Commit 3e83d467 authored by Julian Wiedmann's avatar Julian Wiedmann Committed by David S. Miller
Browse files

s390/qeth: schedule TX NAPI on QAOB completion 



When a QAOB notifies us that a pending TX buffer has been delivered, the
actual TX completion processing by qeth_tx_complete_pending_bufs()
is done within the context of a TX NAPI instance. We shouldn't rely on
this instance being scheduled by some other TX event, but just do it
ourselves.

qeth_qdio_handle_aob() is called from qeth_poll(), ie. our main NAPI
instance. To avoid touching the TX queue's NAPI instance
before/after it is (un-)registered, reorder the code in qeth_open()
and qeth_stop() accordingly.

Fixes: 0da9581d ("qeth: exploit asynchronous delivery of storage blocks")
Signed-off-by: default avatarJulian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c20383ad

drivers/s390/net/qeth_core_main.c

+12 −6
Original line number Diff line number Diff line
@@ -470,6 +470,7 @@ static void qeth_qdio_handle_aob(struct qeth_card *card, 
	struct qaob *aob;

	struct qeth_qdio_out_buffer *buffer;

	enum iucv_tx_notify notification;

	struct qeth_qdio_out_q *queue;

	unsigned int i;



	aob = (struct qaob *) phys_to_virt(phys_aob_addr);
@@ -512,7 +513,9 @@ static void qeth_qdio_handle_aob(struct qeth_card *card, 
			buffer->is_header[i] = 0;

		}



		queue = buffer->q;

		atomic_set(&buffer->state, QETH_QDIO_BUF_EMPTY);

		napi_schedule(&queue->napi);

		break;

	default:

		WARN_ON_ONCE(1);
@@ -7235,9 +7238,7 @@ int qeth_open(struct net_device *dev) 
	card->data.state = CH_STATE_UP;

	netif_tx_start_all_queues(dev);



	napi_enable(&card->napi);

	local_bh_disable();

	napi_schedule(&card->napi);

	if (IS_IQD(card)) {

		struct qeth_qdio_out_q *queue;

		unsigned int i;
@@ -7249,8 +7250,12 @@ int qeth_open(struct net_device *dev) 
			napi_schedule(&queue->napi);

		}

	}



	napi_enable(&card->napi);

	napi_schedule(&card->napi);

	/* kick-start the NAPI softirq: */

	local_bh_enable();



	return 0;

}

EXPORT_SYMBOL_GPL(qeth_open);
@@ -7260,6 +7265,11 @@ int qeth_stop(struct net_device *dev) 
	struct qeth_card *card = dev->ml_priv;



	QETH_CARD_TEXT(card, 4, "qethstop");



	napi_disable(&card->napi);

	cancel_delayed_work_sync(&card->buffer_reclaim_work);

	qdio_stop_irq(CARD_DDEV(card));



	if (IS_IQD(card)) {

		struct qeth_qdio_out_q *queue;

		unsigned int i;
@@ -7280,10 +7290,6 @@ int qeth_stop(struct net_device *dev) 
		netif_tx_disable(dev);

	}



	napi_disable(&card->napi);

	cancel_delayed_work_sync(&card->buffer_reclaim_work);

	qdio_stop_irq(CARD_DDEV(card));



	return 0;

}

EXPORT_SYMBOL_GPL(qeth_stop);