IB/hfi1: Prepare resource waits for dual leg

Current implementation allows each qp to have only one send engine.  As
such, each qp has only one list to queue prebuilt packets when send engine
resources are not available. To improve performance, it is desired to
support multiple send engines for each qp.

This patch creates the framework to support two send engines
(two legs) for each qp for the TID RDMA protocol, which can be easily
extended to support more send engines. It achieves the goal by creating a
leg specific struct, iowait_work in the iowait struct, to hold the
work_struct and the tx_list as well as a pointer to the parent iowait
struct.

The hfi1_pkt_state now has an additional field to record the current legs
work structure and that is now passed to all egress waiters to determine
the leg that needs to wait via a new iowait helper.  The APIs are adjusted
to use the new leg specific struct as required.

Many new and modified helpers are added to support this change.

Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 20 insertions, 32 deletions

diff --git a/drivers/infiniband/hw/hfi1/sdma.c b/drivers/infiniband/hw/hfi1/sdma.c
index 7a9b67e82a96..891d2386d1ca 100644
--- a/drivers/infiniband/hw/hfi1/sdma.c
+++ b/drivers/infiniband/hw/hfi1/sdma.c
@@ -378,7 +378,7 @@ static inline void complete_tx(struct sdma_engine *sde,
 	__sdma_txclean(sde->dd, tx);
 	if (complete)
 		(*complete)(tx, res);
-	if (wait && iowait_sdma_dec(wait))
+	if (iowait_sdma_dec(wait))
 		iowait_drain_wakeup(wait);
 }
 
@@ -1758,7 +1758,6 @@ static void sdma_desc_avail(struct sdma_engine *sde, uint avail)
 	struct iowait *wait, *nw;
 	struct iowait *waits[SDMA_WAIT_BATCH_SIZE];
 	uint i, n = 0, seq, max_idx = 0;
-	struct sdma_txreq *stx;
 	struct hfi1_ibdev *dev = &sde->dd->verbs_dev;
 	u8 max_starved_cnt = 0;
 
@@ -1779,19 +1778,13 @@ static void sdma_desc_avail(struct sdma_engine *sde, uint avail)
 					nw,
 					&sde->dmawait,
 					list) {
-				u16 num_desc = 0;
+				u32 num_desc;
 
 				if (!wait->wakeup)
 					continue;
 				if (n == ARRAY_SIZE(waits))
 					break;
-				if (!list_empty(&wait->tx_head)) {
-					stx = list_first_entry(
-						&wait->tx_head,
-						struct sdma_txreq,
-						list);
-					num_desc = stx->num_desc;
-				}
+				num_desc = iowait_get_all_desc(wait);
 				if (num_desc > avail)
 					break;
 				avail -= num_desc;
@@ -2346,7 +2339,7 @@ static inline u16 submit_tx(struct sdma_engine *sde, struct sdma_txreq *tx)
  */
 static int sdma_check_progress(
 	struct sdma_engine *sde,
-	struct iowait *wait,
+	struct iowait_work *wait,
 	struct sdma_txreq *tx,
 	bool pkts_sent)
 {
@@ -2356,12 +2349,12 @@ static int sdma_check_progress(
 	if (tx->num_desc <= sde->desc_avail)
 		return -EAGAIN;
 	/* pulse the head_lock */
-	if (wait && wait->sleep) {
+	if (wait && iowait_ioww_to_iow(wait)->sleep) {
 		unsigned seq;
 
