enic: handle spurious error interrupt

Some of the enic adaptors are know to generate spurious interrupts. When
error interrupt is generated, driver just resets the device. This patch
resets the device only when an error is occurred.
Signed-off-by: NGovindarajulu Varadarajan <_govind@gmx.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/cisco/enic/enic_main.c

@@ -178,13 +178,15 @@ static int enic_wq_service(struct vnic_dev *vdev, struct cq_desc *cq_desc,
 	return 0;
 }
 
-static void enic_log_q_error(struct enic *enic)
+static bool enic_log_q_error(struct enic *enic)
 {
 	unsigned int i;
 	u32 error_status;
+	bool err = false;
 
 	for (i = 0; i < enic->wq_count; i++) {
 		error_status = vnic_wq_error_status(&enic->wq[i]);
+		err |= error_status;
 		if (error_status)
 			netdev_err(enic->netdev, "WQ[%d] error_status %d\n",
 				i, error_status);
@@ -192,10 +194,13 @@ static void enic_log_q_error(struct enic *enic)
 
 	for (i = 0; i < enic->rq_count; i++) {
 		error_status = vnic_rq_error_status(&enic->rq[i]);
+		err |= error_status;
 		if (error_status)
 			netdev_err(enic->netdev, "RQ[%d] error_status %d\n",
 				i, error_status);
 	}
+
+	return err;
 }
 
 static void enic_msglvl_check(struct enic *enic)
@@ -333,10 +338,9 @@ static irqreturn_t enic_isr_msix_err(int irq, void *data)
 
 	vnic_intr_return_all_credits(&enic->intr[intr]);
 
-	enic_log_q_error(enic);
-
-	/* schedule recovery from WQ/RQ error */
-	schedule_work(&enic->reset);
+	if (enic_log_q_error(enic))
+		/* schedule recovery from WQ/RQ error */
+		schedule_work(&enic->reset);
 
 	return IRQ_HANDLED;
 }