Re: [PATCH] mm: mlock: remove lru_add_drain_all()

From: Shakeel Butt
Date: Thu Oct 19 2017 - 15:46:57 EST


> [...]
>>
>> Sorry for the confusion. I wanted to say that if the pages which are
>> being mlocked are on caches of remote cpus then lru_add_drain_all will
>> move them to their corresponding LRUs and then remaining functionality
>> of mlock will move them again from their evictable LRUs to unevictable
>> LRU.
>
> yes, but the point is that we are draining pages which might be not
> directly related to pages which _will_ be mlocked by the syscall. In
> fact those will stay on the cache. This is the primary reason why this
> draining doesn't make much sense.
>
> Or am I still misunderstanding what you are saying here?
>

lru_add_drain_all() will drain everything irrespective if those pages
are being mlocked or not.