Commit 34f8f0a5 authored Dec 13, 2006 by Ralf Baechle Committed by Linus Torvalds Dec 13, 2006

[PATCH] tty: remove useless memory barrier



I don't see why there is a memory barrier in copy_from_read_buf() at all.
Even if it was useful spin_unlock_irqrestore implies a barrier.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent cd861280

drivers/char/n_tty.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -1151,7 +1151,6 @@ static int copy_from_read_buf(struct tty_struct *tty,
		n = min(*nr, n);
		spin_unlock_irqrestore(&tty->read_lock, flags);
		if (n) {
		mb();
		retval = copy_to_user(*b, &tty->read_buf[tty->read_tail], n);
		n -= retval;
		spin_lock_irqsave(&tty->read_lock, flags);