testsuite: add hwloc GPU Id remapping test

Use a Sierra hwloc xml which has 4 GPUs.

Get a nested allocation using flux mini alloc
with 2 GPUs and run
  - flux ion-resource ns-info 0 gpu 0
  - flux ion-resource ns-info 0 gpu 1
to check how the self-discovered GPU
Id 0 and 1 are remapped to.

When we use high Id first match policy,
they should map to 2 and 3 because
the Fluxion scheduler will select GPU 2 and 3
(i.e., CUDA_VISIBLE_DEVICE=2,3 passed into
the nested instance).

Similarly, shen we use low Id first match
policy, they should map to 0 and 1.

t/t1016-nest-namespace.t

@@ -0,0 +1,91 @@
+#!/bin/sh
+
+test_description='Test Id Namespace Remapping for Nested Instances'
+
+. `dirname $0`/sharness.sh
+
+hwloc_basepath=`readlink -e ${SHARNESS_TEST_SRCDIR}/data/hwloc-data`
+# 1 brokers: 1 node, 2 sockets, 44 cores 4 gpus
+excl_1N1B="${hwloc_basepath}/001N/exclusive/01-brokers-sierra2"
+
+export FLUX_SCHED_MODULE=none
+
+test_under_flux 1
+
+test_expect_success 'namespace: load test resources' '
+    load_test_resources ${excl_1N1B}
+'
+
+test_expect_success 'namespace: loading resource and qmanager modules works' '
+    load_resource load-allowlist=cluster,node,gpu,core policy=high &&
+    load_qmanager
+'
+
+test_expect_success 'namespace: gpu id remapping works with hwloc (pol=hi)' '
+    cat >nest.sh <<-EOF &&
+	#!/bin/sh
+	flux module load sched-fluxion-resource load-allowlist=cluster,node,gpu,core
+	flux module load sched-fluxion-qmanager
+	flux resource list
+	flux ion-resource ns-info 0 gpu 0
+	flux ion-resource ns-info 0 gpu 1
+	echo \${CUDA_VISIBLE_DEVICES}
+EOF
+    cat >exp1 <<-EOF &&
+	2
+	3
+	2-3
+EOF
+    chmod u+x nest.sh &&
+    jobid=$(flux mini batch --output=kvs -n1 -N1 -c22 -g2 ./nest.sh) &&
+    flux job wait-event -t10 ${jobid} release &&
+    flux job attach ${jobid} > out1.a &&
+    tail -3 out1.a > out1.a.fin &&
+    diff out1.a.fin exp1
+'
+
+test_expect_success 'namespace: parent CUDA_VISIBLE_DEVICES has no effect' '
+    export CUDA_VISIBLE_DEVICES="0,1,2,3" &&
+    jobid=$(flux mini batch --output=kvs -n1 -N1 -c22 -g2 ./nest.sh) &&
+    flux job wait-event -t10 ${jobid} release &&
+    flux job attach ${jobid} > out1.b &&
+    tail -3 out1.b > out1.b.fin &&
+    diff out1.b.fin exp1
+'
+
+test_expect_success 'namespace: removing resource and qmanager modules' '
+    remove_resource
+'
+
+test_expect_success 'namespace: loading resource and qmanager modules works' '
+    load_resource load-allowlist=cluster,node,gpu,core policy=low &&
+    load_qmanager
+'
+
+test_expect_success 'namespace: gpu id remapping works with hwloc (pol=low)' '
+    cat >exp2 <<-EOF &&
+	0
+	1
+	0-1
+EOF
+    jobid=$(flux mini batch --output=kvs -n1 -N1 -c22 -g2 ./nest.sh) &&
+    flux job wait-event -t10 ${jobid} release &&
+    flux job attach ${jobid} > out2.a &&
+    tail -3 out2.a > out2.a.fin &&
+    diff out2.a.fin exp2
+'
+
+test_expect_success 'namespace: parent CUDA_VISIBLE_DEVICES has no effect' '
+    export CUDA_VISIBLE_DEVICES=-1 &&
+    jobid=$(flux mini batch --output=kvs -n1 -N1 -c22 -g2 ./nest.sh) &&
+    flux job wait-event -t10 ${jobid} release &&
+    flux job attach ${jobid} > out2.b &&
+    tail -3 out2.b > out2.b.fin &&
+    diff out2.b.fin exp2
+'
+
+test_expect_success 'namespace: removing resource and qmanager modules' '
+    remove_resource
+'
+
+test_done