Re: [v8 2/4] mm, oom: cgroup-aware OOM killer

David Rientjes
2017-09-13T20:46:51Z

On Mon, 11 Sep 2017, Roman Gushchin wrote:

> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 15af3da5af02..da2b12ea4667 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -2661,6 +2661,231 @@ static inline bool memcg_has_children(struct mem_cgroup *memcg)
> return ret;
> }
>
> +static long memcg_oom_badness(struct mem_cgroup *memcg,
> + const nodemask_t *nodemask,
> + unsigned long totalpages)
> +{
> + long points = 0;
> + int nid;
> + pg_data_t *pgdat;
> +
> + /*
> + * We don't have necessary stats for the root memcg,
> + * so we define it's oom_score as the maximum oom_score
> + * of the belonging tasks.
> + */
> + if (memcg == root_mem_cgroup) {
> + struct css_task_iter it;
> + struct task_struct *task;
> + long score, max_score = 0;
> +
> + css_task_iter_start(&memcg->css, 0, &it);
> + while ((task = css_task_iter_next(&it))) {
> + score = oom_badness(task, memcg, nodemask,
> + totalpages);
> + if (max_score > score)

score > max_score

> + max_score = score;
> + }
> + css_task_iter_end(&it);
> +
> + return max_score;
> + }
> +
> + for_each_node_state(nid, N_MEMORY) {
> + if (nodemask && !node_isset(nid, *nodemask))
> + continue;
> +
> + points += mem_cgroup_node_nr_lru_pages(memcg, nid,
> + LRU_ALL_ANON | BIT(LRU_UNEVICTABLE));
> +
> + pgdat = NODE_DATA(nid);
> + points += lruvec_page_state(mem_cgroup_lruvec(pgdat, memcg),
> + NR_SLAB_UNRECLAIMABLE);
> + }
> +
> + points += memcg_page_state(memcg, MEMCG_KERNEL_STACK_KB) /
> + (PAGE_SIZE / 1024);
> + points += memcg_page_state(memcg, MEMCG_SOCK);
> + points += memcg_page_state(memcg, MEMCG_SWAP);
> +
> + return points;
> +}