On 06.01.2021 01:58, 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 a more general
> name. And this should make the patch adding nr_deferred cleaner and readable and make
> review easier.
>
> Signed-off-by: Yang Shi <shy828301@xxxxxxxxx>
> ---
> include/linux/memcontrol.h | 8 ++---
> mm/memcontrol.c | 6 ++--
> mm/vmscan.c | 66 +++++++++++++++++++-------------------
> 3 files changed, 40 insertions(+), 40 deletions(-)
>
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index d128d2842f22..e05bbe8277cc 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 memcg_shrinker_info {
Reviewing your next patch actively using new fields in this structure,
I strongly insist on renaming it in "struct shrinker_info" instead of that.
Otherwise, lines of function declarations become too long.
> 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 memcg_shrinker_info __rcu *shrinker_info;
>
> 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;
> }
>
> -extern int memcg_alloc_shrinker_maps(struct mem_cgroup *memcg);
> -extern void memcg_free_shrinker_maps(struct mem_cgroup *memcg);
> +extern int memcg_alloc_shrinker_info(struct mem_cgroup *memcg);
> +extern void memcg_free_shrinker_info(struct mem_cgroup *memcg);
> extern void memcg_set_shrinker_bit(struct mem_cgroup *memcg,
> int nid, int shrinker_id);
> #else
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 817dde366258..126f1fd550c8 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -5248,11 +5248,11 @@ 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 memcg_expand_shrinker_maps()
> + * A memcg must be visible for memcg_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 (memcg_alloc_shrinker_maps(memcg)) {
> + if (memcg_alloc_shrinker_info(memcg)) {
> mem_cgroup_id_remove(memcg);
> return -ENOMEM;
> }
> @@ -5316,7 +5316,7 @@ 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);
> - memcg_free_shrinker_maps(memcg);
> + memcg_free_shrinker_info(memcg);
> memcg_free_kmem(memcg);
> mem_cgroup_free(memcg);
> }
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index 9761c7c27412..0033659abf9e 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -187,20 +187,20 @@ static DECLARE_RWSEM(shrinker_rwsem);
> #ifdef CONFIG_MEMCG
> static int shrinker_nr_max;
>
> -static void memcg_free_shrinker_map_rcu(struct rcu_head *head)
> +static void memcg_free_shrinker_info_rcu(struct rcu_head *head)
> {
> - kvfree(container_of(head, struct memcg_shrinker_map, rcu));
> + kvfree(container_of(head, struct memcg_shrinker_info, rcu));
> }
>
> -static int memcg_expand_one_shrinker_map(struct mem_cgroup *memcg,
> - int size, int old_size)
> +static int memcg_expand_one_shrinker_info(struct mem_cgroup *memcg,
> + int size, int old_size)
> {
> - struct memcg_shrinker_map *new, *old;
> + struct memcg_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;
> @@ -213,17 +213,17 @@ static int memcg_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, memcg_free_shrinker_map_rcu);
> + rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_info, new);
> + call_rcu(&old->rcu, memcg_free_shrinker_info_rcu);
> }
>
> return 0;
> }
>
> -void memcg_free_shrinker_maps(struct mem_cgroup *memcg)
> +void memcg_free_shrinker_info(struct mem_cgroup *memcg)
> {
> struct mem_cgroup_per_node *pn;
> - struct memcg_shrinker_map *map;
> + struct memcg_shrinker_info *info;
> int nid;
>
> if (mem_cgroup_is_root(memcg))
> @@ -231,16 +231,16 @@ void memcg_free_shrinker_maps(struct mem_cgroup *memcg)
>
> for_each_node(nid) {
> pn = mem_cgroup_nodeinfo(memcg, nid);
> - map = rcu_dereference_protected(pn->shrinker_map, true);
> - if (map)
> - kvfree(map);
> - rcu_assign_pointer(pn->shrinker_map, NULL);
> + info = rcu_dereference_protected(pn->shrinker_info, true);
> + if (info)
> + kvfree(info);
> + rcu_assign_pointer(pn->shrinker_info, NULL);
