diff options
| -rw-r--r-- | drivers/tty/tty_buffer.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c index b3a5e33948c1..a660ab181cca 100644 --- a/drivers/tty/tty_buffer.c +++ b/drivers/tty/tty_buffer.c @@ -293,7 +293,10 @@ static int __tty_buffer_request_room(struct tty_port *port, size_t size, if (n != NULL) { n->flags = flags; buf->tail = n; - b->commit = b->used; + /* paired w/ acquire in flush_to_ldisc(); ensures + * flush_to_ldisc() sees buffer data. + */ + smp_store_release(&b->commit, b->used); /* paired w/ acquire in flush_to_ldisc(); ensures the * latest commit value can be read before the head is * advanced to the next buffer @@ -396,7 +399,10 @@ void tty_schedule_flip(struct tty_port *port) { struct tty_bufhead *buf = &port->buf; - buf->tail->commit = buf->tail->used; + /* paired w/ acquire in flush_to_ldisc(); ensures + * flush_to_ldisc() sees buffer data. + */ + smp_store_release(&buf->tail->commit, buf->tail->used); schedule_work(&buf->work); } EXPORT_SYMBOL(tty_schedule_flip); @@ -494,7 +500,10 @@ static void flush_to_ldisc(struct work_struct *work) * is advancing to the next buffer */ next = smp_load_acquire(&head->next); - count = head->commit - head->read; + /* paired w/ release in __tty_buffer_request_room() or in + * tty_buffer_flush(); ensures we see the committed buffer data + */ + count = smp_load_acquire(&head->commit) - head->read; if (!count) { if (next == NULL) { check_other_closed(tty); |