From: Michal Hocko <mhocko@xxxxxxxx>
inactive_list_is_low is duplicating logic implemented by
lruvec_lru_size_eligibe_zones. Let's use the dedicated function to get
the number of eligible pages on the lru list and ask use lruvec_lru_size
to get the total LRU lize only when the tracing is really requested. We
are still iterating over all LRUs two times in that case but a)
inactive_list_is_low is not a hot path and b) this can be addressed at
the tracing layer and only evaluate arguments only when the tracing is
enabled in future if that ever matters.
Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>
---
mm/vmscan.c | 38 ++++++++++----------------------------
1 file changed, 10 insertions(+), 28 deletions(-)
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 137bc85067d3..a9c881f06c0e 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2054,11 +2054,10 @@ static bool inactive_list_is_low(struct lruvec *lruvec, bool file,
struct scan_control *sc, bool trace)
{
unsigned long inactive_ratio;
- unsigned long total_inactive, inactive;
- unsigned long total_active, active;
+ unsigned long inactive, active;
+ enum lru_list inactive_lru = file * LRU_FILE;
+ enum lru_list active_lru = file * LRU_FILE + LRU_ACTIVE;
unsigned long gb;
- struct pglist_data *pgdat = lruvec_pgdat(lruvec);
- int zid;
/*
* If we don't have swap space, anonymous page deactivation
@@ -2067,27 +2066,8 @@ static bool inactive_list_is_low(struct lruvec *lruvec, bool file,
if (!file && !total_swap_pages)
return false;
- total_inactive = inactive = lruvec_lru_size(lruvec, file * LRU_FILE);
- total_active = active = lruvec_lru_size(lruvec, file * LRU_FILE + LRU_ACTIVE);
-
- /*
- * For zone-constrained allocations, it is necessary to check if
- * deactivations are required for lowmem to be reclaimed. This
- * calculates the inactive/active pages available in eligible zones.
- */
- for (zid = sc->reclaim_idx + 1; zid < MAX_NR_ZONES; zid++) {
- struct zone *zone = &pgdat->node_zones[zid];
- unsigned long inactive_zone, active_zone;
-
- if (!managed_zone(zone))
- continue;
-
- inactive_zone = lruvec_zone_lru_size(lruvec, file * LRU_FILE, zid);
- active_zone = lruvec_zone_lru_size(lruvec, (file * LRU_FILE) + LRU_ACTIVE, zid);
-
- inactive -= min(inactive, inactive_zone);
- active -= min(active, active_zone);
- }
+ inactive = lruvec_lru_size_eligibe_zones(lruvec, inactive_lru, sc->reclaim_idx);
+ active = lruvec_lru_size_eligibe_zones(lruvec, active_lru, sc->reclaim_idx);
gb = (inactive + active) >> (30 - PAGE_SHIFT);
if (gb)
@@ -2096,10 +2076,12 @@ static bool inactive_list_is_low(struct lruvec *lruvec, bool file,
inactive_ratio = 1;
if (trace)
- trace_mm_vmscan_inactive_list_is_low(pgdat->node_id,
+ trace_mm_vmscan_inactive_list_is_low(lruvec_pgdat(lruvec)->node_id,
sc->reclaim_idx,
- total_inactive, inactive,
- total_active, active, inactive_ratio, file);
+ lruvec_lru_size(lruvec, inactive_lru), inactive,
+ lruvec_lru_size(lruvec, active_lru), active,
+ inactive_ratio, file);
+
return inactive * inactive_ratio < active;
}
--
2.11.0
--
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