lib/rhashtable: consider param->min_size when setting initial table size
authorDavidlohr Bueso <dave@stgolabs.net>
Mon, 16 Jul 2018 20:26:13 +0000 (13:26 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 25 Jul 2018 09:25:09 +0000 (11:25 +0200)
[ Upstream commit 107d01f5ba10f4162c38109496607eb197059064 ]

rhashtable_init() currently does not take into account the user-passed
min_size parameter unless param->nelem_hint is set as well. As such,
the default size (number of buckets) will always be HASH_DEFAULT_SIZE
even if the smallest allowed size is larger than that. Remediate this
by unconditionally calling into rounded_hashtable_size() and handling
things accordingly.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
lib/rhashtable.c

index b734ce7..39215c7 100644 (file)
@@ -878,8 +878,16 @@ EXPORT_SYMBOL_GPL(rhashtable_walk_stop);
 
 static size_t rounded_hashtable_size(const struct rhashtable_params *params)
 {
-       return max(roundup_pow_of_two(params->nelem_hint * 4 / 3),
-                  (unsigned long)params->min_size);
+       size_t retsize;
+
+       if (params->nelem_hint)
+               retsize = max(roundup_pow_of_two(params->nelem_hint * 4 / 3),
+                             (unsigned long)params->min_size);
+       else
+               retsize = max(HASH_DEFAULT_SIZE,
+                             (unsigned long)params->min_size);
+
+       return retsize;
 }
 
 static u32 rhashtable_jhash2(const void *key, u32 length, u32 seed)
@@ -936,8 +944,6 @@ int rhashtable_init(struct rhashtable *ht,
        struct bucket_table *tbl;
        size_t size;
 
-       size = HASH_DEFAULT_SIZE;
-
        if ((!params->key_len && !params->obj_hashfn) ||
            (params->obj_hashfn && !params->obj_cmpfn))
                return -EINVAL;
@@ -964,8 +970,7 @@ int rhashtable_init(struct rhashtable *ht,
 
        ht->p.min_size = max_t(u16, ht->p.min_size, HASH_MIN_SIZE);
 
-       if (params->nelem_hint)
-               size = rounded_hashtable_size(&ht->p);
+       size = rounded_hashtable_size(&ht->p);
 
        if (params->locks_mul)
                ht->p.locks_mul = roundup_pow_of_two(params->locks_mul);