In the current cgroup1 environment, associating operations between a cgroup and applications in a BPF program requires storing a mapping of cgroup_id to application either in a hash map or maintaining it in userspace. However, by enabling bpf_cgrp_storage for cgroup1, it becomes possible to conveniently store application-specific information in cgroup-local storage and utilize it within BPF programs. Furthermore, enabling this feature for cgroup1 involves minor modifications for the non-attach case, streamlining the process. However, when it comes to enabling this functionality for the cgroup1 attach case, it presents challenges. Therefore, the decision is to focus on enabling it solely for the cgroup1 non-attach case at present. If attempting to attach to a cgroup1 fd, the operation will simply fail with the error code -EBADF. Changes: - RFC -> v1: - Collect acked-by - Avoid unnecessary is_cgroup1 check (Yonghong) - Keep the code patterns consistent (Yonghong) Yafang Shao (3): bpf: Enable bpf_cgrp_storage for cgroup1 non-attach case selftests/bpf: Add a new cgroup helper open_classid() selftests/bpf: Add selftests for cgroup1 local storage kernel/bpf/bpf_cgrp_storage.c | 6 +- tools/testing/selftests/bpf/cgroup_helpers.c | 16 ++++ tools/testing/selftests/bpf/cgroup_helpers.h | 1 + .../selftests/bpf/prog_tests/cgrp_local_storage.c | 98 +++++++++++++++++++++- .../selftests/bpf/progs/cgrp_ls_recursion.c | 84 +++++++++++++++---- .../selftests/bpf/progs/cgrp_ls_sleepable.c | 61 ++++++++++++-- tools/testing/selftests/bpf/progs/cgrp_ls_tp_btf.c | 82 +++++++++++++----- 7 files changed, 298 insertions(+), 50 deletions(-) -- 1.8.3.1
