From 961655f915028fd850429f9ab41ea1c2b4ed1433 Mon Sep 17 00:00:00 2001
From: Taylor R Campbell <riastradh@NetBSD.org>
Date: Thu, 31 Mar 2022 01:21:08 +0000
Subject: [PATCH 16/49] audio(4): Use membar_acquire, not membar_enter.

Cheaper and adequate to make an atomic_swap into a load-acquire.
---
 sys/dev/audio/audio.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/sys/dev/audio/audio.c b/sys/dev/audio/audio.c
index 424762986e1b..9a59f1873a12 100644
--- a/sys/dev/audio/audio.c
+++ b/sys/dev/audio/audio.c
@@ -316,7 +316,7 @@ audio_mlog_flush(void)
 	/* Nothing to do if already in use ? */
 	if (atomic_swap_32(&mlog_inuse, 1) == 1)
 		return;
-	membar_enter();
+	membar_acquire();
 
 	int rpage = mlog_wpage;
 	mlog_wpage ^= 1;
@@ -353,7 +353,7 @@ audio_mlog_printf(const char *fmt, ...)
 		mlog_drop++;
 		return;
 	}
-	membar_enter();
+	membar_acquire();
 
 	va_start(ap, fmt);
 	len = vsnprintf(
@@ -1684,7 +1684,7 @@ audio_track_lock_tryenter(audio_track_t *track)
 
 	if (atomic_swap_uint(&track->lock, 1) != 0)
 		return false;
-	membar_enter();
+	membar_acquire();
 	return true;
 }