[PATCH] cgroup: kselftest: Relax fs_spec checks

[Chris Down]

On my laptop most memcg kselftests were being skipped because it claimed
cgroup v2 hierarchy wasn't mounted, but this isn't correct. Instead, it
seems current systemd HEAD mounts it with the name "cgroup2" instead of
"cgroup":

    % grep cgroup /proc/mounts
    cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,noexec,relatime,nsdelegate 0 0

I can't think of a reason to need to check fs_spec explicitly
since it's arbitrary, so we can just rely on fs_vfstype.

After these changes, `make TARGETS=cgroup kselftest` actually runs the
cgroup v2 tests in more cases.

Signed-off-by: Chris Down <chris@xxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Roman Gushchin <guro@xxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: cgroups@xxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Cc: kernel-team@xxxxxx
---
 tools/testing/selftests/cgroup/cgroup_util.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/tools/testing/selftests/cgroup/cgroup_util.c b/tools/testing/selftests/cgroup/cgroup_util.c
index 4c223266299a..bdb69599c4bd 100644
--- a/tools/testing/selftests/cgroup/cgroup_util.c
+++ b/tools/testing/selftests/cgroup/cgroup_util.c
@@ -191,8 +191,7 @@ int cg_find_unified_root(char *root, size_t len)
 		strtok(NULL, delim);
 		strtok(NULL, delim);
 
-		if (strcmp(fs, "cgroup") == 0 &&
-		    strcmp(type, "cgroup2") == 0) {
+		if (strcmp(type, "cgroup2") == 0) {
 			strncpy(root, mount, len);
 			return 0;
 		}
-- 
2.22.0