On 7/18/19 11:44 PM, Andrew Morton wrote: > On Wed, 19 Jun 2019 09:28:42 -0700 Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx> wrote: > >>> Sorry for replying rather late, and not in the v2 thread, but unlike >>> Hugh I'm not convinced that we should include vma size/alignment in the >>> test for reporting THPeligible, which was supposed to reflect >>> administrative settings and madvise hints. I guess it's mostly a matter >>> of personal feeling. But one objective distinction is that the admin >>> settings and madvise do have an exact binary result for the whole VMA, >>> while this check is more fuzzy - only part of the VMA's span might be >>> properly sized+aligned, and THPeligible will be 1 for the whole VMA. >> >> I think THPeligible is used to tell us if the vma is suitable for >> allocating THP. Both anonymous and shmem THP checks vma size/alignment >> to decide to or not to allocate THP. >> >> And, if vma size/alignment is not checked, THPeligible may show "true" >> for even 4K mapping. This doesn't make too much sense either. > > This discussion seems rather inconclusive. I'll merge up the patchset > anyway. Vlastimil, if you think some changes are needed here then > please let's get them sorted out over the next few weeks? Well, Hugh did ack it, albeit without commenting on this part. I don't feel strongly enough about this for a nack.
