svn commit: r213711 - head/sys/dev/bge

[Pyun YongHyeon]

Author: yongari
Date: Mon Oct 11 23:07:12 2010
New Revision: 213711
URL: http://svn.freebsd.org/changeset/base/213711

Log:
  The IFF_DRV_RUNNING flag is set at the end of bge_init_locked. But
  before setting the flag, interrupt was already enabled such that
  interrupt handler could be run before setting IFF_DRV_RUNNING flag.
  This can lose initial link state change interrupt which in turn
  make bge(4) think that it still does not have valid link. Fix this
  race by protecting the taskqueue with a driver lock.
  While I'm here move reenabling interrupt code after handling of link
  state chage.
  
  Reviewed by:	davidch

Modified:
  head/sys/dev/bge/if_bge.c

Modified: head/sys/dev/bge/if_bge.c
==============================================================================
--- head/sys/dev/bge/if_bge.c	Mon Oct 11 22:56:23 2010	(r213710)
+++ head/sys/dev/bge/if_bge.c	Mon Oct 11 23:07:12 2010	(r213711)
@@ -3629,8 +3629,11 @@ bge_intr_task(void *arg, int pending)
 	sc = (struct bge_softc *)arg;
 	ifp = sc->bge_ifp;
 
-	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
+	BGE_LOCK(sc);
+	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
+		BGE_UNLOCK(sc);
 		return;
+	}
 
 	/* Get updated status block. */
 	bus_dmamap_sync(sc->bge_cdata.bge_status_tag,
@@ -3645,26 +3648,27 @@ bge_intr_task(void *arg, int pending)
 	bus_dmamap_sync(sc->bge_cdata.bge_status_tag,
 	    sc->bge_cdata.bge_status_map,
 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
+
+	if ((status & BGE_STATFLAG_LINKSTATE_CHANGED) != 0)
+		bge_link_upd(sc);
+
 	/* Let controller work. */
 	bge_writembx(sc, BGE_MBX_IRQ0_LO, 0);
 
-	if ((status & BGE_STATFLAG_LINKSTATE_CHANGED) != 0) {
-		BGE_LOCK(sc);
-		bge_link_upd(sc);
-		BGE_UNLOCK(sc);
-	}
-	if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
+	if (ifp->if_drv_flags & IFF_DRV_RUNNING &&
+	    sc->bge_rx_saved_considx != rx_prod) {
 		/* Check RX return ring producer/consumer. */
+		BGE_UNLOCK(sc);
 		bge_rxeof(sc, rx_prod, 0);
+		BGE_LOCK(sc);
 	}
 	if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
-		BGE_LOCK(sc);
 		/* Check TX ring producer/consumer. */
 		bge_txeof(sc, tx_cons);
 	    	if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
 			bge_start_locked(ifp);
-		BGE_UNLOCK(sc);
 	}
+	BGE_UNLOCK(sc);
 }
 
 static void