On Fri, Mar 19, 2010 at 04:27:32PM +0900, KAMEZAWA Hiroyuki wrote: > On Fri, 19 Mar 2010 16:10:23 +0900 > KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> wrote: > > > On Fri, 19 Mar 2010 15:26:36 +0900 > > Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> wrote: > > > > > When we look into pagemap using page-types with option -p, the value > > > of pfn for hugepages looks wrong (see below.) > > > This is because pte was evaluated only once for one vma > > > although it should be updated for each hugepage. This patch fixes it. > > > > > > $ page-types -p 3277 -Nl -b huge > > > voffset offset len flags > > > 7f21e8a00 11e400 1 ___U___________H_G________________ > > > 7f21e8a01 11e401 1ff ________________TG________________ > > > 7f21e8c00 11e400 1 ___U___________H_G________________ > > > 7f21e8c01 11e401 1ff ________________TG________________ > > > ^^^ > > > should not be the same > > > > > > With this patch applied: > > > > > > $ page-types -p 3386 -Nl -b huge > > > voffset offset len flags > > > 7fec7a600 112c00 1 ___UD__________H_G________________ > > > 7fec7a601 112c01 1ff ________________TG________________ > > > 7fec7a800 113200 1 ___UD__________H_G________________ > > > 7fec7a801 113201 1ff ________________TG________________ > > > ^^^ > > > OK > > > > > Hmm. Is this bug ? To me, it's just shown in hugepage's pagesize, by design. > > > I'm sorry it seems this is bugfix. > > But, this means hugeltb_entry() is not called per hugetlb entry...isn't it ? > Correct. Hugetlb_entry() is called per vma. > Why hugetlb_entry() cannot be called per hugeltb entry ? Don't we need a code > for a case as pmd_size != hugetlb_size in walk_page_range() for generic fix ? > Because in some architecture there is no generic means to know whether a pgd/pmd/pud/pte is hugetlb entry or not. For second question, vma-based walking is generic solution and works for "pmd_size != hugetlb_size" case. Thanks, Naoya Horiguchi -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>