diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h
index f624d4b..a1688f0 100644
--- a/include/linux/rhashtable.h
+++ b/include/linux/rhashtable.h
@@ -19,6 +19,7 @@
 #define _LINUX_RHASHTABLE_H
 
 #include <linux/rculist.h>
+#include <linux/workqueue.h>
 
 struct rhash_head {
 	struct rhash_head __rcu		*next;
@@ -26,8 +27,17 @@
 
 #define INIT_HASH_HEAD(ptr) ((ptr)->next = NULL)
 
+/**
+ * struct bucket_table - Table of hash buckets
+ * @size: Number of hash buckets
+ * @locks_mask: Mask to apply before accessing locks[]
+ * @locks: Array of spinlocks protecting individual buckets
+ * @buckets: size * hash buckets
+ */
 struct bucket_table {
 	size_t				size;
+	unsigned int			locks_mask;
+	spinlock_t			*locks;
 	struct rhash_head __rcu		*buckets[];
 };
 
@@ -45,11 +55,11 @@
  * @hash_rnd: Seed to use while hashing
  * @max_shift: Maximum number of shifts while expanding
  * @min_shift: Minimum number of shifts while shrinking
+ * @locks_mul: Number of bucket locks to allocate per cpu (default: 128)
  * @hashfn: Function to hash key
  * @obj_hashfn: Function to hash object
  * @grow_decision: If defined, may return true if table should expand
  * @shrink_decision: If defined, may return true if table should shrink
- * @mutex_is_held: Must return true if protecting mutex is held
  */
 struct rhashtable_params {
 	size_t			nelem_hint;
@@ -59,37 +69,42 @@
 	u32			hash_rnd;
 	size_t			max_shift;
 	size_t			min_shift;
+	size_t			locks_mul;
 	rht_hashfn_t		hashfn;
 	rht_obj_hashfn_t	obj_hashfn;
 	bool			(*grow_decision)(const struct rhashtable *ht,
 						 size_t new_size);
 	bool			(*shrink_decision)(const struct rhashtable *ht,
 						   size_t new_size);
-#ifdef CONFIG_PROVE_LOCKING
-	int			(*mutex_is_held)(void *parent);
-	void			*parent;
-#endif
 };
 
 /**
  * struct rhashtable - Hash table handle
  * @tbl: Bucket table
+ * @future_tbl: Table under construction during expansion/shrinking
  * @nelems: Number of elements in table
  * @shift: Current size (1 << shift)
  * @p: Configuration parameters
+ * @run_work: Deferred worker to expand/shrink asynchronously
+ * @mutex: Mutex to protect current/future table swapping
+ * @being_destroyed: True if table is set up for destruction
  */
 struct rhashtable {
 	struct bucket_table __rcu	*tbl;
-	size_t				nelems;
+	struct bucket_table __rcu       *future_tbl;
+	atomic_t			nelems;
 	size_t				shift;
 	struct rhashtable_params	p;
+	struct delayed_work             run_work;
+	struct mutex                    mutex;
+	bool                            being_destroyed;
 };
 
 #ifdef CONFIG_PROVE_LOCKING
-int lockdep_rht_mutex_is_held(const struct rhashtable *ht);
+int lockdep_rht_mutex_is_held(struct rhashtable *ht);
 int lockdep_rht_bucket_is_held(const struct bucket_table *tbl, u32 hash);
 #else
-static inline int lockdep_rht_mutex_is_held(const struct rhashtable *ht)
+static inline int lockdep_rht_mutex_is_held(struct rhashtable *ht)
 {
 	return 1;
 }
@@ -112,11 +127,11 @@
 int rhashtable_expand(struct rhashtable *ht);
 int rhashtable_shrink(struct rhashtable *ht);
 
-void *rhashtable_lookup(const struct rhashtable *ht, const void *key);
-void *rhashtable_lookup_compare(const struct rhashtable *ht, const void *key,
+void *rhashtable_lookup(struct rhashtable *ht, const void *key);
+void *rhashtable_lookup_compare(struct rhashtable *ht, const void *key,
 				bool (*compare)(void *, void *), void *arg);
 
-void rhashtable_destroy(const struct rhashtable *ht);
+void rhashtable_destroy(struct rhashtable *ht);
 
 #define rht_dereference(p, ht) \
 	rcu_dereference_protected(p, lockdep_rht_mutex_is_held(ht))
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index e6b85c4..312e343 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -26,19 +26,42 @@
 
 #define HASH_DEFAULT_SIZE	64UL
 #define HASH_MIN_SIZE		4UL
+#define BUCKET_LOCKS_PER_CPU   128UL
+
+enum {
+	RHT_LOCK_NORMAL,
+	RHT_LOCK_NESTED,
+	RHT_LOCK_NESTED2,
+};
+
+/* The bucket lock is selected based on the hash and protects mutations
+ * on a group of hash buckets.
+ *
+ * IMPORTANT: When holding the bucket lock of both the old and new table
+ * during expansions and shrinking, the old bucket lock must always be
+ * acquired first.
+ */
+static spinlock_t *bucket_lock(const struct bucket_table *tbl, u32 hash)
+{
+	return &tbl->locks[hash & tbl->locks_mask];
+}
 
