Merge pull request #8065 from devreal/fix_spc_mpit

SPC: allow starting through MPI_T without explicitly setting MCA parameter

Author: bosilca

ompi/runtime/ompi_mpi_params.c

@@ -334,21 +334,23 @@ int ompi_mpi_register_params(void)
                                  MCA_BASE_VAR_SCOPE_READONLY,
                                  &ompi_mpi_compat_mpi3);
 
+#if SPC_ENABLE == 1
     ompi_mpi_spc_attach_string = NULL;
     (void) mca_base_var_register("ompi", "mpi", NULL, "spc_attach",
-                                 "A comma delimeted string listing the software-based performance counters (SPCs) to enable.",
+                                 "A comma-delimeted list of software-based performance counters (SPCs) to enable (\"all\" enables all counters).",
                                  MCA_BASE_VAR_TYPE_STRING, NULL, 0, 0,
                                  OPAL_INFO_LVL_4,
                                  MCA_BASE_VAR_SCOPE_READONLY,
                                  &ompi_mpi_spc_attach_string);
 
     ompi_mpi_spc_dump_enabled = false;
     (void) mca_base_var_register("ompi", "mpi", NULL, "spc_dump_enabled",
-                                 "A boolean value for whether (true) or not (false) to enable dumping SPC counters in MPI_Finalize.",
+                                 "A boolean value for whether (true) or not (false) to enable dumping enabled SPC counters in MPI_Finalize.",
                                  MCA_BASE_VAR_TYPE_BOOL, NULL, 0, 0,
                                  OPAL_INFO_LVL_4,
                                  MCA_BASE_VAR_SCOPE_READONLY,
                                  &ompi_mpi_spc_dump_enabled);
+#endif // SPC_ENABLE
 
     return OMPI_SUCCESS;
 }