[PATCH 14/16] mm: zone aging rounds accounting

[Wu Fengguang <wfg@mail.ustc.edu.cn>]

[-- Attachment #1: mm-account-zone-aging-rounds.patch --]
[-- Type: text/plain, Size: 2270 bytes --]

Add zone->aging_rounds to evaluate the balancing work.
It means how many rounds the zone has been fully scanned.

Signed-off-by: Wu Fengguang <wfg@mail.ustc.edu.cn>
---

 include/linux/mmzone.h |    1 +
 mm/page_alloc.c        |    5 +++++
 mm/vmscan.c            |    4 +++-
 3 files changed, 9 insertions(+), 1 deletion(-)

--- linux.orig/include/linux/mmzone.h
+++ linux/include/linux/mmzone.h
@@ -160,6 +160,7 @@ struct zone {
 	 */
 	unsigned long		aging_total;
 	unsigned long		aging_milestone;
+	unsigned long		aging_rounds;
 	unsigned long		page_age;
 
 	/*
--- linux.orig/mm/page_alloc.c
+++ linux/mm/page_alloc.c
@@ -1523,6 +1523,7 @@ void show_free_areas(void)
 			" inactive:%lukB"
 			" present:%lukB"
 			" aging:%lukB"
+			" aging_rounds:%lukB"
 			" age:%lu"
 			" pages_scanned:%lu"
 			" all_unreclaimable? %s"
@@ -1536,6 +1537,7 @@ void show_free_areas(void)
 			K(zone->nr_inactive),
 			K(zone->present_pages),
 			K(zone->aging_total),
+			zone->aging_rounds,
 			zone->page_age,
 			zone->pages_scanned,
 			(zone->all_unreclaimable ? "yes" : "no")
@@ -2149,6 +2151,7 @@ static void __init free_area_init_core(s
 		zone->nr_inactive = 0;
 		zone->aging_total = 0;
 		zone->aging_milestone = 0;
+		zone->aging_rounds = 0;
 		zone->page_age = 0;
 		atomic_set(&zone->reclaim_in_progress, 0);
 		if (!size)
@@ -2299,6 +2302,7 @@ static int zoneinfo_show(struct seq_file
 			   "\n        active   %lu"
 			   "\n        inactive %lu"
 			   "\n        aging    %lu"
+			   "\n        rounds   %lu"
 			   "\n        age      %lu"
 			   "\n        scanned  %lu (a: %lu)"
 			   "\n        spanned  %lu"
@@ -2310,6 +2314,7 @@ static int zoneinfo_show(struct seq_file
 			   zone->nr_active,
 			   zone->nr_inactive,
 			   zone->aging_total,
+			   zone->aging_rounds,
 			   zone->page_age,
 			   zone->pages_scanned,
 			   zone->nr_scan_active / 1024,
--- linux.orig/mm/vmscan.c
+++ linux/mm/vmscan.c
@@ -157,8 +157,10 @@ static inline void update_zone_age(struc
 
 	z->aging_total += nr_scan;
 
-	if (z->aging_total - z->aging_milestone > len)
+	if (z->aging_total - z->aging_milestone > len) {
 		z->aging_milestone += len;
+		z->aging_rounds++;
+	}
 
 	z->page_age = ((z->aging_total - z->aging_milestone)
 						<< PAGE_AGE_SHIFT) / len;

--