[PATCH 3/4] mm: thp: remove THP destructor

[Yang Shi <yang.shi@linux.alibaba.com>]

The THP destructor is used to delete THP from per node deferred split
queue, now the operation is moved out of it, so the destructor is not
used anymore, remove it.

Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
---
 include/linux/mm.h | 3 ---
 mm/huge_memory.c   | 6 ------
 mm/page_alloc.c    | 3 ---
 3 files changed, 12 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0e8834a..e543984 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -740,9 +740,6 @@ enum compound_dtor_id {
 #ifdef CONFIG_HUGETLB_PAGE
 	HUGETLB_PAGE_DTOR,
 #endif
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	TRANSHUGE_PAGE_DTOR,
-#endif
 	NR_COMPOUND_DTORS,
 };
 extern compound_page_dtor * const compound_page_dtors[];
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 3307697..50f4720 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -511,7 +511,6 @@ void prep_transhuge_page(struct page *page)
 	 */
 
 	INIT_LIST_HEAD(page_deferred_list(page));
-	set_compound_page_dtor(page, TRANSHUGE_PAGE_DTOR);
 }
 
 static unsigned long __thp_get_unmapped_area(struct file *filp, unsigned long len,
@@ -2818,11 +2817,6 @@ void del_thp_from_deferred_split_queue(struct page *page)
 	}
 }
 
-void free_transhuge_page(struct page *page)
-{
-	free_compound_page(page);
-}
-
 void deferred_split_huge_page(struct page *page)
 {
 	struct deferred_split *ds_queue = get_deferred_split_queue(page);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a82104a..6009214 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -261,9 +261,6 @@ bool pm_suspended_storage(void)
 #ifdef CONFIG_HUGETLB_PAGE
 	free_huge_page,
 #endif
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	free_transhuge_page,
-#endif
 };
 
 int min_free_kbytes = 1024;
-- 
1.8.3.1