[PATCH 4.14 31/37] tty: extract tty_flip_buffer_commit() from tty_flip_buffer_push()

Greg Kroah-Hartman
2022-07-27T16:28:34Z

From: Jiri Slaby <jslaby@suse.cz>

commit 716b10580283fda66f2b88140e3964f8a7f9da89 upstream.

We will need this new helper in the next patch.

Cc: Hillf Danton <hdanton@sina.com>
Cc: 一只狗 <chennbnbnb@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220707082558.9250-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/tty/tty_buffer.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -517,6 +517,15 @@ static void flush_to_ldisc(struct work_s

}

+static inline void tty_flip_buffer_commit(struct tty_buffer *tail)
+{
+ /*
+ * Paired w/ acquire in flush_to_ldisc(); ensures flush_to_ldisc() sees
+ * buffer data.
+ */
+ smp_store_release(&tail->commit, tail->used);
+}
+
/**
* tty_flip_buffer_push - terminal
* @port: tty port to push
@@ -532,11 +541,7 @@ void tty_flip_buffer_push(struct tty_por
{
struct tty_bufhead *buf = &port->buf;

- /*
- * Paired w/ acquire in flush_to_ldisc(); ensures flush_to_ldisc() sees
- * buffer data.
- */
- smp_store_release(&buf->tail->commit, buf->tail->used);
+ tty_flip_buffer_commit(buf->tail);
queue_work(system_unbound_wq, &buf->work);
}
EXPORT_SYMBOL(tty_flip_buffer_push);