linux-kernel - [PATCH 03/15] tty: n_tty: use min3() in copy_from_read

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Message-ID: <20230919085156.1578-4-jirislaby@kernel.org>
Date:   Tue, 19 Sep 2023 10:51:44 +0200
From:   "Jiri Slaby (SUSE)" <jirislaby@...nel.org>
To:     gregkh@...uxfoundation.org
Cc:     linux-serial@...r.kernel.org, linux-kernel@...r.kernel.org,
        "Jiri Slaby (SUSE)" <jirislaby@...nel.org>
Subject: [PATCH 03/15] tty: n_tty: use min3() in copy_from_read_buf()

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@...nel.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