c

@@ -625,10 +625,6 @@ int __jbd2_journal_remove_checkpoint(struct journal_head *jh)
 
 	__jbd2_journal_drop_transaction(journal, transaction);
 	jbd2_journal_free_transaction(transaction);
-
-	/* Just in case anybody was waiting for more transactions to be
-           checkpointed... */
-	wake_up(&journal->j_wait_logspace);
 	ret = 1;
 out:
 	return ret;

fs/jbd2/journal.c

@@ -1027,9 +1027,7 @@ static journal_t * journal_init_common (void)
 		return NULL;
 
 	init_waitqueue_head(&journal->j_wait_transaction_locked);
-	init_waitqueue_head(&journal->j_wait_logspace);
 	init_waitqueue_head(&journal->j_wait_done_commit);
-	init_waitqueue_head(&journal->j_wait_checkpoint);
 	init_waitqueue_head(&journal->j_wait_commit);
 	init_waitqueue_head(&journal->j_wait_updates);
 	mutex_init(&journal->j_barrier);

include/linux/jbd2.h

@@ -687,9 +687,7 @@ jbd2_time_diff(unsigned long start, unsigned long end)
  *  waiting for checkpointing
  * @j_wait_transaction_locked: Wait queue for waiting for a locked transaction
  *  to start committing, or for a barrier lock to be released
- * @j_wait_logspace: Wait queue for waiting for checkpointing to complete
  * @j_wait_done_commit: Wait queue for waiting for commit to complete
- * @j_wait_checkpoint:  Wait queue to trigger checkpointing
  * @j_wait_commit: Wait queue to trigger commit
  * @j_wait_updates: Wait queue to wait for updates to complete
  * @j_checkpoint_mutex: Mutex for locking against concurrent checkpoints
@@ -794,15 +792,9 @@ struct journal_s
 	 */
 	wait_queue_head_t	j_wait_transaction_locked;
 
-	/* Wait queue for waiting for checkpointing to complete */
-	wait_queue_head_t	j_wait_logspace;
-
 	/* Wait queue for waiting for commit to complete */
 	wait_queue_head_t	j_wait_done_commit;
 
-	/* Wait queue to trigger checkpointing */
-	wait_queue_head_t	j_wait_checkpoint;
-
 	/* Wait queue to trigger commit */
 	wait_queue_head_t	j_wait_commit;