[PATCH bpf-next v7 23/34] bpf: eliminate rlimit-based memory accounting for hashtab maps

[Roman Gushchin]

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

Signed-off-by: Roman Gushchin <g...@fb.com>
Acked-by: Song Liu <songliubrav...@fb.com>
---
 kernel/bpf/hashtab.c | 19 +------------------
 1 file changed, 1 insertion(+), 18 deletions(-)

diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 2b8bbdbec872..eed12427ddd5 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -443,7 +443,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
        bool prealloc = !(attr->map_flags & BPF_F_NO_PREALLOC);
        struct bpf_htab *htab;
        int err, i;
-       u64 cost;
 
        htab = kzalloc(sizeof(*htab), GFP_USER | __GFP_ACCOUNT);
        if (!htab)
@@ -481,26 +480,12 @@ static struct bpf_map *htab_map_alloc(union bpf_attr 
*attr)
            htab->n_buckets > U32_MAX / sizeof(struct bucket))
                goto free_htab;
 
-       cost = (u64) htab->n_buckets * sizeof(struct bucket) +
-              (u64) htab->elem_size * htab->map.max_entries;
-
-       if (percpu)
-               cost += (u64) round_up(htab->map.value_size, 8) *
-                       num_possible_cpus() * htab->map.max_entries;
-       else
-              cost += (u64) htab->elem_size * num_possible_cpus();
-
-       /* if map size is larger than memlock limit, reject it */
-       err = bpf_map_charge_init(&htab->map.memory, cost);
-       if (err)
-               goto free_htab;
-
        err = -ENOMEM;
        htab->buckets = bpf_map_area_alloc(htab->n_buckets *
                                           sizeof(struct bucket),
                                           htab->map.numa_node);
        if (!htab->buckets)
-               goto free_charge;
+               goto free_htab;
 
        for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++) {
                htab->map_locked[i] = __alloc_percpu_gfp(sizeof(int),
@@ -539,8 +524,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
        for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++)
                free_percpu(htab->map_locked[i]);
        bpf_map_area_free(htab->buckets);
-free_charge:
-       bpf_map_charge_finish(&htab->map.memory);
 free_htab:
        lockdep_unregister_key(&htab->lockdep_key);
        kfree(htab);
-- 
2.26.2