Subject: [PATCH bpf-next v9 21/34] bpf: eliminate rlimit-based memory accounting for cgroup storage maps

From: Roman Gushchin <[email-masked]>
Date: Tue, 1 Dec 2020 13:58:47 -0800

Do not use rlimit-based memory accounting for cgroup storage maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <[email-masked]>
Acked-by: Song Liu <[email-masked]>
---
 kernel/bpf/local_storage.c | 21 +--------------------
 1 file changed, 1 insertion(+), 20 deletions(-)

diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index 74dcee8926e5..2d4f9ac12377 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c
@@ -287,8 +287,6 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
 {
 	int numa_node = bpf_map_attr_numa_node(attr);
 	struct bpf_cgroup_storage_map *map;
-	struct bpf_map_memory mem;
-	int ret;
 
 	if (attr->key_size != sizeof(struct bpf_cgroup_storage_key) &&
 	    attr->key_size != sizeof(__u64))
@@ -308,18 +306,10 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
 		/* max_entries is not used and enforced to be 0 */
 		return ERR_PTR(-EINVAL);
 
-	ret = bpf_map_charge_init(&mem, sizeof(struct bpf_cgroup_storage_map));
-	if (ret < 0)
-		return ERR_PTR(ret);
-
 	map = kmalloc_node(sizeof(struct bpf_cgroup_storage_map),
 			   __GFP_ZERO | GFP_USER | __GFP_ACCOUNT, numa_node);
-	if (!map) {
-		bpf_map_charge_finish(&mem);
+	if (!map)
 		return ERR_PTR(-ENOMEM);
-	}
-
-	bpf_map_charge_move(&map->map.memory, &mem);
 
 	/* copy mandatory map attributes */
 	bpf_map_init_from_attr(&map->map, attr);
@@ -508,9 +498,6 @@ struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
 
 	size = bpf_cgroup_storage_calculate_size(map, &pages);
 
-	if (bpf_map_charge_memlock(map, pages))
-		return ERR_PTR(-EPERM);
-
 	storage = bpf_map_kmalloc_node(map, sizeof(struct bpf_cgroup_storage),
 				       gfp, map->numa_node);
 	if (!storage)
@@ -533,7 +520,6 @@ struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
 	return storage;
 
 enomem:
-	bpf_map_uncharge_memlock(map, pages);
 	kfree(storage);
 	return ERR_PTR(-ENOMEM);
 }
@@ -560,16 +546,11 @@ void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage)
 {
 	enum bpf_cgroup_storage_type stype;
 	struct bpf_map *map;
-	u32 pages;
 
 	if (!storage)
 		return;
 
 	map = &storage->map->map;
-
-	bpf_cgroup_storage_calculate_size(map, &pages);
-	bpf_map_uncharge_memlock(map, pages);
-
 	stype = cgroup_storage_type(map);
 	if (stype == BPF_CGROUP_STORAGE_SHARED)
 		call_rcu(&storage->rcu, free_shared_cgroup_storage_rcu);
-- 
2.26.2