 #define ASSERT_RHT_MUTEX(HT) BUG_ON(!lockdep_rht_mutex_is_held(HT))
+#define ASSERT_BUCKET_LOCK(TBL, HASH) \
+	BUG_ON(!lockdep_rht_bucket_is_held(TBL, HASH))
 
 #ifdef CONFIG_PROVE_LOCKING
-int lockdep_rht_mutex_is_held(const struct rhashtable *ht)
+int lockdep_rht_mutex_is_held(struct rhashtable *ht)
 {
-	return ht->p.mutex_is_held(ht->p.parent);
+	return (debug_locks) ? lockdep_is_held(&ht->mutex) : 1;
 }
 EXPORT_SYMBOL_GPL(lockdep_rht_mutex_is_held);
 
 int lockdep_rht_bucket_is_held(const struct bucket_table *tbl, u32 hash)
 {
-	return 1;
+	spinlock_t *lock = bucket_lock(tbl, hash);
+
+	return (debug_locks) ? lockdep_is_held(lock) : 1;
 }
 EXPORT_SYMBOL_GPL(lockdep_rht_bucket_is_held);
 #endif
@@ -66,7 +89,7 @@
 	return hash;
 }
 
-static u32 key_hashfn(const struct rhashtable *ht, const void *key, u32 len)
+static u32 key_hashfn(struct rhashtable *ht, const void *key, u32 len)
 {
 	struct bucket_table *tbl = rht_dereference_rcu(ht->tbl, ht);
 	u32 hash;
@@ -95,7 +118,49 @@
 	return pprev;
 }
 
-static struct bucket_table *bucket_table_alloc(size_t nbuckets)
+static int alloc_bucket_locks(struct rhashtable *ht, struct bucket_table *tbl)
+{
+	unsigned int i, size;
+#if defined(CONFIG_PROVE_LOCKING)
+	unsigned int nr_pcpus = 2;
+#else
+	unsigned int nr_pcpus = num_possible_cpus();
+#endif
+
+	nr_pcpus = min_t(unsigned int, nr_pcpus, 32UL);
+	size = roundup_pow_of_two(nr_pcpus * ht->p.locks_mul);
+
+	/* Never allocate more than one lock per bucket */
+	size = min_t(unsigned int, size, tbl->size);
+
+	if (sizeof(spinlock_t) != 0) {
+#ifdef CONFIG_NUMA
+		if (size * sizeof(spinlock_t) > PAGE_SIZE)
+			tbl->locks = vmalloc(size * sizeof(spinlock_t));
+		else
+#endif
+		tbl->locks = kmalloc_array(size, sizeof(spinlock_t),
+					   GFP_KERNEL);
+		if (!tbl->locks)
+			return -ENOMEM;
+		for (i = 0; i < size; i++)
+			spin_lock_init(&tbl->locks[i]);
+	}
+	tbl->locks_mask = size - 1;
+
+	return 0;
+}
+
+static void bucket_table_free(const struct bucket_table *tbl)
+{
+	if (tbl)
+		kvfree(tbl->locks);
+
+	kvfree(tbl);
+}
+
+static struct bucket_table *bucket_table_alloc(struct rhashtable *ht,
+					       size_t nbuckets)
 {
 	struct bucket_table *tbl;
 	size_t size;
@@ -110,12 +175,12 @@
 
 	tbl->size = nbuckets;
 
-	return tbl;
-}
+	if (alloc_bucket_locks(ht, tbl) < 0) {
+		bucket_table_free(tbl);
+		return NULL;
+	}
 
-static void bucket_table_free(const struct bucket_table *tbl)
-{
-	kvfree(tbl);
+	return tbl;
 }
 
 /**
@@ -126,7 +191,7 @@
 bool rht_grow_above_75(const struct rhashtable *ht, size_t new_size)
 {
 	/* Expand table when exceeding 75% load */
-	return ht->nelems > (new_size / 4 * 3);
+	return atomic_read(&ht->nelems) > (new_size / 4 * 3);
 }
 EXPORT_SYMBOL_GPL(rht_grow_above_75);
 
@@ -138,41 +203,59 @@
 bool rht_shrink_below_30(const struct rhashtable *ht, size_t new_size)
 {
 	/* Shrink table beneath 30% load */
-	return ht->nelems < (new_size * 3 / 10);
+	return atomic_read(&ht->nelems) < (new_size * 3 / 10);
 }
 EXPORT_SYMBOL_GPL(rht_shrink_below_30);
 
 static void hashtable_chain_unzip(const struct rhashtable *ht,
 				  const struct bucket_table *new_tbl,
-				  struct bucket_table *old_tbl, size_t n)
+				  struct bucket_table *old_tbl,
+				  size_t old_hash)
 {
 	struct rhash_head *he, *p, *next;
-	unsigned int h;
+	spinlock_t *new_bucket_lock, *new_bucket_lock2 = NULL;
+	unsigned int new_hash, new_hash2;
+
+	ASSERT_BUCKET_LOCK(old_tbl, old_hash);
 
