lkml.org 
[lkml]   [2023]   [Aug]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 04/14] tty: n_tty: use time_is_before_jiffies() in n_tty_receive_overrun()
Date
The jiffies tests in n_tty_receive_overrun() are simplified ratelimiting
(without locking). We could use struct ratelimit_state and the helpers,
but to me, it occurs to be too complex for this use case.

But the code currently tests both if the time passed (the first
time_after()) and if jiffies wrapped around (the second time_after()).
time_is_before_jiffies() takes care of both, provided overrun_time is
initialized at the allocation time.

So switch to time_is_before_jiffies(), the same what ratelimiting does.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
---
drivers/tty/n_tty.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index e293d87b5362..996cad23e385 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1173,8 +1173,7 @@ static void n_tty_receive_overrun(const struct tty_struct *tty)
struct n_tty_data *ldata = tty->disc_data;

ldata->num_overrun++;
- if (time_after(jiffies, ldata->overrun_time + HZ) ||
- time_after(ldata->overrun_time, jiffies)) {
+ if (time_is_before_jiffies(ldata->overrun_time + HZ)) {
tty_warn(tty, "%d input overrun(s)\n", ldata->num_overrun);
ldata->overrun_time = jiffies;
ldata->num_overrun = 0;
--
2.41.0
\
 
 \ /
  Last update: 2023-08-16 13:02    [W:0.097 / U:2.900 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site