From 6215416f96d04fd1a1b0e14e2670c208f0acc34c Mon Sep 17 00:00:00 2001 From: David Gwynne Date: Wed, 25 Nov 2015 03:10:01 +0000 Subject: replace IFF_OACTIVE manipulation with mpsafe operations. there are two things shared between the network stack and drivers in the send path: the send queue and the IFF_OACTIVE flag. the send queue is now protected by a mutex. this diff makes the oactive functionality mpsafe too. IFF_OACTIVE is part of if_flags. there are two problems with that. firstly, if_flags is a short and we dont have any MI atomic operations to manipulate a short. secondly, while we could make the IFF_OACTIVE operates mpsafe, all changes to other flags would have to be made safe at the same time, otherwise a read-modify-write cycle on their updates could clobber the oactive change. instead, this moves the oactive mark into struct ifqueue and provides an API for changing it. there's ifq_set_oactive, ifq_clr_oactive, and ifq_is_oactive. these are modelled on ifsq_set_oactive, ifsq_clr_oactive, and ifsq_is_oactive in dragonflybsd. this diff includes changes to all the drivers manipulating IFF_OACTIVE to now use the ifsq_{set,clr_is}_oactive API too. ok kettenis@ mpi@ jmatthew@ deraadt@ --- sys/dev/usb/if_udav.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'sys/dev/usb/if_udav.c') diff --git a/sys/dev/usb/if_udav.c b/sys/dev/usb/if_udav.c index 8b577c0b750..f3b378f2bbc 100644 --- a/sys/dev/usb/if_udav.c +++ b/sys/dev/usb/if_udav.c @@ -1,4 +1,4 @@ -/* $OpenBSD: if_udav.c,v 1.76 2015/11/24 17:11:40 mpi Exp $ */ +/* $OpenBSD: if_udav.c,v 1.77 2015/11/25 03:10:00 dlg Exp $ */ /* $NetBSD: if_udav.c,v 1.3 2004/04/23 17:25:25 itojun Exp $ */ /* $nabe: if_udav.c,v 1.3 2003/08/21 16:57:19 nabe Exp $ */ /* @@ -646,7 +646,7 @@ udav_init(struct ifnet *ifp) } ifp->if_flags |= IFF_RUNNING; - ifp->if_flags &= ~IFF_OACTIVE; + ifq_clr_oactive(&ifp->if_snd); splx(s); @@ -913,7 +913,7 @@ udav_start(struct ifnet *ifp) if (!sc->sc_link) return; - if (ifp->if_flags & IFF_OACTIVE) + if (ifq_is_oactive(&ifp->if_snd)) return; m_head = ifq_deq_begin(&ifp->if_snd); @@ -922,7 +922,7 @@ udav_start(struct ifnet *ifp) if (udav_send(sc, m_head, 0)) { ifq_deq_rollback(&ifp->if_snd, m_head); - ifp->if_flags |= IFF_OACTIVE; + ifq_set_oactive(&ifp->if_snd); return; } @@ -933,7 +933,7 @@ udav_start(struct ifnet *ifp) bpf_mtap(ifp->if_bpf, m_head, BPF_DIRECTION_OUT); #endif - ifp->if_flags |= IFF_OACTIVE; + ifq_set_oactive(&ifp->if_snd); /* Set a timeout in case the chip goes out to lunch. */ ifp->if_timer = 5; @@ -1007,7 +1007,7 @@ udav_txeof(struct usbd_xfer *xfer, void *priv, usbd_status status) DPRINTF(("%s: %s: enter\n", sc->sc_dev.dv_xname, __func__)); ifp->if_timer = 0; - ifp->if_flags &= ~IFF_OACTIVE; + ifq_clr_oactive(&ifp->if_snd); if (status != USBD_NORMAL_COMPLETION) { if (status == USBD_NOT_STARTED || status == USBD_CANCELLED) { @@ -1220,7 +1220,8 @@ udav_stop(struct ifnet *ifp, int disable) DPRINTF(("%s: %s: enter\n", sc->sc_dev.dv_xname, __func__)); ifp->if_timer = 0; - ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE); + ifp->if_flags &= ~IFF_RUNNING; + ifq_clr_oactive(&ifp->if_snd); udav_reset(sc); -- cgit v1.2.3