selftests/bpf: Add test for using css_task iter in sleepable progs

This Patch add a test to prove css_task iter can be used in normal
sleepable progs.

Signed-off-by: Chuyi Zhou <zhouchuyi@bytedance.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20231031050438.93297-4-zhouchuyi@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/iters.c b/tools/testing/selftests/bpf/prog_tests/iters.c
index c2425791c9232f96b9430ef59058b88ee5cece7a..bf84d4a1d9ae2c68ceeac9f25373fd9df01b6935 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/iters.c
+++ b/tools/testing/selftests/bpf/prog_tests/iters.c
@@ -294,6 +294,7 @@ void test_iters(void)
        RUN_TESTS(iters_state_safety);
        RUN_TESTS(iters_looping);
        RUN_TESTS(iters);
+       RUN_TESTS(iters_css_task);
 
        if (env.has_testmod)
                RUN_TESTS(iters_testmod_seq);

diff --git a/tools/testing/selftests/bpf/progs/iters_css_task.c b/tools/testing/selftests/bpf/progs/iters_css_task.c
index 384ff806990fa799b10ef134fddee124f9c601df..e180aa1b1d52fc8375400581e7f9d7f5f3fdd234 100644 (file)
--- a/tools/testing/selftests/bpf/progs/iters_css_task.c
+++ b/tools/testing/selftests/bpf/progs/iters_css_task.c
@@ -89,3 +89,22 @@ int cgroup_id_printer(struct bpf_iter__cgroup *ctx)
        bpf_cgroup_release(acquired);
        return 0;
 }
+
+SEC("?fentry.s/" SYS_PREFIX "sys_getpgid")
+int BPF_PROG(iter_css_task_for_each_sleep)
+{
+       u64 cgrp_id = bpf_get_current_cgroup_id();
+       struct cgroup *cgrp = bpf_cgroup_from_id(cgrp_id);
+       struct cgroup_subsys_state *css;
+       struct task_struct *task;
+
+       if (cgrp == NULL)
+               return 0;
+       css = &cgrp->self;
+
+       bpf_for_each(css_task, task, css, CSS_TASK_ITER_PROCS) {
+
+       }
+       bpf_cgroup_release(cgrp);
+       return 0;
+}