Re: [PATCH -tip] cpuacct: per-cgroup utime/stime statistics - v5

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

> cpuacct: Add stime and utime statistics
> 
> Add per-cgroup cpuacct controller statistics like the system and user
> time consumed by the group of tasks.

Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>

except a bug below.

> +	for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
> +		if (percpu_counter_init(&ca->cpustat[i], 0))
> +			goto out_free_counters;
>  
>  	if (cgrp->parent)
>  		ca->parent = cgroup_ca(cgrp->parent);
>  
>  	return &ca->css;
> +
> +out_free_counters:
> +	i--;
> +	while (i-- >= 0)
> +		percpu_counter_destroy(&ca->cpustat[i]);

replace "i--; while (i-- >=0)" to "while (--i >=0)", otherwise
you'll be accessing ca->cpustat[-1].

> +	free_percpu(ca->cpuusage);
> +out_free_ca:
> +	kfree(ca);
> +out:
> +	return ERR_PTR(-ENOMEM);
>  }