osc/pt2pt: flush pending fragments on lock ack

This commit addresses an issue that can occur in cases where a lot of
fragments are outstanding.

Signed-off-by: Nathan Hjelm <[email protected]>

Author: hjelmn

ompi/mca/osc/pt2pt/osc_pt2pt_frag.c

@@ -117,16 +117,12 @@ static int ompi_osc_pt2pt_flush_active_frag (ompi_osc_pt2pt_module_t *module, om
     return ret;
 }
 
-int ompi_osc_pt2pt_frag_flush_target (ompi_osc_pt2pt_module_t *module, int target)
+int ompi_osc_pt2pt_frag_flush_pending (ompi_osc_pt2pt_module_t *module, int target)
 {
     ompi_osc_pt2pt_peer_t *peer = ompi_osc_pt2pt_peer_lookup (module, target);
     ompi_osc_pt2pt_frag_t *frag;
     int ret = OMPI_SUCCESS;
 
-    OPAL_OUTPUT_VERBOSE((50, ompi_osc_base_framework.framework_output,
-                         "osc pt2pt: frag flush to target target %d. queue fragments: %lu",
-                         target, (unsigned long) opal_list_get_size (&peer->queued_frags)));
-
     /* walk through the pending list and send */
     OPAL_THREAD_LOCK(&peer->lock);
     while (NULL != (frag = ((ompi_osc_pt2pt_frag_t *) opal_list_remove_first (&peer->queued_frags)))) {
@@ -137,11 +133,40 @@ int ompi_osc_pt2pt_frag_flush_target (ompi_osc_pt2pt_module_t *module, int targe
     }
     OPAL_THREAD_UNLOCK(&peer->lock);
 
-    /* XXX -- TODO -- better error handling */
+    return ret;
+}
+
+int ompi_osc_pt2pt_frag_flush_pending_all (ompi_osc_pt2pt_module_t *module)
+{
+    int ret;
+
+    for (int i = 0 ; i < ompi_comm_size (module->comm) ; ++i) {
+        ret = ompi_osc_pt2pt_frag_flush_pending (module, i);
+        if (OPAL_UNLIKELY(OMPI_SUCCESS != ret)) {
+            return ret;
+        }
+    }
+
+    return ret;
+}
+
+int ompi_osc_pt2pt_frag_flush_target (ompi_osc_pt2pt_module_t *module, int target)
+{
+    ompi_osc_pt2pt_peer_t *peer = ompi_osc_pt2pt_peer_lookup (module, target);
+    ompi_osc_pt2pt_frag_t *frag;
+    int ret = OMPI_SUCCESS;
+
+    OPAL_OUTPUT_VERBOSE((50, ompi_osc_base_framework.framework_output,
+                         "osc pt2pt: frag flush to target target %d. queue fragments: %lu",
+                         target, (unsigned long) opal_list_get_size (&peer->queued_frags)));
+
+    ret = ompi_osc_pt2pt_frag_flush_pending (module, target);
     if (OMPI_SUCCESS != ret) {
+        /* XXX -- TODO -- better error handling */
         return ret;
     }
 
+
     /* flush the active frag */
     ret = ompi_osc_pt2pt_flush_active_frag (module, peer);
 

ompi/mca/osc/pt2pt/osc_pt2pt_frag.h

@@ -44,6 +44,8 @@ OBJ_CLASS_DECLARATION(ompi_osc_pt2pt_frag_t);
 int ompi_osc_pt2pt_frag_start(ompi_osc_pt2pt_module_t *module, ompi_osc_pt2pt_frag_t *buffer);
 int ompi_osc_pt2pt_frag_flush_target(ompi_osc_pt2pt_module_t *module, int target);
 int ompi_osc_pt2pt_frag_flush_all(ompi_osc_pt2pt_module_t *module);
+int ompi_osc_pt2pt_frag_flush_pending (ompi_osc_pt2pt_module_t *module, int target);
+int ompi_osc_pt2pt_frag_flush_pending_all (ompi_osc_pt2pt_module_t *module);
 
 static inline int ompi_osc_pt2pt_frag_finish (ompi_osc_pt2pt_module_t *module,
                                               ompi_osc_pt2pt_frag_t* buffer)
@@ -107,7 +109,7 @@ static inline ompi_osc_pt2pt_frag_t *ompi_osc_pt2pt_frag_alloc_non_buffered (omp
  * soon as it is sent. this allows request-based rma fragments to be completed
  * so MPI_Test/MPI_Wait/etc will work as expected.
  */
-static inline int ompi_osc_pt2pt_frag_alloc (ompi_osc_pt2pt_module_t *module, int target,
+static inline int _ompi_osc_pt2pt_frag_alloc (ompi_osc_pt2pt_module_t *module, int target,
                                              size_t request_len, ompi_osc_pt2pt_frag_t **buffer,
                                              char **ptr, bool long_send, bool buffered)
 {
@@ -164,4 +166,23 @@ static inline int ompi_osc_pt2pt_frag_alloc (ompi_osc_pt2pt_module_t *module, in
     return OMPI_SUCCESS;
 }
 
+static inline int ompi_osc_pt2pt_frag_alloc (ompi_osc_pt2pt_module_t *module, int target,
+                                             size_t request_len, ompi_osc_pt2pt_frag_t **buffer,
+                                             char **ptr, bool long_send, bool buffered)
+{
+    int ret;
+
+    do {
+        ret = ompi_osc_pt2pt_frag_alloc (module, target, request_len , buffer, ptr, long_send, buffered);
+        if (OPAL_LIKELY(OMPI_SUCCESS == ret || OMPI_ERR_OUT_OF_RESOURCE != ret)) {
+            break;
+        }
+
+        ompi_osc_pt2pt_frag_flush_pending_all (module);
+        opal_progress ();
+    } while (1);
+
+    return ret;
+}
+
 #endif

ompi/mca/osc/pt2pt/osc_pt2pt_passive_target.c

@@ -819,6 +819,7 @@ void ompi_osc_pt2pt_process_lock_ack (ompi_osc_pt2pt_module_t *module,
     assert (NULL != lock);
 
     ompi_osc_pt2pt_peer_set_eager_active (peer, true);
+    ompi_osc_pt2pt_frag_flush_pending (module, peer->rank);
 
     ompi_osc_pt2pt_sync_expected (lock);
 }