diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 069bc202ffe340fb69e9e3dc9414fe8b03043bd1..63c3cd454d1edbfdb9b37578e14c7c39fc694135 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -925,6 +925,14 @@ struct cgroup_subsys blkio_cgrp_subsys = { .css_free = blkcg_css_free, .can_attach = blkcg_can_attach, .base_cftypes = blkcg_files, +#ifdef CONFIG_MEMCG + /* + * This ensures that, if available, memcg is automatically enabled + * together on the default hierarchy so that the owner cgroup can + * be retrieved from writeback pages. + */ + .depends_on = 1 << memory_cgrp_id, +#endif }; EXPORT_SYMBOL_GPL(blkio_cgrp_subsys); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index a2c7bcb0e6ebf10672f91b8117aef69d08b41ade..db536e90c8ee852b54406051b3b58b525d8a51ce 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -6407,6 +6407,29 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css) __mem_cgroup_free(memcg); } +/** + * mem_cgroup_css_reset - reset the states of a mem_cgroup + * @css: the target css + * + * Reset the states of the mem_cgroup associated with @css. This is + * invoked when the userland requests disabling on the default hierarchy + * but the memcg is pinned through dependency. The memcg should stop + * applying policies and should revert to the vanilla state as it may be + * made visible again. + * + * The current implementation only resets the essential configurations. + * This needs to be expanded to cover all the visible parts. + */ +static void mem_cgroup_css_reset(struct cgroup_subsys_state *css) +{ + struct mem_cgroup *memcg = mem_cgroup_from_css(css); + + mem_cgroup_resize_limit(memcg, ULLONG_MAX); + mem_cgroup_resize_memsw_limit(memcg, ULLONG_MAX); + memcg_update_kmem_limit(memcg, ULLONG_MAX); + res_counter_set_soft_limit(&memcg->res, ULLONG_MAX); +} + #ifdef CONFIG_MMU /* Handlers for move charge at task migration. */ #define PRECHARGE_COUNT_AT_ONCE 256 @@ -7019,6 +7042,7 @@ struct cgroup_subsys memory_cgrp_subsys = { .css_online = mem_cgroup_css_online, .css_offline = mem_cgroup_css_offline, .css_free = mem_cgroup_css_free, + .css_reset = mem_cgroup_css_reset, .can_attach = mem_cgroup_can_attach, .cancel_attach = mem_cgroup_cancel_attach, .attach = mem_cgroup_move_task,