[02/14] mm: keep separate anon and file statistics on page reclaim activity

Commit Message

Johannes Weiner May 20, 2020, 11:25 p.m. UTC

Having statistics on pages scanned and pages reclaimed for both anon
and file pages makes it easier to evaluate changes to LRU balancing.

While at it, clean up the stat-keeping mess for isolation, putback,
reclaim stats etc. a bit: first the physical LRU operation (isolation
and putback), followed by vmstats, reclaim_stats, and then vm events.

Signed-off-by: Johannes Weiner <[e-mail]>
---
 include/linux/vm_event_item.h |  4 ++++
 mm/vmscan.c                   | 17 +++++++++--------
 mm/vmstat.c                   |  4 ++++
 3 files changed, 17 insertions(+), 8 deletions(-)

Patch

diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
index ffef0f279747..24fc7c3ae7d6 100644
--- a/include/linux/vm_event_item.h
+++ b/include/linux/vm_event_item.h
@@ -35,6 +35,10 @@  enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
 		PGSCAN_KSWAPD,
 		PGSCAN_DIRECT,
 		PGSCAN_DIRECT_THROTTLE,
+		PGSCAN_ANON,
+		PGSCAN_FILE,
+		PGSTEAL_ANON,
+		PGSTEAL_FILE,
 #ifdef CONFIG_NUMA
 		PGSCAN_ZONE_RECLAIM_FAILED,
 #endif
diff --git a/mm/vmscan.c b/mm/vmscan.c
index cc555903a332..70b0e2c6a4b9 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1913,7 +1913,7 @@  shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 	unsigned int nr_reclaimed = 0;
 	unsigned long nr_taken;
 	struct reclaim_stat stat;
-	int file = is_file_lru(lru);
+	bool file = is_file_lru(lru);
 	enum vm_event_item item;
 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
 	struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat;
@@ -1941,11 +1941,12 @@  shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 
 	__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, nr_taken);
 	reclaim_stat->recent_scanned[file] += nr_taken;
-
 	item = current_is_kswapd() ? PGSCAN_KSWAPD : PGSCAN_DIRECT;
 	if (!cgroup_reclaim(sc))
 		__count_vm_events(item, nr_scanned);
 	__count_memcg_events(lruvec_memcg(lruvec), item, nr_scanned);
+	__count_vm_events(PGSCAN_ANON + file, nr_scanned);
+
 	spin_unlock_irq(&pgdat->lru_lock);
 
 	if (nr_taken == 0)
@@ -1956,16 +1957,16 @@  shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 
 	spin_lock_irq(&pgdat->lru_lock);
 
+	move_pages_to_lru(lruvec, &page_list);
+
+	__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);
+	reclaim_stat->recent_rotated[0] += stat.nr_activate[0];
+	reclaim_stat->recent_rotated[1] += stat.nr_activate[1];
 	item = current_is_kswapd() ? PGSTEAL_KSWAPD : PGSTEAL_DIRECT;
 	if (!cgroup_reclaim(sc))
 		__count_vm_events(item, nr_reclaimed);
 	__count_memcg_events(lruvec_memcg(lruvec), item, nr_reclaimed);
-	reclaim_stat->recent_rotated[0] += stat.nr_activate[0];
-	reclaim_stat->recent_rotated[1] += stat.nr_activate[1];
-
-	move_pages_to_lru(lruvec, &page_list);
-
-	__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);
+	__count_vm_events(PGSTEAL_ANON + file, nr_reclaimed);
 
 	spin_unlock_irq(&pgdat->lru_lock);
 
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 4b0c90e4de71..3d06bd89d9ec 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1201,6 +1201,10 @@  const char * const vmstat_text[] = {
 	"pgscan_kswapd",
 	"pgscan_direct",
 	"pgscan_direct_throttle",
+	"pgscan_anon",
+	"pgscan_file",
+	"pgsteal_anon",
+	"pgsteal_file",
 
 #ifdef CONFIG_NUMA
 	"zone_reclaim_failed",