diff options
| -rw-r--r-- | lib/rhashtable.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/lib/rhashtable.c b/lib/rhashtable.c index bdb7e4cadf05..9f6890aedd1a 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -63,13 +63,22 @@ EXPORT_SYMBOL_GPL(lockdep_rht_bucket_is_held); #define ASSERT_RHT_MUTEX(HT) #endif +static inline union nested_table *nested_table_top( + const struct bucket_table *tbl) +{ + /* The top-level bucket entry does not need RCU protection + * because it's set at the same time as tbl->nest. + */ + return (void *)rcu_dereference_protected(tbl->buckets[0], 1); +} + static void nested_table_free(union nested_table *ntbl, unsigned int size) { const unsigned int shift = PAGE_SHIFT - ilog2(sizeof(void *)); const unsigned int len = 1 << shift; unsigned int i; - ntbl = rcu_dereference_raw(ntbl->table); + ntbl = rcu_dereference_protected(ntbl->table, 1); if (!ntbl) return; @@ -89,7 +98,7 @@ static void nested_bucket_table_free(const struct bucket_table *tbl) union nested_table *ntbl; unsigned int i; - ntbl = (union nested_table *)rcu_dereference_raw(tbl->buckets[0]); + ntbl = nested_table_top(tbl); for (i = 0; i < len; i++) nested_table_free(ntbl + i, size); @@ -1173,7 +1182,7 @@ struct rhash_lock_head **__rht_bucket_nested(const struct bucket_table *tbl, unsigned int subhash = hash; union nested_table *ntbl; - ntbl = (union nested_table *)rcu_dereference_raw(tbl->buckets[0]); + ntbl = nested_table_top(tbl); ntbl = rht_dereference_bucket_rcu(ntbl[index].table, tbl, hash); subhash >>= tbl->nest; @@ -1213,7 +1222,7 @@ struct rhash_lock_head **rht_bucket_nested_insert(struct rhashtable *ht, unsigned int size = tbl->size >> tbl->nest; union nested_table *ntbl; - ntbl = (union nested_table *)rcu_dereference_raw(tbl->buckets[0]); + ntbl = nested_table_top(tbl); hash >>= tbl->nest; ntbl = nested_table_alloc(ht, &ntbl[index].table, size <= (1 << shift)); |