MCA/COMMON/UCX: enabled fallback into older UCX API

Signed-off-by: Sergey Oblomov <sergeyo@mellanox.com>

Author: Sergey Oblomov

config/ompi_check_ucx.m4

@@ -45,7 +45,7 @@ AC_DEFUN([OMPI_CHECK_UCX],[
                         [OPAL_CHECK_PACKAGE([ompi_check_ucx],
                                    [ucp/api/ucp.h],
                                    [ucp],
-                                   [ucp_ep_flush_nb],
+                                   [ucp_cleanup],
                                    [],
                                    [],
                                    [],
@@ -77,7 +77,7 @@ AC_DEFUN([OMPI_CHECK_UCX],[
                          OPAL_CHECK_PACKAGE([ompi_check_ucx],
                                             [ucp/api/ucp.h],
                                             [ucp],
-                                            [ucp_ep_flush_nb],
+                                            [ucp_cleanup],
                                             [],
                                             [$ompi_check_ucx_dir],
                                             [$ompi_check_ucx_libdir],
@@ -108,6 +108,18 @@ AC_DEFUN([OMPI_CHECK_UCX],[
                                  [AC_DEFINE([HAVE_UCP_TAG_SEND_NBR],[1],
                                             [have ucp_tag_send_nbr()])], [],
                                  [#include <ucp/api/ucp.h>])
+                  AC_CHECK_DECLS([ucp_ep_flush_nb],
+                                 [AC_DEFINE([HAVE_UCP_EP_FLUSH_NB],[1],
+                                            [have ucp_ep_flush_nb()])], [],
+                                 [#include <ucp/api/ucp.h>])
+                  AC_CHECK_DECLS([ucp_worker_flush_nb],
+                                 [AC_DEFINE([HAVE_UCP_WORKER_FLUSH_NB],[1],
+                                            [have ucp_worker_flush_nb()])], [],
+                                 [#include <ucp/api/ucp.h>])
+                  AC_CHECK_DECLS([ucp_request_check_status],
+                                 [AC_DEFINE([HAVE_UCP_REQUEST_CHECK_STATUS],[1],
+                                            [have ucp_request_check_status()])], [],
+                                 [#include <ucp/api/ucp.h>])
                   CPPFLAGS=$old_CPPFLAGS
 
                   OPAL_SUMMARY_ADD([[Transports]],[[Open UCX]],[$1],[$ompi_check_ucx_happy])])])

opal/mca/common/ucx/common_ucx.h

@@ -33,6 +33,9 @@ ucs_status_t opal_common_ucx_wait_request(ucs_status_ptr_t request, ucp_worker_h
 {
     ucs_status_t status;
     int i;
+#ifndef HAVE_UCP_REQUEST_CHECK_STATUS
+    ucp_tag_recv_info_t info;
+#endif
 
     /* check for request completed or failed */
     if (OPAL_LIKELY(UCS_OK == request)) {
@@ -44,7 +47,13 @@ ucs_status_t opal_common_ucx_wait_request(ucs_status_ptr_t request, ucp_worker_h
     while (1) {
         /* call UCX progress */
         for (i = 0; i < opal_common_ucx_progress_iterations; i++) {
-            if (UCS_INPROGRESS != (status = ucp_request_check_status(request))) {
+            if (UCS_INPROGRESS != (status =
+#if HAVE_UCP_REQUEST_CHECK_STATUS
+                ucp_request_check_status(request)
+#else
+                ucp_request_test(request, &info)
+#endif
+                )) {
                 ucp_request_free(request);
                 return status;
             }
@@ -59,19 +68,27 @@ ucs_status_t opal_common_ucx_wait_request(ucs_status_ptr_t request, ucp_worker_h
 static inline
 ucs_status_t opal_common_ucx_ep_flush(ucp_ep_h ep, ucp_worker_h worker)
 {
+#if HAVE_UCP_EP_FLUSH_NB
     ucs_status_ptr_t status;
 
     status = ucp_ep_flush_nb(ep, 0, opal_common_ucx_empty_complete_cb);
     return opal_common_ucx_wait_request(status, worker);
+#else
+    return ucp_ep_flush(ep);
+#endif
 }
 
 static inline
 ucs_status_t opal_common_ucx_worker_flush(ucp_worker_h worker)
 {
+#if HAVE_UCP_WORKER_FLUSH_NB
     ucs_status_ptr_t status;
 
     status = ucp_worker_flush_nb(worker, 0, opal_common_ucx_empty_complete_cb);
     return opal_common_ucx_wait_request(status, worker);
+#else
+    return ucp_worker_flush(worker);
+#endif
 }
 
 static inline