On 6/22/24 16:04, Markus Elfring wrote:
…
+++ b/kernel/cgroup/cpuset.c
…
@@ -5051,10 +5066,12 @@ int proc_cpuset_show(struct seq_file *m, struct pid_namespace *ns,
if (!buf)
goto out;
+ mutex_lock(&cpuset_mutex);
css = task_get_css(tsk, cpuset_cgrp_id);
retval = cgroup_path_ns(css->cgroup, buf, PATH_MAX,
current->nsproxy->cgroup_ns);
css_put(css);
+ mutex_unlock(&cpuset_mutex);
…
Under which circumstances would you become interested to apply a statement
like “guard(mutex)(&cpuset_mutex);”?
https://elixir.bootlin.com/linux/v6.10-rc4/source/include/linux/mutex.h#L196
A mutex guard will be more appropriate if there is an error exit case
that needs to be handled. Otherwise, it is more straight forward and
easier to understand with the simple lock/unlock.
Cheers,
Longman
