From: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
To: gregkh@linuxfoundation.org
Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
"Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Subject: [PATCH v2 04/14] tty: n_tty: use time_is_before_jiffies() in n_tty_receive_overrun()
Date: Sun, 27 Aug 2023 09:41:37 +0200 [thread overview]
Message-ID: <20230827074147.2287-5-jirislaby@kernel.org> (raw)
In-Reply-To: <20230827074147.2287-1-jirislaby@kernel.org>
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 7f9fee4cf7cf..c0b23e975877 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;
--
2.42.0
next prev parent reply other threads:[~2023-08-27 7:43 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-27 7:41 [PATCH v2 00/14] tty: n_tty: cleanup Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 01/14] tty: n_tty: make flow of n_tty_receive_buf_common() a bool Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 02/14] tty: n_tty: use output character directly Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 03/14] tty: n_tty: use 'num' for writes' counts Jiri Slaby (SUSE)
2023-08-27 7:41 ` Jiri Slaby (SUSE) [this message]
2023-08-27 7:41 ` [PATCH v2 05/14] tty: n_tty: make n_tty_data::num_overrun unsigned Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 06/14] tty: n_tty: use MASK() for masking out size bits Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 07/14] tty: n_tty: move canon handling to a separate function Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 08/14] tty: n_tty: move newline " Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 09/14] tty: n_tty: remove unsigned char casts from character constants Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 10/14] tty: n_tty: simplify chars_in_buffer() Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 11/14] tty: n_tty: use u8 for chars and flags Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 12/14] tty: n_tty: unify counts to size_t Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 13/14] tty: n_tty: extract ECHO_OP processing to a separate function Jiri Slaby (SUSE)
2023-08-27 7:41 ` [PATCH v2 14/14] tty: n_tty: deduplicate copy code in n_tty_receive_buf_real_raw() Jiri Slaby (SUSE)
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230827074147.2287-5-jirislaby@kernel.org \
--to=jirislaby@kernel.org \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-serial@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).