Commit 14797e23 authored by KOSAKI Motohiro's avatar KOSAKI Motohiro Committed by Linus Torvalds
Browse files

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: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: default avatarRik van Riel <riel@redhat.com>
Signed-off-by: default avatarKOSAKI 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 54992762

include/linux/memcontrol.h

+9 −0
Original line number Diff line number Diff line
@@ -100,6 +100,8 @@ extern void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, 


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 @@ static inline bool mem_cgroup_oom_called(struct task_struct *task) 
{

	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 */

mm/memcontrol.c

+45 −1
Original line number Diff line number Diff line
@@ -156,6 +156,9 @@ struct mem_cgroup { 
	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 @@ long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone, 
	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 @@ int mem_cgroup_shrink_usage(struct mm_struct *mm, gfp_t gfp_mask) 
	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 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, 
				GFP_KERNEL, false);

  		if (!progress)			retry_count--;

	}



	if (!ret)

		mem_cgroup_set_inactive_ratio(memcg);



	return ret;

}
@@ -1982,7 +2026,7 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) 
		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;

mm/vmscan.c

+23 −14
Original line number Diff line number Diff line
@@ -1310,14 +1310,7 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone, 
	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 @@ static int inactive_anon_is_low(struct zone *zone) 
	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 @@ static unsigned long shrink_list(enum lru_list lru, unsigned long nr_to_scan, 
		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 @@ static void shrink_zone(int priority, struct zone *zone, 
	 * 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 @@ loop_again: 
			 * 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);

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