[PATCH v5 08/11] mm: hwpoison: soft offline supports thp migration

[Zi Yan]

From: Naoya Horiguchi <n-horigu...@ah.jp.nec.com>

This patch enables thp migration for soft offline.

Signed-off-by: Naoya Horiguchi <n-horigu...@ah.jp.nec.com>

ChangeLog: v1 -> v5:
- fix page isolation counting error

Signed-off-by: Zi Yan <zi....@cs.rutgers.edu>
---
 mm/memory-failure.c | 35 ++++++++++++++---------------------
 1 file changed, 14 insertions(+), 21 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 9b77476ef31f..23ff02eb3ed4 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1481,7 +1481,17 @@ static struct page *new_page(struct page *p, unsigned 
long private, int **x)
        if (PageHuge(p))
                return alloc_huge_page_node(page_hstate(compound_head(p)),
                                                   nid);
-       else
+       else if (thp_migration_supported() && PageTransHuge(p)) {
+               struct page *thp;
+
+               thp = alloc_pages_node(nid,
+                       (GFP_TRANSHUGE | __GFP_THISNODE) & ~__GFP_RECLAIM,
+                       HPAGE_PMD_ORDER);
+               if (!thp)
+                       return NULL;
+               prep_transhuge_page(thp);
+               return thp;
+       } else
                return __alloc_pages_node(nid, GFP_HIGHUSER_MOVABLE, 0);
 }
 
@@ -1665,8 +1675,8 @@ static int __soft_offline_page(struct page *page, int 
flags)
                 * cannot have PAGE_MAPPING_MOVABLE.
                 */
                if (!__PageMovable(page))
-                       inc_node_page_state(page, NR_ISOLATED_ANON +
-                                               page_is_file_cache(page));
+                       mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON +
+                                               page_is_file_cache(page), 
hpage_nr_pages(page));
                list_add(&page->lru, &pagelist);
                ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
                                        MIGRATE_SYNC, MR_MEMORY_FAILURE);
@@ -1689,28 +1699,11 @@ static int __soft_offline_page(struct page *page, int 
flags)
 static int soft_offline_in_use_page(struct page *page, int flags)
 {
        int ret;
-       struct page *hpage = compound_head(page);
-
-       if (!PageHuge(page) && PageTransHuge(hpage)) {
-               lock_page(hpage);
-               if (!PageAnon(hpage) || unlikely(split_huge_page(hpage))) {
-                       unlock_page(hpage);
-                       if (!PageAnon(hpage))
-                               pr_info("soft offline: %#lx: non anonymous 
thp\n", page_to_pfn(page));
-                       else
-                               pr_info("soft offline: %#lx: thp split 
failed\n", page_to_pfn(page));
-                       put_hwpoison_page(hpage);
-                       return -EBUSY;
-               }
-               unlock_page(hpage);
-               get_hwpoison_page(page);
-               put_hwpoison_page(hpage);
-       }
 
        if (PageHuge(page))
                ret = soft_offline_huge_page(page, flags);
        else
-               ret = __soft_offline_page(page, flags);
+               ret = __soft_offline_page(compound_head(page), flags);
 
        return ret;
 }
-- 
2.11.0