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Groups > linux.kernel > #1359629
| From | Peter Zijlstra <peterz@infradead.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH v3 3/3] cpuacct: split usage into user_usage and sys_usage |
| Date | 2016-03-17 09:50 +0100 |
| Message-ID | <rdBN0-4Xk-11@gated-at.bofh.it> (permalink) |
| References | <rdxJn-2kC-3@gated-at.bofh.it> <rdxJo-2kC-5@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Thu, Mar 17, 2016 at 12:19:44PM +0800, Zhao Lei wrote:
> +static u64 __cpuusage_read(struct cgroup_subsys_state *css,
> + enum cpuacct_usage_index index)
> {
> struct cpuacct *ca = css_ca(css);
> u64 totalcpuusage = 0;
> int i;
>
> for_each_present_cpu(i)
> + totalcpuusage += cpuacct_cpuusage_read(ca, i, index);
>
> return totalcpuusage;
> }
Ok, so while looking over this, it mostly uses for_each_present_cpu(),
which is already dubious, but then cpuacct_stats_show() uses
for_each_online_cpu().
Why is this? Why not always for_each_possible_cpu()?
Surely, if you offline a cpu, you still want its stat to be included in
your totals, otherwise your numbers will go backwards when you take a
cpu offline.
Could you double check the logic and maybe fix?
Thanks!
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[PATCH v3 3/3] cpuacct: split usage into user_usage and sys_usage Zhao Lei <zhaolei@cn.fujitsu.com> - 2016-03-17 05:30 +0100
Re: [PATCH v3 3/3] cpuacct: split usage into user_usage and sys_usage Peter Zijlstra <peterz@infradead.org> - 2016-03-17 09:50 +0100
RE: [PATCH v3 3/3] cpuacct: split usage into user_usage and sys_usage Zhao Lei <zhaolei@cn.fujitsu.com> - 2016-03-17 10:50 +0100
Re: [PATCH v3 3/3] cpuacct: split usage into user_usage and sys_usage Peter Zijlstra <peterz@infradead.org> - 2016-03-17 11:20 +0100
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