[PATCH bpf-next v8 23/34] bpf: eliminate rlimit-based memory accounting for hashtab maps

Roman Gushchin
2020-11-25T03:03:48Z

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 <guro@fb.com>
Acked-by: Song Liu <songliubraving@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