diff options
Diffstat (limited to 'net/ipv4/fib_hash.c')
| -rw-r--r-- | net/ipv4/fib_hash.c | 52 |
1 files changed, 23 insertions, 29 deletions
diff --git a/net/ipv4/fib_hash.c b/net/ipv4/fib_hash.c index 83cca68e259..10001aa4069 100644 --- a/net/ipv4/fib_hash.c +++ b/net/ipv4/fib_hash.c @@ -54,23 +54,23 @@ struct fib_node { struct fib_alias fn_embedded_alias; }; +#define EMBEDDED_HASH_SIZE (L1_CACHE_BYTES / sizeof(struct hlist_head)) + struct fn_zone { struct fn_zone *fz_next; /* Next not empty zone */ struct hlist_head *fz_hash; /* Hash table pointer */ - int fz_nent; /* Number of entries */ - - int fz_divisor; /* Hash divisor */ u32 fz_hashmask; /* (fz_divisor - 1) */ -#define FZ_HASHMASK(fz) ((fz)->fz_hashmask) - int fz_order; /* Zone order */ - __be32 fz_mask; + u8 fz_order; /* Zone order (0..32) */ + u8 fz_revorder; /* 32 - fz_order */ + __be32 fz_mask; /* inet_make_mask(order) */ #define FZ_MASK(fz) ((fz)->fz_mask) -}; -/* NOTE. On fast computers evaluation of fz_hashmask and fz_mask - * can be cheaper than memory lookup, so that FZ_* macros are used. - */ + struct hlist_head fz_embedded_hash[EMBEDDED_HASH_SIZE]; + + int fz_nent; /* Number of entries */ + int fz_divisor; /* Hash size (mask+1) */ +}; struct fn_hash { struct fn_zone *fn_zones[33]; @@ -79,11 +79,11 @@ struct fn_hash { static inline u32 fn_hash(__be32 key, struct fn_zone *fz) { - u32 h = ntohl(key)>>(32 - fz->fz_order); + u32 h = ntohl(key) >> fz->fz_revorder; h ^= (h>>20); h ^= (h>>10); h ^= (h>>5); - h &= FZ_HASHMASK(fz); + h &= fz->fz_hashmask; return h; } @@ -147,14 +147,14 @@ static void fn_rehash_zone(struct fn_zone *fz) int old_divisor, new_divisor; u32 new_hashmask; - old_divisor = fz->fz_divisor; + new_divisor = old_divisor = fz->fz_divisor; switch (old_divisor) { - case 16: - new_divisor = 256; + case EMBEDDED_HASH_SIZE: + new_divisor *= EMBEDDED_HASH_SIZE; break; - case 256: - new_divisor = 1024; + case EMBEDDED_HASH_SIZE*EMBEDDED_HASH_SIZE: + new_divisor *= (EMBEDDED_HASH_SIZE/2); break; default: if ((old_divisor << 1) > FZ_MAX_DIVISOR) { @@ -184,7 +184,8 @@ static void fn_rehash_zone(struct fn_zone *fz) fib_hash_genid++; write_unlock_bh(&fib_hash_lock); - fz_hash_free(old_ht, old_divisor); + if (old_ht != fz->fz_embedded_hash) + fz_hash_free(old_ht, old_divisor); } } @@ -210,18 +211,11 @@ fn_new_zone(struct fn_hash *table, int z) if (!fz) return NULL; - if (z) { - fz->fz_divisor = 16; - } else { - fz->fz_divisor = 1; - } - fz->fz_hashmask = (fz->fz_divisor - 1); - fz->fz_hash = fz_hash_alloc(fz->fz_divisor); - if (!fz->fz_hash) { - kfree(fz); - return NULL; - } + fz->fz_divisor = z ? EMBEDDED_HASH_SIZE : 1; + fz->fz_hashmask = fz->fz_divisor - 1; + fz->fz_hash = fz->fz_embedded_hash; fz->fz_order = z; + fz->fz_revorder = 32 - z; fz->fz_mask = inet_make_mask(z); /* Find the first not empty zone with more specific mask */ |