From c5f976950fe893e18da75600b18e616fb29f0d4c Mon Sep 17 00:00:00 2001
From: dlg <dlg@openbsd.org>
Date: Tue, 30 May 2023 23:55:42 +0000
Subject: [PATCH] add net_tq_barriers

this waits once for something to end in all the net tqs.

ok claudio@
---
 sys/net/if.c | 18 +++++++++++++++++-
 sys/net/if.h |  3 ++-
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/sys/net/if.c b/sys/net/if.c
index ae1069b405a..36c52330e35 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.c,v 1.697 2023/05/16 14:32:54 jan Exp $	*/
+/*	$OpenBSD: if.c,v 1.698 2023/05/30 23:55:42 dlg Exp $	*/
 /*	$NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $	*/
 
 /*
@@ -3476,3 +3476,19 @@ net_tq(unsigned int ifindex)
 
 	return (sn->sn_taskq);
 }
+
+void
+net_tq_barriers(const char *wmesg)
+{
+	struct task barriers[NET_TASKQ];
+	struct refcnt r = REFCNT_INITIALIZER();
+	int i;
+
+	for (i = 0; i < nitems(barriers); i++) {
+		task_set(&barriers[i], (void (*)(void *))refcnt_rele_wake, &r);
+		refcnt_take(&r);
+		task_add(softnets[i].sn_taskq, &barriers[i]);
+	}
+ 
+	refcnt_finalize(&r, wmesg);
+}
diff --git a/sys/net/if.h b/sys/net/if.h
index 189ce873c12..fdf04c50715 100644
--- a/sys/net/if.h
+++ b/sys/net/if.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.h,v 1.213 2023/05/16 14:32:54 jan Exp $	*/
+/*	$OpenBSD: if.h,v 1.214 2023/05/30 23:55:42 dlg Exp $	*/
 /*	$NetBSD: if.h,v 1.23 1996/05/07 02:40:27 thorpej Exp $	*/
 
 /*
@@ -560,6 +560,7 @@ int	if_congested(void);
 __dead void	unhandled_af(int);
 int	if_setlladdr(struct ifnet *, const uint8_t *);
 struct taskq * net_tq(unsigned int);
+void	net_tq_barriers(const char *);
 
 #endif /* _KERNEL */
 
-- 
2.20.1