[PATCH 13/16] mm/huge_memory: add helper __get_deferred_split_queue

[Miaohe Lin]

Add helper __get_deferred_split_queue to remove the duplicated codes of
getting ds_queue. No functional change intended.

Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
 mm/huge_memory.c | 35 ++++++++++++-----------------------
 1 file changed, 12 insertions(+), 23 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 0030b4f67cd9..de8155ff584c 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -555,25 +555,23 @@ pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma)
 	return pmd;
 }
 
-#ifdef CONFIG_MEMCG
-static inline struct deferred_split *get_deferred_split_queue(struct page *page)
+static inline struct deferred_split *__get_deferred_split_queue(struct pglist_data *pgdat,
+								struct mem_cgroup *memcg)
 {
-	struct mem_cgroup *memcg = page_memcg(compound_head(page));
-	struct pglist_data *pgdat = NODE_DATA(page_to_nid(page));
-
+#ifdef CONFIG_MEMCG
 	if (memcg)
 		return &memcg->deferred_split_queue;
-	else
-		return &pgdat->deferred_split_queue;
+#endif
+	return &pgdat->deferred_split_queue;
 }
-#else
+
 static inline struct deferred_split *get_deferred_split_queue(struct page *page)
 {
+	struct mem_cgroup *memcg = page_memcg(compound_head(page));
 	struct pglist_data *pgdat = NODE_DATA(page_to_nid(page));
 
-	return &pgdat->deferred_split_queue;
+	return __get_deferred_split_queue(pgdat, memcg);
 }
-#endif
 
 void prep_transhuge_page(struct page *page)
 {
@@ -2774,31 +2772,22 @@ void deferred_split_huge_page(struct page *page)
 static unsigned long deferred_split_count(struct shrinker *shrink,
 		struct shrink_control *sc)
 {
-	struct pglist_data *pgdata = NODE_DATA(sc->nid);
-	struct deferred_split *ds_queue = &pgdata->deferred_split_queue;
+	struct deferred_split *ds_queue;
 
-#ifdef CONFIG_MEMCG
-	if (sc->memcg)
-		ds_queue = &sc->memcg->deferred_split_queue;
-#endif
+	ds_queue = __get_deferred_split_queue(NODE_DATA(sc->nid), sc->memcg);
 	return READ_ONCE(ds_queue->split_queue_len);
 }
 
 static unsigned long deferred_split_scan(struct shrinker *shrink,
 		struct shrink_control *sc)
 {
-	struct pglist_data *pgdata = NODE_DATA(sc->nid);
-	struct deferred_split *ds_queue = &pgdata->deferred_split_queue;
+	struct deferred_split *ds_queue;
 	unsigned long flags;
 	LIST_HEAD(list), *pos, *next;
 	struct page *page;
 	int split = 0;
 
-#ifdef CONFIG_MEMCG
-	if (sc->memcg)
-		ds_queue = &sc->memcg->deferred_split_queue;
-#endif
-
+	ds_queue = __get_deferred_split_queue(NODE_DATA(sc->nid), sc->memcg);
 	spin_lock_irqsave(&ds_queue->split_queue_lock, flags);
 	/* Take pin on all head pages to avoid freeing them under us */
 	list_for_each_safe(pos, next, &ds_queue->split_queue) {
-- 
2.23.0