[PATCH] mm: Show watermark_boost of zone in zoneinfo

[Liangcai Fan]

min/low/high_wmark_pages(z) is defined as
(z->_watermark[WMARK_MIN/LOW/HIGH] + z->watermark_boost).
If kswapd is frequently waked up due to the increase of
min/low/high_wmark_pages, printing watermark_boost can quickly locate
whether watermark_boost or _watermark[WMARK_MIN/LOW/HIGH] caused
min/low/high_wmark_pages to increase.

Signed-off-by: Liangcai Fan <liangcaifan19@xxxxxxxxx>
---
 mm/page_alloc.c | 2 ++
 mm/vmstat.c     | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index b37435c..fe343ad 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5980,6 +5980,7 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
 		printk(KERN_CONT
 			"%s"
 			" free:%lukB"
+			" boost:%lukB"
 			" min:%lukB"
 			" low:%lukB"
 			" high:%lukB"
@@ -6000,6 +6001,7 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
 			"\n",
 			zone->name,
 			K(zone_page_state(zone, NR_FREE_PAGES)),
+			K(zone->watermark_boost),
 			K(min_wmark_pages(zone)),
 			K(low_wmark_pages(zone)),
 			K(high_wmark_pages(zone)),
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 8ce2620..dbe37ed 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1656,6 +1656,7 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
 	}
 	seq_printf(m,
 		   "\n  pages free     %lu"
+		   "\n        boost    %lu"
 		   "\n        min      %lu"
 		   "\n        low      %lu"
 		   "\n        high     %lu"
@@ -1664,6 +1665,7 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
 		   "\n        managed  %lu"
 		   "\n        cma      %lu",
 		   zone_page_state(zone, NR_FREE_PAGES),
+		   zone->watermark_boost,
 		   min_wmark_pages(zone),
 		   low_wmark_pages(zone),
 		   high_wmark_pages(zone),
-- 
1.9.1