tty: extract tty_flip_buffer_commit() from tty_flip_buffer_push()

BugLink: https://bugs.launchpad.net/bugs/1988479
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>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index d63c1f6c7ef45021bd93c92371d99fdc9f570c70..76fb600c1f7933777fcd3eda77a272904b3ee68d 100644 (file)
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -533,6 +533,15 @@ static void flush_to_ldisc(struct work_struct *work)
 
 }
 
+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
@@ -548,11 +557,7 @@ void tty_flip_buffer_push(struct tty_port *port)
 {
        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);