ext4: remove unaligned AIO warning printk

Although I put this in, I now think it was a bad decision.  For most
users, there is very little to be done in this case.  They get the
message, once per day, with no real context or proposed action.  TBH,
it generates support calls when it probably does not need to; the
message sounds more dire than the situation really is.

Just nuke it.  Normal investigation via blktrace or whatnot can
reveal poor IO patterns if bad performance is encountered.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

fs/ext4/file.c

@@ -108,14 +108,6 @@ ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
 
 	/* Unaligned direct AIO must be serialized; see comment above */
 	if (unaligned_aio) {
-		static unsigned long unaligned_warn_time;
-
-		/* Warn about this once per day */
-		if (printk_timed_ratelimit(&unaligned_warn_time, 60*60*24*HZ))
-			ext4_msg(inode->i_sb, KERN_WARNING,
-				 "Unaligned AIO/DIO on inode %ld by %s; "
-				 "performance will be poor.",
-				 inode->i_ino, current->comm);
 		mutex_lock(ext4_aio_mutex(inode));
 		ext4_unwritten_wait(inode);
 	}