Re: [PATCH 1/2] Traffic control cgroups subsystem

[Li Zefan <lizf@cn.fujitsu.com>]

> +static unsigned int cgroup_tc_classid(struct task_struct *tsk)
> +{
> +	unsigned int tc_classid;
> +
> +	rcu_read_lock();
> +	tc_classid =  container_of(task_subsys_state(tsk, tc_subsys_id),

trivial: 2 spaces   ^^

> +					 struct tc_cgroup, css)->classid;
> +	rcu_read_unlock();
> +	return tc_classid;
> +}
> +

...

> +static int tc_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 val)
> +{
> +	struct tc_cgroup *tc = cgroup_to_tc(cgrp);
> +
> +	cgroup_lock();
> +	if (cgroup_is_removed(cgrp)) {
> +		cgroup_unlock();
> +		return -ENODEV;
> +	}
> +

You may use cgroup_lock_live_group():

	if (cgroup_lock_live_group(cgrp0))
		return -ENODEV;

> +	tc->classid = (unsigned int) (val & 0xffffffff);
> +	cgroup_unlock();
> +	return 0;
> +}
> +
> +static u64 tc_read_u64(struct cgroup *cont, struct cftype *cft)

'cont', 'cgrp' and 'cgroup' are used, it's better to make it consistent
to use 'cgrp' (or 'cgroup') only.

> +{
> +	struct tc_cgroup *tc = cgroup_to_tc(cont);
> +	return tc->classid;
> +}