[RFC v1 08/19] mm, vmscan: pass pgdat to wakeup_kswapd()

[Pengfei Li <fly@kernel.page>]

This is a preparation patch. Passing pgdat to wakeup_kswapd() and
avoiding indirect access to pgdat via zone->zone_pgdat.

Signed-off-by: Pengfei Li <fly@kernel.page>
---
 include/linux/mmzone.h |  2 +-
 mm/page_alloc.c        |  4 ++--
 mm/vmscan.c            | 12 ++++--------
 3 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index dd493239b8b2..599b30620aa1 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -814,7 +814,7 @@ static inline bool pgdat_is_empty(pg_data_t *pgdat)
 #include <linux/memory_hotplug.h>
 
 void build_all_zonelists(pg_data_t *pgdat);
-void wakeup_kswapd(struct zone *zone, gfp_t gfp_mask, int order,
+void wakeup_kswapd(pg_data_t *pgdat, gfp_t gfp_mask, int order,
 		   enum zone_type classzone_idx);
 bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
 			 int classzone_idx, unsigned int alloc_flags,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ec5f48b755ff..2dcf2a21c578 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3306,7 +3306,7 @@ struct page *rmqueue(struct zone *preferred_zone,
 	/* Separate test+clear to avoid unnecessary atomics */
 	if (test_bit(ZONE_BOOSTED_WATERMARK, &zone->flags)) {
 		clear_bit(ZONE_BOOSTED_WATERMARK, &zone->flags);
-		wakeup_kswapd(zone, 0, 0, zone_idx(zone));
+		wakeup_kswapd(zone->zone_pgdat, 0, 0, zone_idx(zone));
 	}
 
 	VM_BUG_ON_PAGE(page && bad_range(zone, page), page);
@@ -4173,7 +4173,7 @@ static void wake_all_kswapds(unsigned int order, gfp_t gfp_mask,
 	for_each_zone_nlist_nodemask(zone, &t, ac->nodelist, high_zoneidx,
 					ac->nodemask) {
 		if (last_pgdat != zone->zone_pgdat)
-			wakeup_kswapd(zone, gfp_mask, order, high_zoneidx);
+			wakeup_kswapd(zone->zone_pgdat, gfp_mask, order, high_zoneidx);
 		last_pgdat = zone->zone_pgdat;
 	}
 }
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 7554c8ba0841..b5256ef682c2 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -3964,17 +3964,13 @@ static int kswapd(void *p)
  * has failed or is not needed, still wake up kcompactd if only compaction is
  * needed.
  */
-void wakeup_kswapd(struct zone *zone, gfp_t gfp_flags, int order,
+void wakeup_kswapd(pg_data_t *pgdat, gfp_t gfp_flags, int order,
 		   enum zone_type classzone_idx)
 {
-	pg_data_t *pgdat;
-
-	if (!managed_zone(zone))
-		return;
+	int node = pgdat->node_id;
 
-	if (!cpuset_zone_allowed(zone, gfp_flags))
+	if (!cpuset_node_allowed(node, gfp_flags))
 		return;
-	pgdat = zone->zone_pgdat;
 
 	if (pgdat->kswapd_classzone_idx == MAX_NR_ZONES)
 		pgdat->kswapd_classzone_idx = classzone_idx;
@@ -4001,7 +3997,7 @@ void wakeup_kswapd(struct zone *zone, gfp_t gfp_flags, int order,
 		return;
 	}
 
-	trace_mm_vmscan_wakeup_kswapd(pgdat->node_id, classzone_idx, order,
+	trace_mm_vmscan_wakeup_kswapd(node, classzone_idx, order,
 				      gfp_flags);
 	wake_up_interruptible(&pgdat->kswapd_wait);
 }
-- 
2.23.0