qdio_flags = QDIO_FLAG_SYNC_OUTPUT;
if (atomic_read(&queue->set_pci_flags_count))
qdio_flags |= QDIO_FLAG_PCI_OUT;
- atomic_add(count, &queue->used_buffers);
rc = do_QDIO(CARD_DDEV(queue->card), qdio_flags,
queue->queue_no, index, count);
if (rc) {
* do_send_packet. So, we check if there is a
* packing buffer to be flushed here.
*/
- netif_stop_subqueue(queue->card->dev, queue->queue_no);
index = queue->next_buf_to_fill;
q_was_packing = queue->do_pack;
/* queue->do_pack may change */
struct qeth_qdio_out_q *queue = card->qdio.out_qs[__queue];
struct qeth_qdio_out_buffer *buffer;
struct net_device *dev = card->dev;
- u16 txq;
+ struct netdev_queue *txq;
int i;
QETH_CARD_TEXT(card, 6, "qdouhdl");
if (card->info.type != QETH_CARD_TYPE_IQD)
qeth_check_outbound_queue(queue);
- txq = IS_IQD(card) ? qeth_iqd_translate_txq(dev, __queue) : __queue;
- netif_wake_subqueue(dev, txq);
+ if (IS_IQD(card))
+ __queue = qeth_iqd_translate_txq(dev, __queue);
+ txq = netdev_get_tx_queue(dev, __queue);
+ /* xmit may have observed the full-condition, but not yet stopped the
+ * txq. In which case the code below won't trigger. So before returning,
+ * xmit will re-check the txq's fill level and wake it up if needed.
+ */
+ if (netif_tx_queue_stopped(txq) && !qeth_out_queue_is_full(queue))
+ netif_tx_wake_queue(txq);
}
/**
* from qeth_core_header_cache.
* @offset: when mapping the skb, start at skb->data + offset
* @hd_len: if > 0, build a dedicated header element of this size
+ * flush: Prepare the buffer to be flushed, regardless of its fill level.
*/
static int qeth_fill_buffer(struct qeth_qdio_out_q *queue,
struct qeth_qdio_out_buffer *buf,
struct sk_buff *skb, struct qeth_hdr *hdr,
- unsigned int offset, unsigned int hd_len)
+ unsigned int offset, unsigned int hd_len,
+ bool flush)
{
struct qdio_buffer *buffer = buf->buffer;
bool is_first_elem = true;
QETH_TXQ_STAT_INC(queue, skbs_pack);
/* If the buffer still has free elements, keep using it. */
- if (buf->next_element_to_fill <
- QETH_MAX_BUFFER_ELEMENTS(queue->card))
+ if (!flush && buf->next_element_to_fill <
+ QETH_MAX_BUFFER_ELEMENTS(queue->card))
return 0;
}
{
int index = queue->next_buf_to_fill;
struct qeth_qdio_out_buffer *buffer = queue->bufs[index];
+ struct netdev_queue *txq;
+ bool stopped = false;
- /*
- * check if buffer is empty to make sure that we do not 'overtake'
- * ourselves and try to fill a buffer that is already primed
+ /* Just a sanity check, the wake/stop logic should ensure that we always
+ * get a free buffer.
*/
if (atomic_read(&buffer->state) != QETH_QDIO_BUF_EMPTY)
return -EBUSY;
- qeth_fill_buffer(queue, buffer, skb, hdr, offset, hd_len);
+
+ txq = netdev_get_tx_queue(queue->card->dev, skb_get_queue_mapping(skb));
+
+ if (atomic_inc_return(&queue->used_buffers) >= QDIO_MAX_BUFFERS_PER_Q) {
+ /* If a TX completion happens right _here_ and misses to wake
+ * the txq, then our re-check below will catch the race.
+ */
+ QETH_TXQ_STAT_INC(queue, stopped);
+ netif_tx_stop_queue(txq);
+ stopped = true;
+ }
+
+ qeth_fill_buffer(queue, buffer, skb, hdr, offset, hd_len, stopped);
qeth_flush_buffers(queue, index, 1);
+
+ if (stopped && !qeth_out_queue_is_full(queue))
+ netif_tx_start_queue(txq);
return 0;
}
int elements_needed)
{
struct qeth_qdio_out_buffer *buffer;
+ struct netdev_queue *txq;
+ bool stopped = false;
int start_index;
int flush_count = 0;
int do_pack = 0;
QETH_OUT_Q_LOCKED) != QETH_OUT_Q_UNLOCKED);
start_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
+
+ /* Just a sanity check, the wake/stop logic should ensure that we always
+ * get a free buffer.
