[PATCH] remove active field from tty buffer structure

Remove 'active' field from tty buffer structure.  This was added in 2.6.16
as part of a patch to make the new tty buffering SMP safe.  This field is
unnecessary with the more intelligently written flush_to_ldisc that adds
receive_room handling.

Removing this field reverts to simpler logic where the tail buffer is
always the 'active' buffer, which should not be freed by flush_to_ldisc.
(active == buffer being filled with new data)

The result is simpler, smaller, and faster tty buffer code.

Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 3 deletions

diff --git a/include/linux/kbd_kern.h b/include/linux/kbd_kern.h
index 4eb851ece080..efe0ee4cc80b 100644
--- a/include/linux/kbd_kern.h
+++ b/include/linux/kbd_kern.h
@@ -155,10 +155,8 @@ static inline void con_schedule_flip(struct tty_struct *t)
 {
         unsigned long flags;
         spin_lock_irqsave(&t->buf.lock, flags);
-        if (t->buf.tail != NULL) {
-                t->buf.tail->active = 0;
+        if (t->buf.tail != NULL)
                 t->buf.tail->commit = t->buf.tail->used;
-        }
         spin_unlock_irqrestore(&t->buf.lock, flags);
         schedule_work(&t->buf.work);
 }