Re: [PATCH v10 2/9] cpuset: Add new v2 cpuset.sched.domain_root flag

Waiman Long
2018-06-21T08:05:30Z

On 06/21/2018 03:58 PM, Waiman Long wrote:
> On 06/20/2018 10:27 PM, Peter Zijlstra wrote:
>> On Mon, Jun 18, 2018 at 12:14:01PM +0800, Waiman Long wrote:
>>> + cpuset.sched.domain_root
>> Why are we calling this a domain_root and not a partition?
> A partition can consist of several cgroups in a tree structure. That
> flag should only be set at the root of a partition. I will change the
> name to partition_root if you think this name is acceptable.
>
>>> + A read-write single value file which exists on non-root
>>> + cpuset-enabled cgroups. It is a binary value flag that accepts
>>> + either "0" (off) or "1" (on). This flag is set by the parent
>>> + and is not delegatable.
>> You still haven't answered:
>> ,
>> https://lkml.kernel.org/r/20180531094943.GG12180@hirez.programming.kicks-ass.net
>>
>> the question stands.
> I am sorry to miss your question. Turning on domain_root will affects
> the cpu mapping in the parent. That is why it cannot be set by the child
> as a child is not supposed to be able to affect the parent.

After thinking a bit more about it, you are right that I should not use
the term "not delegatable" here. I will rephrase in the next version.

Cheers,
Longman