 	/* Old bucket empty, no work needed. */
-	p = rht_dereference(old_tbl->buckets[n], ht);
+	p = rht_dereference_bucket(old_tbl->buckets[old_hash], old_tbl,
+				   old_hash);
 	if (!p)
 		return;
 
+	new_hash = new_hash2 = head_hashfn(ht, new_tbl, p);
+	new_bucket_lock = bucket_lock(new_tbl, new_hash);
+
 	/* Advance the old bucket pointer one or more times until it
 	 * reaches a node that doesn't hash to the same bucket as the
 	 * previous node p. Call the previous node p;
 	 */
-	h = head_hashfn(ht, new_tbl, p);
-	rht_for_each_continue(he, p->next, old_tbl, n) {
-		if (head_hashfn(ht, new_tbl, he) != h)
+	rht_for_each_continue(he, p->next, old_tbl, old_hash) {
+		new_hash2 = head_hashfn(ht, new_tbl, he);
+		if (new_hash != new_hash2)
 			break;
 		p = he;
 	}
-	RCU_INIT_POINTER(old_tbl->buckets[n], p->next);
+	rcu_assign_pointer(old_tbl->buckets[old_hash], p->next);
+
+	spin_lock_bh_nested(new_bucket_lock, RHT_LOCK_NESTED);
+
+	/* If we have encountered an entry that maps to a different bucket in
+	 * the new table, lock down that bucket as well as we might cut off
+	 * the end of the chain.
+	 */
+	new_bucket_lock2 = bucket_lock(new_tbl, new_hash);
+	if (new_bucket_lock != new_bucket_lock2)
+		spin_lock_bh_nested(new_bucket_lock2, RHT_LOCK_NESTED2);
 
 	/* Find the subsequent node which does hash to the same
 	 * bucket as node P, or NULL if no such node exists.
 	 */
 	next = NULL;
 	if (he) {
-		rht_for_each_continue(he, he->next, old_tbl, n) {
-			if (head_hashfn(ht, new_tbl, he) == h) {
+		rht_for_each_continue(he, he->next, old_tbl, old_hash) {
+			if (head_hashfn(ht, new_tbl, he) == new_hash) {
 				next = he;
 				break;
 			}
@@ -182,7 +265,23 @@
 	/* Set p's next pointer to that subsequent node pointer,
 	 * bypassing the nodes which do not hash to p's bucket
 	 */
-	RCU_INIT_POINTER(p->next, next);
+	rcu_assign_pointer(p->next, next);
+
+	if (new_bucket_lock != new_bucket_lock2)
+		spin_unlock_bh(new_bucket_lock2);
+	spin_unlock_bh(new_bucket_lock);
+}
+
+static void link_old_to_new(struct bucket_table *new_tbl,
+			    unsigned int new_hash, struct rhash_head *entry)
+{
+	spinlock_t *new_bucket_lock;
+
+	new_bucket_lock = bucket_lock(new_tbl, new_hash);
+
+	spin_lock_bh_nested(new_bucket_lock, RHT_LOCK_NESTED);
+	rcu_assign_pointer(*bucket_tail(new_tbl, new_hash), entry);
+	spin_unlock_bh(new_bucket_lock);
 }
 
 /**
@@ -195,43 +294,59 @@
  * This function may only be called in a context where it is safe to call
  * synchronize_rcu(), e.g. not within a rcu_read_lock() section.
  *
- * The caller must ensure that no concurrent table mutations take place.
- * It is however valid to have concurrent lookups if they are RCU protected.
+ * The caller must ensure that no concurrent resizing occurs by holding
+ * ht->mutex.
+ *
+ * It is valid to have concurrent insertions and deletions protected by per
+ * bucket locks or concurrent RCU protected lookups and traversals.
  */
 int rhashtable_expand(struct rhashtable *ht)
 {
 	struct bucket_table *new_tbl, *old_tbl = rht_dereference(ht->tbl, ht);
 	struct rhash_head *he;
-	unsigned int i, h;
-	bool complete;
+	spinlock_t *old_bucket_lock;
+	unsigned int new_hash, old_hash;
+	bool complete = false;
 
 	ASSERT_RHT_MUTEX(ht);
 
 	if (ht->p.max_shift && ht->shift >= ht->p.max_shift)
 		return 0;
 
