Dave Hansen <dave.hansen@xxxxxxxxx> writes:
> On 6/19/21 1:18 AM, Huang, Ying wrote:
>>>> int next_demotion_node(int node)
>>>> {
>>>> - return node_demotion[node];
>>>> + /*
>>>> + * node_demotion[] is updated without excluding
>>>> + * this function from running. READ_ONCE() avoids
>>>> + * reading multiple, inconsistent 'node' values
>>>> + * during an update.
>>>> + */
>>>> + return READ_ONCE(node_demotion[node]);
>>>> }
>>> Is it necessary to have two separate patches to add node_demotion and
>>> next_demotion_node() then modify it immediately? Maybe merge Patch 1 into 2?
>>>
>>> Hmm, I just checked Patch 3 and it changes node_demotion again and uses RCU.
>>> I guess it might be much simpler to just introduce node_demotion with RCU
>>> in this patch and Patch 3 only takes care of hotplug events.
>> Hi, Dave,
>>
>> What do you think about this?
>>
>
> Squashing them seems like a good idea to me.
Sure. Will do that. How about move RCU from 3/10 to the squashed one?
Best Regards,
Huang, Ying
