[PATCH 03/15] tty: n_tty: use min3() in copy_from_read_buf()

From: Jiri Slaby (SUSE)
Date: Tue Sep 19 2023 - 04:52:14 EST


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@xxxxxxxxxx>
---
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