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. > > _And_, Doesn't this patch change behavior of walk_pagemap_range() implicitly ? > No influence to other users ? (as memcontrol.c. in mmotm. Ask Nishimura-san ;) > >From the view point of memcg, this change in walk_pagemap_range() has no influence, because memcg does "if (is_vm_hugetlb_page(vma)) break" before calling walk_pagemap_range(). But we must check other callers too. Thanks, Daisuke Nishimura. -- 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>