-	new_tbl = bucket_table_alloc(old_tbl->size * 2);
+	new_tbl = bucket_table_alloc(ht, old_tbl->size * 2);
 	if (new_tbl == NULL)
 		return -ENOMEM;
 
 	ht->shift++;
 
-	/* For each new bucket, search the corresponding old bucket
-	 * for the first entry that hashes to the new bucket, and
-	 * link the new bucket to that entry. Since all the entries
-	 * which will end up in the new bucket appear in the same
-	 * old bucket, this constructs an entirely valid new hash
-	 * table, but with multiple buckets "zipped" together into a
-	 * single imprecise chain.
+	/* Make insertions go into the new, empty table right away. Deletions
+	 * and lookups will be attempted in both tables until we synchronize.
+	 * The synchronize_rcu() guarantees for the new table to be picked up
+	 * so no new additions go into the old table while we relink.
 	 */
-	for (i = 0; i < new_tbl->size; i++) {
-		h = rht_bucket_index(old_tbl, i);
-		rht_for_each(he, old_tbl, h) {
-			if (head_hashfn(ht, new_tbl, he) == i) {
-				RCU_INIT_POINTER(new_tbl->buckets[i], he);
+	rcu_assign_pointer(ht->future_tbl, new_tbl);
+	synchronize_rcu();
+
+	/* For each new bucket, search the corresponding old bucket for the
+	 * first entry that hashes to the new bucket, and link the end of
+	 * newly formed bucket chain (containing entries added to future
+	 * table) to that entry. Since all the entries which will end up in
+	 * the new bucket appear in the same old bucket, this constructs an
+	 * entirely valid new hash table, but with multiple buckets
+	 * "zipped" together into a single imprecise chain.
+	 */
+	for (new_hash = 0; new_hash < new_tbl->size; new_hash++) {
+		old_hash = rht_bucket_index(old_tbl, new_hash);
+		old_bucket_lock = bucket_lock(old_tbl, old_hash);
+
+		spin_lock_bh(old_bucket_lock);
+		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);
 				break;
 			}
 		}
+		spin_unlock_bh(old_bucket_lock);
 	}
 
 	/* Publish the new table pointer. Lookups may now traverse
@@ -241,7 +356,7 @@
 	rcu_assign_pointer(ht->tbl, new_tbl);
 
 	/* Unzip interleaved hash chains */
-	do {
+	while (!complete && !ht->being_destroyed) {
 		/* Wait for readers. All new readers will see the new
 		 * table, and thus no references to the old table will
 		 * remain.
@@ -253,12 +368,17 @@
 		 * table): ...
 		 */
 		complete = true;
-		for (i = 0; i < old_tbl->size; i++) {
-			hashtable_chain_unzip(ht, new_tbl, old_tbl, i);
-			if (old_tbl->buckets[i] != NULL)
+		for (old_hash = 0; old_hash < old_tbl->size; old_hash++) {
+			old_bucket_lock = bucket_lock(old_tbl, old_hash);
+			spin_lock_bh(old_bucket_lock);
+
+			hashtable_chain_unzip(ht, new_tbl, old_tbl, old_hash);
+			if (old_tbl->buckets[old_hash] != NULL)
 				complete = false;
+
+			spin_unlock_bh(old_bucket_lock);
 		}
-	} while (!complete);
+	}
 
 	bucket_table_free(old_tbl);
 	return 0;
@@ -272,38 +392,65 @@
  * This function may only be called in a context where it is safe to call
  * synchronize_rcu(), e.g. not within a rcu_read_lock() section.
  *
+ * The caller must ensure that no concurrent resizing occurs by holding
+ * ht->mutex.
+ *
  * The caller must ensure that no concurrent table mutations take place.
  * It is however valid to have concurrent lookups if they are RCU protected.
+ *
+ * It is valid to have concurrent insertions and deletions protected by per
+ * bucket locks or concurrent RCU protected lookups and traversals.
  */
 int rhashtable_shrink(struct rhashtable *ht)
 {
-	struct bucket_table *ntbl, *tbl = rht_dereference(ht->tbl, ht);
-	unsigned int i;
+	struct bucket_table *new_tbl, *tbl = rht_dereference(ht->tbl, ht);
+	spinlock_t *new_bucket_lock, *old_bucket_lock1, *old_bucket_lock2;
+	unsigned int new_hash;
 
 	ASSERT_RHT_MUTEX(ht);
 
 	if (ht->shift <= ht->p.min_shift)
 		return 0;
 
-	ntbl = bucket_table_alloc(tbl->size / 2);
-	if (ntbl == NULL)
+	new_tbl = bucket_table_alloc(ht, tbl->size / 2);
+	if (new_tbl == NULL)
 		return -ENOMEM;
 
-	ht->shift--;
+	rcu_assign_pointer(ht->future_tbl, new_tbl);
+	synchronize_rcu();
 
