[PATCH 10/25] mm, vmscan: Make shrink_node decisions more node-centric
From: Mel Gorman
Date: Mon Jun 08 2015 - 09:57:25 EST
Earlier patches focused on having direct reclaim and kswapd use data that
is node-centric for reclaiming but shrink_node() itself still uses too much
zone information. This patch removes unnecessary zone-based information
with the most important decision being whether to continue reclaim or
not. Some memcg APIs are adjusted as a result even though memcg itself
still uses some zone information.
Signed-off-by: Mel Gorman <mgorman@xxxxxxx>
---
include/linux/memcontrol.h | 9 ++++----
include/linux/mmzone.h | 4 ++--
include/linux/swap.h | 2 +-
mm/memcontrol.c | 17 ++++++++-------
mm/page_alloc.c | 2 +-
mm/vmscan.c | 53 ++++++++++++++++++++++++++--------------------
6 files changed, 48 insertions(+), 39 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index df225059daf3..b1ba7f5b3851 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -84,7 +84,8 @@ void mem_cgroup_uncharge_list(struct list_head *page_list);
void mem_cgroup_migrate(struct page *oldpage, struct page *newpage,
bool lrucare);
-struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
+struct lruvec *mem_cgroup_lruvec(struct pglist_data *, struct zone *zone,
+ struct mem_cgroup *);
struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *);
bool mem_cgroup_is_descendant(struct mem_cgroup *memcg,
@@ -240,10 +241,10 @@ static inline void mem_cgroup_migrate(struct page *oldpage,
{
}
-static inline struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone,
- struct mem_cgroup *memcg)
+static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
+ struct zone *zone, struct mem_cgroup *memcg)
{
- return zone_lruvec(zone);
+ return node_lruvec(pgdat);
}
static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index fab74af19f26..1830c2180555 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -799,9 +799,9 @@ static inline spinlock_t *zone_lru_lock(struct zone *zone)
return &zone->zone_pgdat->lru_lock;
}
-static inline struct lruvec *zone_lruvec(struct zone *zone)
+static inline struct lruvec *node_lruvec(struct pglist_data *pgdat)
{
- return &zone->zone_pgdat->lruvec;
+ return &pgdat->lruvec;
}
static inline unsigned long pgdat_end_pfn(pg_data_t *pgdat)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 7067eca501e2..bb9597213e39 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -323,7 +323,7 @@ extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
unsigned long nr_pages,
gfp_t gfp_mask,
bool may_swap);
-extern unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
+extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem,
gfp_t gfp_mask, bool noswap,
struct zone *zone,
unsigned long *nr_scanned);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 10eed58506a0..7c39930c8d86 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1170,22 +1170,23 @@ out:
EXPORT_SYMBOL(__mem_cgroup_count_vm_event);
/**
- * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg
+ * mem_cgroup_lruvec - get the lru list vector for a node or a memcg zone
+ * @node: node of the wanted lruvec
* @zone: zone of the wanted lruvec
* @memcg: memcg of the wanted lruvec
*
- * Returns the lru list vector holding pages for the given @zone and
- * @mem. This can be the global zone lruvec, if the memory controller
+ * Returns the lru list vector holding pages for a given @node or a given
+ * @memcg and @zone. This can be the node lruvec, if the memory controller
* is disabled.
*/
-struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone,
- struct mem_cgroup *memcg)
+struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
+ struct zone *zone, struct mem_cgroup *memcg)
{
struct mem_cgroup_per_zone *mz;
struct lruvec *lruvec;
if (mem_cgroup_disabled()) {
- lruvec = zone_lruvec(zone);
+ lruvec = node_lruvec(pgdat);
goto out;
}
@@ -1721,8 +1722,8 @@ static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg,
}
continue;
}
- total += mem_cgroup_shrink_node_zone(victim, gfp_mask, false,
- zone, &nr_scanned);
+ total += mem_cgroup_shrink_node(victim, gfp_mask, false,
+ zone, &nr_scanned);
*total_scanned += nr_scanned;
if (!soft_limit_excess(root_memcg))
break;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 49a29e8ae493..34201c141916 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4879,6 +4879,7 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
init_waitqueue_head(&pgdat->kswapd_wait);
init_waitqueue_head(&pgdat->pfmemalloc_wait);
pgdat_page_ext_init(pgdat);
+ lruvec_init(node_lruvec(pgdat));
for (j = 0; j < MAX_NR_ZONES; j++) {
struct zone *zone = pgdat->node_zones + j;
@@ -4948,7 +4949,6 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
/* For bootup, initialized properly in watermark setup */
mod_zone_page_state(zone, NR_ALLOC_BATCH, zone->managed_pages);
- lruvec_init(zone_lruvec(zone));
if (!size)
continue;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index e069decbcfa1..3a6a2fac48e5 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2278,13 +2278,14 @@ static bool in_reclaim_compaction(struct scan_control *sc)
* calls try_to_compact_zone() that it will have enough free pages to succeed.
* It will give up earlier than that if there is difficulty reclaiming pages.
