Hello,
On Thu, Mar 28, 2024 at 02:28:51PM -0700, Alexei Starovoitov wrote:
So filename will be one of cgroup_base_files[].name ? We probably don't want psi or cgroup1_base_files in there.
Would it matter?
Few weak reasons: . cgroup_psi_files have show/write/poll/release which doesn't map to this bpf_cgroup_knob_write/read ? . cgroup1_base_files probably needs to a separate kfunc bpf_cgroup1_...
If the user has root perm, they can do whatever with the files anyway, so I'm not sure why we'd restrict any specific knob. Maybe we wanna make sure @filename doesn't include '/'? Or is it that you don't want to go through the usual file name look up?
yeah. why do a file lookup? The names are there in the array. cgroup pointer gives that "relative path" and knob name is the last part of such "path". Easy to search in that array(s).
Difficult to tell without looking at the implementation but I don't have strong opinions. The interface makes sense to me and as long as we can hook it up in a reasonably way, it should be okay. We can always change internal implementation later if necessary.
Thanks.