Subject: [PATCH bpf-next v9 22/34] bpf: eliminate rlimit-based memory accounting for devmap maps

From: Roman Gushchin <[email-masked]>
Date: Tue, 1 Dec 2020 13:58:48 -0800

Do not use rlimit-based memory accounting for devmap 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/devmap.c | 18 ++----------------
 1 file changed, 2 insertions(+), 16 deletions(-)

diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index b43ab247302d..f6e9c68afdd4 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -109,8 +109,6 @@ static inline struct hlist_head *dev_map_index_hash(struct bpf_dtab *dtab,
 static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
 {
 	u32 valsize = attr->value_size;
-	u64 cost = 0;
-	int err;
 
 	/* check sanity of attributes. 2 value sizes supported:
 	 * 4 bytes: ifindex
@@ -135,21 +133,13 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
 
 		if (!dtab->n_buckets) /* Overflow check */
 			return -EINVAL;
-		cost += (u64) sizeof(struct hlist_head) * dtab->n_buckets;
-	} else {
-		cost += (u64) dtab->map.max_entries * sizeof(struct bpf_dtab_netdev *);
 	}
 
-	/* if map size is larger than memlock limit, reject it */
-	err = bpf_map_charge_init(&dtab->map.memory, cost);
-	if (err)
-		return -EINVAL;
-
 	if (attr->map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
 		dtab->dev_index_head = dev_map_create_hash(dtab->n_buckets,
 							   dtab->map.numa_node);
 		if (!dtab->dev_index_head)
-			goto free_charge;
+			return -ENOMEM;
 
 		spin_lock_init(&dtab->index_lock);
 	} else {
@@ -157,14 +147,10 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
 						      sizeof(struct bpf_dtab_netdev *),
 						      dtab->map.numa_node);
 		if (!dtab->netdev_map)
-			goto free_charge;
+			return -ENOMEM;
 	}
 
 	return 0;
-
-free_charge:
-	bpf_map_charge_finish(&dtab->map.memory);
-	return -ENOMEM;
 }
 
 static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
-- 
2.26.2