[tip: locking/core] futex: Use atomic64_inc_return() in get_inode_sequence_number()

From: tip-bot2 for Uros Bizjak
Date: Thu Oct 17 2024 - 16:11:03 EST


The following commit has been merged into the locking/core branch of tip:

Commit-ID: 19298f48694987fac843261c84e24834c255b451
Gitweb: https://git.kernel.org/tip/19298f48694987fac843261c84e24834c255b451
Author: Uros Bizjak <ubizjak@xxxxxxxxx>
AuthorDate: Thu, 10 Oct 2024 09:10:04 +02:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Thu, 17 Oct 2024 22:02:27 +02:00

futex: Use atomic64_inc_return() in get_inode_sequence_number()

Use atomic64_inc_return(&ref) instead of atomic64_add_return(1, &ref)
to use optimized implementation and ease register pressure around
the primitive for targets that implement optimized variant.

Signed-off-by: Uros Bizjak <ubizjak@xxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: André Almeida <andrealmeid@xxxxxxxxxx>
Link: https://lore.kernel.org/all/20241010071023.21913-1-ubizjak@xxxxxxxxx

---
kernel/futex/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/futex/core.c b/kernel/futex/core.c
index 136768a..3146730 100644
--- a/kernel/futex/core.c
+++ b/kernel/futex/core.c
@@ -181,7 +181,7 @@ static u64 get_inode_sequence_number(struct inode *inode)
return old;

for (;;) {
- u64 new = atomic64_add_return(1, &i_seq);
+ u64 new = atomic64_inc_return(&i_seq);
if (WARN_ON_ONCE(!new))
continue;