From: Keith Busch <keith.busch@xxxxxxxxx>
Age and reclaim anonymous pages if a migration path is available. The
node has other recourses for inactive anonymous pages beyond swap,
Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx>
Co-developed-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
---
b/include/linux/swap.h | 20 ++++++++++++++++++++
b/mm/vmscan.c | 10 +++++-----
2 files changed, 25 insertions(+), 5 deletions(-)
diff -puN include/linux/swap.h~0006-mm-vmscan-Consider-anonymous-pages-without-swap include/linux/swap.h
--- a/include/linux/swap.h~0006-mm-vmscan-Consider-anonymous-pages-without-swap 2019-10-16 15:06:59.474952590 -0700
+++ b/include/linux/swap.h 2019-10-16 15:06:59.481952590 -0700
@@ -680,5 +680,25 @@ static inline bool mem_cgroup_swap_full(
}
#endif
+static inline bool reclaim_anon_pages(struct mem_cgroup *memcg,
+ int node_id)
+{
+ /* Always age anon pages when we have swap */
+ if (memcg == NULL) {
+ if (get_nr_swap_pages() > 0)
+ return true;
+ } else {
+ if (mem_cgroup_get_nr_swap_pages(memcg) > 0)
+ return true;
+ }
+
+ /* Also age anon pages if we can auto-migrate them */
+ if (next_migration_node(node_id) >= 0)
+ return true;
+
+ /* No way to reclaim anon pages */
+ return false;
+}
+
#endif /* __KERNEL__*/
#endif /* _LINUX_SWAP_H */
diff -puN mm/vmscan.c~0006-mm-vmscan-Consider-anonymous-pages-without-swap mm/vmscan.c
--- a/mm/vmscan.c~0006-mm-vmscan-Consider-anonymous-pages-without-swap 2019-10-16 15:06:59.477952590 -0700
+++ b/mm/vmscan.c 2019-10-16 15:06:59.482952590 -0700
@@ -327,7 +327,7 @@ unsigned long zone_reclaimable_pages(str
nr = zone_page_state_snapshot(zone, NR_ZONE_INACTIVE_FILE) +
zone_page_state_snapshot(zone, NR_ZONE_ACTIVE_FILE);
- if (get_nr_swap_pages() > 0)
+ if (reclaim_anon_pages(NULL, zone_to_nid(zone)))
nr += zone_page_state_snapshot(zone, NR_ZONE_INACTIVE_ANON) +
zone_page_state_snapshot(zone, NR_ZONE_ACTIVE_ANON);
@@ -2166,7 +2166,7 @@ static bool inactive_list_is_low(struct
* If we don't have swap space, anonymous page deactivation
* is pointless.
*/
- if (!file && !total_swap_pages)
+ if (!file && !reclaim_anon_pages(NULL, pgdat->node_id))
return false;
inactive = lruvec_lru_size(lruvec, inactive_lru, sc->reclaim_idx);
@@ -2241,7 +2241,7 @@ static void get_scan_count(struct lruvec
enum lru_list lru;
/* If we have no swap space, do not bother scanning anon pages. */
- if (!sc->may_swap || mem_cgroup_get_nr_swap_pages(memcg) <= 0) {
+ if (!sc->may_swap || !reclaim_anon_pages(memcg, pgdat->node_id)) {
scan_balance = SCAN_FILE;
goto out;
}
@@ -2604,7 +2604,7 @@ static inline bool should_continue_recla
*/
pages_for_compaction = compact_gap(sc->order);
inactive_lru_pages = node_page_state(pgdat, NR_INACTIVE_FILE);
- if (get_nr_swap_pages() > 0)
+ if (!reclaim_anon_pages(NULL, pgdat->node_id))
inactive_lru_pages += node_page_state(pgdat, NR_INACTIVE_ANON);
if (sc->nr_reclaimed < pages_for_compaction &&
inactive_lru_pages > pages_for_compaction)
@@ -3289,7 +3289,7 @@ static void age_active_anon(struct pglis
{
struct mem_cgroup *memcg;
- if (!total_swap_pages)
+ if (!reclaim_anon_pages(NULL, pgdat->node_id))
return;
memcg = mem_cgroup_iter(NULL, NULL, NULL);
_
