Further rl(4) locking improvements:

- Avoid unnecessary re-acquisition elsewhere by adding *_locked()
   entry points as needed.
 - Correct locking for the DEVICE_POLLING case.
 - Hold the driver lock for the entire duration of interrupt servicing,
   to avoid unneeded, expensive re-acquisition; use *_locked() entry
   points as needed.

Reviewed by:	-net (silence)
This commit is contained in:
Bruce M Simpson 2004-07-09 00:07:06 +00:00
parent 0ac4013324
commit cdeef8e7f3
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=131841

View File

@ -187,6 +187,7 @@ static void rl_ifmedia_sts (struct ifnet *, struct ifmediareq *);
static int rl_ioctl (struct ifnet *, u_long, caddr_t);
static void rl_intr (void *);
static void rl_init (void *);
static void rl_init_locked (struct rl_softc *sc);
static void rl_mii_send (struct rl_softc *, uint32_t, int);
static void rl_mii_sync (struct rl_softc *);
static int rl_mii_readreg (struct rl_softc *, struct rl_mii_frame *);
@ -194,6 +195,12 @@ static int rl_mii_writereg (struct rl_softc *, struct rl_mii_frame *);
static int rl_miibus_readreg (device_t, int, int);
static void rl_miibus_statchg (device_t);
static int rl_miibus_writereg (device_t, int, int, int);
#ifdef DEVICE_POLLING
static void rl_poll (struct ifnet *ifp, enum poll_cmd cmd,
int count);
static void rl_poll_locked (struct ifnet *ifp, enum poll_cmd cmd,
int count);
#endif
static int rl_probe (device_t);
static void rl_read_eeprom (struct rl_softc *, uint8_t *, int, int, int);
static void rl_reset (struct rl_softc *);
@ -202,6 +209,7 @@ static void rl_rxeof (struct rl_softc *);
static void rl_setmulti (struct rl_softc *);
static void rl_shutdown (device_t);
static void rl_start (struct ifnet *);
static void rl_start_locked (struct ifnet *);
static void rl_stop (struct rl_softc *);
static int rl_suspend (device_t);
static void rl_tick (void *);
@ -1131,7 +1139,7 @@ rl_rxeof(struct rl_softc *sc)
if (!(rxstat & RL_RXSTAT_RXOK)) {
ifp->if_ierrors++;
rl_init(sc);
rl_init_locked(sc);
return;
}
@ -1234,7 +1242,7 @@ rl_txeof(struct rl_softc *sc)
oldthresh = sc->rl_txthresh;
/* error recovery */
rl_reset(sc);
rl_init(sc);
rl_init_locked(sc);
/*
* If there was a transmit underrun,
* bump the TX threshold.
@ -1269,11 +1277,21 @@ rl_tick(void *xsc)
#ifdef DEVICE_POLLING
static void
rl_poll (struct ifnet *ifp, enum poll_cmd cmd, int count)
rl_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
{
struct rl_softc *sc = ifp->if_softc;
RL_LOCK(sc);
rl_poll_locked(ifp, cmd, count);
RL_UNLOCK(sc);
}
static void
rl_poll_locked(struct ifnet *ifp, enum poll_cmd cmd, int count)
{
struct rl_softc *sc = ifp->if_softc;
RL_LOCK_ASSERT(sc);
if (!(ifp->if_capenable & IFCAP_POLLING)) {
ether_poll_deregister(ifp);
@ -1283,18 +1301,15 @@ rl_poll (struct ifnet *ifp, enum poll_cmd cmd, int count)
if (cmd == POLL_DEREGISTER) {
/* Final call; enable interrupts. */
CSR_WRITE_2(sc, RL_IMR, RL_INTRS);
goto done;
return;
}
sc->rxcycles = count;
rl_rxeof(sc);
rl_txeof(sc);
if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd)) {
RL_UNLOCK(sc);
rl_start(ifp);
RL_LOCK(sc);
}
if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
rl_start_locked(ifp);
if (cmd == POLL_AND_CHECK_STATUS) {
uint16_t status;
@ -1302,7 +1317,7 @@ rl_poll (struct ifnet *ifp, enum poll_cmd cmd, int count)
