Commit 7cd10db8 authored by Thomas Graf's avatar Thomas Graf Committed by David S. Miller
Browse files

rhashtable: Add more lock verification 



Catch hash miscalculations which result in hard to track down race
conditions.

Signed-off-by: default avatarThomas Graf <tgraf@suug.ch>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a03eaec0

lib/rhashtable.c

+8 −2
Original line number Diff line number Diff line
@@ -348,9 +348,11 @@ static bool hashtable_chain_unzip(struct rhashtable *ht, 
	return !rht_is_a_nulls(p);

}



static void link_old_to_new(struct bucket_table *new_tbl,

static void link_old_to_new(struct rhashtable *ht, struct bucket_table *new_tbl,

			    unsigned int new_hash, struct rhash_head *entry)

{

	ASSERT_BUCKET_LOCK(ht, new_tbl, new_hash);



	rcu_assign_pointer(*bucket_tail(new_tbl, new_hash), entry);

}
@@ -406,7 +408,7 @@ int rhashtable_expand(struct rhashtable *ht) 
		lock_buckets(new_tbl, old_tbl, new_hash);

		rht_for_each(he, old_tbl, old_hash) {

			if (head_hashfn(ht, new_tbl, he) == new_hash) {

				link_old_to_new(new_tbl, new_hash, he);

				link_old_to_new(ht, new_tbl, new_hash, he);

				break;

			}

		}
@@ -492,6 +494,7 @@ int rhashtable_shrink(struct rhashtable *ht) 


		rcu_assign_pointer(*bucket_tail(new_tbl, new_hash),

				   tbl->buckets[new_hash]);

		ASSERT_BUCKET_LOCK(ht, tbl, new_hash + new_tbl->size);

		rcu_assign_pointer(*bucket_tail(new_tbl, new_hash),

				   tbl->buckets[new_hash + new_tbl->size]);
@@ -557,6 +560,8 @@ static void __rhashtable_insert(struct rhashtable *ht, struct rhash_head *obj, 
	struct rhash_head *head = rht_dereference_bucket(tbl->buckets[hash],

							 tbl, hash);



	ASSERT_BUCKET_LOCK(ht, tbl, hash);



	if (rht_is_a_nulls(head))

		INIT_RHT_NULLS_HEAD(obj->next, ht, hash);

	else
@@ -641,6 +646,7 @@ bool rhashtable_remove(struct rhashtable *ht, struct rhash_head *obj) 
			continue;

		}



		ASSERT_BUCKET_LOCK(ht, tbl, hash);

		rcu_assign_pointer(*pprev, obj->next);



		ret = true;