*/
if (atomic_read(&buffer->state) != QETH_QDIO_BUF_EMPTY) {
atomic_set(&queue->state, QETH_OUT_Q_UNLOCKED);
return -EBUSY;
}
+
+ txq = netdev_get_tx_queue(card->dev, skb_get_queue_mapping(skb));
+
/* check if we need to switch packing state of this queue */
qeth_switch_to_packing_if_needed(queue);
if (queue->do_pack) {
(queue->next_buf_to_fill + 1) %
QDIO_MAX_BUFFERS_PER_Q;
buffer = queue->bufs[queue->next_buf_to_fill];
- /* we did a step forward, so check buffer state
- * again */
+
+ /* We stepped forward, so sanity-check again: */
if (atomic_read(&buffer->state) !=
QETH_QDIO_BUF_EMPTY) {
qeth_flush_buffers(queue, start_index,
}
}
- flush_count += qeth_fill_buffer(queue, buffer, skb, hdr, offset,
- hd_len);
+ if (buffer->next_element_to_fill == 0 &&
+ atomic_inc_return(&queue->used_buffers) >= QDIO_MAX_BUFFERS_PER_Q) {
+ /* If a TX completion happens right _here_ and misses to wake
+ * the txq, then our re-check below will catch the race.
+ */
+ QETH_TXQ_STAT_INC(queue, stopped);
+ netif_tx_stop_queue(txq);
+ stopped = true;
+ }
+
+ flush_count += qeth_fill_buffer(queue, buffer, skb, hdr, offset, hd_len,
+ stopped);
if (flush_count)
qeth_flush_buffers(queue, start_index, flush_count);
else if (!atomic_read(&queue->set_pci_flags_count))
if (do_pack)
QETH_TXQ_STAT_ADD(queue, bufs_pack, flush_count);
+ if (stopped && !qeth_out_queue_is_full(queue))
+ netif_tx_start_queue(txq);
return rc;
}
EXPORT_SYMBOL_GPL(qeth_do_send_packet);
} else {
if (!push_len)
kmem_cache_free(qeth_core_header_cache, hdr);
- if (rc == -EBUSY)
- /* roll back to ETH header */
- skb_pull(skb, push_len);
}
return rc;
}
static int qeth_l3_xmit(struct qeth_card *card, struct sk_buff *skb,
struct qeth_qdio_out_q *queue, int ipv, int cast_type)
{
- unsigned char eth_hdr[ETH_HLEN];
unsigned int hw_hdr_len;
int rc;
rc = skb_cow_head(skb, hw_hdr_len - ETH_HLEN);
if (rc)
return rc;
- skb_copy_from_linear_data(skb, eth_hdr, ETH_HLEN);
skb_pull(skb, ETH_HLEN);
qeth_l3_fixup_headers(skb);
- rc = qeth_xmit(card, skb, queue, ipv, cast_type, qeth_l3_fill_header);
- if (rc == -EBUSY) {
- /* roll back to ETH header */
- skb_push(skb, ETH_HLEN);
- skb_copy_to_linear_data(skb, eth_hdr, ETH_HLEN);
- }
- return rc;
+ return qeth_xmit(card, skb, queue, ipv, cast_type, qeth_l3_fill_header);
}
static netdev_tx_t qeth_l3_hard_start_xmit(struct sk_buff *skb,
if (cast_type == RTN_BROADCAST && !card->info.broadcast_capable)
goto tx_drop;
- netif_stop_subqueue(dev, txq);
-
if (ipv == 4 || IS_IQD(card))
rc = qeth_l3_xmit(card, skb, queue, ipv, cast_type);
else
if (!rc) {
QETH_TXQ_STAT_INC(queue, tx_packets);
QETH_TXQ_STAT_ADD(queue, tx_bytes, tx_bytes);
- netif_wake_subqueue(dev, txq);
return NETDEV_TX_OK;
- } else if (rc == -EBUSY) {
- return NETDEV_TX_BUSY;
- } /* else fall through */
+ }
tx_drop:
QETH_TXQ_STAT_INC(queue, tx_dropped);
kfree_skb(skb);
- netif_wake_subqueue(dev, txq);
return NETDEV_TX_OK;
}
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