-	/* Link each bucket in the new table to the first bucket
-	 * in the old table that contains entries which will hash
-	 * to the new bucket.
+	/* Link the first entry in the old bucket to the end of the
+	 * bucket in the new table. As entries are concurrently being
+	 * added to the new table, lock down the new bucket. As we
+	 * always divide the size in half when shrinking, each bucket
+	 * in the new table maps to exactly two buckets in the old
+	 * table.
+	 *
+	 * As removals can occur concurrently on the old table, we need
+	 * to lock down both matching buckets in the old table.
 	 */
-	for (i = 0; i < ntbl->size; i++) {
-		ntbl->buckets[i] = tbl->buckets[i];
-		RCU_INIT_POINTER(*bucket_tail(ntbl, i),
-				 tbl->buckets[i + ntbl->size]);
+	for (new_hash = 0; new_hash < new_tbl->size; new_hash++) {
+		old_bucket_lock1 = bucket_lock(tbl, new_hash);
+		old_bucket_lock2 = bucket_lock(tbl, new_hash + new_tbl->size);
+		new_bucket_lock = bucket_lock(new_tbl, new_hash);
 
+		spin_lock_bh(old_bucket_lock1);
+		spin_lock_bh_nested(old_bucket_lock2, RHT_LOCK_NESTED);
+		spin_lock_bh_nested(new_bucket_lock, RHT_LOCK_NESTED2);
+
+		rcu_assign_pointer(*bucket_tail(new_tbl, new_hash),
+				   tbl->buckets[new_hash]);
+		rcu_assign_pointer(*bucket_tail(new_tbl, new_hash),
+				   tbl->buckets[new_hash + new_tbl->size]);
+
+		spin_unlock_bh(new_bucket_lock);
+		spin_unlock_bh(old_bucket_lock2);
+		spin_unlock_bh(old_bucket_lock1);
 	}
 
 	/* Publish the new, valid hash table */
-	rcu_assign_pointer(ht->tbl, ntbl);
+	rcu_assign_pointer(ht->tbl, new_tbl);
+	ht->shift--;
 
 	/* Wait for readers. No new readers will have references to the
 	 * old hash table.
@@ -316,31 +463,63 @@
 }
 EXPORT_SYMBOL_GPL(rhashtable_shrink);
 
+static void rht_deferred_worker(struct work_struct *work)
+{
+	struct rhashtable *ht;
+	struct bucket_table *tbl;
+
+	ht = container_of(work, struct rhashtable, run_work.work);
+	mutex_lock(&ht->mutex);
+	tbl = rht_dereference(ht->tbl, ht);
+
+	if (ht->p.grow_decision && ht->p.grow_decision(ht, tbl->size))
+		rhashtable_expand(ht);
+	else if (ht->p.shrink_decision && ht->p.shrink_decision(ht, tbl->size))
+		rhashtable_shrink(ht);
+
+	mutex_unlock(&ht->mutex);
+}
+
 /**
  * rhashtable_insert - insert object into hash hash table
  * @ht:		hash table
  * @obj:	pointer to hash head inside object
  *
- * Will automatically grow the table via rhashtable_expand() if the the
- * grow_decision function specified at rhashtable_init() returns true.
+ * Will take a per bucket spinlock to protect against mutual mutations
+ * on the same bucket. Multiple insertions may occur in parallel unless
+ * they map to the same bucket lock.
  *
- * The caller must ensure that no concurrent table mutations occur. It is
- * however valid to have concurrent lookups if they are RCU protected.
+ * It is safe to call this function from atomic context.
+ *
+ * Will trigger an automatic deferred table resizing if the size grows
+ * beyond the watermark indicated by grow_decision() which can be passed
+ * to rhashtable_init().
  */
 void rhashtable_insert(struct rhashtable *ht, struct rhash_head *obj)
 {
-	struct bucket_table *tbl = rht_dereference(ht->tbl, ht);
-	u32 hash;
+	struct bucket_table *tbl;
+	spinlock_t *lock;
+	unsigned hash;
 
-	ASSERT_RHT_MUTEX(ht);
+	rcu_read_lock();
 
+	tbl = rht_dereference_rcu(ht->future_tbl, ht);
 	hash = head_hashfn(ht, tbl, obj);
+	lock = bucket_lock(tbl, hash);
+
+	spin_lock_bh(lock);
 	RCU_INIT_POINTER(obj->next, tbl->buckets[hash]);
 	rcu_assign_pointer(tbl->buckets[hash], obj);
-	ht->nelems++;
+	spin_unlock_bh(lock);
 
-	if (ht->p.grow_decision && ht->p.grow_decision(ht, tbl->size))
-		rhashtable_expand(ht);
+	atomic_inc(&ht->nelems);
+
+	/* Only grow the table if no resizing is currently in progress. */
+	if (ht->tbl != ht->future_tbl &&
+	    ht->p.grow_decision && ht->p.grow_decision(ht, tbl->size))
+		schedule_delayed_work(&ht->run_work, 0);
+
+	rcu_read_unlock();
 }
 EXPORT_SYMBOL_GPL(rhashtable_insert);
 
