Preparation for re-iplementing low-latency port support. Replace queue_work
and schedule_work with tty_buffer_queue_work, and calls to flush_work with
tty_buffer_flush_work. cancel_work_sync are replaced by tty_buffer_flush_work
as well, because kthread workqueues don't have a method of cancellation other
than to flush. flush could potentially take longer, but we would already delay
if the callback were in progress. Since it's only used from the release /
destroy path, the difference should be negligible.
Signed-off-by: Steven Walter <stevenrwalter@xxxxxxxxx>
---
drivers/tty/n_tty.c | 2 +-
drivers/tty/tty_buffer.c | 19 ++++++++++++++++---
drivers/tty/tty_io.c | 2 +-
drivers/tty/tty_ldisc.c | 4 ++--
drivers/tty/tty_port.c | 2 +-
include/linux/tty.h | 2 ++
6 files changed, 23 insertions(+), 8 deletions(-)
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 47ca0f3..c3869a5 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -214,7 +214,7 @@ static void n_tty_set_room(struct tty_struct *tty)
*/
WARN_RATELIMIT(test_bit(TTY_LDISC_HALTED, &tty->flags),
"scheduling buffer work for halted ldisc\n");
- queue_work(system_unbound_wq, &tty->port->buf.work);
+ tty_buffer_queue_work(tty->port);
}
}
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index 143deb6..ed7b5c8 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -72,7 +72,7 @@ void tty_buffer_unlock_exclusive(struct tty_port *port)
atomic_dec(&buf->priority);
mutex_unlock(&buf->lock);
if (restart)
- queue_work(system_unbound_wq, &buf->work);
+ tty_buffer_queue_work(port);
}
EXPORT_SYMBOL_GPL(tty_buffer_unlock_exclusive);
@@ -364,7 +364,7 @@ void tty_schedule_flip(struct tty_port *port)
struct tty_bufhead *buf = &port->buf;
buf->tail->commit = buf->tail->used;
- schedule_work(&buf->work);
+ tty_buffer_queue_work(port);
}
EXPORT_SYMBOL(tty_schedule_flip);
@@ -492,7 +492,7 @@ static void flush_to_ldisc(struct work_struct *work)
*/
void tty_flush_to_ldisc(struct tty_struct *tty)
{
- flush_work(&tty->port->buf.work);
+ tty_buffer_flush_work(tty->port);
}
/**
@@ -520,6 +520,19 @@ EXPORT_SYMBOL(tty_flip_buffer_push);
* Must be called before the other tty buffer functions are used.
*/
+
+void tty_buffer_queue_work(struct tty_port *port)
+{
+ struct tty_bufhead *buf = &port->buf;
+ schedule_work(&buf->work);
+}
+
+void tty_buffer_flush_work(struct tty_port *port)
+{
+ struct tty_bufhead *buf = &port->buf;
+ flush_work(&buf->work);
+}
+
void tty_buffer_init(struct tty_port *port)
{
struct tty_bufhead *buf = &port->buf;
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 0508a1d..c288473 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -1633,7 +1633,7 @@ static void release_tty(struct tty_struct *tty, int idx)
tty->port->itty = NULL;
if (tty->link)
tty->link->port->itty = NULL;
- cancel_work_sync(&tty->port->buf.work);
+ tty_buffer_flush_work(tty->port);
if (tty->link)
tty_kref_put(tty->link);
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 2d822aa..982f082 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -584,9 +584,9 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc)
/* Restart the work queue in case no characters kick it off. Safe if
already running */
- schedule_work(&tty->port->buf.work);
+ tty_buffer_queue_work(tty->port);
if (o_tty)
- schedule_work(&o_tty->port->buf.work);
+ tty_buffer_queue_work(o_tty->port);
tty_unlock(tty);
return retval;
diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 1b93357..d041323 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -131,7 +131,7 @@ EXPORT_SYMBOL(tty_port_free_xmit_buf);
*/
void tty_port_destroy(struct tty_port *port)
{
- cancel_work_sync(&port->buf.work);
+ tty_buffer_flush_work(port);
tty_buffer_free_all(port);
}
EXPORT_SYMBOL(tty_port_destroy);
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 5171ef8..7bad787 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -446,6 +446,8 @@ extern void tty_flush_to_ldisc(struct tty_struct *tty);
extern void tty_buffer_free_all(struct tty_port *port);
extern void tty_buffer_flush(struct tty_struct *tty);
extern void tty_buffer_init(struct tty_port *port);
+extern void tty_buffer_queue_work(struct tty_port *port);
+extern void tty_buffer_flush_work(struct tty_port *port);
extern speed_t tty_termios_baud_rate(struct ktermios *termios);
extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
extern void tty_termios_encode_baud_rate(struct ktermios *termios,
--
1.9.1
--
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