commit 83e7e4ce9e93c3 ("mac80211: Use rhltable instead of rhashtable")
removed the last user that made use of 'insecure_elasticity' parameter,
i.e. the default of 16 is used everywhere.
Replace it with a constant.
Signed-off-by: Florian Westphal <f...@strlen.de>
---
include/linux/rhashtable.h | 21 ++++++++++++++++-----
lib/rhashtable.c | 17 +----------------
2 files changed, 17 insertions(+), 21 deletions(-)
diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h
index e507290cd2c7..ae87dcdf52d2 100644
--- a/include/linux/rhashtable.h
+++ b/include/linux/rhashtable.h
@@ -49,6 +49,21 @@
/* Base bits plus 1 bit for nulls marker */
#define RHT_HASH_RESERVED_SPACE (RHT_BASE_BITS + 1)
+/* Maximum chain length before rehash
+ *
+ * The maximum (not average) chain length grows with the size of the hash
+ * table, at a rate of (log N)/(log log N).
+ *
+ * The value of 16 is selected so that even if the hash table grew to
+ * 2^32 you would not expect the maximum chain length to exceed it
+ * unless we are under attack (or extremely unlucky).
+ *
+ * As this limit is only to detect attacks, we don't need to set it to a
+ * lower value as you'd need the chain length to vastly exceed 16 to have
+ * any real effect on the system.
+ */
+#define RHT_ELASTICITY 16u
+
struct rhash_head {
struct rhash_head __rcu *next;
};
@@ -114,7 +129,6 @@ struct rhashtable;
* @max_size: Maximum size while expanding
* @min_size: Minimum size while shrinking
* @nulls_base: Base value to generate nulls marker
- * @insecure_elasticity: Set to true to disable chain length checks
* @automatic_shrinking: Enable automatic shrinking of tables
* @locks_mul: Number of bucket locks to allocate per cpu (default: 128)
* @hashfn: Hash function (default: jhash2 if !(key_len % 4), or jhash)
@@ -130,7 +144,6 @@ struct rhashtable_params {
unsigned int max_size;
unsigned int min_size;
u32 nulls_base;
- bool insecure_elasticity;
bool automatic_shrinking;
size_t locks_mul;
rht_hashfn_t hashfn;
@@ -143,7 +156,6 @@ struct rhashtable_params {
* @tbl: Bucket table
* @nelems: Number of elements in table
* @key_len: Key length for hashfn
- * @elasticity: Maximum chain length before rehash
* @p: Configuration parameters
* @rhlist: True if this is an rhltable
* @run_work: Deferred worker to expand/shrink asynchronously
@@ -154,7 +166,6 @@ struct rhashtable {
struct bucket_table __rcu *tbl;
atomic_t nelems;
unsigned int key_len;
- unsigned int elasticity;
struct rhashtable_params p;
bool rhlist;
struct work_struct run_work;
@@ -726,7 +737,7 @@ static inline void *__rhashtable_insert_fast(
return rhashtable_insert_slow(ht, key, obj);
}
- elasticity = ht->elasticity;
+ elasticity = RHT_ELASTICITY;
pprev = rht_bucket_insert(ht, tbl, hash);
data = ERR_PTR(-ENOMEM);
if (!pprev)
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index f8635fd57442..d22a5ef109fb 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -535,7 +535,7 @@ static void *rhashtable_lookup_one(struct rhashtable *ht,
struct rhash_head *head;
int elasticity;
- elasticity = ht->elasticity;
+ elasticity = RHT_ELASTICITY;
pprev = rht_bucket_var(tbl, hash);
rht_for_each_continue(head, *pprev, tbl, hash) {
struct rhlist_head *list;
@@ -972,21 +972,6 @@ int rhashtable_init(struct rhashtable *ht,
if (params->nelem_hint)
size = rounded_hashtable_size(&ht->p);
- /* The maximum (not average) chain length grows with the
- * size of the hash table, at a rate of (log N)/(log log N).
- * The value of 16 is selected so that even if the hash
- * table grew to 2^32 you would not expect the maximum
- * chain length to exceed it unless we are under attack
- * (or extremely unlucky).
- *
- * As this limit is only to detect attacks, we don't need
- * to set it to a lower value as you'd need the chain
- * length to vastly exceed 16 to have any real effect
- * on the system.
- */
- if (!params->insecure_elasticity)
- ht->elasticity = 16;
-
if (params->locks_mul)
ht->p.locks_mul = roundup_pow_of_two(params->locks_mul);
else
--
2.10.2
