diff --git a/drivers/infiniband/hw/hfi1/ipoib.h b/drivers/infiniband/hw/hfi1/ipoib.h index 185c9b02c974..b8c9d0a003fb 100644 --- a/drivers/infiniband/hw/hfi1/ipoib.h +++ b/drivers/infiniband/hw/hfi1/ipoib.h @@ -67,6 +67,9 @@ struct hfi1_ipoib_circ_buf { * @sde: sdma engine * @tx_list: tx request list * @sent_txreqs: count of txreqs posted to sdma + * @stops: count of stops of queue + * @ring_full: ring has been filled + * @no_desc: descriptor shortage seen * @flow: tracks when list needs to be flushed for a flow change * @q_idx: ipoib Tx queue index * @pkts_sent: indicator packets have been sent from this queue @@ -80,6 +83,9 @@ struct hfi1_ipoib_txq { struct sdma_engine *sde; struct list_head tx_list; u64 sent_txreqs; + atomic_t stops; + atomic_t ring_full; + atomic_t no_desc; union hfi1_ipoib_flow flow; u8 q_idx; bool pkts_sent; diff --git a/drivers/infiniband/hw/hfi1/ipoib_tx.c b/drivers/infiniband/hw/hfi1/ipoib_tx.c index 76dcb5624aa6..9df292b51a05 100644 --- a/drivers/infiniband/hw/hfi1/ipoib_tx.c +++ b/drivers/infiniband/hw/hfi1/ipoib_tx.c @@ -55,23 +55,48 @@ static u64 hfi1_ipoib_txreqs(const u64 sent, const u64 completed) return sent - completed; } +static u64 hfi1_ipoib_used(struct hfi1_ipoib_txq *txq) +{ + return hfi1_ipoib_txreqs(txq->sent_txreqs, + atomic64_read(&txq->complete_txreqs)); +} + +static void hfi1_ipoib_stop_txq(struct hfi1_ipoib_txq *txq) +{ + if (atomic_inc_return(&txq->stops) == 1) + netif_stop_subqueue(txq->priv->netdev, txq->q_idx); +} + +static void hfi1_ipoib_wake_txq(struct hfi1_ipoib_txq *txq) +{ + if (atomic_dec_and_test(&txq->stops)) + netif_wake_subqueue(txq->priv->netdev, txq->q_idx); +} + +static uint hfi1_ipoib_ring_hwat(struct hfi1_ipoib_txq *txq) +{ + return min_t(uint, txq->priv->netdev->tx_queue_len, + txq->tx_ring.max_items - 1); +} + +static uint hfi1_ipoib_ring_lwat(struct hfi1_ipoib_txq *txq) +{ + return min_t(uint, txq->priv->netdev->tx_queue_len, + txq->tx_ring.max_items) >> 1; +} + static void hfi1_ipoib_check_queue_depth(struct hfi1_ipoib_txq *txq) { - if (unlikely(hfi1_ipoib_txreqs(++txq->sent_txreqs, - atomic64_read(&txq->complete_txreqs)) >= - min_t(unsigned int, txq->priv->netdev->tx_queue_len, - txq->tx_ring.max_items - 1))) - netif_stop_subqueue(txq->priv->netdev, txq->q_idx); + ++txq->sent_txreqs; + if (hfi1_ipoib_used(txq) >= hfi1_ipoib_ring_hwat(txq) && + !atomic_xchg(&txq->ring_full, 1)) + hfi1_ipoib_stop_txq(txq); } static void hfi1_ipoib_check_queue_stopped(struct hfi1_ipoib_txq *txq) { struct net_device *dev = txq->priv->netdev; - /* If the queue is already running just return */ - if (likely(!__netif_subqueue_stopped(dev, txq->q_idx))) - return; - /* If shutting down just return as queue state is irrelevant */ if (unlikely(dev->reg_state != NETREG_REGISTERED)) return; @@ -86,11 +111,9 @@ static void hfi1_ipoib_check_queue_stopped(struct hfi1_ipoib_txq *txq) * Use the minimum of the current tx_queue_len or the rings max txreqs * to protect against ring overflow. */ - if (hfi1_ipoib_txreqs(txq->sent_txreqs, - atomic64_read(&txq->complete_txreqs)) - < min_t(unsigned int, dev->tx_queue_len, - txq->tx_ring.max_items) >> 1) - netif_wake_subqueue(dev, txq->q_idx); + if (hfi1_ipoib_used(txq) < hfi1_ipoib_ring_lwat(txq) && + atomic_xchg(&txq->ring_full, 0)) + hfi1_ipoib_wake_txq(txq); } static void hfi1_ipoib_free_tx(struct ipoib_txreq *tx, int budget) @@ -608,13 +631,14 @@ static int hfi1_ipoib_sdma_sleep(struct sdma_engine *sde, return -EAGAIN; } - netif_stop_subqueue(txq->priv->netdev, txq->q_idx); - if (list_empty(&txreq->list)) /* came from non-list submit */ list_add_tail(&txreq->list, &txq->tx_list); - if (list_empty(&txq->wait.list)) + if (list_empty(&txq->wait.list)) { + if (!atomic_xchg(&txq->no_desc, 1)) + hfi1_ipoib_stop_txq(txq); iowait_queue(pkts_sent, wait->iow, &sde->dmawait); + } write_sequnlock(&sde->waitlock); return -EBUSY; @@ -649,9 +673,9 @@ static void hfi1_ipoib_flush_txq(struct work_struct *work) struct net_device *dev = txq->priv->netdev; if (likely(dev->reg_state == NETREG_REGISTERED) && - likely(__netif_subqueue_stopped(dev, txq->q_idx)) && likely(!hfi1_ipoib_flush_tx_list(dev, txq))) - netif_wake_subqueue(dev, txq->q_idx); + if (atomic_xchg(&txq->no_desc, 0)) + hfi1_ipoib_wake_txq(txq); } int hfi1_ipoib_txreq_init(struct hfi1_ipoib_dev_priv *priv) @@ -705,6 +729,9 @@ int hfi1_ipoib_txreq_init(struct hfi1_ipoib_dev_priv *priv) txq->sde = NULL; INIT_LIST_HEAD(&txq->tx_list); atomic64_set(&txq->complete_txreqs, 0); + atomic_set(&txq->stops, 0); + atomic_set(&txq->ring_full, 0); + atomic_set(&txq->no_desc, 0); txq->q_idx = i; txq->flow.tx_queue = 0xff; txq->flow.sc5 = 0xff; @@ -770,7 +797,7 @@ static void hfi1_ipoib_drain_tx_list(struct hfi1_ipoib_txq *txq) atomic64_inc(complete_txreqs); } - if (hfi1_ipoib_txreqs(txq->sent_txreqs, atomic64_read(complete_txreqs))) + if (hfi1_ipoib_used(txq)) dd_dev_warn(txq->priv->dd, "txq %d not empty found %llu requests\n", txq->q_idx,