From 3600006e8ca208df97ab85d298f0258cf7e98abc Mon Sep 17 00:00:00 2001 From: bms Date: Fri, 9 Jul 2004 00:17:14 +0000 Subject: Further locking improvements for vr(4): - Add *_locked() entry points as needed to avoid unnecessary lock thrashing. - Use these entry points wisely. - Only acquire the lock once when servicing an interrupt. - Check 'suspended' on interrupt to avoid racing detach. - Correct a mis-spelled comment. - Don't take the lock in vr_reset() to avoid lock thrashing in attach. - Comment this. Reviewed by: -net (silence) --- sys/pci/if_vr.c | 115 +++++++++++++++++++++++++++++++++----------------------- 1 file changed, 69 insertions(+), 46 deletions(-) (limited to 'sys/pci') diff --git a/sys/pci/if_vr.c b/sys/pci/if_vr.c index 85569f6..945388c 100644 --- a/sys/pci/if_vr.c +++ b/sys/pci/if_vr.c @@ -142,8 +142,10 @@ static void vr_txeof (struct vr_softc *); static void vr_tick (void *); static void vr_intr (void *); static void vr_start (struct ifnet *); +static void vr_start_locked (struct ifnet *); static int vr_ioctl (struct ifnet *, u_long, caddr_t); static void vr_init (void *); +static void vr_init_locked (struct vr_softc *); static void vr_stop (struct vr_softc *); static void vr_watchdog (struct ifnet *); static void vr_shutdown (device_t); @@ -587,7 +589,7 @@ vr_reset(struct vr_softc *sc) { register int i; - VR_LOCK_ASSERT(sc); + /*VR_LOCK_ASSERT(sc);*/ /* XXX: Called during detach w/o lock. */ VR_SETBIT16(sc, VR_COMMAND, VR_CMD_RESET); @@ -688,9 +690,7 @@ vr_attach(dev) VR_CLRBIT(sc, VR_STICKHW, (VR_STICKHW_DS0|VR_STICKHW_DS1)); /* Reset the adapter. */ - VR_LOCK(sc); vr_reset(sc); - VR_UNLOCK(sc); /* * Turn on bit2 (MIION) in PCI configuration register 0x53 during @@ -755,6 +755,8 @@ vr_attach(dev) /* Call MI attach routine. */ ether_ifattach(ifp, eaddr); + sc->suspended = 0; + /* Hook interrupt last to avoid having to lock softc */ error = bus_setup_intr(dev, sc->vr_irq, INTR_TYPE_NET | INTR_MPSAFE, vr_intr, sc, &sc->vr_intrhand); @@ -789,6 +791,8 @@ vr_detach(device_t dev) VR_LOCK(sc); + sc->suspended = 1; + /* These should only be active if attach succeeded */ if (device_is_attached(dev)) { vr_stop(sc); @@ -1117,7 +1121,7 @@ vr_tick(void *xsc) printf("vr%d: restarting\n", sc->vr_unit); vr_stop(sc); vr_reset(sc); - vr_init(sc); + vr_init_locked(sc); sc->vr_flags &= ~VR_F_RESTART; } @@ -1130,6 +1134,7 @@ vr_tick(void *xsc) #ifdef DEVICE_POLLING static poll_handler_t vr_poll; +static poll_handler_t vr_poll_locked; static void vr_poll(struct ifnet *ifp, enum poll_cmd cmd, int count) @@ -1137,6 +1142,16 @@ vr_poll(struct ifnet *ifp, enum poll_cmd cmd, int count) struct vr_softc *sc = ifp->if_softc; VR_LOCK(sc); + vr_poll_locked(ifp, cmd, count); + VR_UNLOCK(sc); +} + +static void +vr_poll_locked(struct ifnet *ifp, enum poll_cmd cmd, int count) +{ + struct vr_softc *sc = ifp->if_softc; + + VR_LOCK_ASSERT(sc); if (!(ifp->if_capenable & IFCAP_POLLING)) { ether_poll_deregister(ifp); @@ -1146,17 +1161,14 @@ vr_poll(struct ifnet *ifp, enum poll_cmd cmd, int count) if (cmd == POLL_DEREGISTER) { /* Final call, enable interrupts. */ CSR_WRITE_2(sc, VR_IMR, VR_INTRS); - goto done; + return; } sc->rxcycles = count; vr_rxeof(sc); vr_txeof(sc); - if (ifp->if_snd.ifq_head != NULL) { - VR_UNLOCK(sc); - vr_start(ifp); - VR_LOCK(sc); - } + if (ifp->if_snd.ifq_head != NULL) + vr_start_locked(ifp); if (cmd == POLL_AND_CHECK_STATUS) { uint16_t status; @@ -1167,7 +1179,7 @@ vr_poll(struct ifnet *ifp, enum poll_cmd cmd, int count) CSR_WRITE_2(sc, VR_ISR, status); if ((status & VR_INTRS) == 0) - goto done; + return; if (status & VR_ISR_RX_DROPPED) { printf("vr%d: rx packet lost\n", sc->vr_unit); @@ -1191,8 +1203,7 @@ vr_poll(struct ifnet *ifp, enum poll_cmd cmd, int count) if ((status & VR_ISR_BUSERR) || (status & VR_ISR_TX_UNDERRUN)) { vr_reset(sc); - VR_UNLOCK(sc); - vr_init(sc); + vr_init_locked(sc); return; } @@ -1206,8 +1217,6 @@ vr_poll(struct ifnet *ifp, enum poll_cmd cmd, int count) } } } -done: - VR_UNLOCK(sc); } #endif /* DEVICE_POLLING */ @@ -1219,26 +1228,27 @@ vr_intr(void *arg) uint16_t status; VR_LOCK(sc); + + if (sc->suspended) + goto done_locked; + #ifdef DEVICE_POLLING - if (ifp->if_flags & IFF_POLLING) { - VR_UNLOCK(sc); - return; - } + if (ifp->if_flags & IFF_POLLING) + goto done_locked; + if ((ifp->if_capenable & IFCAP_POLLING) && ether_poll_register(vr_poll, ifp)) { /* OK, disable interrupts. */ CSR_WRITE_2(sc, VR_IMR, 0x0000); - VR_UNLOCK(sc); - vr_poll(ifp, 0, 1); - return; + vr_poll_locked(ifp, 0, 1); + goto done_locked; } #endif /* DEVICE_POLLING */ - /* Supress unwanted interrupts. */ + /* Suppress unwanted interrupts. */ if (!(ifp->if_flags & IFF_UP)) { vr_stop(sc); - VR_UNLOCK(sc); - return; + goto done_locked; } /* Disable interrupts. */ @@ -1276,9 +1286,7 @@ vr_intr(void *arg) if ((status & VR_ISR_BUSERR) || (status & VR_ISR_TX_UNDERRUN)) { vr_reset(sc); - VR_UNLOCK(sc); - vr_init(sc); - VR_LOCK(sc); + vr_init_locked(sc); break; } @@ -1301,10 +1309,12 @@ vr_intr(void *arg) /* Re-enable interrupts. */ CSR_WRITE_2(sc, VR_IMR, VR_INTRS); - VR_UNLOCK(sc); if (_IF_QLEN(&ifp->if_snd) != 0) - vr_start(ifp); + vr_start_locked(ifp); + +done_locked: + VR_UNLOCK(sc); } /* @@ -1361,14 +1371,22 @@ static void vr_start(struct ifnet *ifp) { struct vr_softc *sc = ifp->if_softc; + + VR_LOCK(sc); + vr_start_locked(ifp); + VR_UNLOCK(sc); +} + +static void +vr_start_locked(struct ifnet *ifp) +{ + struct vr_softc *sc = ifp->if_softc; struct mbuf *m_head; struct vr_chain *cur_tx; if (ifp->if_flags & IFF_OACTIVE) return; - VR_LOCK(sc); - cur_tx = sc->vr_cdata.vr_tx_prod; while (cur_tx->vr_mbuf == NULL) { IF_DEQUEUE(&ifp->if_snd, m_head); @@ -1404,19 +1422,26 @@ vr_start(struct ifnet *ifp) if (cur_tx->vr_mbuf != NULL) ifp->if_flags |= IFF_OACTIVE; } - - VR_UNLOCK(sc); } static void vr_init(void *xsc) { struct vr_softc *sc = xsc; + + VR_LOCK(sc); + vr_init_locked(sc); + VR_UNLOCK(sc); +} + +static void +vr_init_locked(struct vr_softc *sc) +{ struct ifnet *ifp = &sc->arpcom.ac_if; struct mii_data *mii; int i; - VR_LOCK(sc); + VR_LOCK_ASSERT(sc); mii = device_get_softc(sc->vr_miibus); @@ -1453,7 +1478,6 @@ vr_init(void *xsc) printf( "vr%d: initialization failed: no memory for rx buffers\n", sc->vr_unit); vr_stop(sc); - VR_UNLOCK(sc); return; } @@ -1509,8 +1533,6 @@ vr_init(void *xsc) ifp->if_flags &= ~IFF_OACTIVE; sc->vr_stat_ch = timeout(vr_tick, sc, hz); - - VR_UNLOCK(sc); } /* @@ -1552,15 +1574,14 @@ vr_ioctl(struct ifnet *ifp, u_long command, caddr_t data) switch (command) { case SIOCSIFFLAGS: + VR_LOCK(sc); if (ifp->if_flags & IFF_UP) { - vr_init(sc); + vr_init_locked(sc); } else { - if (ifp->if_flags & IFF_RUNNING) { - VR_LOCK(sc); + if (ifp->if_flags & IFF_RUNNING) vr_stop(sc); - VR_UNLOCK(sc); - } } + VR_UNLOCK(sc); error = 0; break; case SIOCADDMULTI: @@ -1592,16 +1613,18 @@ vr_watchdog(struct ifnet *ifp) struct vr_softc *sc = ifp->if_softc; VR_LOCK(sc); + ifp->if_oerrors++; printf("vr%d: watchdog timeout\n", sc->vr_unit); vr_stop(sc); vr_reset(sc); - VR_UNLOCK(sc); + vr_init_locked(sc); - vr_init(sc); if (ifp->if_snd.ifq_head != NULL) - vr_start(ifp); + vr_start_locked(ifp); + + VR_UNLOCK(sc); } /* -- cgit v1.1