Merge pull request #2412 from lifubang/removecgpath

remove cgroup path recursively in cgroup v2

tests/integration/delete.bats

@@ -51,3 +51,58 @@ function teardown() {
   runc delete --force notexists
   [ "$status" -eq 0 ]
 }
+
+@test "runc delete --force in cgroupv2 with subcgroups" {
+  requires cgroups_v2 root
+  set_cgroups_path "$BUSYBOX_BUNDLE"
+
+  # grant `rw` priviledge to `/sys/fs/cgroup`
+  cat "${BUSYBOX_BUNDLE}/config.json"\
+   | jq '.mounts |= map((select(.type=="cgroup") | .options -= ["ro"]) // .)'\
+   > "${BUSYBOX_BUNDLE}/config.json.tmp"
+  mv "${BUSYBOX_BUNDLE}/config.json"{.tmp,}
+
+  # run busybox detached
+  runc run -d --console-socket $CONSOLE_SOCKET test_busybox
+  [ "$status" -eq 0 ]
+
+  # check state
+  testcontainer test_busybox running
+
+  # create a sub process
+  __runc exec -d test_busybox sleep 1d
+  [ "$status" -eq 0 ]
+
+  # find the pid of sleep
+  pid=$(__runc exec test_busybox ps -a | grep 1d | awk '{print $1}')
+  [[ ${pid} =~ [0-9]+ ]]
+
+  # create subcgroups
+  cat <<EOF > nest.sh
+  cd /sys/fs/cgroup
+  for f in \$(cat cgroup.controllers); do echo +\$f > cgroup.subtree_control; done
+  mkdir foo
+  cd foo
+  echo threaded > cgroup.type
+  echo ${pid} > cgroup.threads
+  cat cgroup.threads
+EOF
+  cat nest.sh | runc exec test_busybox sh
+  [[ ${output} =~ [0-9]+ ]]
+
+  # check create subcgroups success
+  [ -d $CGROUP_PATH/foo ]
+
+  # check cgroup.threads' value
+  runc exec test_busybox cat /sys/fs/cgroup/foo/cgroup.threads
+  [[ ${output} =~ [0-9]+ ]]
+
+  # force delete test_busybox
+  runc delete --force test_busybox
+
+  runc state test_busybox
+  [ "$status" -ne 0 ]
+
+  # check delete subcgroups success
+  [ ! -d $CGROUP_PATH/foo ]
+}