[LTP] [PATCH 12/16] controllers: Update memcg_stress_test to use newer cgroup lib

[Luke Nowakowski-Krijger]

Update the test to use the newer cgroup lib which enables the testing of
both v1 and v2 memory controllers and makes the setup and cleanup much
simpler.

Signed-off-by: Luke Nowakowski-Krijger <luke.nowakowskikrijger@canonical.com>
---
 .../memcg/stress/memcg_stress_test.sh         | 32 +++++++------------
 1 file changed, 12 insertions(+), 20 deletions(-)

diff --git a/testcases/kernel/controllers/memcg/stress/memcg_stress_test.sh b/testcases/kernel/controllers/memcg/stress/memcg_stress_test.sh
index c43d72116..daed24b2c 100755
--- a/testcases/kernel/controllers/memcg/stress/memcg_stress_test.sh
+++ b/testcases/kernel/controllers/memcg/stress/memcg_stress_test.sh
@@ -23,10 +23,16 @@ TST_TIMEOUT=2100
 
 setup()
 {
-	if ! is_cgroup_subsystem_available_and_enabled "memory"; then
-		tst_brk TCONF "Either kernel does not support Memory Resource Controller or feature not enabled"
+	cgroup_require "memory"
+	cgroup_v=$(cgroup_get_version "memory")
+	test_path=$(cgroup_get_test_path "memory")
+	task_list=$(cgroup_get_task_list "memory")
+	if [ "$cgroup_v" = "V2" ]; then
+			ROD echo "+memory" > "$test_path/cgroup.subtree_control"
 	fi
 
+	tst_res TINFO "test starts with cgroup $cgroup_v"
+
 	echo 3 > /proc/sys/vm/drop_caches
 	sleep 2
 	local mem_free=`cat /proc/meminfo | grep MemFree | awk '{ print $2 }'`
@@ -43,18 +49,7 @@ setup()
 
 cleanup()
 {
-	if [ -e /dev/memcg ]; then
-		EXPECT_PASS umount /dev/memcg
-		EXPECT_PASS rmdir /dev/memcg
-	fi
-}
-
-do_mount()
-{
-	cleanup
-
-	EXPECT_PASS mkdir /dev/memcg
-	EXPECT_PASS mount -t cgroup -omemory memcg /dev/memcg
+	cgroup_cleanup
 }
 
 # $1 Number of cgroups
@@ -71,13 +66,11 @@ run_stress()
 
 	tst_res TINFO "Testing $cgroups cgroups, using $mem_size MB, interval $interval"
 
-	do_mount
-
 	tst_res TINFO "Starting cgroups"
 	for i in $(seq 0 $(($cgroups-1))); do
-		mkdir /dev/memcg/$i 2> /dev/null
+		ROD mkdir "$test_path/$i"
 		memcg_process_stress $mem_size $interval &
-		echo $! > /dev/memcg/$i/tasks
+		ROD echo $! > "$test_path/$i/$task_list"
 		pids="$pids $!"
 	done
 
@@ -93,12 +86,11 @@ run_stress()
 	for pid in $pids; do
 		kill -KILL $pid 2> /dev/null
 		wait $pid 2> /dev/null
-		rmdir /dev/memcg/$i 2> /dev/null
+		ROD rmdir "$test_path/$i"
 		i=$((i+1))
 	done
 
 	tst_res TPASS "Test passed"
-	cleanup
 }
 
 test1()
-- 
2.32.0