openmpi: add libfabric support (for omnipath networks)

pkgs/development/libraries/openmpi/default.nix

@@ -1,5 +1,6 @@
 { stdenv, fetchurl, fetchpatch, gfortran, perl, libnl
 , rdma-core, zlib, numactl, libevent, hwloc, pkgsTargetTarget, symlinkJoin
+, libpsm2, libfabric
 
 # Enable CUDA support
 , cudaSupport ? false, cudatoolkit ? null
@@ -9,6 +10,10 @@
 
 # Pass PATH/LD_LIBRARY_PATH to point to current mpirun by default
 , enablePrefix ? false
+
+# Enable libfabric support (necessary for Omnipath networks) on x86_64 linux
+, fabricSupport ? stdenv.isLinux && stdenv.isx86_64
+
 }:
 
 assert !cudaSupport || cudatoolkit != null;
@@ -44,7 +49,8 @@ in stdenv.mkDerivation rec {
     ++ lib.optionals isLinux [ libnl numactl ]
     ++ lib.optionals cudaSupport [ cudatoolkit ]
     ++ [ libevent hwloc ]
-    ++ lib.optional (isLinux || isFreeBSD) rdma-core;
+    ++ lib.optional (isLinux || isFreeBSD) rdma-core
+    ++ lib.optional fabricSupport [ libpsm2 libfabric ];
 
   nativeBuildInputs = [ perl ];
 
@@ -56,6 +62,7 @@ in stdenv.mkDerivation rec {
     # https://github.com/openucx/ucx
     # https://www.open-mpi.org/faq/?category=buildcuda
     ++ lib.optionals cudaSupport [ "--with-cuda=${cudatoolkit_joined}" "--enable-dlopen" ]
+    ++ lib.optionals fabricSupport [ "--with-psm2=${libpsm2}" "--with-libfabric=${libfabric}" ]
     ;
 
   enableParallelBuilding = true;