/* We should also check the status register. */
status = CSR_READ_2(sc, RL_ISR);
if (status == 0xffff)
goto done;
return;
if (status != 0)
CSR_WRITE_2(sc, RL_ISR, status);
@ -1310,13 +1325,9 @@ rl_poll (struct ifnet *ifp, enum poll_cmd cmd, int count)
if (status & RL_ISR_SYSTEM_ERR) {
rl_reset(sc);
RL_UNLOCK(sc);
rl_init(sc);
RL_LOCK(sc);
rl_init_locked(sc);
}
}
done:
RL_UNLOCK(sc);
}
#endif /* DEVICE_POLLING */
@ -1329,23 +1340,19 @@ rl_intr(void *arg)
RL_LOCK(sc);
if (sc->suspended) {
RL_UNLOCK(sc);
return;
}
if (sc->suspended)
goto done_locked;
#ifdef DEVICE_POLLING
if (ifp->if_flags & IFF_POLLING) {
RL_UNLOCK(sc);
return;
}
if (ifp->if_flags & IFF_POLLING)
goto done_locked;
if ((ifp->if_capenable & IFCAP_POLLING) &&
ether_poll_register(rl_poll, ifp)) {
/* Disable interrupts. */
CSR_WRITE_2(sc, RL_IMR, 0x0000);
RL_UNLOCK(sc);
rl_poll(ifp, 0, 1);
return;
rl_poll_locked(ifp, 0, 1);
goto done_locked;
}
#endif /* DEVICE_POLLING */
@ -1366,16 +1373,15 @@ rl_intr(void *arg)
rl_txeof(sc);
if (status & RL_ISR_SYSTEM_ERR) {
rl_reset(sc);
RL_UNLOCK(sc);
rl_init(sc);
RL_LOCK(sc);
rl_init_locked(sc);
}
}
RL_UNLOCK(sc);
if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
rl_start(ifp);
rl_start_locked(ifp);
done_locked:
RL_UNLOCK(sc);
}
/*
@ -1425,23 +1431,33 @@ rl_encap(struct rl_softc *sc, struct mbuf *m_head)
/*
* Main transmit routine.
*/
static void
rl_start(struct ifnet *ifp)
{
struct rl_softc *sc = ifp->if_softc;
struct mbuf *m_head = NULL;
RL_LOCK(sc);
rl_start_locked(ifp);
RL_UNLOCK(sc);
}
static void
rl_start_locked(struct ifnet *ifp)
{
struct rl_softc *sc = ifp->if_softc;
struct mbuf *m_head = NULL;
RL_LOCK_ASSERT(sc);
while (RL_CUR_TXMBUF(sc) == NULL) {
IFQ_DRV_DEQUEUE(&ifp->if_snd, m_head);
if (m_head == NULL)
break;
if (rl_encap(sc, m_head)) {
if (rl_encap(sc, m_head))
break;
}
/* Pass a copy of this mbuf chain to the bpf subsystem. */
BPF_MTAP(ifp, RL_CUR_TXMBUF(sc));
@ -1470,19 +1486,27 @@ rl_start(struct ifnet *ifp)
*/
if (RL_CUR_TXMBUF(sc) != NULL)
ifp->if_flags |= IFF_OACTIVE;
RL_UNLOCK(sc);
}
static void
rl_init(void *xsc)
{
struct rl_softc *sc = xsc;
RL_LOCK(sc);
rl_init_locked(sc);
RL_UNLOCK(sc);
}
static void
rl_init_locked(struct rl_softc *sc)
{
struct ifnet *ifp = &sc->arpcom.ac_if;
struct mii_data *mii;
uint32_t rxcfg = 0;
RL_LOCK(sc);
RL_LOCK_ASSERT(sc);
mii = device_get_softc(sc->rl_miibus);
/*
@ -1573,8 +1597,6 @@ rl_init(void *xsc)
ifp->if_flags &= ~IFF_OACTIVE;
sc->rl_stat_ch = timeout(rl_tick, sc, hz);
RL_UNLOCK(sc);
}
/*
@ -1619,14 +1641,14 @@ rl_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
switch (command) {
case SIOCSIFFLAGS:
RL_LOCK(sc);
if (ifp->if_flags & IFF_UP) {
rl_init(sc);
rl_init_locked(sc);
} else {
if (ifp->if_flags & IFF_RUNNING)
RL_LOCK(sc);
rl_stop(sc);
RL_UNLOCK(sc);
}
RL_UNLOCK(sc);
error = 0;
break;
case SIOCADDMULTI:
@ -1665,10 +1687,9 @@ rl_watchdog(struct ifnet *ifp)
rl_txeof(sc);
rl_rxeof(sc);
rl_init_locked(sc);
RL_UNLOCK(sc);
rl_init(sc);
}
/*
@ -1745,12 +1766,14 @@ rl_resume(device_t dev)
sc = device_get_softc(dev);
ifp = &sc->arpcom.ac_if;
RL_LOCK(sc);
/* reinitialize interface if necessary */
if (ifp->if_flags & IFF_UP)
rl_init(sc);
rl_init_locked(sc);
RL_LOCK(sc);
sc->suspended = 0;
RL_UNLOCK(sc);
return (0);