diff --git a/test/nvme/perf/common.sh b/test/nvme/perf/common.sh
index 721cf01f0..4aecb7bfb 100755
--- a/test/nvme/perf/common.sh
+++ b/test/nvme/perf/common.sh
@@ -3,8 +3,7 @@
 function discover_bdevs() {
 	local rootdir=$1
 	local config_file=$2
-	local cfg_type=$3
-	local wait_for_spdk_bdev=${4:-30}
+	local wait_for_spdk_bdev=30
 	local rpc_server=/var/tmp/spdk-discover-bdevs.sock
 
 	if [ ! -e $config_file ]; then
@@ -12,14 +11,10 @@ function discover_bdevs() {
 		return 1
 	fi
 
-	if [ -z $cfg_type ]; then
-		cfg_type="-c"
-	fi
-
 	# Start the bdev service to query for the list of available
 	# bdevs.
 	$rootdir/test/app/bdev_svc/bdev_svc -r $rpc_server -i 0 \
-		$cfg_type $config_file &> /dev/null &
+		--json $config_file &> /dev/null &
 	stubpid=$!
 	while ! [ -e /var/run/spdk_bdev0 ]; do
 		# If this counter drops to zero, errexit will be caught to abort the test
@@ -135,7 +130,7 @@ function get_numa_node() {
 		done
 	elif [[ "$plugin" =~ "bdev" ]]; then
 		local bdevs
-		bdevs=$(discover_bdevs $rootdir $testdir/bdev.conf --json)
+		bdevs=$(discover_bdevs $rootdir $testdir/bdev.conf)
 		for name in $disks; do
 			local bdev_bdf
 			bdev_bdf=$(jq -r ".[] | select(.name==\"$name\").driver_specific.nvme.pci_address" <<< $bdevs)