From 41b4dc14ee807cb1bd15e67cad287534046f92dc Mon Sep 17 00:00:00 2001 From: Joonsoo Kim Date: Tue, 11 Aug 2020 18:37:34 -0700 Subject: mm/gup: restrict CMA region by using allocation scope API We have well defined scope API to exclude CMA region. Use it rather than manipulating gfp_mask manually. With this change, we can now restore __GFP_MOVABLE for gfp_mask like as usual migration target allocation. It would result in that the ZONE_MOVABLE is also searched by page allocator. For hugetlb, gfp_mask is redefined since it has a regular allocation mask filter for migration target. __GPF_NOWARN is added to hugetlb gfp_mask filter since a new user for gfp_mask filter, gup, want to be silent when allocation fails. Note that this can be considered as a fix for the commit 9a4e9f3b2d73 ("mm: update get_user_pages_longterm to migrate pages allocated from CMA region"). However, "Fixes" tag isn't added here since it is just suboptimal but it doesn't cause any problem. Suggested-by: Michal Hocko Signed-off-by: Joonsoo Kim Signed-off-by: Andrew Morton Acked-by: Vlastimil Babka Cc: Christoph Hellwig Cc: Roman Gushchin Cc: Mike Kravetz Cc: Naoya Horiguchi Cc: "Aneesh Kumar K . V" Link: http://lkml.kernel.org/r/1596180906-8442-1-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Linus Torvalds --- mm/gup.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) (limited to 'mm/gup.c') diff --git a/mm/gup.c b/mm/gup.c index d8a33dd1430d..6c20c6e37635 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1620,10 +1620,12 @@ static struct page *new_non_cma_page(struct page *page, unsigned long private) * Trying to allocate a page for migration. Ignore allocation * failure warnings. We don't force __GFP_THISNODE here because * this node here is the node where we have CMA reservation and - * in some case these nodes will have really less non movable + * in some case these nodes will have really less non CMA * allocation memory. + * + * Note that CMA region is prohibited by allocation scope. */ - gfp_t gfp_mask = GFP_USER | __GFP_NOWARN; + gfp_t gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_NOWARN; if (PageHighMem(page)) gfp_mask |= __GFP_HIGHMEM; @@ -1631,6 +1633,8 @@ static struct page *new_non_cma_page(struct page *page, unsigned long private) #ifdef CONFIG_HUGETLB_PAGE if (PageHuge(page)) { struct hstate *h = page_hstate(page); + + gfp_mask = htlb_modify_alloc_mask(h, gfp_mask); /* * We don't want to dequeue from the pool because pool pages will * mostly be from the CMA region. @@ -1645,11 +1649,6 @@ static struct page *new_non_cma_page(struct page *page, unsigned long private) */ gfp_t thp_gfpmask = GFP_TRANSHUGE | __GFP_NOWARN; - /* - * Remove the movable mask so that we don't allocate from - * CMA area again. - */ - thp_gfpmask &= ~__GFP_MOVABLE; thp = __alloc_pages_node(nid, thp_gfpmask, HPAGE_PMD_ORDER); if (!thp) return NULL; @@ -1795,7 +1794,6 @@ static long __gup_longterm_locked(struct task_struct *tsk, vmas_tmp, NULL, gup_flags); if (gup_flags & FOLL_LONGTERM) { - memalloc_nocma_restore(flags); if (rc < 0) goto out; @@ -1808,9 +1806,10 @@ static long __gup_longterm_locked(struct task_struct *tsk, rc = check_and_migrate_cma_pages(tsk, mm, start, rc, pages, vmas_tmp, gup_flags); +out: + memalloc_nocma_restore(flags); } -out: if (vmas_tmp != vmas) kfree(vmas_tmp); return rc; -- cgit v1.2.3