diff --git a/tests/throtl/008 b/tests/throtl/008
index 0570fc0..b1bcf84 100755
--- a/tests/throtl/008
+++ b/tests/throtl/008
@@ -4,76 +4,36 @@
 #
 # Test cgroup iocost IOPS limiting.
 
-. tests/block/rc
-. common/null_blk
-. common/cgroup
+. tests/throtl/rc
 . common/fio
 
 DESCRIPTION="test cgroup iocost controller limits"
 
 requires() {
-	_have_cgroup2_controller io
-	_have_null_blk
 	_have_fio
-	_have_program bc
 	if [[ ! -e "$(_cgroup2_base_dir)/io.cost.qos" ]]; then
 		SKIP_REASONS+=("iocost controller not supported (CONFIG_BLK_CGROUP_IOCOST)")
 		return 1
 	fi
 }
 
+set_conditions() {
+	_set_throtl_blkdev_type "$@"
+}
+
 test() {
 	echo "Running ${TEST_NAME}"
 
-	# Create a null_blk instance
-	local null_blk_params=(
-		blocksize=4096
-		completion_nsec=0
-		memory_backed=0
-		size=1024 # MB
-		submit_queues=1
-		power=1
-	)
-	_init_null_blk nr_devices=0 queue_mode=2 &&
-	if ! _configure_null_blk nullb0 "${null_blk_params[@]}"; then
-		echo "Configuring null_blk failed"
+	# Set up throtl device and cgroup
+	if ! _set_up_throtl; then
 		return 1
 	fi
 
 	local dev_t
-	dev_t=$(</sys/block/nullb0/dev)
+	dev_t=$(</sys/block/"$THROTL_DEV"/dev)
 	if [[ -z $dev_t ]]; then
-		echo "Failed to get major:minor for nullb0"
-		_exit_null_blk
-		return 1
-	fi
-
-	# Initialize cgroups
-	if ! _init_cgroup2; then
-		echo "Initializing cgroup2 failed"
-		_exit_null_blk
-		return 1
-	fi
-
-	# Enable io controller in the subtree
-	local deactivate_io_ctrlr=false
-	if ! grep -wq io "$(_cgroup2_base_dir)/cgroup.subtree_control"; then
-		if ! echo "+io" > "$(_cgroup2_base_dir)/cgroup.subtree_control"; then
-			echo "Failed to enable io controller on cgroup root"
-			_exit_cgroup2
-			_exit_null_blk
-			return 1
-		fi
-		deactivate_io_ctrlr=true
-	fi
-
-	if ! echo "+io" > "$CGROUP2_DIR/cgroup.subtree_control"; then
-		echo "Failed to enable io controller on $CGROUP2_DIR"
-		if [[ $deactivate_io_ctrlr == true ]]; then
-			echo "-io" > "$(_cgroup2_base_dir)/cgroup.subtree_control"
-		fi
-		_exit_cgroup2
-		_exit_null_blk
+		echo "Failed to get major:minor for $THROTL_DEV"
+		_clean_up_throtl
 		return 1
 	fi
 
@@ -81,11 +41,7 @@ test() {
 	# min=100.00 max=100.00 forces vrate to be fixed at 100%
 	if ! echo "$dev_t enable=1 min=100.00 max=100.00" > "$(_cgroup2_base_dir)/io.cost.qos"; then
 		echo "Failed to configure io.cost.qos"
-		if [[ $deactivate_io_ctrlr == true ]]; then
-			echo "-io" > "$(_cgroup2_base_dir)/cgroup.subtree_control"
-		fi
-		_exit_cgroup2
-		_exit_null_blk
+		_clean_up_throtl
 		return 1
 	fi
 
@@ -94,25 +50,21 @@ test() {
 	if ! echo "$dev_t ctrl=user model=linear rbps=0 rseqiops=100 rrandiops=100 wbps=0 wseqiops=10 wrandiops=10" > "$(_cgroup2_base_dir)/io.cost.model"; then
 		echo "Failed to configure io.cost.model"
 		echo "$dev_t enable=0" > "$(_cgroup2_base_dir)/io.cost.qos"
-		if [[ $deactivate_io_ctrlr == true ]]; then
-			echo "-io" > "$(_cgroup2_base_dir)/cgroup.subtree_control"
-		fi
-		_exit_cgroup2
-		_exit_null_blk
+		_clean_up_throtl
 		return 1
 	fi
 
 	# Create a child cgroup for test
 	local cg_name="testgrp"
-	local cg_path="$CGROUP2_DIR/$cg_name"
+	local cg_path="$CGROUP2_DIR/$THROTL_DIR/$cg_name"
 	mkdir "$cg_path"
 
 	# 1. Run FIO read test
 	local -a FIO_PERF_FIELDS
 	FIO_PERF_FIELDS=("read iops")
-	if ! _fio_perf --bs=4k --rw=randread --name=read-test --filename=/dev/nullb0 \
+	if ! _fio_perf --bs=4k --rw=randread --name=read-test --filename=/dev/"$THROTL_DEV" \
 			--ioengine=libaio --direct=1 --iodepth=64 --time_based --runtime=10 \
-			--cgroup="blktests/$cg_name" > /dev/null 2>&1; then
+			--cgroup="blktests/$THROTL_DIR/$cg_name" > /dev/null 2>&1; then
 		echo "FIO read test failed"
 	else
 		local read_iops=${TEST_RUN["read iops"]}
@@ -125,9 +77,9 @@ test() {
 
 	# 2. Run FIO write test
 	FIO_PERF_FIELDS=("write iops")
-	if ! _fio_perf --bs=4k --rw=randwrite --name=write-test --filename=/dev/nullb0 \
+	if ! _fio_perf --bs=4k --rw=randwrite --name=write-test --filename=/dev/"$THROTL_DEV" \
 			--ioengine=libaio --direct=1 --iodepth=64 --time_based --runtime=10 \
-			--cgroup="blktests/$cg_name" > /dev/null 2>&1; then
+			--cgroup="blktests/$THROTL_DIR/$cg_name" > /dev/null 2>&1; then
 		echo "FIO write test failed"
 	else
 		local write_iops=${TEST_RUN["write iops"]}
@@ -140,13 +92,7 @@ test() {
 
 	# Clean up cgroups
 	rmdir "$cg_path"
-	if [[ $deactivate_io_ctrlr == true ]]; then
-		{ echo "-io" > "$(_cgroup2_base_dir)/cgroup.subtree_control"; } &> "${FULL}"
-	fi
-	_exit_cgroup2
-
-	# Clean up null_blk
-	_exit_null_blk
+	_clean_up_throtl
 
 	echo "Test complete"
 }