On Sat 19-01-19 22:30:19, Xiongchun Duan wrote:
> Add a global work to scan offline cgroup and trigger
> offline cgroup force empty.
Why is kswapd not sufficient? And again, a new infrastructure should be
added with its users. Who is supposed to trigger_force_empty?
>
> Signed-off-by: Xiongchun Duan <duanxiongchun@xxxxxxxxxxxxx>
> ---
> mm/memcontrol.c | 12 +++++++++++-
> 1 file changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 4db08b7..fad1aae 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -82,6 +82,7 @@
> int sysctl_cgroup_default_retry_max = 16;
>
> struct timer_list empty_trigger;
> +struct work_struct timer_poll_work;
>
> struct mem_cgroup *root_mem_cgroup __read_mostly;
>
> @@ -320,6 +321,7 @@ void memcg_put_cache_ids(void)
> EXPORT_SYMBOL(memcg_kmem_enabled_key);
>
> struct workqueue_struct *memcg_kmem_cache_wq;
> +struct workqueue_struct *memcg_force_empty_wq;
>
> static int memcg_shrinker_map_size;
> static DEFINE_MUTEX(memcg_shrinker_map_mutex);
> @@ -4573,11 +4575,16 @@ static int mem_cgroup_css_online(struct cgroup_subsys_state *css)
> return 0;
> }
>
> -void empty_timer_trigger(struct timer_list *t)
> +static void trigger_force_empty(struct work_struct *work)
> {
>
> }
>
> +static void empty_timer_trigger(struct timer_list *t)
> +{
> + queue_work(memcg_force_empty_wq, &timer_poll_work);
> +}
> +
> static void mem_cgroup_css_offline(struct cgroup_subsys_state *css)
> {
> struct mem_cgroup *memcg = mem_cgroup_from_css(css);
> @@ -6390,6 +6397,9 @@ static int __init mem_cgroup_init(void)
> memcg_kmem_cache_wq = alloc_workqueue("memcg_kmem_cache", 0, 1);
> BUG_ON(!memcg_kmem_cache_wq);
> #endif
> + memcg_force_empty_wq = alloc_workqueue("memcg_force_empty_wq", 0, 1);
> + BUG_ON(!memcg_force_empty_wq);
> + INIT_WORK(&timer_poll_work, trigger_force_empty);
> timer_setup(&empty_trigger, empty_timer_trigger, 0);
>
> cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL,
> --
> 1.8.3.1
--
Michal Hocko
SUSE Labs