> }
> }
>
> -int memcg_alloc_shrinker_maps(struct mem_cgroup *memcg)
> +int memcg_alloc_shrinker_info(struct mem_cgroup *memcg)
> {
> - struct memcg_shrinker_map *map;
> + struct memcg_shrinker_info *info;
> int nid, size, ret = 0;
>
> if (mem_cgroup_is_root(memcg))
> @@ -249,20 +249,20 @@ int memcg_alloc_shrinker_maps(struct mem_cgroup *memcg)
> down_read(&shrinker_rwsem);
> size = DIV_ROUND_UP(shrinker_nr_max, BITS_PER_LONG) * sizeof(unsigned long);
> for_each_node(nid) {
> - map = kvzalloc(sizeof(*map) + size, GFP_KERNEL);
> - if (!map) {
> - memcg_free_shrinker_maps(memcg);
> + info = kvzalloc(sizeof(*info) + size, GFP_KERNEL);
> + if (!info) {
> + memcg_free_shrinker_info(memcg);
> ret = -ENOMEM;
> break;
> }
> - rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_map, map);
> + rcu_assign_pointer(memcg->nodeinfo[nid]->shrinker_info, info);
> }
> up_read(&shrinker_rwsem);
>
> return ret;
> }
>
> -static int memcg_expand_shrinker_maps(int new_id)
> +static int memcg_expand_shrinker_info(int new_id)
> {
> int size, old_size, ret = 0;
> struct mem_cgroup *memcg;
> @@ -279,7 +279,7 @@ static int memcg_expand_shrinker_maps(int new_id)
> do {
> if (mem_cgroup_is_root(memcg))
> continue;
> - ret = memcg_expand_one_shrinker_map(memcg, size, old_size);
> + ret = memcg_expand_one_shrinker_info(memcg, size, old_size);
> if (ret) {
> mem_cgroup_iter_break(NULL, memcg);
> goto out;
> @@ -293,13 +293,13 @@ static int memcg_expand_shrinker_maps(int new_id)
> void memcg_set_shrinker_bit(struct mem_cgroup *memcg, int nid, int shrinker_id)
> {
> if (shrinker_id >= 0 && memcg && !mem_cgroup_is_root(memcg)) {
> - struct memcg_shrinker_map *map;
> + struct memcg_shrinker_info *info;
>
> rcu_read_lock();
> - map = rcu_dereference(memcg->nodeinfo[nid]->shrinker_map);
> + info = rcu_dereference(memcg->nodeinfo[nid]->shrinker_info);
> /* Pairs with smp mb in shrink_slab() */
> smp_mb__before_atomic();
> - set_bit(shrinker_id, map->map);
> + set_bit(shrinker_id, info->map);
> rcu_read_unlock();
> }
> }
> @@ -330,7 +330,7 @@ static int prealloc_memcg_shrinker(struct shrinker *shrinker)
> goto unlock;
>
> if (id >= shrinker_nr_max) {
> - if (memcg_expand_shrinker_maps(id)) {
> + if (memcg_expand_shrinker_info(id)) {
> idr_remove(&shrinker_idr, id);
> goto unlock;
> }
> @@ -666,7 +666,7 @@ static unsigned long do_shrink_slab(struct shrink_control *shrinkctl,
> static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int nid,
> struct mem_cgroup *memcg, int priority)
> {
> - struct memcg_shrinker_map *map;
> + struct memcg_shrinker_info *info;
> unsigned long ret, freed = 0;
> int i;
>
> @@ -676,12 +676,12 @@ static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int nid,
> if (!down_read_trylock(&shrinker_rwsem))
> return 0;
>
> - map = rcu_dereference_protected(memcg->nodeinfo[nid]->shrinker_map,
> - true);
> - if (unlikely(!map))
> + info = rcu_dereference_protected(memcg->nodeinfo[nid]->shrinker_info,
> + true);
> + if (unlikely(!info))
> goto unlock;
>
> - for_each_set_bit(i, map->map, shrinker_nr_max) {
> + for_each_set_bit(i, info->map, shrinker_nr_max) {
> struct shrink_control sc = {
> .gfp_mask = gfp_mask,
> .nid = nid,
> @@ -692,7 +692,7 @@ static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int nid,
> shrinker = idr_find(&shrinker_idr, i);
> if (unlikely(!shrinker || shrinker == SHRINKER_REGISTERING)) {
> if (!shrinker)
> - clear_bit(i, map->map);
> + clear_bit(i, info->map);
> continue;
> }
>
> @@ -703,7 +703,7 @@ static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int nid,
>
> ret = do_shrink_slab(&sc, shrinker, priority);
> if (ret == SHRINK_EMPTY) {
> - clear_bit(i, map->map);
> + clear_bit(i, info->map);
> /*
> * After the shrinker reported that it had no objects to
> * free, but before we cleared the corresponding bit in
>
