prov/efa: Sender switch to long CTS protocol if runt read fails with …

…ENOMR

Runting read protocol could fail with ENOMR if the EFA provider is unable
to register the buffer with the NIC. In that case, we should fall back
to long CTS instead

This commit is for the changes when the sender fails to register the
source buffer. The sender will switch to the long CTS protocol.

Signed-off-by: Sai Sunku <[email protected]>

prov/efa/src/rdm/efa_rdm_ope.c

@@ -1775,15 +1775,21 @@ ssize_t efa_rdm_ope_post_send_fallback(struct efa_rdm_ope *ope,
 					   int pkt_type, ssize_t err)
 {
 	if (err == -FI_ENOMR) {
+		/* Long read and runting read protocols could fail because of a
+		 * lack of memory registrations. In that case, we retry with
+		 * long CTS protocol
+		 */
 		switch (pkt_type) {
 		case EFA_RDM_LONGREAD_MSGRTM_PKT:
+		case EFA_RDM_RUNTREAD_MSGRTM_PKT:
 			EFA_WARN(FI_LOG_EP_CTRL,
 				 "Sender fallback to long CTS untagged "
 				 "protocol because memory registration limit "
 				 "was reached on the sender\n");
 			return efa_rdm_ope_post_send_or_queue(
 				ope, EFA_RDM_LONGCTS_MSGRTM_PKT);
 		case EFA_RDM_LONGREAD_TAGRTM_PKT:
+		case EFA_RDM_RUNTREAD_TAGRTM_PKT:
 			EFA_WARN(FI_LOG_EP_CTRL,
 				 "Sender fallback to long CTS tagged protocol "
 				 "because memory registration limit was "

prov/efa/src/rdm/efa_rdm_pke_cmd.c

@@ -131,11 +131,17 @@ int efa_rdm_pke_fill_data(struct efa_rdm_pke *pkt_entry,
 		ret = efa_rdm_pke_init_medium_tagrtm(pkt_entry, ope, data_offset, data_size);
 		break;
 	case EFA_RDM_LONGCTS_MSGRTM_PKT:
-		assert(data_offset == 0 && data_size == -1);
+		/* The data_offset will be non-zero when the long CTS RTM packet
+		 * is sent to continue a runting read transfer after the
+		 * receiver has run out of memory registrations */
+		assert((data_offset == 0 || ope->internal_flags & EFA_RDM_OPE_READ_NACK) && data_size == -1);
 		ret = efa_rdm_pke_init_longcts_msgrtm(pkt_entry, ope);
 		break;
 	case EFA_RDM_LONGCTS_TAGRTM_PKT:
-		assert(data_offset == 0 && data_size == -1);
+		/* The data_offset will be non-zero when the long CTS RTM packet
+		 * is sent to continue a runting read transfer after the
+		 * receiver has run out of memory registrations */
+		assert((data_offset == 0 || ope->internal_flags & EFA_RDM_OPE_READ_NACK) && data_size == -1);
 		ret = efa_rdm_pke_init_longcts_tagrtm(pkt_entry, ope);
 		break;
 	case EFA_RDM_LONGREAD_MSGRTM_PKT: