linux-serial.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
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 03/15] tty: n_tty: use min3() in copy_from_read_buf()
Date: Tue, 19 Sep 2023 10:51:44 +0200	[thread overview]
Message-ID: <20230919085156.1578-4-jirislaby@kernel.org> (raw)
In-Reply-To: <20230919085156.1578-1-jirislaby@kernel.org>

n is a minimum of:
* available chars in the ring buffer
* available chars in the ring buffer till the end of the ring buffer
* requested number (*nr)

We can use min3() for that instead of two min()s.

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 e917faa0b84c..6a112910c058 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1965,8 +1965,7 @@ static bool copy_from_read_buf(const struct tty_struct *tty, u8 **kbp,
 	size_t head = smp_load_acquire(&ldata->commit_head);
 	size_t tail = MASK(ldata->read_tail);
 
-	n = min(head - ldata->read_tail, N_TTY_BUF_SIZE - tail);
-	n = min(*nr, n);
+	n = min3(head - ldata->read_tail, N_TTY_BUF_SIZE - tail, *nr);
 	if (n) {
 		u8 *from = read_buf_addr(ldata, tail);
 		memcpy(*kbp, from, n);
-- 
2.42.0


  parent reply	other threads:[~2023-09-19  8:52 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-19  8:51 [PATCH 00/15] random tty fixes Jiri Slaby (SUSE)
2023-09-19  8:51 ` [PATCH 01/15] tty: n_tty: use 'retval' instead of 'c' Jiri Slaby (SUSE)
2023-09-19  8:51 ` [PATCH 02/15] tty: n_tty: rename and retype 'retval' in n_tty_ioctl() Jiri Slaby (SUSE)
2023-09-19  8:51 ` Jiri Slaby (SUSE) [this message]
2023-09-19  8:51 ` [PATCH 04/15] tty: n_tty: invert the condition in copy_from_read_buf() Jiri Slaby (SUSE)
2023-09-19  9:54   ` Ilpo Järvinen
2023-09-19 10:43     ` Jiri Slaby
2023-09-19  8:51 ` [PATCH 05/15] tty: n_tty: use do-while in n_tty_check_{,un}throttle() Jiri Slaby (SUSE)
2023-09-19  8:51 ` [PATCH 06/15] tty: switch tty_{,un}throttle_safe() to return a bool Jiri Slaby (SUSE)
2023-09-19  8:51 ` [PATCH 07/15] tty: invert return values of tty_{,un}throttle_safe() Jiri Slaby (SUSE)
2023-09-19  8:51 ` [PATCH 08/15] tty: fix up and plug in tty_ioctl kernel-doc Jiri Slaby (SUSE)
2023-09-19  8:51 ` [PATCH 09/15] tty: fix kernel-doc for functions in tty.h Jiri Slaby (SUSE)
2023-09-19 10:07   ` Ilpo Järvinen
2023-09-19 10:45     ` Jiri Slaby
2023-09-19 10:47       ` Jiri Slaby
2023-09-19 10:51         ` Ilpo Järvinen
2023-09-19  8:51 ` [PATCH 10/15] tty: stop using ndash in kernel-doc Jiri Slaby (SUSE)
2023-09-19  8:51 ` [PATCH 11/15] tty: tty_buffer: use bool for 'restart' in tty_buffer_unlock_exclusive() Jiri Slaby (SUSE)
2023-09-19  8:51 ` [PATCH 12/15] tty: convert THROTTLE constants into enum Jiri Slaby (SUSE)
2023-09-19 10:10   ` Ilpo Järvinen
2023-09-19 10:51     ` Jiri Slaby
2023-09-19  8:51 ` [PATCH 13/15] tty: early return from send_break() on TTY_DRIVER_HARDWARE_BREAK Jiri Slaby (SUSE)
2023-09-19  8:51 ` [PATCH 14/15] tty: don't check for signal_pending() in send_break() Jiri Slaby (SUSE)
2023-09-19 10:14   ` Ilpo Järvinen
2023-09-19  8:51 ` [PATCH 15/15] tty: use 'if' in send_break() instead of 'goto' Jiri Slaby (SUSE)
2023-09-19 10:17 ` [PATCH 00/15] random tty fixes Ilpo Järvinen
2023-09-19 10:21   ` Greg Kroah-Hartman
2023-09-19 10:53     ` Ilpo Järvinen

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=20230919085156.1578-4-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).