@@ -361,32 +540,56 @@
  */
 bool rhashtable_remove(struct rhashtable *ht, struct rhash_head *obj)
 {
-	struct bucket_table *tbl = rht_dereference(ht->tbl, ht);
+	struct bucket_table *tbl;
 	struct rhash_head __rcu **pprev;
 	struct rhash_head *he;
-	u32 h;
+	spinlock_t *lock;
+	unsigned int hash;
 
-	ASSERT_RHT_MUTEX(ht);
+	rcu_read_lock();
+	tbl = rht_dereference_rcu(ht->tbl, ht);
+	hash = head_hashfn(ht, tbl, obj);
 
-	h = head_hashfn(ht, tbl, obj);
+	lock = bucket_lock(tbl, hash);
+	spin_lock_bh(lock);
 
-	pprev = &tbl->buckets[h];
-	rht_for_each(he, tbl, h) {
+restart:
+	pprev = &tbl->buckets[hash];
+	rht_for_each(he, tbl, hash) {
 		if (he != obj) {
 			pprev = &he->next;
 			continue;
 		}
 
-		RCU_INIT_POINTER(*pprev, he->next);
-		ht->nelems--;
+		rcu_assign_pointer(*pprev, obj->next);
+		atomic_dec(&ht->nelems);
 
-		if (ht->p.shrink_decision &&
+		spin_unlock_bh(lock);
+
+		if (ht->tbl != ht->future_tbl &&
+		    ht->p.shrink_decision &&
 		    ht->p.shrink_decision(ht, tbl->size))
-			rhashtable_shrink(ht);
+			schedule_delayed_work(&ht->run_work, 0);
+
+		rcu_read_unlock();
 
 		return true;
 	}
 
+	if (tbl != rht_dereference_rcu(ht->tbl, ht)) {
+		spin_unlock_bh(lock);
+
+		tbl = rht_dereference_rcu(ht->tbl, ht);
+		hash = head_hashfn(ht, tbl, obj);
+
+		lock = bucket_lock(tbl, hash);
+		spin_lock_bh(lock);
+		goto restart;
+	}
+
+	spin_unlock_bh(lock);
+	rcu_read_unlock();
+
 	return false;
 }
 EXPORT_SYMBOL_GPL(rhashtable_remove);
@@ -402,25 +605,35 @@
  * This lookup function may only be used for fixed key hash table (key_len
  * paramter set). It will BUG() if used inappropriately.
  *
- * Lookups may occur in parallel with hash mutations as long as the lookup is
- * guarded by rcu_read_lock(). The caller must take care of this.
+ * Lookups may occur in parallel with hashtable mutations and resizing.
  */
-void *rhashtable_lookup(const struct rhashtable *ht, const void *key)
+void *rhashtable_lookup(struct rhashtable *ht, const void *key)
 {
-	const struct bucket_table *tbl = rht_dereference_rcu(ht->tbl, ht);
+	const struct bucket_table *tbl, *old_tbl;
 	struct rhash_head *he;
-	u32 h;
+	u32 hash;
 
 	BUG_ON(!ht->p.key_len);
 
-	h = key_hashfn(ht, key, ht->p.key_len);
-	rht_for_each_rcu(he, tbl, h) {
+	rcu_read_lock();
+	old_tbl = rht_dereference_rcu(ht->tbl, ht);
+	tbl = rht_dereference_rcu(ht->future_tbl, ht);
+	hash = key_hashfn(ht, key, ht->p.key_len);
+restart:
+	rht_for_each_rcu(he, tbl, rht_bucket_index(tbl, hash)) {
 		if (memcmp(rht_obj(ht, he) + ht->p.key_offset, key,
 			   ht->p.key_len))
 			continue;
+		rcu_read_unlock();
 		return rht_obj(ht, he);
 	}
 
+	if (unlikely(tbl != old_tbl)) {
+		tbl = old_tbl;
+		goto restart;
+	}
+
+	rcu_read_unlock();
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(rhashtable_lookup);
@@ -435,25 +648,36 @@
  * Traverses the bucket chain behind the provided hash value and calls the
  * specified compare function for each entry.
  *
- * Lookups may occur in parallel with hash mutations as long as the lookup is
- * guarded by rcu_read_lock(). The caller must take care of this.
+ * Lookups may occur in parallel with hashtable mutations and resizing.
  *
  * Returns the first entry on which the compare function returned true.
  */
-void *rhashtable_lookup_compare(const struct rhashtable *ht, const void *key,
+void *rhashtable_lookup_compare(struct rhashtable *ht, const void *key,
 				bool (*compare)(void *, void *), void *arg)
 {
-	const struct bucket_table *tbl = rht_dereference_rcu(ht->tbl, ht);
+	const struct bucket_table *tbl, *old_tbl;
 	struct rhash_head *he;
 	u32 hash;
 
