Hello,
On Fri, Jul 22, 2022 at 05:48:25PM +0000, Yosry Ahmed wrote:
> +
> + /* cgroup_iter walks either the live descendants of a cgroup subtree, or the
> + * ancestors of a given cgroup.
> + */
> + struct {
> + /* Cgroup file descriptor. This is root of the subtree if walking
> + * descendants; it's the starting cgroup if walking the ancestors.
> + * If it is left 0, the traversal starts from the default cgroup v2
> + * root. For walking v1 hierarchy, one should always explicitly
> + * specify the cgroup_fd.
> + */
> + __u32 cgroup_fd;
So, we're identifying the starting point with an fd.
> + __u32 traversal_order;
> + } cgroup;
> };
>
> /* BPF syscall commands, see bpf(2) man-page for more details. */
> @@ -6136,6 +6156,16 @@ struct bpf_link_info {
> __u32 map_id;
> } map;
> };
> + union {
> + struct {
> + __u64 cgroup_id;
> + __u32 traversal_order;
> + } cgroup;
but iterating the IDs. IDs are the better choice for cgroup2 as there's
nothing specific to the calling program or the fds it has, but I guess this
is because you want to use it for cgroup1, right? Oh well, that's okay I
guess.
Acked-by: Tejun Heo <tj@xxxxxxxxxx>
Thanks.
--
tejun
