mm: clean up zone flags

Page reclaim tests zone_is_reclaim_dirty(), but the site that actually
sets this state does zone_set_flag(zone, ZONE_TAIL_LRU_DIRTY), sending the
reader through layers indirection just to track down a simple bit.

Remove all zone flag wrappers and just use bitops against zone->flags
directly.  It's just as readable and the lines are barely any longer.

Also rename ZONE_TAIL_LRU_DIRTY to ZONE_DIRTY to match ZONE_WRITEBACK, and
remove the zone_flags_t typedef.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 14 insertions, 14 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index af72fe8..06123f2 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -920,7 +920,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 			/* Case 1 above */
 			if (current_is_kswapd() &&
 			    PageReclaim(page) &&
-			    zone_is_reclaim_writeback(zone)) {
+			    test_bit(ZONE_WRITEBACK, &zone->flags)) {
 				nr_immediate++;
 				goto keep_locked;
 
@@ -1002,7 +1002,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 			 */
 			if (page_is_file_cache(page) &&
 					(!current_is_kswapd() ||
-					 !zone_is_reclaim_dirty(zone))) {
+					 !test_bit(ZONE_DIRTY, &zone->flags))) {
 				/*
 				 * Immediately reclaim when written back.
 				 * Similar in principal to deactivate_page()
@@ -1563,7 +1563,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 	 * are encountered in the nr_immediate check below.
 	 */
 	if (nr_writeback && nr_writeback == nr_taken)
-		zone_set_flag(zone, ZONE_WRITEBACK);
+		set_bit(ZONE_WRITEBACK, &zone->flags);
 
 	/*
 	 * memcg will stall in page writeback so only consider forcibly
@@ -1575,16 +1575,16 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 		 * backed by a congested BDI and wait_iff_congested will stall.
 		 */
 		if (nr_dirty && nr_dirty == nr_congested)
-			zone_set_flag(zone, ZONE_CONGESTED);
+			set_bit(ZONE_CONGESTED, &zone->flags);
 
 		/*
 		 * If dirty pages are scanned that are not queued for IO, it
 		 * implies that flushers are not keeping up. In this case, flag
-		 * the zone ZONE_TAIL_LRU_DIRTY and kswapd will start writing
-		 * pages from reclaim context.
+		 * the zone ZONE_DIRTY and kswapd will start writing pages from
+		 * reclaim context.
 		 */
 		if (nr_unqueued_dirty == nr_taken)
-			zone_set_flag(zone, ZONE_TAIL_LRU_DIRTY);
+			set_bit(ZONE_DIRTY, &zone->flags);
 
 		/*
 		 * If kswapd scans pages marked marked for immediate
@@ -2984,7 +2984,7 @@ static bool kswapd_shrink_zone(struct zone *zone,
 	/* Account for the number of pages attempted to reclaim */
 	*nr_attempted += sc->nr_to_reclaim;
 
-	zone_clear_flag(zone, ZONE_WRITEBACK);
+	clear_bit(ZONE_WRITEBACK, &zone->flags);
 
 	/*
 	 * If a zone reaches its high watermark, consider it to be no longer
@@ -2994,8 +2994,8 @@ static bool kswapd_shrink_zone(struct zone *zone,
 	 */
 	if (zone_reclaimable(zone) &&
 	    zone_balanced(zone, testorder, 0, classzone_idx)) {
-		zone_clear_flag(zone, ZONE_CONGESTED);
-		zone_clear_flag(zone, ZONE_TAIL_LRU_DIRTY);
+		clear_bit(ZONE_CONGESTED, &zone->flags);
+		clear_bit(ZONE_DIRTY, &zone->flags);
 	}
 
 	return sc->nr_scanned >= sc->nr_to_reclaim;
@@ -3086,8 +3086,8 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order,
 				 * If balanced, clear the dirty and congested
 				 * flags
 				 */
-				zone_clear_flag(zone, ZONE_CONGESTED);
-				zone_clear_flag(zone, ZONE_TAIL_LRU_DIRTY);
+				clear_bit(ZONE_CONGESTED, &zone->flags);
+				clear_bit(ZONE_DIRTY, &zone->flags);
 			}
 		}
 
@@ -3714,11 +3714,11 @@ int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 	if (node_state(node_id, N_CPU) && node_id != numa_node_id())
 		return ZONE_RECLAIM_NOSCAN;
 
-	if (zone_test_and_set_flag(zone, ZONE_RECLAIM_LOCKED))
+	if (test_and_set_bit(ZONE_RECLAIM_LOCKED, &zone->flags))
 		return ZONE_RECLAIM_NOSCAN;
 
 	ret = __zone_reclaim(zone, gfp_mask, order);
-	zone_clear_flag(zone, ZONE_RECLAIM_LOCKED);
+	clear_bit(ZONE_RECLAIM_LOCKED, &zone->flags);
 
 	if (!ret)
 		count_vm_event(PGSCAN_ZONE_RECLAIM_FAILED);