 		seq = raw_seqcount_begin(
 			(const seqcount_t *)&sde->head_lock.seqcount);
-		ret = wait->sleep(sde, wait, tx, seq, pkts_sent);
+		ret = wait->iow->sleep(sde, wait, tx, seq, pkts_sent);
 		if (ret == -EAGAIN)
 			sde->desc_avail = sdma_descq_freecnt(sde);
 	} else {
@@ -2373,7 +2366,7 @@ static int sdma_check_progress(
 /**
  * sdma_send_txreq() - submit a tx req to ring
  * @sde: sdma engine to use
- * @wait: wait structure to use when full (may be NULL)
+ * @wait: SE wait structure to use when full (may be NULL)
  * @tx: sdma_txreq to submit
  * @pkts_sent: has any packet been sent yet?
  *
@@ -2386,7 +2379,7 @@ static int sdma_check_progress(
  * -EIOCBQUEUED - tx queued to iowait, -ECOMM bad sdma state
  */
 int sdma_send_txreq(struct sdma_engine *sde,
-		    struct iowait *wait,
+		    struct iowait_work *wait,
 		    struct sdma_txreq *tx,
 		    bool pkts_sent)
 {
@@ -2397,7 +2390,7 @@ int sdma_send_txreq(struct sdma_engine *sde,
 	/* user should have supplied entire packet */
 	if (unlikely(tx->tlen))
 		return -EINVAL;
-	tx->wait = wait;
+	tx->wait = iowait_ioww_to_iow(wait);
 	spin_lock_irqsave(&sde->tail_lock, flags);
 retry:
 	if (unlikely(!__sdma_running(sde)))
@@ -2406,14 +2399,14 @@ retry:
 		goto nodesc;
 	tail = submit_tx(sde, tx);
 	if (wait)
-		iowait_sdma_inc(wait);
+		iowait_sdma_inc(iowait_ioww_to_iow(wait));
 	sdma_update_tail(sde, tail);
 unlock:
 	spin_unlock_irqrestore(&sde->tail_lock, flags);
 	return ret;
 unlock_noconn:
 	if (wait)
-		iowait_sdma_inc(wait);
+		iowait_sdma_inc(iowait_ioww_to_iow(wait));
 	tx->next_descq_idx = 0;
 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
 	tx->sn = sde->tail_sn++;
@@ -2422,10 +2415,7 @@ unlock_noconn:
 	spin_lock(&sde->flushlist_lock);
 	list_add_tail(&tx->list, &sde->flushlist);
 	spin_unlock(&sde->flushlist_lock);
-	if (wait) {
-		wait->tx_count++;
-		wait->count += tx->num_desc;
-	}
+	iowait_inc_wait_count(wait, tx->num_desc);
 	schedule_work(&sde->flush_worker);
 	ret = -ECOMM;
 	goto unlock;
@@ -2442,7 +2432,7 @@ nodesc:
 /**
  * sdma_send_txlist() - submit a list of tx req to ring
  * @sde: sdma engine to use
- * @wait: wait structure to use when full (may be NULL)
+ * @wait: SE wait structure to use when full (may be NULL)
  * @tx_list: list of sdma_txreqs to submit
  * @count: pointer to a u16 which, after return will contain the total number of
  *         sdma_txreqs removed from the tx_list. This will include sdma_txreqs
@@ -2467,7 +2457,7 @@ nodesc:
  * -EINVAL - sdma_txreq incomplete, -EBUSY - no space in ring (wait == NULL)
  * -EIOCBQUEUED - tx queued to iowait, -ECOMM bad sdma state
  */
-int sdma_send_txlist(struct sdma_engine *sde, struct iowait *wait,
+int sdma_send_txlist(struct sdma_engine *sde, struct iowait_work *wait,
 		     struct list_head *tx_list, u16 *count_out)
 {
 	struct sdma_txreq *tx, *tx_next;
@@ -2479,7 +2469,7 @@ int sdma_send_txlist(struct sdma_engine *sde, struct iowait *wait,
 	spin_lock_irqsave(&sde->tail_lock, flags);
 retry:
 	list_for_each_entry_safe(tx, tx_next, tx_list, list) {
-		tx->wait = wait;
+		tx->wait = iowait_ioww_to_iow(wait);
 		if (unlikely(!__sdma_running(sde)))
 			goto unlock_noconn;
 		if (unlikely(tx->num_desc > sde->desc_avail))
@@ -2500,8 +2490,9 @@ retry:
 update_tail:
 	total_count = submit_count + flush_count;
 	if (wait) {
-		iowait_sdma_add(wait, total_count);
-		iowait_starve_clear(submit_count > 0, wait);
+		iowait_sdma_add(iowait_ioww_to_iow(wait), total_count);
+		iowait_starve_clear(submit_count > 0,
+				    iowait_ioww_to_iow(wait));
 	}
 	if (tail != INVALID_TAIL)
 		sdma_update_tail(sde, tail);
@@ -2511,7 +2502,7 @@ update_tail:
 unlock_noconn:
 	spin_lock(&sde->flushlist_lock);
 	list_for_each_entry_safe(tx, tx_next, tx_list, list) {
-		tx->wait = wait;
+		tx->wait = iowait_ioww_to_iow(wait);
 		list_del_init(&tx->list);
 		tx->next_descq_idx = 0;
 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
@@ -2520,10 +2511,7 @@ unlock_noconn:
 #endif
 		list_add_tail(&tx->list, &sde->flushlist);
 		flush_count++;
-		if (wait) {
-			wait->tx_count++;
-			wait->count += tx->num_desc;
-		}
+		iowait_inc_wait_count(wait, tx->num_desc);
 	}
 	spin_unlock(&sde->flushlist_lock);
 	schedule_work(&sde->flush_worker);