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, 12 insertions, 9 deletions

diff --git a/drivers/infiniband/hw/hfi1/vnic_sdma.c b/drivers/infiniband/hw/hfi1/vnic_sdma.c
index c3c96c5869ed..97bd940a056a 100644
--- a/drivers/infiniband/hw/hfi1/vnic_sdma.c
+++ b/drivers/infiniband/hw/hfi1/vnic_sdma.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(c) 2017 Intel Corporation.
+ * Copyright(c) 2017 - 2018 Intel Corporation.
  *
  * This file is provided under a dual BSD/GPLv2 license.  When using or
  * redistributing this file, you may do so under either license.
@@ -198,8 +198,8 @@ int hfi1_vnic_send_dma(struct hfi1_devdata *dd, u8 q_idx,
 		goto free_desc;
 	tx->retry_count = 0;
 
-	ret = sdma_send_txreq(sde, &vnic_sdma->wait, &tx->txreq,
-			      vnic_sdma->pkts_sent);
+	ret = sdma_send_txreq(sde, iowait_get_ib_work(&vnic_sdma->wait),
+			      &tx->txreq, vnic_sdma->pkts_sent);
 	/* When -ECOMM, sdma callback will be called with ABORT status */
 	if (unlikely(ret && unlikely(ret != -ECOMM)))
 		goto free_desc;
@@ -230,13 +230,13 @@ tx_err:
  * become available.
  */
 static int hfi1_vnic_sdma_sleep(struct sdma_engine *sde,
-				struct iowait *wait,
+				struct iowait_work *wait,
 				struct sdma_txreq *txreq,
 				uint seq,
 				bool pkts_sent)
 {
 	struct hfi1_vnic_sdma *vnic_sdma =
-		container_of(wait, struct hfi1_vnic_sdma, wait);
+		container_of(wait->iow, struct hfi1_vnic_sdma, wait);
 	struct hfi1_ibdev *dev = &vnic_sdma->dd->verbs_dev;
 	struct vnic_txreq *tx = container_of(txreq, struct vnic_txreq, txreq);
 
@@ -247,7 +247,7 @@ static int hfi1_vnic_sdma_sleep(struct sdma_engine *sde,
 	vnic_sdma->state = HFI1_VNIC_SDMA_Q_DEFERRED;
 	write_seqlock(&dev->iowait_lock);
 	if (list_empty(&vnic_sdma->wait.list))
-		iowait_queue(pkts_sent, wait, &sde->dmawait);
+		iowait_queue(pkts_sent, wait->iow, &sde->dmawait);
 	write_sequnlock(&dev->iowait_lock);
 	return -EBUSY;
 }
@@ -285,7 +285,8 @@ void hfi1_vnic_sdma_init(struct hfi1_vnic_vport_info *vinfo)
 	for (i = 0; i < vinfo->num_tx_q; i++) {
 		struct hfi1_vnic_sdma *vnic_sdma = &vinfo->sdma[i];
 
-		iowait_init(&vnic_sdma->wait, 0, NULL, hfi1_vnic_sdma_sleep,
+		iowait_init(&vnic_sdma->wait, 0, NULL, NULL,
+			    hfi1_vnic_sdma_sleep,
 			    hfi1_vnic_sdma_wakeup, NULL);
 		vnic_sdma->sde = &vinfo->dd->per_sdma[i];
 		vnic_sdma->dd = vinfo->dd;
@@ -295,10 +296,12 @@ void hfi1_vnic_sdma_init(struct hfi1_vnic_vport_info *vinfo)
 
 		/* Add a free descriptor watermark for wakeups */
 		if (vnic_sdma->sde->descq_cnt > HFI1_VNIC_SDMA_DESC_WTRMRK) {
+			struct iowait_work *work;
+
 			INIT_LIST_HEAD(&vnic_sdma->stx.list);
 			vnic_sdma->stx.num_desc = HFI1_VNIC_SDMA_DESC_WTRMRK;
-			list_add_tail(&vnic_sdma->stx.list,
-				      &vnic_sdma->wait.tx_head);
+			work = iowait_get_ib_work(&vnic_sdma->wait);
+			list_add_tail(&vnic_sdma->stx.list, &work->tx_head);
 		}
 	}
 }