Date: Fri, 18 Apr 2008 18:22:41 GMT From: Sam Leffler <sam@FreeBSD.org> To: Perforce Change Reviews <perforce@freebsd.org> Subject: PERFORCE change 140218 for review Message-ID: <200804181822.m3IIMfeD060015@repoman.freebsd.org>
next in thread | raw e-mail | index | archive | help
http://perforce.freebsd.org/chv.cgi?CH=140218 Change 140218 by sam@sam_ebb on 2008/04/18 18:21:48 Eliminate holding the com lock over the ioctl callback to auto-up the parent device by deferring to a task. We mark the vap running so when the driver calls back to us through ieee80211_start_all we don't double count them in ic_nrunning. This eliminates the lock being held over the driver's init method which was problematic for drivers that must defer work (e.g. usb) Affected files ... .. //depot/projects/vap/sys/net80211/ieee80211_proto.c#28 edit .. //depot/projects/vap/sys/net80211/ieee80211_var.h#39 edit Differences ... ==== //depot/projects/vap/sys/net80211/ieee80211_proto.c#28 (text+ko) ==== @@ -37,6 +37,7 @@ #include <sys/param.h> #include <sys/kernel.h> #include <sys/systm.h> +#include <sys/taskqueue.h> #include <sys/socket.h> #include <sys/sockio.h> @@ -95,6 +96,7 @@ "WME_UPSD", }; +static void parent_up(void *, int); static int ieee80211_new_state_locked(struct ieee80211vap *, enum ieee80211_state, int); @@ -128,6 +130,8 @@ } ic->ic_protmode = IEEE80211_PROT_CTSONLY; + TASK_INIT(&ic->ic_parent_task, 0, parent_up, ifp); + ic->ic_wme.wme_hipri_switch_hysteresis = AGGRESSIVE_MODE_SWITCH_HYSTERESIS; @@ -1059,6 +1063,14 @@ } } +static void +parent_up(void *arg, int npending) +{ + struct ifnet *parent = arg; + + parent->if_ioctl(parent, SIOCSIFFLAGS, NULL); +} + /* * Start a vap running. If this is the first vap to be * set running on the underlying device then we @@ -1079,6 +1091,15 @@ if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) { /* + * Mark us running. Note that it's ok to do this first; + * if we need to bring the parent device up we defer that + * to avoid dropping the com lock. We expect the device + * to respond to being marked up by calling back into us + * through ieee80211_start_all at which point we'll come + * back in here and complete the work. + */ + ifp->if_drv_flags |= IFF_DRV_RUNNING; + /* * We are not running; if this we are the first vap * to be brought up auto-up the parent if necessary. */ @@ -1088,13 +1109,9 @@ IEEE80211_MSG_STATE | IEEE80211_MSG_DEBUG, "%s: up parent %s\n", __func__, parent->if_xname); parent->if_flags |= IFF_UP; - parent->if_ioctl(parent, SIOCSIFFLAGS, NULL); + taskqueue_enqueue(taskqueue_swi, &ic->ic_parent_task); + return; } - /* - * Mark us running. Note that we do this after - * bringing up the parent device to avoid recursion. - */ - ifp->if_drv_flags |= IFF_DRV_RUNNING; /* mark us running */ } /* * If the parent is up and running, then kick the @@ -1231,7 +1248,6 @@ /* * Stop all vap's running on a device. - * XXX not currently used */ void ieee80211_stop_all(struct ieee80211com *ic) @@ -1240,12 +1256,18 @@ struct ieee80211vap *vap; IEEE80211_LOCK(ic); + /* XXX why do we do this? */ /* XXX shouldn't touch driver state */ parent->if_drv_flags &= ~IFF_DRV_RUNNING; TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) { struct ifnet *ifp = vap->iv_ifp; - if (IFNET_IS_UP_RUNNING(ifp)) /* NB: avoid recursion */ + if (IFNET_IS_UP_RUNNING(ifp)) { /* NB: avoid recursion */ + /* + * NB: since parent is marked !RUNNING + * this won't drop com lock + */ ieee80211_stop_locked(vap); + } } IEEE80211_UNLOCK(ic); } ==== //depot/projects/vap/sys/net80211/ieee80211_var.h#39 (text+ko) ==== @@ -116,6 +116,7 @@ struct ifmedia ic_media; /* interface media config */ uint8_t ic_myaddr[IEEE80211_ADDR_LEN]; struct callout ic_inact; /* inactivity processing */ + struct task ic_parent_task; /* deferred parent processing */ uint32_t ic_flags; /* state flags */ uint32_t ic_flags_ext; /* extended state flags */
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200804181822.m3IIMfeD060015>