Commit fee7b548 authored by KAMEZAWA Hiroyuki's avatar KAMEZAWA Hiroyuki Committed by Linus Torvalds
Browse files

memcg: show real limit under hierarchy mode 



Show "real" limit of memcg.  This helps my debugging and maybe useful for
users.

While testing hierarchy like this

	mount -t cgroup none /cgroup -t memory
	mkdir /cgroup/A
	set use_hierarchy==1 to "A"
	mkdir /cgroup/A/01
	mkdir /cgroup/A/01/02
	mkdir /cgroup/A/01/03
	mkdir /cgroup/A/01/03/04
	mkdir /cgroup/A/08
	mkdir /cgroup/A/08/01
	....
and set each own limit to them, "real" limit of each memcg is unclear.
This patch shows real limit by checking all ancestors.

Changelog: (v1) -> (v2)
	- remove "if" and use "min(a,b)"

Acked-by: default avatarBalbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.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 c772be93

mm/memcontrol.c

+35 −0
Original line number Diff line number Diff line
@@ -1782,6 +1782,34 @@ static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, 
	return ret;

}



static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg,

		unsigned long long *mem_limit, unsigned long long *memsw_limit)

{

	struct cgroup *cgroup;

	unsigned long long min_limit, min_memsw_limit, tmp;



	min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT);

	min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT);

	cgroup = memcg->css.cgroup;

	if (!memcg->use_hierarchy)

		goto out;



	while (cgroup->parent) {

		cgroup = cgroup->parent;

		memcg = mem_cgroup_from_cont(cgroup);

		if (!memcg->use_hierarchy)

			break;

		tmp = res_counter_read_u64(&memcg->res, RES_LIMIT);

		min_limit = min(min_limit, tmp);

		tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT);

		min_memsw_limit = min(min_memsw_limit, tmp);

	}

out:

	*mem_limit = min_limit;

	*memsw_limit = min_memsw_limit;

	return;

}



static int mem_cgroup_reset(struct cgroup *cont, unsigned int event)

{

	struct mem_cgroup *mem;
@@ -1855,6 +1883,13 @@ static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft, 
		cb->fill(cb, "unevictable", unevictable * PAGE_SIZE);



	}

	{

		unsigned long long limit, memsw_limit;

		memcg_get_hierarchical_limit(mem_cont, &limit, &memsw_limit);

		cb->fill(cb, "hierarchical_memory_limit", limit);

		if (do_swap_account)

			cb->fill(cb, "hierarchical_memsw_limit", memsw_limit);

	}



#ifdef CONFIG_DEBUG_VM

	cb->fill(cb, "inactive_ratio", calc_inactive_ratio(mem_cont, NULL));

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