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Instead of using the legacy if_timer/if_watchdog interface create

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our own watchdog that piggybacks on the em_local_timer() routine.

We suppose that the if_timer/if_watchdog interface should be
obsoleted, since it doesn't fit the modern SMP network stack.
NIC drivers should create their own watchdogs, that check and
clear the timers always holding driver's lock.

In collaboration with:	jfv, scottl
This commit is contained in:
glebius 2006-11-09 16:00:18 +00:00
parent 3fd21f0a5b
commit c49e0d6935
2 changed files with 30 additions and 26 deletions
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55
sys/dev/em/if_em.c
View File

@ -205,7 +205,7 @@ static int em_resume(device_t);
static void em_start(struct ifnet *);
static void em_start_locked(struct ifnet *ifp);
static int em_ioctl(struct ifnet *, u_long, caddr_t);
static void em_watchdog(struct ifnet *);
static void em_watchdog(struct adapter *);
static void em_init(void *);
static void em_init_locked(struct adapter *);
static void em_stop(void *);
@ -764,7 +764,7 @@ em_start_locked(struct ifnet *ifp)
BPF_MTAP(ifp, m_head);
/* Set timeout in case hardware has problems transmitting. */
ifp->if_timer = EM_TX_TIMEOUT;
adapter->watchdog_timer = EM_TX_TIMEOUT;
}
}
@ -971,47 +971,46 @@ em_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
}
/*********************************************************************
* Watchdog entry point
* Watchdog timer:
*
* This routine is called whenever hardware quits transmitting.
* This routine is called from the local timer every second.
* As long as transmit descriptors are being cleaned the value
* is non-zero and we do nothing. Reaching 0 indicates a tx hang
* and we then reset the device.
*
**********************************************************************/
static void
em_watchdog(struct ifnet *ifp)
em_watchdog(struct adapter *adapter)
{
struct adapter *adapter = ifp->if_softc;
EM_LOCK(adapter);
EM_LOCK_ASSERT(adapter);
/*
* The timer is set to 5 every time em_start() queues a packet.
* Then em_txeof() keeps resetting to 5 as long as it cleans at
* least one descriptor.
* Finally, anytime all descriptors are clean the timer is
* set to 0.
*/
if (adapter->watchdog_timer == 0 || --adapter->watchdog_timer)
return;
/* If we are in this routine because of pause frames, then
* don't reset the hardware.
*/
if (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_TXOFF) {
ifp->if_timer = EM_TX_TIMEOUT;
EM_UNLOCK(adapter);
return;
}
/*
* Reclaim first as there is a possibility of losing Tx completion
* interrupts. Possible cause of missing Tx completion interrupts
* comes from Tx interrupt moderation mechanism(delayed interrupts)
* or chipset bug.
*/
em_txeof(adapter);
if (adapter->num_tx_desc_avail == adapter->num_tx_desc) {
EM_UNLOCK(adapter);
adapter->watchdog_timer = EM_TX_TIMEOUT;
return;
}
if (em_check_for_link(&adapter->hw) == 0)
device_printf(adapter->dev, "watchdog timeout -- resetting\n");
ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
adapter->ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
adapter->watchdog_events++;
em_init_locked(adapter);
EM_UNLOCK(adapter);
}
/*********************************************************************
@ -2033,6 +2032,11 @@ em_local_timer(void *arg)
if (em_display_debug_stats && ifp->if_drv_flags & IFF_DRV_RUNNING)
em_print_hw_stats(adapter);
em_smartspeed(adapter);
/*
* Each second we check the watchdog to
* protect against hardware hangs.
*/
em_watchdog(adapter);
callout_reset(&adapter->timer, hz, em_local_timer, adapter);
}
@ -2391,7 +2395,6 @@ em_setup_interface(device_t dev, struct adapter *adapter)
ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
ifp->if_ioctl = em_ioctl;
ifp->if_start = em_start;
ifp->if_watchdog = em_watchdog;
IFQ_SET_MAXLEN(&ifp->if_snd, adapter->num_tx_desc - 1);
ifp->if_snd.ifq_drv_maxlen = adapter->num_tx_desc - 1;
IFQ_SET_READY(&ifp->if_snd);
@ -3212,9 +3215,9 @@ em_txeof(struct adapter *adapter)
if (num_avail > EM_TX_CLEANUP_THRESHOLD) {
ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
if (num_avail == adapter->num_tx_desc)
ifp->if_timer = 0;
adapter->watchdog_timer = 0;
else if (num_avail != adapter->num_tx_desc_avail)
ifp->if_timer = EM_TX_TIMEOUT;
adapter->watchdog_timer = EM_TX_TIMEOUT;
}
adapter->num_tx_desc_avail = num_avail;
}

1
sys/dev/em/if_em.h
View File

@ -286,6 +286,7 @@ struct adapter {
struct ifmedia media;
struct callout timer;
struct callout tx_fifo_timer;
int watchdog_timer;
int io_rid;
int if_flags;
struct mtx mtx;