+	rcu_read_lock();
+
+	old_tbl = rht_dereference_rcu(ht->tbl, ht);
+	tbl = rht_dereference_rcu(ht->future_tbl, ht);
 	hash = key_hashfn(ht, key, ht->p.key_len);
-	rht_for_each_rcu(he, tbl, hash) {
+restart:
+	rht_for_each_rcu(he, tbl, rht_bucket_index(tbl, hash)) {
 		if (!compare(rht_obj(ht, he), arg))
 			continue;
+		rcu_read_unlock();
 		return rht_obj(ht, he);
 	}
 
+	if (unlikely(tbl != old_tbl)) {
+		tbl = old_tbl;
+		goto restart;
+	}
+	rcu_read_unlock();
+
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(rhashtable_lookup_compare);
@@ -485,9 +709,6 @@
  *	.key_offset = offsetof(struct test_obj, key),
  *	.key_len = sizeof(int),
  *	.hashfn = jhash,
- * #ifdef CONFIG_PROVE_LOCKING
- *	.mutex_is_held = &my_mutex_is_held,
- * #endif
  * };
  *
  * Configuration Example 2: Variable length keys
@@ -507,9 +728,6 @@
  *	.head_offset = offsetof(struct test_obj, node),
  *	.hashfn = jhash,
  *	.obj_hashfn = my_hash_fn,
- * #ifdef CONFIG_PROVE_LOCKING
- *	.mutex_is_held = &my_mutex_is_held,
- * #endif
  * };
  */
 int rhashtable_init(struct rhashtable *ht, struct rhashtable_params *params)
@@ -529,18 +747,29 @@
 	if (params->nelem_hint)
 		size = rounded_hashtable_size(params);
 
-	tbl = bucket_table_alloc(size);
+	memset(ht, 0, sizeof(*ht));
+	mutex_init(&ht->mutex);
+	memcpy(&ht->p, params, sizeof(*params));
+
+	if (params->locks_mul)
+		ht->p.locks_mul = roundup_pow_of_two(params->locks_mul);
+	else
+		ht->p.locks_mul = BUCKET_LOCKS_PER_CPU;
+
+	tbl = bucket_table_alloc(ht, size);
 	if (tbl == NULL)
 		return -ENOMEM;
 
-	memset(ht, 0, sizeof(*ht));
 	ht->shift = ilog2(tbl->size);
-	memcpy(&ht->p, params, sizeof(*params));
 	RCU_INIT_POINTER(ht->tbl, tbl);
+	RCU_INIT_POINTER(ht->future_tbl, tbl);
 
 	if (!ht->p.hash_rnd)
 		get_random_bytes(&ht->p.hash_rnd, sizeof(ht->p.hash_rnd));
 
+	if (ht->p.grow_decision || ht->p.shrink_decision)
+		INIT_DEFERRABLE_WORK(&ht->run_work, rht_deferred_worker);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(rhashtable_init);
@@ -553,9 +782,16 @@
  * has to make sure that no resizing may happen by unpublishing the hashtable
  * and waiting for the quiescent cycle before releasing the bucket array.
  */
-void rhashtable_destroy(const struct rhashtable *ht)
+void rhashtable_destroy(struct rhashtable *ht)
 {
-	bucket_table_free(ht->tbl);
+	ht->being_destroyed = true;
+
+	mutex_lock(&ht->mutex);
+
+	cancel_delayed_work(&ht->run_work);
+	bucket_table_free(rht_dereference(ht->tbl, ht));
+
+	mutex_unlock(&ht->mutex);
 }
 EXPORT_SYMBOL_GPL(rhashtable_destroy);
 
@@ -570,13 +806,6 @@
 #define TEST_PTR	((void *) 0xdeadbeef)
 #define TEST_NEXPANDS	4
 
-#ifdef CONFIG_PROVE_LOCKING
-static int test_mutex_is_held(void *parent)
-{
-	return 1;
-}
-#endif
-
 struct test_obj {
 	void			*ptr;
 	int			value;
@@ -646,10 +875,10 @@
 				i, tbl->buckets[i], cnt);
 	}
 
-	pr_info("  Traversal complete: counted=%u, nelems=%zu, entries=%d\n",
-		total, ht->nelems, TEST_ENTRIES);
+	pr_info("  Traversal complete: counted=%u, nelems=%u, entries=%d\n",
+		total, atomic_read(&ht->nelems), TEST_ENTRIES);
 
-	if (total != ht->nelems || total != TEST_ENTRIES)
+	if (total != atomic_read(&ht->nelems) || total != TEST_ENTRIES)
 		pr_warn("Test failed: Total count mismatch ^^^");
 }
 
