mm: remove zone_lru_lock() function, access ->lru_lock directly

We have common pattern to access lru_lock from a page pointer:
	zone_lru_lock(page_zone(page))

Which is silly, because it unfolds to this:
	&NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)]->zone_pgdat->lru_lock
while we can simply do
	&NODE_DATA(page_to_nid(page))->lru_lock

Remove zone_lru_lock() function, since it's only complicate things.  Use
'page_pgdat(page)->lru_lock' pattern instead.

[aryabinin@virtuozzo.com: a slightly better version of __split_huge_page()]
  Link: http://lkml.kernel.org/r/20190301121651.7741-1-aryabinin@virtuozzo.com
Link: http://lkml.kernel.org/r/20190228083329.31892-2-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 5 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index d4847026d4b1..fcf657886b4b 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2440,11 +2440,11 @@ static void __split_huge_page(struct page *page, struct list_head *list,
 		pgoff_t end, unsigned long flags)
 {
 	struct page *head = compound_head(page);
-	struct zone *zone = page_zone(head);
+	pg_data_t *pgdat = page_pgdat(head);
 	struct lruvec *lruvec;
 	int i;
 
-	lruvec = mem_cgroup_page_lruvec(head, zone->zone_pgdat);
+	lruvec = mem_cgroup_page_lruvec(head, pgdat);
 
 	/* complete memcg works before add pages to LRU */
 	mem_cgroup_split_huge_fixup(head);
@@ -2475,7 +2475,7 @@ static void __split_huge_page(struct page *page, struct list_head *list,
 		xa_unlock(&head->mapping->i_pages);
 	}
 
-	spin_unlock_irqrestore(zone_lru_lock(page_zone(head)), flags);
+	spin_unlock_irqrestore(&pgdat->lru_lock, flags);
 
 	remap_page(head);
 
@@ -2686,7 +2686,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 		lru_add_drain();
 
 	/* prevent PageLRU to go away from under us, and freeze lru stats */
-	spin_lock_irqsave(zone_lru_lock(page_zone(head)), flags);
+	spin_lock_irqsave(&pgdata->lru_lock, flags);
 
 	if (mapping) {
 		XA_STATE(xas, &mapping->i_pages, page_index(head));
@@ -2731,7 +2731,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 		spin_unlock(&pgdata->split_queue_lock);
 fail:		if (mapping)
 			xa_unlock(&mapping->i_pages);
-		spin_unlock_irqrestore(zone_lru_lock(page_zone(head)), flags);
+		spin_unlock_irqrestore(&pgdata->lru_lock, flags);
 		remap_page(head);
 		ret = -EBUSY;
 	}