Hi. I'd like this proc_cgroup_show de-contention. (Provided the previous patch and this one can be worked out somehow.) On Tue, Oct 17, 2023 at 12:45:39PM +0000, Yafang Shao <laoar.shao@xxxxxxxxx> wrote: > They can ran successfully after implementing this change, with no RCU > warnings in dmesg. It's worth noting that this change can also catch > deleted cgroups, as demonstrated by running the following task at the > same time: Can those be other than v1 root cgroups? A suffix "(unmounted)" may be more informative then. (Non-zombie tasks prevent their cgroup removal, zombie tasks won't have any non-trivial path rendered.) > @@ -6256,7 +6256,7 @@ int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns, > if (!buf) > goto out; > > - cgroup_lock(); > + rcu_read_lock(); What about the cgroup_path_ns_locked() that prints the path? (I argue above that no non-trivial path is rendered but I'm not sure whether rcu_read_lock() is sufficient sync wrt cgroup rmdir.)
Attachment:
signature.asc
Description: PGP signature
