Re: [patch 05/19] split LRU lists into anon & file sets

Rik van Riel
2008-01-11T16:16:01Z

On Fri, 11 Jan 2008 10:59:18 -0500
Lee Schermerhorn <Lee.Schermerhorn@hp.com> wrote:

> On Fri, 2008-01-11 at 10:42 -0500, Rik van Riel wrote:
> > On Fri, 11 Jan 2008 15:24:34 +0900
> > KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> wrote:
> >
> > > below patch is a bit cleanup proposal.
> > > i think LRU_FILE is more clarify than "/2".
> > >
> > > What do you think it?
> >
> > Thank you for the cleanup, your version looks a lot nicer.
> > I have applied your patch to my series.
> >
>
> Rik:
>
> I think we also want to do something like:
>
> - BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3);
> + BUILD_BUG_ON(LRU_INACTIVE_FILE != 2 || LRU_ACTIVE_FILE != 3 ||
> + NR_LRU_LISTS > 6);
>
> Then we'll be warned if future change might break our implicit
> assumption that any lru_list value with '0x2' set is a file lru.

Restoring the code to your original version makes things work again.

OTOH, I almost wonder if we should not simply define it to

return (l == LRU_INACTIVE_FILE || l == LRU_ACTIVE_FILE)

and just deal with it.

Your version of the code is correct and probably faster, but not as
easy to read and probably not in a hot path :)

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