On Tue, Feb 09, 2021 at 09:46:39AM -0800, Yang Shi wrote:
> The following patch is going to add nr_deferred into shrinker_map, the change will
> make shrinker_map not only include map anymore, so rename it to "memcg_shrinker_info".
> And this should make the patch adding nr_deferred cleaner and readable and make
> review easier. Also remove the "memcg_" prefix.
>
> Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
> Acked-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
> Signed-off-by: Yang Shi <shy828301@xxxxxxxxx>
> ---
> include/linux/memcontrol.h | 8 ++---
> mm/memcontrol.c | 6 ++--
> mm/vmscan.c | 62 +++++++++++++++++++-------------------
> 3 files changed, 38 insertions(+), 38 deletions(-)
>
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index 1739f17e0939..4c9253896e25 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -96,7 +96,7 @@ struct lruvec_stat {
> * Bitmap of shrinker::id corresponding to memcg-aware shrinkers,
> * which have elements charged to this memcg.
> */
> -struct memcg_shrinker_map {
> +struct shrinker_info {
> struct rcu_head rcu;
> unsigned long map[];
> };
> @@ -118,7 +118,7 @@ struct mem_cgroup_per_node {
>
> struct mem_cgroup_reclaim_iter iter;
>
> - struct memcg_shrinker_map __rcu *shrinker_map;
> + struct shrinker_info __rcu *shrinker_info;
Nice!
I really like how it looks now in comparison to the v1. Thank you for
working on it!
>
> struct rb_node tree_node; /* RB tree node */
> unsigned long usage_in_excess;/* Set to the value by which */
> @@ -1581,8 +1581,8 @@ static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
> return false;
> }
>
> -int alloc_shrinker_maps(struct mem_cgroup *memcg);
> -void free_shrinker_maps(struct mem_cgroup *memcg);
> +int alloc_shrinker_info(struct mem_cgroup *memcg);
> +void free_shrinker_info(struct mem_cgroup *memcg);
> void set_shrinker_bit(struct mem_cgroup *memcg, int nid, int shrinker_id);
> #else
> #define mem_cgroup_sockets_enabled 0
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index f5c9a0d2160b..f64ad0d044d9 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -5246,11 +5246,11 @@ static int mem_cgroup_css_online(struct cgroup_subsys_state *css)
> struct mem_cgroup *memcg = mem_cgroup_from_css(css);
>
> /*
> - * A memcg must be visible for expand_shrinker_maps()
> + * A memcg must be visible for expand_shrinker_info()
> * by the time the maps are allocated. So, we allocate maps
> * here, when for_each_mem_cgroup() can't skip it.
> */
> - if (alloc_shrinker_maps(memcg)) {
> + if (alloc_shrinker_info(memcg)) {
> mem_cgroup_id_remove(memcg);
> return -ENOMEM;
> }
> @@ -5314,7 +5314,7 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
> vmpressure_cleanup(&memcg->vmpressure);
> cancel_work_sync(&memcg->high_work);
> mem_cgroup_remove_from_trees(memcg);
> - free_shrinker_maps(memcg);
> + free_shrinker_info(memcg);
> memcg_free_kmem(memcg);
> mem_cgroup_free(memcg);
> }
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index 641077b09e5d..9436f9246d32 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -190,20 +190,20 @@ static int shrinker_nr_max;
> #define NR_MAX_TO_SHR_MAP_SIZE(nr_max) \
> (DIV_ROUND_UP(nr_max, BITS_PER_LONG) * sizeof(unsigned long))
>
> -static void free_shrinker_map_rcu(struct rcu_head *head)
> +static void free_shrinker_info_rcu(struct rcu_head *head)
> {
> - kvfree(container_of(head, struct memcg_shrinker_map, rcu));
> + kvfree(container_of(head, struct shrinker_info, rcu));
> }
>
> -static int expand_one_shrinker_map(struct mem_cgroup *memcg,
> +static int expand_one_shrinker_info(struct mem_cgroup *memcg,
> int size, int old_size)
> {
> - struct memcg_shrinker_map *new, *old;
> + struct shrinker_info *new, *old;
> int nid;
>
> for_each_node(nid) {
> old = rcu_dereference_protected(
> - mem_cgroup_nodeinfo(memcg, nid)->shrinker_map, true);
> + mem_cgroup_nodeinfo(memcg, nid)->shrinker_info, true);
> /* Not yet online memcg */
> if (!old)
> return 0;
> @@ -216,17 +216,17 @@ static int expand_one_shrinker_map(struct mem_cgroup *memcg,
> memset(new->map, (int)0xff, old_size);
> memset((void *)new->map + old_size, 0, size - old_size);
>
> - rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_map, new);
> - call_rcu(&old->rcu, free_shrinker_map_rcu);
> + rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_info, new);
> + call_rcu(&old->rcu, free_shrinker_info_rcu);
Why not use kvfree_rcu() and get rid of free_shrinker_info_rcu() callback?
Aside from this minor thing, the patch looks good to me. Please, feel free to add
Acked-by: Roman Gushchin <guro@xxxxxx>
Thanks!
