Size send WQEs based on max_inline_data

Use the consumer's cap.max_inline_data value to size send queue work
requests, and return the actual value available via the same
structure.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <roland@topspin.com>

3 files changed, 48 insertions, 5 deletions

diff --git a/src/mthca.h b/src/mthca.h
index e292a30..d98e58d 100644
--- a/src/mthca.h
+++ b/src/mthca.h
@@ -284,7 +284,10 @@ extern int mthca_arbel_post_send(struct ibv_qp *ibqp, struct ibv_send_wr *wr,
 				 struct ibv_send_wr **bad_wr);
 extern int mthca_arbel_post_recv(struct ibv_qp *ibqp, struct ibv_recv_wr *wr,
 				 struct ibv_recv_wr **bad_wr);
-extern int mthca_alloc_qp_buf(struct ibv_pd *pd, struct mthca_qp *qp);
+extern int mthca_alloc_qp_buf(struct ibv_pd *pd, struct ibv_qp_cap *cap,
+			      struct mthca_qp *qp);
+extern void mthca_return_cap(struct ibv_pd *pd, struct mthca_qp *qp,
+			     struct ibv_qp_cap *cap);
 extern struct mthca_qp *mthca_find_qp(struct mthca_context *ctx, uint32_t qpn);
 extern int mthca_store_qp(struct mthca_context *ctx, uint32_t qpn, struct mthca_qp *qp);
 extern void mthca_clear_qp(struct mthca_context *ctx, uint32_t qpn);
diff --git a/src/qp.c b/src/qp.c
index f53e8b0..af18934 100644
--- a/src/qp.c
+++ b/src/qp.c
@@ -718,10 +718,17 @@ out:
 	return ret;
 }
 
-int mthca_alloc_qp_buf(struct ibv_pd *pd, struct mthca_qp *qp)
+int mthca_alloc_qp_buf(struct ibv_pd *pd, struct ibv_qp_cap *cap,
+		       struct mthca_qp *qp)
 {
 	int size;
 
+	qp->rq.max_gs 	 = cap->max_recv_sge;
+	qp->sq.max_gs 	 = align(cap->max_inline_data + sizeof (struct mthca_inline_seg),
+				 sizeof (struct mthca_data_seg)) / sizeof (struct mthca_data_seg);
+	if (qp->sq.max_gs < cap->max_send_sge)
+		qp->sq.max_gs = cap->max_send_sge;
+
 	qp->wrid = malloc((qp->rq.max + qp->sq.max) * sizeof (uint64_t));
 	if (!qp->wrid)
 		return -1;
@@ -796,6 +803,39 @@ int mthca_alloc_qp_buf(struct ibv_pd *pd, struct mthca_qp *qp)
 	return 0;
 }
 
+void mthca_return_cap(struct ibv_pd *pd, struct mthca_qp *qp, struct ibv_qp_cap *cap)
+{
+	/*
+	 * Maximum inline data size is the full WQE size less the size
+	 * of the next segment, inline segment and other non-data segments.
+	 */
+	cap->max_inline_data = (1 << qp->sq.wqe_shift) -
+		sizeof (struct mthca_next_seg) -
+		sizeof (struct mthca_inline_seg);
+
+	switch (qp->qpt) {
+	case IBV_QPT_UD:
+		if (mthca_is_memfree(pd->context))
+			cap->max_inline_data -= sizeof (struct mthca_arbel_ud_seg);
+		else
+			cap->max_inline_data -= sizeof (struct mthca_tavor_ud_seg);
+		break;
+
+	default:
+		/*
+		 * inline data won't be used in the same WQE as an
+		 * atomic or bind segment, so we don't have to
+		 * subtract anything off here.
+		 */
+		break;
+	}
+
+	cap->max_send_wr     = qp->sq.max;
+	cap->max_recv_wr     = qp->rq.max;
+	cap->max_send_sge    = qp->sq.max_gs;
+	cap->max_recv_sge    = qp->rq.max_gs;
+} 
+
 struct mthca_qp *mthca_find_qp(struct mthca_context *ctx, uint32_t qpn)
 {
 	int tind = (qpn & (ctx->num_qps - 1)) >> ctx->qp_table_shift;
diff --git a/src/verbs.c b/src/verbs.c
index 65ecb67..420db5c 100644
--- a/src/verbs.c
+++ b/src/verbs.c
@@ -270,7 +270,6 @@ struct ibv_qp *mthca_create_qp(struct ibv_pd *pd, struct ibv_qp_init_attr *attr)
 	qp->qpt = attr->qp_type;
 
 	qp->sq.max    	 = align_qp_size(pd->context, attr->cap.max_send_wr);
-	qp->sq.max_gs 	 = attr->cap.max_send_sge;
 	qp->sq.next_ind  = 0;
 	qp->sq.last_comp = qp->sq.max - 1;
 	qp->sq.head    	 = 0;
@@ -278,14 +277,13 @@ struct ibv_qp *mthca_create_qp(struct ibv_pd *pd, struct ibv_qp_init_attr *attr)
 	qp->sq.last      = NULL;
 
 	qp->rq.max    	 = align_qp_size(pd->context, attr->cap.max_recv_wr);
-	qp->rq.max_gs 	 = attr->cap.max_recv_sge;
 	qp->rq.next_ind	 = 0;
 	qp->rq.last_comp = qp->rq.max - 1;
 	qp->rq.head    	 = 0;
 	qp->rq.tail    	 = 0;
 	qp->rq.last      = NULL;
 
-	if (mthca_alloc_qp_buf(pd, qp))
+	if (mthca_alloc_qp_buf(pd, &attr->cap, qp))
 		goto err;
 
 	if (pthread_spin_init(&qp->sq.lock, PTHREAD_PROCESS_PRIVATE) ||
@@ -332,6 +330,8 @@ struct ibv_qp *mthca_create_qp(struct ibv_pd *pd, struct ibv_qp_init_attr *attr)
 	if (ret)
 		goto err_destroy;
 
+	mthca_return_cap(pd, qp, &attr->cap);
+
 	return &qp->ibv_qp;
 
 err_destroy: