diff options
| -rw-r--r-- | include/linux/rhashtable.h | 4 | ||||
| -rw-r--r-- | lib/rhashtable.c | 12 |
2 files changed, 12 insertions, 4 deletions
diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h index f16e85692959..81267fef85d7 100644 --- a/include/linux/rhashtable.h +++ b/include/linux/rhashtable.h @@ -85,6 +85,8 @@ struct rhashtable; * @head_offset: Offset of rhash_head in struct to be hashed * @max_shift: Maximum number of shifts while expanding * @min_shift: Minimum number of shifts while shrinking + * @max_size: Maximum size while expanding + * @min_size: Minimum size while shrinking * @nulls_base: Base value to generate nulls marker * @locks_mul: Number of bucket locks to allocate per cpu (default: 128) * @hashfn: Function to hash key @@ -97,6 +99,8 @@ struct rhashtable_params { size_t head_offset; size_t max_shift; size_t min_shift; + unsigned int max_size; + unsigned int min_size; u32 nulls_base; size_t locks_mul; rht_hashfn_t hashfn; diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 097400362467..c4061bbd0113 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -27,7 +27,7 @@ #include <linux/err.h> #define HASH_DEFAULT_SIZE 64UL -#define HASH_MIN_SIZE 4UL +#define HASH_MIN_SIZE 4U #define BUCKET_LOCKS_PER_CPU 128UL /* Base bits plus 1 bit for nulls marker */ @@ -188,7 +188,8 @@ static bool rht_grow_above_75(const struct rhashtable *ht, { /* Expand table when exceeding 75% load */ return atomic_read(&ht->nelems) > (tbl->size / 4 * 3) && - (!ht->p.max_shift || tbl->size < (1 << ht->p.max_shift)); + (!ht->p.max_shift || tbl->size < (1 << ht->p.max_shift)) && + (!ht->p.max_size || tbl->size < ht->p.max_size); } /** @@ -201,7 +202,8 @@ static bool rht_shrink_below_30(const struct rhashtable *ht, { /* Shrink table beneath 30% load */ return atomic_read(&ht->nelems) < (tbl->size * 3 / 10) && - tbl->size > (1 << ht->p.min_shift); + tbl->size > (1 << ht->p.min_shift) && + tbl->size > ht->p.min_size; } static int rhashtable_rehash_one(struct rhashtable *ht, unsigned old_hash) @@ -873,7 +875,8 @@ EXPORT_SYMBOL_GPL(rhashtable_walk_stop); static size_t rounded_hashtable_size(struct rhashtable_params *params) { return max(roundup_pow_of_two(params->nelem_hint * 4 / 3), - 1UL << params->min_shift); + max(1UL << params->min_shift, + (unsigned long)params->min_size)); } /** @@ -935,6 +938,7 @@ int rhashtable_init(struct rhashtable *ht, struct rhashtable_params *params) params->min_shift = max_t(size_t, params->min_shift, ilog2(HASH_MIN_SIZE)); + params->min_size = max(params->min_size, HASH_MIN_SIZE); if (params->nelem_hint) size = rounded_hashtable_size(params); |