diff options
Diffstat (limited to 'include/linux/bpf_local_storage.h')
-rw-r--r-- | include/linux/bpf_local_storage.h | 30 |
1 files changed, 28 insertions, 2 deletions
diff --git a/include/linux/bpf_local_storage.h b/include/linux/bpf_local_storage.h index 173ec7f43ed1..dcddb0aef7d8 100644 --- a/include/linux/bpf_local_storage.h +++ b/include/linux/bpf_local_storage.h @@ -129,10 +129,36 @@ bpf_local_storage_map_alloc(union bpf_attr *attr, struct bpf_local_storage_cache *cache, bool bpf_ma); -struct bpf_local_storage_data * +void __bpf_local_storage_insert_cache(struct bpf_local_storage *local_storage, + struct bpf_local_storage_map *smap, + struct bpf_local_storage_elem *selem); +/* If cacheit_lockit is false, this lookup function is lockless */ +static inline struct bpf_local_storage_data * bpf_local_storage_lookup(struct bpf_local_storage *local_storage, struct bpf_local_storage_map *smap, - bool cacheit_lockit); + bool cacheit_lockit) +{ + struct bpf_local_storage_data *sdata; + struct bpf_local_storage_elem *selem; + + /* Fast path (cache hit) */ + sdata = rcu_dereference_check(local_storage->cache[smap->cache_idx], + bpf_rcu_lock_held()); + if (sdata && rcu_access_pointer(sdata->smap) == smap) + return sdata; + + /* Slow path (cache miss) */ + hlist_for_each_entry_rcu(selem, &local_storage->list, snode, + rcu_read_lock_trace_held()) + if (rcu_access_pointer(SDATA(selem)->smap) == smap) + break; + + if (!selem) + return NULL; + if (cacheit_lockit) + __bpf_local_storage_insert_cache(local_storage, smap, selem); + return SDATA(selem); +} void bpf_local_storage_destroy(struct bpf_local_storage *local_storage); |