selftests/bpf: Add a test case for bpf_cgroup_from_id()

Add a test case for bpf_cgroup_from_id.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/Y/bBlt+tPozcQgws@slm.duckdns.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/cgrp_kfunc.c b/tools/testing/selftests/bpf/prog_tests/cgrp_kfunc.c
index b3f7985..adda85f 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/cgrp_kfunc.c
+++ b/tools/testing/selftests/bpf/prog_tests/cgrp_kfunc.c
@@ -84,6 +84,7 @@ static const char * const success_tests[] = {
        "test_cgrp_xchg_release",
        "test_cgrp_get_release",
        "test_cgrp_get_ancestors",
+       "test_cgrp_from_id",
 };
 
 void test_cgrp_kfunc(void)

diff --git a/tools/testing/selftests/bpf/progs/cgrp_kfunc_common.h b/tools/testing/selftests/bpf/progs/cgrp_kfunc_common.h
index 7d30855..2f8de93 100644 (file)
--- a/tools/testing/selftests/bpf/progs/cgrp_kfunc_common.h
+++ b/tools/testing/selftests/bpf/progs/cgrp_kfunc_common.h
@@ -24,6 +24,7 @@ struct cgroup *bpf_cgroup_acquire(struct cgroup *p) __ksym;
 struct cgroup *bpf_cgroup_kptr_get(struct cgroup **pp) __ksym;
 void bpf_cgroup_release(struct cgroup *p) __ksym;
 struct cgroup *bpf_cgroup_ancestor(struct cgroup *cgrp, int level) __ksym;
+struct cgroup *bpf_cgroup_from_id(u64 cgid) __ksym;
 
 static inline struct __cgrps_kfunc_map_value *cgrps_kfunc_map_value_lookup(struct cgroup *cgrp)
 {

diff --git a/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c b/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c
index 0c23ea3..42e13ae 100644 (file)
--- a/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c
+++ b/tools/testing/selftests/bpf/progs/cgrp_kfunc_success.c
@@ -168,3 +168,45 @@ int BPF_PROG(test_cgrp_get_ancestors, struct cgroup *cgrp, const char *path)
 
        return 0;
 }
+
+SEC("tp_btf/cgroup_mkdir")
+int BPF_PROG(test_cgrp_from_id, struct cgroup *cgrp, const char *path)
+{
+       struct cgroup *parent, *res;
+       u64 parent_cgid;
+
+       if (!is_test_kfunc_task())
+               return 0;
+
+       /* @cgrp's ID is not visible yet, let's test with the parent */
+       parent = bpf_cgroup_ancestor(cgrp, cgrp->level - 1);
+       if (!parent) {
+               err = 1;
+               return 0;
+       }
+
+       parent_cgid = parent->kn->id;
+       bpf_cgroup_release(parent);
+
+       res = bpf_cgroup_from_id(parent_cgid);
+       if (!res) {
+               err = 2;
+               return 0;
+       }
+
+       bpf_cgroup_release(res);
+
+       if (res != parent) {
+               err = 3;
+               return 0;
+       }
+
+       res = bpf_cgroup_from_id((u64)-1);
+       if (res) {
+               bpf_cgroup_release(res);
+               err = 4;
+               return 0;
+       }
+
+       return 0;
+}