Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 7c2e9ba3 authored by Julian Wiedmann's avatar Julian Wiedmann Committed by David S. Miller
Browse files

s390/qeth: don't take queue lock in send_packet_fast() 



Locking the output queue prior to TX is needed on OSA devices,
to synchronize against a packing flush from the TX completion code
(via qeth_check_outbound_queue()).
But send_packet_fast() is only used for IQDs, which don't do packing.
So remove the locking, and apply some easy cleanups.

Signed-off-by: default avatarJulian Wiedmann <jwi@linux.vnet.ibm.com>
Reviewed-by: default avatarUrsula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 96279230

drivers/s390/net/qeth_core.h

+1 −2
Original line number Diff line number Diff line
@@ -962,8 +962,7 @@ int qeth_get_priority_queue(struct qeth_card *, struct sk_buff *, int, int); 
int qeth_get_elements_no(struct qeth_card *card, struct sk_buff *skb,

			 int extra_elems, int data_offset);

int qeth_get_elements_for_frags(struct sk_buff *);

int qeth_do_send_packet_fast(struct qeth_card *card,

			     struct qeth_qdio_out_q *queue, struct sk_buff *skb,

int qeth_do_send_packet_fast(struct qeth_qdio_out_q *queue, struct sk_buff *skb,

			     struct qeth_hdr *hdr, unsigned int offset,

			     unsigned int hd_len);

int qeth_do_send_packet(struct qeth_card *card, struct qeth_qdio_out_q *queue,

drivers/s390/net/qeth_core_main.c

+5 −17
Original line number Diff line number Diff line
@@ -4040,35 +4040,23 @@ static int qeth_fill_buffer(struct qeth_qdio_out_q *queue, 
	return flush_cnt;

}



int qeth_do_send_packet_fast(struct qeth_card *card,

			     struct qeth_qdio_out_q *queue, struct sk_buff *skb,

int qeth_do_send_packet_fast(struct qeth_qdio_out_q *queue, struct sk_buff *skb,

			     struct qeth_hdr *hdr, unsigned int offset,

			     unsigned int hd_len)

{

	struct qeth_qdio_out_buffer *buffer;

	int index;

	int index = queue->next_buf_to_fill;

	struct qeth_qdio_out_buffer *buffer = queue->bufs[index];



	/* spin until we get the queue ... */

	while (atomic_cmpxchg(&queue->state, QETH_OUT_Q_UNLOCKED,

			      QETH_OUT_Q_LOCKED) != QETH_OUT_Q_UNLOCKED);

	/* ... now we've got the queue */

	index = queue->next_buf_to_fill;

	buffer = queue->bufs[queue->next_buf_to_fill];

	/*

	 * check if buffer is empty to make sure that we do not 'overtake'

	 * ourselves and try to fill a buffer that is already primed

	 */

	if (atomic_read(&buffer->state) != QETH_QDIO_BUF_EMPTY)

		goto out;

	queue->next_buf_to_fill = (queue->next_buf_to_fill + 1) %

					  QDIO_MAX_BUFFERS_PER_Q;

	atomic_set(&queue->state, QETH_OUT_Q_UNLOCKED);

		return -EBUSY;

	queue->next_buf_to_fill = (index + 1) % QDIO_MAX_BUFFERS_PER_Q;

	qeth_fill_buffer(queue, buffer, skb, hdr, offset, hd_len);

	qeth_flush_buffers(queue, index, 1);

	return 0;

out:

	atomic_set(&queue->state, QETH_OUT_Q_UNLOCKED);

	return -EBUSY;

}

EXPORT_SYMBOL_GPL(qeth_do_send_packet_fast);

drivers/s390/net/qeth_l2_main.c

+1 −1
Original line number Diff line number Diff line
@@ -698,7 +698,7 @@ static int qeth_l2_xmit_iqd(struct qeth_card *card, struct sk_buff *skb, 
		rc = -E2BIG;

		goto out;

	}

	rc = qeth_do_send_packet_fast(card, queue, skb, hdr, data_offset,

	rc = qeth_do_send_packet_fast(queue, skb, hdr, data_offset,

				      sizeof(*hdr) + data_offset);

out:

	if (rc)

drivers/s390/net/qeth_l3_main.c

+2 −2
Original line number Diff line number Diff line
@@ -2771,8 +2771,8 @@ static netdev_tx_t qeth_l3_hard_start_xmit(struct sk_buff *skb, 
		rc = qeth_do_send_packet(card, queue, new_skb, hdr, hd_len,

					 hd_len, elements);

	} else

		rc = qeth_do_send_packet_fast(card, queue, new_skb, hdr,

					      data_offset, hd_len);

		rc = qeth_do_send_packet_fast(queue, new_skb, hdr, data_offset,

					      hd_len);



	if (!rc) {

		card->stats.tx_packets++;