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be2net: fix INTx ISR for interrupt behaviour on BE2

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On BE2 chip, an interrupt may be raised even when EQ is in un-armed state.
As a result be_intx()::events_get() and be_poll:events_get() can race and
notify an EQ wrongly.

Fix this by counting events only in be_poll(). Commit 0b545a629 fixes
the same issue in the MSI-x path.

But, on Lancer, INTx can be de-asserted only by notifying num evts. This
is not an issue as the above BE2 behavior doesn't exist/has never been
seen on Lancer.

Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sathya Perla 2012-11-27 19:50:02 +00:00 • committed by David S. Miller
commit e49cc34f7a
1 changed files with 23 additions and 31 deletions
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54
drivers/net/ethernet/emulex/benet/be_main.c
View file

@ -1675,24 +1675,6 @@ static inline int events_get(struct be_eq_obj *eqo)
return num;
}
static int event_handle(struct be_eq_obj *eqo)
{
bool rearm = false;
int num = events_get(eqo);
/* Deal with any spurious interrupts that come without events */
if (!num)
rearm = true;
if (num || msix_enabled(eqo->adapter))
be_eq_notify(eqo->adapter, eqo->q.id, rearm, true, num);
if (num)
napi_schedule(&eqo->napi);
return num;
}
/* Leaves the EQ is disarmed state */
static void be_eq_clean(struct be_eq_obj *eqo)
{
@ -2014,15 +1996,23 @@ static int be_rx_cqs_create(struct be_adapter *adapter)
static irqreturn_t be_intx(int irq, void *dev)
{
struct be_adapter *adapter = dev;
int num_evts;
struct be_eq_obj *eqo = dev;
struct be_adapter *adapter = eqo->adapter;
int num_evts = 0;
/* With INTx only one EQ is used */
num_evts = event_handle(&adapter->eq_obj[0]);
if (num_evts)
return IRQ_HANDLED;
else
return IRQ_NONE;
/* On Lancer, clear-intr bit of the EQ DB does not work.
* INTx is de-asserted only on notifying num evts.
*/
if (lancer_chip(adapter))
num_evts = events_get(eqo);
/* The EQ-notify may not de-assert INTx rightaway, causing
* the ISR to be invoked again. So, return HANDLED even when
* num_evts is zero.
*/
be_eq_notify(adapter, eqo->q.id, false, true, num_evts);
napi_schedule(&eqo->napi);
return IRQ_HANDLED;
}
static irqreturn_t be_msix(int irq, void *dev)
@ -2342,10 +2332,10 @@ static int be_irq_register(struct be_adapter *adapter)
return status;
}
/* INTx */
/* INTx: only the first EQ is used */
netdev->irq = adapter->pdev->irq;
status = request_irq(netdev->irq, be_intx, IRQF_SHARED, netdev->name,
adapter);
&adapter->eq_obj[0]);
if (status) {
dev_err(&adapter->pdev->dev,
"INTx request IRQ failed - err %d\n", status);
@ -2367,7 +2357,7 @@ static void be_irq_unregister(struct be_adapter *adapter)
/* INTx */
if (!msix_enabled(adapter)) {
free_irq(netdev->irq, adapter);
free_irq(netdev->irq, &adapter->eq_obj[0]);
goto done;
}
@ -3023,8 +3013,10 @@ static void be_netpoll(struct net_device *netdev)
struct be_eq_obj *eqo;
int i;
for_all_evt_queues(adapter, eqo, i)
event_handle(eqo);
for_all_evt_queues(adapter, eqo, i) {
be_eq_notify(eqo->adapter, eqo->q.id, false, true, 0);
napi_schedule(&eqo->napi);
}
return;
}