[PATCH 12/31] mm, vmscan: make shrink_node decisions more node-centric
From: Mel Gorman
Date: Fri Jul 01 2016 - 16:04:00 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@xxxxxxxxxxxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
---
include/linux/memcontrol.h | 19 ++++++++--------
include/linux/mmzone.h | 4 ++--
include/linux/swap.h | 2 +-
mm/memcontrol.c | 4 ++--
mm/page_alloc.c | 2 +-
mm/vmscan.c | 57 ++++++++++++++++++++++++++--------------------
mm/workingset.c | 6 ++---
7 files changed, 51 insertions(+), 43 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 1927dcb6921e..48b43c709ed7 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -325,22 +325,23 @@ mem_cgroup_zone_zoneinfo(struct mem_cgroup *memcg, struct zone *zone)
}
/**
- * 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.
*/
-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)
{
struct mem_cgroup_per_zone *mz;
struct lruvec *lruvec;
if (mem_cgroup_disabled()) {
- lruvec = zone_lruvec(zone);
+ lruvec = node_lruvec(pgdat);
goto out;
}
@@ -610,10 +611,10 @@ static inline void mem_cgroup_migrate(struct page *old, struct page *new)
{
}
-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 eb74e63df5cf..f88cbbb476c8 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -739,9 +739,9 @@ 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 916e2eddecd6..0ad616d7c381 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -316,7 +316,7 @@ 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 50c86ad121bc..c9ebec98e92a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1432,8 +1432,8 @@ 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 f58548139bf2..b76ea2527c09 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5954,6 +5954,7 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat)
#endif
pgdat_page_ext_init(pgdat);
spin_lock_init(&pgdat->lru_lock);
+ lruvec_init(node_lruvec(pgdat));
for (j = 0; j < MAX_NR_ZONES; j++) {
struct zone *zone = pgdat->node_zones + j;
@@ -6016,7 +6017,6 @@ 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 2f898ba2ee2e..b8e0f76b6e00 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2226,10 +2226,11 @@ static inline void init_tlb_ubc(void)
/*
* This is a basic per-zone page freer. Used by both kswapd and direct reclaim.
*/
-static void shrink_zone_memcg(struct zone *zone, struct mem_cgroup *memcg,
+static void shrink_node_memcg(struct pglist_data *pgdat, struct mem_cgroup *memcg,
struct scan_control *sc, unsigned long *lru_pages)
{
- struct lruvec *lruvec = mem_cgroup_zone_lruvec(zone, memcg);
+ struct zone *zone = &pgdat->node_zones[sc->reclaim_idx];
+ struct lruvec *lruvec = mem_cgroup_lruvec(pgdat, zone, memcg);
unsigned long nr[NR_LRU_LISTS];
unsigned long targets[NR_LRU_LISTS];
unsigned long nr_to_scan;
@@ -2362,13 +2363,14 @@ 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))
@@ -2402,21 +2404,27 @@ 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, sc->reclaim_idx)) {
+ 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,
@@ -2425,15 +2433,14 @@ 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;
@@ -2454,11 +2461,11 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc,
reclaimed = sc->nr_reclaimed;
scanned = sc->nr_scanned;
- shrink_zone_memcg(zone, memcg, sc, &lru_pages);
- zone_lru_pages += lru_pages;
+ shrink_node_memcg(pgdat, memcg, sc, &lru_pages);
+ node_lru_pages += lru_pages;
if (!global_reclaim(sc))
- shrink_slab(sc->gfp_mask, zone_to_nid(zone),
+ shrink_slab(sc->gfp_mask, pgdat->node_id,
memcg, sc->nr_scanned - scanned,
lru_pages);
@@ -2470,7 +2477,7 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc,
/*
* 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
@@ -2489,9 +2496,9 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc,
* the eligible LRU pages were scanned.
*/
if (global_reclaim(sc))
- 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;
@@ -2506,7 +2513,7 @@ 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;
@@ -2903,7 +2910,7 @@ 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)
@@ -2928,11 +2935,11 @@ 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.
*/
- shrink_zone_memcg(zone, memcg, &sc, &lru_pages);
+ shrink_node_memcg(zone->zone_pgdat, memcg, &sc, &lru_pages);
trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed);
@@ -2991,7 +2998,7 @@ 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_list_is_low(lruvec, false))
shrink_active_list(SWAP_CLUSTER_MAX, lruvec,
diff --git a/mm/workingset.c b/mm/workingset.c
index ebe14445809a..de68ad681585 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -218,7 +218,7 @@ void *workingset_eviction(struct address_space *mapping, struct page *page)
VM_BUG_ON_PAGE(page_count(page), page);
VM_BUG_ON_PAGE(!PageLocked(page), page);
- lruvec = mem_cgroup_zone_lruvec(zone, memcg);
+ lruvec = mem_cgroup_lruvec(zone->zone_pgdat, zone, memcg);
eviction = atomic_long_inc_return(&lruvec->inactive_age);
return pack_shadow(memcgid, zone, eviction);
}
@@ -267,7 +267,7 @@ bool workingset_refault(void *shadow)
rcu_read_unlock();
return false;
}
- lruvec = mem_cgroup_zone_lruvec(zone, memcg);
+ lruvec = mem_cgroup_lruvec(zone->zone_pgdat, zone, memcg);
refault = atomic_long_read(&lruvec->inactive_age);
active_file = lruvec_lru_size(lruvec, LRU_ACTIVE_FILE);
rcu_read_unlock();
@@ -319,7 +319,7 @@ void workingset_activation(struct page *page)
memcg = page_memcg_rcu(page);
if (!mem_cgroup_disabled() && !memcg)
goto out;
- lruvec = mem_cgroup_zone_lruvec(page_zone(page), memcg);
+ lruvec = mem_cgroup_lruvec(page_pgdat(page), page_zone(page), memcg);
atomic_long_inc(&lruvec->inactive_age);
out:
rcu_read_unlock();
--
2.6.4