[PATCH tty-next 5/7] n_tty: Refactor input_available_p() by call site

From: Peter Hurley
Date: Fri Nov 22 2013 - 11:01:01 EST


Distinguish if caller is n_tty_poll() or n_tty_read(), and
set the read/wakeup threshold accordingly.

Signed-off-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
---
drivers/tty/n_tty.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 9298b68..8f2356e 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1878,14 +1878,15 @@ static int n_tty_open(struct tty_struct *tty)
return 0;
}

-static inline int input_available_p(struct tty_struct *tty, int amt)
+static inline int input_available_p(struct tty_struct *tty, int poll)
{
struct n_tty_data *ldata = tty->disc_data;
+ int amt = poll && !TIME_CHAR(tty) ? MIN_CHAR(tty) : 1;

if (ldata->icanon && !L_EXTPROC(tty)) {
if (ldata->canon_head != ldata->read_tail)
return 1;
- } else if (read_cnt(ldata) >= (amt ? amt : 1))
+ } else if (read_cnt(ldata) >= amt)
return 1;

return 0;
@@ -2384,7 +2385,7 @@ static unsigned int n_tty_poll(struct tty_struct *tty, struct file *file,

poll_wait(file, &tty->read_wait, wait);
poll_wait(file, &tty->write_wait, wait);
- if (input_available_p(tty, TIME_CHAR(tty) ? 0 : MIN_CHAR(tty)))
+ if (input_available_p(tty, 1))
mask |= POLLIN | POLLRDNORM;
else if (ldata->icanon)
n_tty_set_room(tty);
--
1.8.1.2

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