From eb68e3cd5655f3c8b22efce511fc5a056aa1f1a7 Mon Sep 17 00:00:00 2001
From: Alexander Motin <mav@FreeBSD.org>
Date: Tue, 29 Nov 2022 12:26:03 -0500
Subject: [PATCH] Micro-optimize zrl_remove()

atomic_dec_32() should be a bit lighter than atomic_dec_32_nv().

Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Closes #14200
---
 module/zfs/zrlock.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/module/zfs/zrlock.c b/module/zfs/zrlock.c
index a4def60536..8b6755bc93 100644
--- a/module/zfs/zrlock.c
+++ b/module/zfs/zrlock.c
@@ -106,16 +106,16 @@ zrl_add_impl(zrlock_t *zrl, const char *zc)
 void
 zrl_remove(zrlock_t *zrl)
 {
-	uint32_t n;
-
 #ifdef	ZFS_DEBUG
 	if (zrl->zr_owner == curthread) {
 		zrl->zr_owner = NULL;
 		zrl->zr_caller = NULL;
 	}
+	int32_t n = atomic_dec_32_nv((uint32_t *)&zrl->zr_refcount);
+	ASSERT3S(n, >=, 0);
+#else
+	atomic_dec_32((uint32_t *)&zrl->zr_refcount);
 #endif
-	n = atomic_dec_32_nv((uint32_t *)&zrl->zr_refcount);
-	ASSERT3S((int32_t)n, >=, 0);
 }
 
 int