gigaset: prune use of tty_buffer_request_room

commit 873a69a358a6b393fd8d9d92e193ec8895cac4d7 upstream.

Calling tty_buffer_request_room() before tty_insert_flip_string()
is unnecessary, costs CPU and for big buffers can mess up the
multi-page allocation avoidance.

Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Acked-by: Karsten Keil <keil@b1-systems.de>
CC: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/isdn/gigaset/interface.c b/drivers/isdn/gigaset/interface.c
index 6a8e1384e7bd09b6441ef6a27eaed5c497f31061..b3065b8b24568674ae7b5c64504f6d9a5e3ca360 100644 (file)
--- a/drivers/isdn/gigaset/interface.c
+++ b/drivers/isdn/gigaset/interface.c
@@ -635,7 +635,6 @@ void gigaset_if_receive(struct cardstate *cs,
        if ((tty = cs->tty) == NULL)
                gig_dbg(DEBUG_ANY, "receive on closed device");
        else {
-               tty_buffer_request_room(tty, len);
                tty_insert_flip_string(tty, buffer, len);
                tty_flip_buffer_push(tty);
        }