mm/vmscan: remove unused lru_pages argument

Since 9092c71 ("mm: use sc->priority for slab shrink targets") the
argument 'unsigned long *lru_pages' passed around with no purpose.  Remove
it.

Link: http://lkml.kernel.org/r/20190228083329.31892-4-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
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>

mm/vmscan.c

@@ -2302,8 +2302,7 @@ enum scan_balance {
  * nr[2] = file inactive pages to scan; nr[3] = file active pages to scan
  */
 static void get_scan_count(struct lruvec *lruvec, struct mem_cgroup *memcg,
-			   struct scan_control *sc, unsigned long *nr,
-			   unsigned long *lru_pages)
+			   struct scan_control *sc, unsigned long *nr)
 {
 	int swappiness = mem_cgroup_swappiness(memcg);
 	struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat;
@@ -2454,7 +2453,6 @@ static void get_scan_count(struct lruvec *lruvec, struct mem_cgroup *memcg,
 	fraction[1] = fp;
 	denominator = ap + fp + 1;
 out:
-	*lru_pages = 0;
 	for_each_evictable_lru(lru) {
 		int file = is_file_lru(lru);
 		unsigned long lruvec_size;
@@ -2549,7 +2547,6 @@ static void get_scan_count(struct lruvec *lruvec, struct mem_cgroup *memcg,
 			BUG();
 		}
 
-		*lru_pages += lruvec_size;
 		nr[lru] = scan;
 	}
 }
@@ -2558,7 +2555,7 @@ static void get_scan_count(struct lruvec *lruvec, struct mem_cgroup *memcg,
  * This is a basic per-node page freer.  Used by both kswapd and direct reclaim.
  */
 static void shrink_node_memcg(struct pglist_data *pgdat, struct mem_cgroup *memcg,
-			      struct scan_control *sc, unsigned long *lru_pages)
+			      struct scan_control *sc)
 {
 	struct lruvec *lruvec = mem_cgroup_lruvec(pgdat, memcg);
 	unsigned long nr[NR_LRU_LISTS];
@@ -2570,7 +2567,7 @@ static void shrink_node_memcg(struct pglist_data *pgdat, struct mem_cgroup *memc
 	struct blk_plug plug;
 	bool scan_adjusted;
 
-	get_scan_count(lruvec, memcg, sc, nr, lru_pages);
+	get_scan_count(lruvec, memcg, sc, nr);
 
 	/* Record the original scan target for proportional adjustments later */
 	memcpy(targets, nr, sizeof(nr));
@@ -2758,7 +2755,6 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
 
 	do {
 		struct mem_cgroup *root = sc->target_mem_cgroup;
-		unsigned long node_lru_pages = 0;
 		struct mem_cgroup *memcg;
 
 		memset(&sc->nr, 0, sizeof(sc->nr));
@@ -2768,7 +2764,6 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
 
 		memcg = mem_cgroup_iter(root, NULL, NULL);
 		do {
-			unsigned long lru_pages;
 			unsigned long reclaimed;
 			unsigned long scanned;
 
@@ -2805,8 +2800,7 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
 
 			reclaimed = sc->nr_reclaimed;
 			scanned = sc->nr_scanned;
-			shrink_node_memcg(pgdat, memcg, sc, &lru_pages);
-			node_lru_pages += lru_pages;
+			shrink_node_memcg(pgdat, memcg, sc);
 
 			shrink_slab(sc->gfp_mask, pgdat->node_id, memcg,
 					sc->priority);
@@ -3317,7 +3311,6 @@ unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg,
 		.reclaim_idx = MAX_NR_ZONES - 1,
 		.may_swap = !noswap,
 	};
-	unsigned long lru_pages;
 
 	WARN_ON_ONCE(!current->reclaim_state);
 
@@ -3334,7 +3327,7 @@ unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg,
 	 * will pick up pages from other mem cgroup's as well. We hack
 	 * the priority and make it zero.
 	 */
-	shrink_node_memcg(pgdat, memcg, &sc, &lru_pages);
+	shrink_node_memcg(pgdat, memcg, &sc);
 
 	trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed);