rhashtable: Add rehash counter to bucket_table

This patch adds a rehash counter to bucket_table to indicate
the last bucket that has been rehashed.  This serves two purposes:

1. Any bucket that has been rehashed can never gain a new object.
2. If the rehash counter reaches the size of the table, the table
will forever remain empty.

This patch also downsizes bucket_table->size to an unsigned int
since we do not support sizes greater than 32 bits yet.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 2 insertions, 1 deletions

diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 36fb0910bec2..ff4ea1704546 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -260,6 +260,7 @@ static void rhashtable_rehash_chain(struct rhashtable *ht, unsigned old_hash)
         spin_lock_bh(old_bucket_lock);
         while (!rhashtable_rehash_one(ht, old_hash))
                 ;
+        old_tbl->rehash++;
         spin_unlock_bh(old_bucket_lock);
 }
 
diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c
index 67c7593d1dd6..16974fd89e4e 100644
--- a/lib/test_rhashtable.c
+++ b/lib/test_rhashtable.c
@@ -80,7 +80,7 @@ static void test_bucket_stats(struct rhashtable *ht, bool quiet)
                 rcu_cnt = cnt = 0;
 
                 if (!quiet)
-                        pr_info(" [%#4x/%zu]", i, tbl->size);
+                        pr_info(" [%#4x/%u]", i, tbl->size);
 
                 rht_for_each_entry_rcu(obj, pos, tbl, i, node) {
                         cnt++;