From 2d0f76c1a28570652c4ae4069425407800f021ca Mon Sep 17 00:00:00 2001
From: Thomas Vegas <tvegas@nvidia.com>
Date: Thu, 23 May 2024 16:22:59 +0300
Subject: [PATCH] Allow get zcopy for smallest sizes

---
 .ci/run_nccl_tests.sh | 3 +--
 src/ucx_uct_lib.c     | 6 ++++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/.ci/run_nccl_tests.sh b/.ci/run_nccl_tests.sh
index 6d094d70..c2724a4f 100755
--- a/.ci/run_nccl_tests.sh
+++ b/.ci/run_nccl_tests.sh
@@ -37,7 +37,6 @@ MPIRUN_OPTIONS_COMMON="\
 -x UCX_MEMTYPE_CACHE=n \
 -x HCOLL_ENABLE_SHARP=0 \
 -x HCOLL_ENABLE_MCAST_ALL=0 \
--x UCX_RC_MLX5_TX_INLINE_RESP=0 \
 -mca pml ucx \
 -mca coll_hcoll_enable 1 \
 --map-by node \
@@ -110,7 +109,7 @@ for TEST_EXE in ${NCCL_TEST_EXE[@]}; do
     #===================
     # Enable ucx_rma tests once this is resolved: https://redmine.mellanox.com/issues/3037941
     # for P2P_LAYER in ucx ucx_rma ib
-    for P2P_LAYER in ucx_uct_read ib ucx_uct ucx; do
+    for P2P_LAYER in ib ucx ucx_uct ucx_uct_read; do
         MPIRUN_OPTIONS_PLUGIN_P2P_LAYER="-x NCCL_PLUGIN_P2P=${P2P_LAYER}"
 
         #===================
diff --git a/src/ucx_uct_lib.c b/src/ucx_uct_lib.c
index cd09d904..3a6441f0 100644
--- a/src/ucx_uct_lib.c
+++ b/src/ucx_uct_lib.c
@@ -46,6 +46,12 @@ static uct_iface_h nccl_uct_resource_iface_open(uct_worker_h worker,
   UCXCHECK(uct_md_iface_config_read(md, tl->tl_name, NULL, NULL, &config),
            return NULL, "read MD iface config for TL '%s'", tl->tl_name);
 
+  if (uct_config_modify(config, "RC_MLX5_TX_INLINE_RESP", "0") != UCS_OK) {
+      WARN("Failed to modify MD configuration for '%s'", tl->tl_name);
+      uct_config_release(config);
+      return NULL;
+  }
+
   params.field_mask =
       UCT_IFACE_PARAM_FIELD_OPEN_MODE | UCT_IFACE_PARAM_FIELD_DEVICE |
       UCT_IFACE_PARAM_FIELD_STATS_ROOT | UCT_IFACE_PARAM_FIELD_RX_HEADROOM;