diff options
Diffstat (limited to 'kernel/bpf/bpf_local_storage.c')
| -rw-r--r-- | kernel/bpf/bpf_local_storage.c | 38 |
1 files changed, 15 insertions, 23 deletions
diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c index 7e6a0af0afc1..fa56c30833ff 100644 --- a/kernel/bpf/bpf_local_storage.c +++ b/kernel/bpf/bpf_local_storage.c @@ -81,9 +81,7 @@ bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner, return NULL; if (smap->bpf_ma) { - migrate_disable(); selem = bpf_mem_cache_alloc_flags(&smap->selem_ma, gfp_flags); - migrate_enable(); if (selem) /* Keep the original bpf_map_kzalloc behavior * before started using the bpf_mem_cache_alloc. @@ -174,17 +172,14 @@ static void bpf_local_storage_free(struct bpf_local_storage *local_storage, return; } - if (smap) { - migrate_disable(); + if (smap) bpf_mem_cache_free(&smap->storage_ma, local_storage); - migrate_enable(); - } else { + else /* smap could be NULL if the selem that triggered * this 'local_storage' creation had been long gone. * In this case, directly do call_rcu(). */ call_rcu(&local_storage->rcu, bpf_local_storage_free_rcu); - } } /* rcu tasks trace callback for bpf_ma == false */ @@ -217,7 +212,10 @@ static void bpf_selem_free_rcu(struct rcu_head *rcu) selem = container_of(rcu, struct bpf_local_storage_elem, rcu); /* The bpf_local_storage_map_free will wait for rcu_barrier */ smap = rcu_dereference_check(SDATA(selem)->smap, 1); + + migrate_disable(); bpf_obj_free_fields(smap->map.record, SDATA(selem)->data); + migrate_enable(); bpf_mem_cache_raw_free(selem); } @@ -256,9 +254,7 @@ void bpf_selem_free(struct bpf_local_storage_elem *selem, * bpf_mem_cache_free will be able to reuse selem * immediately. */ - migrate_disable(); bpf_mem_cache_free(&smap->selem_ma, selem); - migrate_enable(); return; } @@ -497,15 +493,11 @@ int bpf_local_storage_alloc(void *owner, if (err) return err; - if (smap->bpf_ma) { - migrate_disable(); + if (smap->bpf_ma) storage = bpf_mem_cache_alloc_flags(&smap->storage_ma, gfp_flags); - migrate_enable(); - } else { + else storage = bpf_map_kzalloc(&smap->map, sizeof(*storage), gfp_flags | __GFP_NOWARN); - } - if (!storage) { err = -ENOMEM; goto uncharge; @@ -841,8 +833,12 @@ bpf_local_storage_map_alloc(union bpf_attr *attr, smap->elem_size = offsetof(struct bpf_local_storage_elem, sdata.data[attr->value_size]); - smap->bpf_ma = bpf_ma; - if (bpf_ma) { + /* In PREEMPT_RT, kmalloc(GFP_ATOMIC) is still not safe in non + * preemptible context. Thus, enforce all storages to use + * bpf_mem_alloc when CONFIG_PREEMPT_RT is enabled. + */ + smap->bpf_ma = IS_ENABLED(CONFIG_PREEMPT_RT) ? true : bpf_ma; + if (smap->bpf_ma) { err = bpf_mem_alloc_init(&smap->selem_ma, smap->elem_size, false); if (err) goto free_smap; @@ -898,15 +894,11 @@ void bpf_local_storage_map_free(struct bpf_map *map, while ((selem = hlist_entry_safe( rcu_dereference_raw(hlist_first_rcu(&b->list)), struct bpf_local_storage_elem, map_node))) { - if (busy_counter) { - migrate_disable(); + if (busy_counter) this_cpu_inc(*busy_counter); - } bpf_selem_unlink(selem, true); - if (busy_counter) { + if (busy_counter) this_cpu_dec(*busy_counter); - migrate_enable(); - } cond_resched_rcu(); } rcu_read_unlock(); |