diff options
| -rw-r--r-- | include/linux/rhashtable.h | 2 | ||||
| -rw-r--r-- | lib/rhashtable.c | 18 |
2 files changed, 8 insertions, 12 deletions
diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h index 73c913f..326acd8 100644 --- a/include/linux/rhashtable.h +++ b/include/linux/rhashtable.h @@ -113,7 +113,7 @@ struct rhashtable { struct bucket_table __rcu *tbl; struct bucket_table __rcu *future_tbl; atomic_t nelems; - size_t shift; + atomic_t shift; struct rhashtable_params p; struct delayed_work run_work; struct mutex mutex; diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 1aef942..7fb474b 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -199,7 +199,8 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht, bool rht_grow_above_75(const struct rhashtable *ht, size_t new_size) { /* Expand table when exceeding 75% load */ - return atomic_read(&ht->nelems) > (new_size / 4 * 3); + return atomic_read(&ht->nelems) > (new_size / 4 * 3) && + (ht->p.max_shift && atomic_read(&ht->shift) < ht->p.max_shift); } EXPORT_SYMBOL_GPL(rht_grow_above_75); @@ -211,7 +212,8 @@ EXPORT_SYMBOL_GPL(rht_grow_above_75); bool rht_shrink_below_30(const struct rhashtable *ht, size_t new_size) { /* Shrink table beneath 30% load */ - return atomic_read(&ht->nelems) < (new_size * 3 / 10); + return atomic_read(&ht->nelems) < (new_size * 3 / 10) && + (atomic_read(&ht->shift) > ht->p.min_shift); } EXPORT_SYMBOL_GPL(rht_shrink_below_30); @@ -318,14 +320,11 @@ int rhashtable_expand(struct rhashtable *ht) ASSERT_RHT_MUTEX(ht); - if (ht->p.max_shift && ht->shift >= ht->p.max_shift) - return 0; - new_tbl = bucket_table_alloc(ht, old_tbl->size * 2); if (new_tbl == NULL) return -ENOMEM; - ht->shift++; + atomic_inc(&ht->shift); /* Make insertions go into the new, empty table right away. Deletions * and lookups will be attempted in both tables until we synchronize. @@ -421,9 +420,6 @@ int rhashtable_shrink(struct rhashtable *ht) ASSERT_RHT_MUTEX(ht); - if (ht->shift <= ht->p.min_shift) - return 0; - new_tbl = bucket_table_alloc(ht, tbl->size / 2); if (new_tbl == NULL) return -ENOMEM; @@ -462,7 +458,7 @@ int rhashtable_shrink(struct rhashtable *ht) /* Publish the new, valid hash table */ rcu_assign_pointer(ht->tbl, new_tbl); - ht->shift--; + atomic_dec(&ht->shift); /* Wait for readers. No new readers will have references to the * old hash table. @@ -851,7 +847,7 @@ int rhashtable_init(struct rhashtable *ht, struct rhashtable_params *params) if (tbl == NULL) return -ENOMEM; - ht->shift = ilog2(tbl->size); + atomic_set(&ht->shift, ilog2(tbl->size)); RCU_INIT_POINTER(ht->tbl, tbl); RCU_INIT_POINTER(ht->future_tbl, tbl); |