*/
-static inline bool should_continue_reclaim(struct zone *zone,
+static inline bool should_continue_reclaim(struct pglist_data *pgdat,
unsigned long nr_reclaimed,
unsigned long nr_scanned,
struct scan_control *sc)
{
unsigned long pages_for_compaction;
unsigned long inactive_lru_pages;
+ int z;
/* If not in reclaim/compaction mode, stop */
if (!in_reclaim_compaction(sc))
@@ -2318,21 +2319,27 @@ static inline bool should_continue_reclaim(struct zone *zone,
* inactive lists are large enough, continue reclaiming
*/
pages_for_compaction = (2UL << sc->order);
- inactive_lru_pages = node_page_state(zone->zone_pgdat, NR_INACTIVE_FILE);
+ inactive_lru_pages = node_page_state(pgdat, NR_INACTIVE_FILE);
if (get_nr_swap_pages() > 0)
- inactive_lru_pages += node_page_state(zone->zone_pgdat, NR_INACTIVE_ANON);
+ inactive_lru_pages += node_page_state(pgdat, NR_INACTIVE_ANON);
if (sc->nr_reclaimed < pages_for_compaction &&
inactive_lru_pages > pages_for_compaction)
return true;
/* If compaction would go ahead or the allocation would succeed, stop */
- switch (compaction_suitable(zone, sc->order, 0, 0)) {
- case COMPACT_PARTIAL:
- case COMPACT_CONTINUE:
- return false;
- default:
- return true;
+ for (z = 0; z <= sc->reclaim_idx; z++) {
+ struct zone *zone = &pgdat->node_zones[z];
+
+ switch (compaction_suitable(zone, sc->order, 0, 0)) {
+ case COMPACT_PARTIAL:
+ case COMPACT_CONTINUE:
+ return false;
+ default:
+ /* check next zone */
+ ;
+ }
}
+ return true;
}
static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc,
@@ -2342,15 +2349,14 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc,
struct reclaim_state *reclaim_state = current->reclaim_state;
unsigned long nr_reclaimed, nr_scanned;
bool reclaimable = false;
- struct zone *zone = &pgdat->node_zones[classzone_idx];
do {
struct mem_cgroup *root = sc->target_mem_cgroup;
struct mem_cgroup_reclaim_cookie reclaim = {
- .zone = zone,
+ .zone = &pgdat->node_zones[classzone_idx],
.priority = sc->priority,
};
- unsigned long zone_lru_pages = 0;
+ unsigned long node_lru_pages = 0;
struct mem_cgroup *memcg;
nr_reclaimed = sc->nr_reclaimed;
@@ -2369,23 +2375,24 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc,
mem_cgroup_events(memcg, MEMCG_LOW, 1);
}
- lruvec = mem_cgroup_zone_lruvec(zone, memcg);
+ lruvec = mem_cgroup_lruvec(pgdat,
+ &pgdat->node_zones[reclaim_idx], memcg);
swappiness = mem_cgroup_swappiness(memcg);
scanned = sc->nr_scanned;
sc->reclaim_idx = reclaim_idx;
shrink_lruvec(lruvec, swappiness, sc, &lru_pages);
- zone_lru_pages += lru_pages;
+ node_lru_pages += lru_pages;
if (!global_reclaim(sc) && reclaim_idx == classzone_idx)
- shrink_slab(sc->gfp_mask, zone_to_nid(zone),
+ shrink_slab(sc->gfp_mask, pgdat->node_id,
memcg, sc->nr_scanned - scanned,
lru_pages);
/*
* Direct reclaim and kswapd have to scan all memory
* cgroups to fulfill the overall scan target for the
- * zone.
+ * node.
*
* Limit reclaim, on the other hand, only cares about
* nr_to_reclaim pages to be reclaimed and it will
@@ -2404,9 +2411,9 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc,
* the eligible LRU pages were scanned.
*/
if (global_reclaim(sc) && reclaim_idx == classzone_idx)
- shrink_slab(sc->gfp_mask, zone_to_nid(zone), NULL,
+ shrink_slab(sc->gfp_mask, pgdat->node_id, NULL,
sc->nr_scanned - nr_scanned,
- zone_lru_pages);
+ node_lru_pages);
if (reclaim_state) {
sc->nr_reclaimed += reclaim_state->reclaimed_slab;
@@ -2420,7 +2427,7 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc,
if (sc->nr_reclaimed - nr_reclaimed)
reclaimable = true;
- } while (should_continue_reclaim(zone, sc->nr_reclaimed - nr_reclaimed,
+ } while (should_continue_reclaim(pgdat, sc->nr_reclaimed - nr_reclaimed,
sc->nr_scanned - nr_scanned, sc));
return reclaimable;
@@ -2822,7 +2829,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
#ifdef CONFIG_MEMCG
-unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *memcg,
+unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg,
gfp_t gfp_mask, bool noswap,
struct zone *zone,
unsigned long *nr_scanned)
@@ -2834,7 +2841,7 @@ unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *memcg,
.may_unmap = 1,
.may_swap = !noswap,
};
- struct lruvec *lruvec = mem_cgroup_zone_lruvec(zone, memcg);
+ struct lruvec *lruvec = mem_cgroup_lruvec(zone->zone_pgdat, zone, memcg);
int swappiness = mem_cgroup_swappiness(memcg);
unsigned long lru_pages;
@@ -2848,7 +2855,7 @@ unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *memcg,
/*
* NOTE: Although we can get the priority field, using it
* here is not a good idea, since it limits the pages we can scan.
- * if we don't reclaim here, the shrink_zone from balance_pgdat
+ * if we don't reclaim here, the shrink_node from balance_pgdat
* will pick up pages from other mem cgroup's as well. We hack
* the priority and make it zero.
*/
@@ -2910,7 +2917,7 @@ static void age_active_anon(struct pglist_data *pgdat,
memcg = mem_cgroup_iter(NULL, NULL, NULL);
do {
- struct lruvec *lruvec = mem_cgroup_zone_lruvec(zone, memcg);
+ struct lruvec *lruvec = mem_cgroup_lruvec(pgdat, zone, memcg);
if (inactive_anon_is_low(lruvec))
shrink_active_list(SWAP_CLUSTER_MAX, lruvec,
--
2.3.5
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