memcg: add inactive_anon_is_low()
The inactive_anon_is_low() is key component of active/inactive anon
balancing on reclaim. However current inactive_anon_is_low() function
only consider global reclaim.
Therefore, we need following ugly scan_global_lru() condition.
if (lru == LRU_ACTIVE_ANON &&
(!scan_global_lru(sc) || inactive_anon_is_low(zone))) {
shrink_active_list(nr_to_scan, zone, sc, priority, file);
return 0;
it cause that memcg reclaim always deactivate pages when shrink_list() is
called. To make mem_cgroup_inactive_anon_is_low() improve active/inactive
anon balancing of memcgroup.
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: "Pekka Enberg" <penberg@cs.helsinki.fi>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 59ac95a..aad9377 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -100,6 +100,8 @@
extern long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone,
int priority, enum lru_list lru);
+int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg,
+ struct zone *zone);
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
extern int do_swap_account;
@@ -251,6 +253,13 @@
{
return false;
}
+
+static inline int
+mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg, struct zone *zone)
+{
+ return 1;
+}
+
#endif /* CONFIG_CGROUP_MEM_CONT */
#endif /* _LINUX_MEMCONTROL_H */
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 457d671..66113284 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -156,6 +156,9 @@
unsigned long last_oom_jiffies;
int obsolete;
atomic_t refcnt;
+
+ unsigned int inactive_ratio;
+
/*
* statistics. This must be placed at the end of memcg.
*/
@@ -431,6 +434,20 @@
return (nr_pages >> priority);
}
+int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg, struct zone *zone)
+{
+ unsigned long active;
+ unsigned long inactive;
+
+ inactive = mem_cgroup_get_all_zonestat(memcg, LRU_INACTIVE_ANON);
+ active = mem_cgroup_get_all_zonestat(memcg, LRU_ACTIVE_ANON);
+
+ if (inactive * memcg->inactive_ratio < active)
+ return 1;
+
+ return 0;
+}
+
unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
struct list_head *dst,
unsigned long *scanned, int order,
@@ -1360,6 +1377,29 @@
return 0;
}
+/*
+ * The inactive anon list should be small enough that the VM never has to
+ * do too much work, but large enough that each inactive page has a chance
+ * to be referenced again before it is swapped out.
+ *
+ * this calculation is straightforward porting from
+ * page_alloc.c::setup_per_zone_inactive_ratio().
+ * it describe more detail.
+ */
+static void mem_cgroup_set_inactive_ratio(struct mem_cgroup *memcg)
+{
+ unsigned int gb, ratio;
+
+ gb = res_counter_read_u64(&memcg->res, RES_LIMIT) >> 30;
+ if (gb)
+ ratio = int_sqrt(10 * gb);
+ else
+ ratio = 1;
+
+ memcg->inactive_ratio = ratio;
+
+}
+
static DEFINE_MUTEX(set_limit_mutex);
static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
@@ -1398,6 +1438,10 @@
GFP_KERNEL, false);
if (!progress) retry_count--;
}
+
+ if (!ret)
+ mem_cgroup_set_inactive_ratio(memcg);
+
return ret;
}
@@ -1982,7 +2026,7 @@
res_counter_init(&mem->res, NULL);
res_counter_init(&mem->memsw, NULL);
}
-
+ mem_cgroup_set_inactive_ratio(mem);
mem->last_scanned_child = NULL;
return &mem->css;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index e2b31a5..b2bc06b 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1310,14 +1310,7 @@
pagevec_release(&pvec);
}
-/**
- * inactive_anon_is_low - check if anonymous pages need to be deactivated
- * @zone: zone to check
- *
- * Returns true if the zone does not have enough inactive anon pages,
- * meaning some active anon pages need to be deactivated.
- */
-static int inactive_anon_is_low(struct zone *zone)
+static int inactive_anon_is_low_global(struct zone *zone)
{
unsigned long active, inactive;
@@ -1330,6 +1323,25 @@
return 0;
}
+/**
+ * inactive_anon_is_low - check if anonymous pages need to be deactivated
+ * @zone: zone to check
+ * @sc: scan control of this context
+ *
+ * Returns true if the zone does not have enough inactive anon pages,
+ * meaning some active anon pages need to be deactivated.
+ */
+static int inactive_anon_is_low(struct zone *zone, struct scan_control *sc)
+{
+ int low;
+
+ if (scan_global_lru(sc))
+ low = inactive_anon_is_low_global(zone);
+ else
+ low = mem_cgroup_inactive_anon_is_low(sc->mem_cgroup, zone);
+ return low;
+}
+
static unsigned long shrink_list(enum lru_list lru, unsigned long nr_to_scan,
struct zone *zone, struct scan_control *sc, int priority)
{
@@ -1340,8 +1352,7 @@
return 0;
}
- if (lru == LRU_ACTIVE_ANON &&
- (!scan_global_lru(sc) || inactive_anon_is_low(zone))) {
+ if (lru == LRU_ACTIVE_ANON && inactive_anon_is_low(zone, sc)) {
shrink_active_list(nr_to_scan, zone, sc, priority, file);
return 0;
}
@@ -1509,9 +1520,7 @@
* Even if we did not try to evict anon pages at all, we want to
* rebalance the anon lru active/inactive ratio.
*/
- if (!scan_global_lru(sc) || inactive_anon_is_low(zone))
- shrink_active_list(SWAP_CLUSTER_MAX, zone, sc, priority, 0);
- else if (!scan_global_lru(sc))
+ if (inactive_anon_is_low(zone, sc))
shrink_active_list(SWAP_CLUSTER_MAX, zone, sc, priority, 0);
throttle_vm_writeout(sc->gfp_mask);
@@ -1807,7 +1816,7 @@
* Do some background aging of the anon list, to give
* pages a chance to be referenced before reclaiming.
*/
- if (inactive_anon_is_low(zone))
+ if (inactive_anon_is_low(zone, &sc))
shrink_active_list(SWAP_CLUSTER_MAX, zone,
&sc, priority, 0);