1 files changed, 31 insertions, 35 deletions

diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 7a940d92f17e..06c28728bb53 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -30,7 +30,7 @@
 
 #define HASH_DEFAULT_SIZE	64UL
 #define HASH_MIN_SIZE		4U
-#define BUCKET_LOCKS_PER_CPU   128UL
+#define BUCKET_LOCKS_PER_CPU	32UL
 
 static u32 head_hashfn(struct rhashtable *ht,
 		       const struct bucket_table *tbl,
@@ -70,21 +70,25 @@ static int alloc_bucket_locks(struct rhashtable *ht, struct bucket_table *tbl,
 	unsigned int nr_pcpus = num_possible_cpus();
 #endif
 
-	nr_pcpus = min_t(unsigned int, nr_pcpus, 32UL);
+	nr_pcpus = min_t(unsigned int, nr_pcpus, 64UL);
 	size = roundup_pow_of_two(nr_pcpus * ht->p.locks_mul);
 
 	/* Never allocate more than 0.5 locks per bucket */
 	size = min_t(unsigned int, size, tbl->size >> 1);
 
 	if (sizeof(spinlock_t) != 0) {
+		tbl->locks = NULL;
 #ifdef CONFIG_NUMA
 		if (size * sizeof(spinlock_t) > PAGE_SIZE &&
 		    gfp == GFP_KERNEL)
 			tbl->locks = vmalloc(size * sizeof(spinlock_t));
-		else
 #endif
-		tbl->locks = kmalloc_array(size, sizeof(spinlock_t),
-					   gfp);
+		if (gfp != GFP_KERNEL)
+			gfp |= __GFP_NOWARN | __GFP_NORETRY;
+
+		if (!tbl->locks)
+			tbl->locks = kmalloc_array(size, sizeof(spinlock_t),
+						   gfp);
 		if (!tbl->locks)
 			return -ENOMEM;
 		for (i = 0; i < size; i++)
@@ -321,12 +325,14 @@ static int rhashtable_expand(struct rhashtable *ht)
 static int rhashtable_shrink(struct rhashtable *ht)
 {
 	struct bucket_table *new_tbl, *old_tbl = rht_dereference(ht->tbl, ht);
-	unsigned int size;
+	unsigned int nelems = atomic_read(&ht->nelems);
+	unsigned int size = 0;
 	int err;
 
 	ASSERT_RHT_MUTEX(ht);
 
-	size = roundup_pow_of_two(atomic_read(&ht->nelems) * 3 / 2);
+	if (nelems)
+		size = roundup_pow_of_two(nelems * 3 / 2);
 	if (size < ht->p.min_size)
 		size = ht->p.min_size;
 
@@ -488,10 +494,9 @@ exit:
 EXPORT_SYMBOL_GPL(rhashtable_insert_slow);
 
 /**
- * rhashtable_walk_init - Initialise an iterator
+ * rhashtable_walk_enter - Initialise an iterator
  * @ht:		Table to walk over
  * @iter:	Hash table Iterator
- * @gfp:	GFP flags for allocations
  *
  * This function prepares a hash table walk.
  *
@@ -506,30 +511,22 @@ EXPORT_SYMBOL_GPL(rhashtable_insert_slow);
  * This function may sleep so you must not call it from interrupt
  * context or with spin locks held.
  *
- * You must call rhashtable_walk_exit if this function returns
- * successfully.
+ * You must call rhashtable_walk_exit after this function returns.
  */
-int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter,
-			 gfp_t gfp)
+void rhashtable_walk_enter(struct rhashtable *ht, struct rhashtable_iter *iter)
 {
 	iter->ht = ht;
 	iter->p = NULL;
 	iter->slot = 0;
 	iter->skip = 0;
 
-	iter->walker = kmalloc(sizeof(*iter->walker), gfp);
-	if (!iter->walker)
-		return -ENOMEM;
-
 	spin_lock(&ht->lock);
-	iter->walker->tbl =
+	iter->walker.tbl =
 		rcu_dereference_protected(ht->tbl, lockdep_is_held(&ht->lock));
-	list_add(&iter->walker->list, &iter->walker->tbl->walkers);
+	list_add(&iter->walker.list, &iter->walker.tbl->walkers);
 	spin_unlock(&ht->lock);
-
-	return 0;
 }
-EXPORT_SYMBOL_GPL(rhashtable_walk_init);
+EXPORT_SYMBOL_GPL(rhashtable_walk_enter);
 
 /**
  * rhashtable_walk_exit - Free an iterator
@@ -540,10 +537,9 @@ EXPORT_SYMBOL_GPL(rhashtable_walk_init);
 void rhashtable_walk_exit(struct rhashtable_iter *iter)
 {
 	spin_lock(&iter->ht->lock);
-	if (iter->walker->tbl)
-		list_del(&iter->walker->list);
+	if (iter->walker.tbl)
+		list_del(&iter->walker.list);
 	spin_unlock(&iter->ht->lock);
-	kfree(iter->walker);
 }
 EXPORT_SYMBOL_GPL(rhashtable_walk_exit);
 
@@ -569,12 +565,12 @@ int rhashtable_walk_start(struct rhashtable_iter *iter)
 	rcu_read_lock();
 
 	spin_lock(&ht->lock);
-	if (iter->walker->tbl)
-		list_del(&iter->walker->list);
+	if (iter->walker.tbl)
+		list_del(&iter->walker.list);
 	spin_unlock(&ht->lock);
 
-	if (!iter->walker->tbl) {
-		iter->walker->tbl = rht_dereference_rcu(ht->tbl, ht);
+	if (!iter->walker.tbl) {
+		iter->walker.tbl = rht_dereference_rcu(ht->tbl, ht);
 		return -EAGAIN;
 	}
 
@@ -596,7 +592,7 @@ EXPORT_SYMBOL_GPL(rhashtable_walk_start);
  */
 void *rhashtable_walk_next(struct rhashtable_iter *iter)
 {
-	struct bucket_table *tbl = iter->walker->tbl;
+	struct bucket_table *tbl = iter->walker.tbl;
 	struct rhashtable *ht = iter->ht;
 	struct rhash_head *p = iter->p;
 
@@ -629,8 +625,8 @@ next:
 	/* Ensure we see any new tables. */
 	smp_rmb();
 
-	iter->walker->tbl = rht_dereference_rcu(tbl->future_tbl, ht);
-	if (iter->walker->tbl) {
+	iter->walker.tbl = rht_dereference_rcu(tbl->future_tbl, ht);
+	if (iter->walker.tbl) {
 		iter->slot = 0;
 		iter->skip = 0;
 		return ERR_PTR(-EAGAIN);
@@ -650,7 +646,7 @@ void rhashtable_walk_stop(struct rhashtable_iter *iter)
 	__releases(RCU)
 {
 	struct rhashtable *ht;
-	struct bucket_table *tbl = iter->walker->tbl;
+	struct bucket_table *tbl = iter->walker.tbl;
 
 	if (!tbl)
 		goto out;
@@ -659,9 +655,9 @@ void rhashtable_walk_stop(struct rhashtable_iter *iter)
 
 	spin_lock(&ht->lock);
 	if (tbl->rehash < tbl->size)
-		list_add(&iter->walker->list, &tbl->walkers);
+		list_add(&iter->walker.list, &tbl->walkers);
 	else
-		iter->walker->tbl = NULL;
+		iter->walker.tbl = NULL;
 	spin_unlock(&ht->lock);
 
 	iter->p = NULL;