[PATCH v6 01/15] mm/mglru: report evictable sizes per type

["Barry Song (Xiaomi)" <baohua@kernel.org>]

From: Kairui Song <kasong@tencent.com>

Change lruvec_evictable_size() to return the number of evictable
anonymous and file pages separately instead of a single total, so
that callers can weigh the two types independently.

Update lruvec_is_sizable() and get_nr_to_scan() accordingly; the
summed totals are unchanged, so there is no functional change.

Signed-off-by: Kairui Song <kasong@tencent.com>
Signed-off-by: Barry Song (Xiaomi) <baohua@kernel.org>
Reviewed-by: Kunwu Chan <kunwu.chan@gmail.com>
---
 mm/vmscan.c | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 061fbd168d98..acc4efccda2f 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -4192,28 +4192,31 @@ static void set_initial_priority(struct pglist_data *pgdat, struct scan_control
 	sc->priority = clamp(priority, DEF_PRIORITY / 2, DEF_PRIORITY);
 }
 
-static unsigned long lruvec_evictable_size(struct lruvec *lruvec, int swappiness)
+static void lruvec_evictable_size(struct lruvec *lruvec, int swappiness,
+				  unsigned long nr[])
 {
 	int type;
-	unsigned long seq, total = 0;
+	unsigned long seq;
 	struct lru_gen_folio *lrugen = &lruvec->lrugen;
 	DEFINE_MAX_SEQ(lruvec);
 	DEFINE_MIN_SEQ(lruvec);
 
+	nr[LRU_GEN_ANON] = 0;
+	nr[LRU_GEN_FILE] = 0;
+
 	for_each_evictable_type(type, swappiness) {
 		for (seq = min_seq[type]; seq <= max_seq; seq++)
-			total += lruvec_gen_size(lrugen, type, seq);
+			nr[type] += lruvec_gen_size(lrugen, type, seq);
 	}
-
-	return total;
 }
 
 static bool lruvec_is_sizable(struct lruvec *lruvec, struct scan_control *sc)
 {
-	unsigned long total;
+	unsigned long total, sizes[ANON_AND_FILE];
 	int swappiness = get_swappiness(lruvec, sc);
 
-	total = lruvec_evictable_size(lruvec, swappiness);
+	lruvec_evictable_size(lruvec, swappiness, sizes);
+	total = sizes[LRU_GEN_ANON] + sizes[LRU_GEN_FILE];
 
 	/* whether the size is big enough to be helpful */
 	return total >> sc->priority;
@@ -5021,7 +5024,7 @@ static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq,
 static long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc,
 			   struct mem_cgroup *memcg, int swappiness)
 {
-	unsigned long nr_to_scan, evictable;
+	unsigned long nr_to_scan, evictable, sizes[ANON_AND_FILE];
 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
 
 	/*
@@ -5037,7 +5040,8 @@ static long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc,
 			return 0;
 	}
 
-	evictable = lruvec_evictable_size(lruvec, swappiness);
+	lruvec_evictable_size(lruvec, swappiness, sizes);
+	evictable = sizes[LRU_GEN_ANON] + sizes[LRU_GEN_FILE];
 
 	nr_to_scan = apply_proportional_protection(memcg, sc, evictable);
 	nr_to_scan >>= sc->priority;
-- 
2.34.1