[PATCH 10/27] mm, vmscan: Clear congestion, dirty and need for compaction on a per-node basis

From: Mel Gorman
Date: Wed Apr 06 2016 - 07:28:21 EST


Congested and dirty tracking of a node and whether reclaim should stall
is still based on zone activity. This patch considers whether the kernel
should stall based on node-based reclaim activity.

Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
---
mm/vmscan.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index a631972d49e1..c62505f9e8be 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -3003,7 +3003,17 @@ static bool zone_balanced(struct zone *zone, int order,
{
unsigned long mark = high_wmark_pages(zone) + balance_gap;

- return zone_watermark_ok_safe(zone, order, mark, classzone_idx);
+ if (!zone_watermark_ok_safe(zone, order, mark, classzone_idx))
+ return false;
+
+ /*
+ * If any eligible zone is balanced then the node is not considered
+ * to be congested or dirty
+ */
+ clear_bit(PGDAT_CONGESTED, &zone->zone_pgdat->flags);
+ clear_bit(PGDAT_DIRTY, &zone->zone_pgdat->flags);
+
+ return true;
}

/*
@@ -3149,13 +3159,6 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int classzone_idx)
if (!zone_balanced(zone, order, 0, 0)) {
classzone_idx = i;
break;
- } else {
- /*
- * If any eligible zone is balanced then the
- * node is not considered congested or dirty.
- */
- clear_bit(PGDAT_CONGESTED, &zone->zone_pgdat->flags);
- clear_bit(PGDAT_DIRTY, &zone->zone_pgdat->flags);
}
}

@@ -3214,11 +3217,8 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int classzone_idx)
if (!populated_zone(zone))
continue;

- if (zone_balanced(zone, sc.order, 0, classzone_idx)) {
- clear_bit(PGDAT_CONGESTED, &pgdat->flags);
- clear_bit(PGDAT_DIRTY, &pgdat->flags);
+ if (zone_balanced(zone, sc.order, 0, classzone_idx))
goto out;
- }
}

/*
--
2.6.4