bpf: Bloom filter map naming fixups

This patch has two changes in the kernel bloom filter map
implementation:

1) Change the names of map-ops functions to include the
"bloom_map" prefix.

As Martin pointed out on a previous patchset, having generic
map-ops names may be confusing in tracing and in perf-report.

2) Drop the "& 0xF" when getting nr_hash_funcs, since we
already ascertain that no other bits in map_extra beyond the
first 4 bits can be set.

Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211029224909.1721024-2-joannekoong@fb.com

diff --git a/kernel/bpf/bloom_filter.c b/kernel/bpf/bloom_filter.c
index 7c50232b7571f3f038dd45b5c0bd7289125e6d43..073c2f2cab8b4f492dc58f46ad78302f3ab0f7da 100644 (file)
--- a/kernel/bpf/bloom_filter.c
+++ b/kernel/bpf/bloom_filter.c
@@ -40,7 +40,7 @@ static u32 hash(struct bpf_bloom_filter *bloom, void *value,
        return h & bloom->bitset_mask;
 }
 
-static int peek_elem(struct bpf_map *map, void *value)
+static int bloom_map_peek_elem(struct bpf_map *map, void *value)
 {
        struct bpf_bloom_filter *bloom =
                container_of(map, struct bpf_bloom_filter, map);
@@ -55,7 +55,7 @@ static int peek_elem(struct bpf_map *map, void *value)
        return 0;
 }
 
-static int push_elem(struct bpf_map *map, void *value, u64 flags)
+static int bloom_map_push_elem(struct bpf_map *map, void *value, u64 flags)
 {
        struct bpf_bloom_filter *bloom =
                container_of(map, struct bpf_bloom_filter, map);
@@ -72,12 +72,12 @@ static int push_elem(struct bpf_map *map, void *value, u64 flags)
        return 0;
 }
 
-static int pop_elem(struct bpf_map *map, void *value)
+static int bloom_map_pop_elem(struct bpf_map *map, void *value)
 {
        return -EOPNOTSUPP;
 }
 
-static struct bpf_map *map_alloc(union bpf_attr *attr)
+static struct bpf_map *bloom_map_alloc(union bpf_attr *attr)
 {
        u32 bitset_bytes, bitset_mask, nr_hash_funcs, nr_bits;
        int numa_node = bpf_map_attr_numa_node(attr);
@@ -90,11 +90,13 @@ static struct bpf_map *map_alloc(union bpf_attr *attr)
            attr->max_entries == 0 ||
            attr->map_flags & ~BLOOM_CREATE_FLAG_MASK ||
            !bpf_map_flags_access_ok(attr->map_flags) ||
+           /* The lower 4 bits of map_extra (0xF) specify the number
+            * of hash functions
+            */
            (attr->map_extra & ~0xF))
                return ERR_PTR(-EINVAL);
 
-       /* The lower 4 bits of map_extra specify the number of hash functions */
-       nr_hash_funcs = attr->map_extra & 0xF;
+       nr_hash_funcs = attr->map_extra;
        if (nr_hash_funcs == 0)
                /* Default to using 5 hash functions if unspecified */
                nr_hash_funcs = 5;
@@ -150,7 +152,7 @@ static struct bpf_map *map_alloc(union bpf_attr *attr)
        return &bloom->map;
 }
 
-static void map_free(struct bpf_map *map)
+static void bloom_map_free(struct bpf_map *map)
 {
        struct bpf_bloom_filter *bloom =
                container_of(map, struct bpf_bloom_filter, map);
@@ -158,38 +160,39 @@ static void map_free(struct bpf_map *map)
        bpf_map_area_free(bloom);
 }
 
-static void *lookup_elem(struct bpf_map *map, void *key)
+static void *bloom_map_lookup_elem(struct bpf_map *map, void *key)
 {
        /* The eBPF program should use map_peek_elem instead */
        return ERR_PTR(-EINVAL);
 }
 
-static int update_elem(struct bpf_map *map, void *key,
-                      void *value, u64 flags)
+static int bloom_map_update_elem(struct bpf_map *map, void *key,
+                                void *value, u64 flags)
 {
        /* The eBPF program should use map_push_elem instead */
        return -EINVAL;
 }
 
-static int check_btf(const struct bpf_map *map, const struct btf *btf,
-                    const struct btf_type *key_type,
-                    const struct btf_type *value_type)
+static int bloom_map_check_btf(const struct bpf_map *map,
+                              const struct btf *btf,
+                              const struct btf_type *key_type,
+                              const struct btf_type *value_type)
 {
        /* Bloom filter maps are keyless */
        return btf_type_is_void(key_type) ? 0 : -EINVAL;
 }
 
-static int bpf_bloom_btf_id;
+static int bpf_bloom_map_btf_id;
 const struct bpf_map_ops bloom_filter_map_ops = {
        .map_meta_equal = bpf_map_meta_equal,
-       .map_alloc = map_alloc,
-       .map_free = map_free,
-       .map_push_elem = push_elem,
-       .map_peek_elem = peek_elem,
-       .map_pop_elem = pop_elem,
-       .map_lookup_elem = lookup_elem,
-       .map_update_elem = update_elem,
-       .map_check_btf = check_btf,
+       .map_alloc = bloom_map_alloc,
+       .map_free = bloom_map_free,
+       .map_push_elem = bloom_map_push_elem,
+       .map_peek_elem = bloom_map_peek_elem,
+       .map_pop_elem = bloom_map_pop_elem,
+       .map_lookup_elem = bloom_map_lookup_elem,
+       .map_update_elem = bloom_map_update_elem,
+       .map_check_btf = bloom_map_check_btf,
        .map_btf_name = "bpf_bloom_filter",
-       .map_btf_id = &bpf_bloom_btf_id,
+       .map_btf_id = &bpf_bloom_map_btf_id,
 };