From: dlg <dlg@openbsd.org>
Date: Mon, 12 Jun 2017 23:20:10 +0000 (+0000)
Subject: have the timeout call if qstart via the serialiser isntead of directly
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=a6267f385ffe4a696c1087b00e37703f0499fd23;p=openbsd

have the timeout call if qstart via the serialiser isntead of directly

hfsc schedules a timeout to keep traffic moving if somethings has been
delayed an no other tx activity has occurred. that timeout was calling
(*ifp->if_qstart)(ifq) rather than ifq_start. the latter prevents
concurrent calls to if_qstart.

without this change bjorn ketelaars on misc@ was experiencing weird
pauses in traffic and lockups because the tx ring was corrupted
because re_start was run concurrently, once from the stack and once
from hfsc.

thanks to bjorn ketelaars for debugging, and mikeb@ for most of the
legwork in diagnosing the problem.
ok mikeb@
---

diff --git a/sys/net/hfsc.c b/sys/net/hfsc.c
index 8fddbe5d933..795e42f7f2a 100644
--- a/sys/net/hfsc.c
+++ b/sys/net/hfsc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: hfsc.c,v 1.39 2017/05/08 11:30:53 mikeb Exp $	*/
+/*	$OpenBSD: hfsc.c,v 1.40 2017/06/12 23:20:10 dlg Exp $	*/
 
 /*
  * Copyright (c) 2012-2013 Henning Brauer <henning@openbsd.org>
@@ -817,7 +817,7 @@ hfsc_deferred(void *arg)
 	KASSERT(HFSC_ENABLED(ifq));
 
 	if (!ifq_empty(ifq))
-		(*ifp->if_qstart)(ifq);
+		ifq_start(ifq);
 
 	hif = ifq->ifq_q;