Set UCT parameters from UCP API

[changchengx]

Backport below PR from master to integration3 branch
openucx#7019

Signed-off-by: Changcheng Liu jerrliu@nvidia.com

[changchengx]

Example:
Default IB_RX_QUEUE_LEN under transports

[jerrliu@gen-l-vrt-307 ucx]$ ./install/bin/ucx_info -c | grep 'RX_QUEUE_LEN\>'
UCX_RC_VERBS_RX_QUEUE_LEN=4095
UCX_RC_MLX5_RX_QUEUE_LEN=4095
UCX_DC_MLX5_RX_QUEUE_LEN=4095
UCX_UD_VERBS_RX_QUEUE_LEN=4096
UCX_UD_MLX5_RX_QUEUE_LEN=4096

call ucp_config_modify to cached the right UCT configurations

[jerrliu@gen-l-vrt-307 ucx]$ git diff
diff --git a/test/examples/ucp_hello_world.c b/test/examples/ucp_hello_world.c
index 032f4b15d..d3c5e6412 100644
--- a/test/examples/ucp_hello_world.c
+++ b/test/examples/ucp_hello_world.c
@@ -465,6 +465,8 @@ int main(int argc, char **argv)
     status = ucp_config_read(NULL, NULL, &config);
     CHKERR_JUMP(status != UCS_OK, "ucp_config_read\n", err);
 
+    ucp_config_modify(config, "IB_RX_QUEUE_LEN", "8192");
+
     ucp_params.field_mask   = UCP_PARAM_FIELD_FEATURES |
                               UCP_PARAM_FIELD_REQUEST_SIZE |
                               UCP_PARAM_FIELD_REQUEST_INIT;

Print the cached UCT configuration

[jerrliu@gen-l-vrt-307 ucx]$ stdbuf -o0 ./test/examples/ucp_hello_world  | grep 'IB_RX_QUEUE_LEN=8192'
IB_RX_QUEUE_LEN=8192

Below log shows that the cached right UCT configurations are applied

[jerrliu@gen-l-vrt-307 ucx]$ UCX_LOG_LEVEL=Debug stdbuf -o0 ./test/examples/ucp_hello_world  | grep 'apply uct configuration'
INFO: UCP_HELLO_WORLD mode = 0 server = (null) port = 13337
[1632638434.130861] [gen-l-vrt-307:1173892:0]    ucp_context.c:495  UCX  DEBUG apply uct configuration IB_RX_QUEUE_LEN=8192
[1632638434.136542] [gen-l-vrt-307:1173892:0]    ucp_context.c:495  UCX  DEBUG apply uct configuration IB_RX_QUEUE_LEN=8192
[1632638434.144211] [gen-l-vrt-307:1173892:0]    ucp_context.c:495  UCX  DEBUG apply uct configuration IB_RX_QUEUE_LEN=8192
[1632638434.185955] [gen-l-vrt-307:1173892:0]    ucp_context.c:495  UCX  DEBUG apply uct configuration IB_RX_QUEUE_LEN=8192
[1632638434.197096] [gen-l-vrt-307:1173892:0]    ucp_context.c:495  UCX  DEBUG apply uct configuration IB_RX_QUEUE_LEN=8192

call ucp_config_modify to cached the wrong UCT configurations

[jerrliu@gen-l-vrt-307 ucx]$ git diff
diff --git a/test/examples/ucp_hello_world.c b/test/examples/ucp_hello_world.c
index 032f4b15d..0e1612484 100644
--- a/test/examples/ucp_hello_world.c
+++ b/test/examples/ucp_hello_world.c
@@ -465,6 +465,8 @@ int main(int argc, char **argv)
     status = ucp_config_read(NULL, NULL, &config);
     CHKERR_JUMP(status != UCS_OK, "ucp_config_read\n", err);
 
+    ucp_config_modify(config, "NOEXISTED_UCT_KEY", "dummy_val");
+
     ucp_params.field_mask   = UCP_PARAM_FIELD_FEATURES |
                               UCP_PARAM_FIELD_REQUEST_SIZE |
                               UCP_PARAM_FIELD_REQUEST_INIT;

Below log shows that the cached wrong UCT configurations are not applied

[jerrliu@gen-l-vrt-307 ucx]$ stdbuf -o0 ./test/examples/ucp_hello_world -n 192.168.30.6 2>&1 | grep 'unused cached uct'
[1632798667.496143] [gen-l-vrt-307:1401205:0]     ucp_worker.c:1687 UCX  WARN  unused cached uct configuration: NOEXISTED_UCT_KEY

Note: the warning could only be called at the end of ucp_worker_create

[changchengx]

@yosefe This is the PR to set UCT configurations through UCP API and it's required by customers.