[PATCH 6/9] mm/z3fold: put z3fold page back into unbuddied list when reclaim or migration fails

[Miaohe Lin]

When doing z3fold page reclaim or migration, the page is removed from
unbuddied list. If reclaim or migration succeeds, it's fine as page is
released. But in case it fails, the page is not put back into unbuddied
list now. The page will be leaked until next compaction work, reclaim
or migration is done.

Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
 mm/z3fold.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/mm/z3fold.c b/mm/z3fold.c
index 5f5d5f1556be..a1c150fc8def 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -1422,6 +1422,8 @@ static int z3fold_reclaim_page(struct z3fold_pool *pool, unsigned int retries)
 			spin_lock(&pool->lock);
 			list_add(&page->lru, &pool->lru);
 			spin_unlock(&pool->lock);
+			if (list_empty(&zhdr->buddy))
+				add_to_unbuddied(pool, zhdr);
 			z3fold_page_unlock(zhdr);
 			clear_bit(PAGE_CLAIMED, &page->private);
 		}
@@ -1638,6 +1640,8 @@ static void z3fold_page_putback(struct page *page)
 	spin_lock(&pool->lock);
 	list_add(&page->lru, &pool->lru);
 	spin_unlock(&pool->lock);
+	if (list_empty(&zhdr->buddy))
+		add_to_unbuddied(pool, zhdr);
 	clear_bit(PAGE_CLAIMED, &page->private);
 	z3fold_page_unlock(zhdr);
 }
-- 
2.23.0