On Thu, Sep 07, 2023 at 11:05:07AM +0800, Yafang Shao wrote: > The fd-based cgroup interface plays a crucial role in BPF programs, > particularly in components such as cgroup_iter, bpf_cgrp_storage, and > cgroup_array maps, as well as in the attachment and detachment of > cgroups. Yeah, I know they're used. It's just that they are inferior identifiers from cgroup's POV as they are ephemeral, can't easily be transferred across process boundaries or persisted beyond the lifetime of the fd-owing process or the cgroups which are being pointed to. Thanks. -- tejun