@@ -688,7 +917,9 @@
 
 	for (i = 0; i < TEST_NEXPANDS; i++) {
 		pr_info("  Table expansion iteration %u...\n", i);
+		mutex_lock(&ht->mutex);
 		rhashtable_expand(ht);
+		mutex_unlock(&ht->mutex);
 
 		rcu_read_lock();
 		pr_info("  Verifying lookups...\n");
@@ -698,7 +929,9 @@
 
 	for (i = 0; i < TEST_NEXPANDS; i++) {
 		pr_info("  Table shrinkage iteration %u...\n", i);
+		mutex_lock(&ht->mutex);
 		rhashtable_shrink(ht);
+		mutex_unlock(&ht->mutex);
 
 		rcu_read_lock();
 		pr_info("  Verifying lookups...\n");
@@ -741,9 +974,6 @@
 		.key_offset = offsetof(struct test_obj, value),
 		.key_len = sizeof(int),
 		.hashfn = jhash,
-#ifdef CONFIG_PROVE_LOCKING
-		.mutex_is_held = &test_mutex_is_held,
-#endif
 		.grow_decision = rht_grow_above_75,
 		.shrink_decision = rht_shrink_below_30,
 	};
diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c
index 7f903cf..75887d7 100644
--- a/net/netfilter/nft_hash.c
+++ b/net/netfilter/nft_hash.c
@@ -33,7 +33,7 @@
 			    const struct nft_data *key,
 			    struct nft_data *data)
 {
-	const struct rhashtable *priv = nft_set_priv(set);
+	struct rhashtable *priv = nft_set_priv(set);
 	const struct nft_hash_elem *he;
 
 	he = rhashtable_lookup(priv, key);
@@ -113,7 +113,7 @@
 
 static int nft_hash_get(const struct nft_set *set, struct nft_set_elem *elem)
 {
-	const struct rhashtable *priv = nft_set_priv(set);
+	struct rhashtable *priv = nft_set_priv(set);
 	struct nft_compare_arg arg = {
 		.set = set,
 		.elem = elem,
@@ -129,7 +129,7 @@
 static void nft_hash_walk(const struct nft_ctx *ctx, const struct nft_set *set,
 			  struct nft_set_iter *iter)
 {
-	const struct rhashtable *priv = nft_set_priv(set);
+	struct rhashtable *priv = nft_set_priv(set);
 	const struct bucket_table *tbl;
 	const struct nft_hash_elem *he;
 	struct nft_set_elem elem;
@@ -162,13 +162,6 @@
 	return sizeof(struct rhashtable);
 }
 
-#ifdef CONFIG_PROVE_LOCKING
-static int lockdep_nfnl_lock_is_held(void *parent)
-{
-	return lockdep_nfnl_is_held(NFNL_SUBSYS_NFTABLES);
-}
-#endif
-
 static int nft_hash_init(const struct nft_set *set,
 			 const struct nft_set_desc *desc,
 			 const struct nlattr * const tb[])
@@ -182,9 +175,6 @@
 		.hashfn = jhash,
 		.grow_decision = rht_grow_above_75,
 		.shrink_decision = rht_shrink_below_30,
-#ifdef CONFIG_PROVE_LOCKING
-		.mutex_is_held = lockdep_nfnl_lock_is_held,
-#endif
 	};
 
 	return rhashtable_init(priv, &params);
@@ -192,16 +182,23 @@
 
 static void nft_hash_destroy(const struct nft_set *set)
 {
-	const struct rhashtable *priv = nft_set_priv(set);
-	const struct bucket_table *tbl = priv->tbl;
+	struct rhashtable *priv = nft_set_priv(set);
+	const struct bucket_table *tbl;
 	struct nft_hash_elem *he;
 	struct rhash_head *pos, *next;
 	unsigned int i;
 
+	/* Stop an eventual async resizing */
+	priv->being_destroyed = true;
+	mutex_lock(&priv->mutex);
+
+	tbl = rht_dereference(priv->tbl, priv);
 	for (i = 0; i < tbl->size; i++) {
 		rht_for_each_entry_safe(he, pos, next, tbl, i, node)
 			nft_hash_elem_destroy(set, he);
 	}
+	mutex_unlock(&priv->mutex);
+
 	rhashtable_destroy(priv);
 }
 
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 57449b6..738c3bf 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -114,15 +114,6 @@
 DEFINE_MUTEX(nl_sk_hash_lock);
 EXPORT_SYMBOL_GPL(nl_sk_hash_lock);
 
-#ifdef CONFIG_PROVE_LOCKING
-static int lockdep_nl_sk_hash_is_held(void *parent)
-{
-	if (debug_locks)
-		return lockdep_is_held(&nl_sk_hash_lock) || lockdep_is_held(&nl_table_lock);
-	return 1;
-}
-#endif
-
 static ATOMIC_NOTIFIER_HEAD(netlink_chain);
 
 static DEFINE_SPINLOCK(netlink_tap_lock);
@@ -1063,7 +1054,8 @@
 		goto err;
 
 	err = -ENOMEM;
-	if (BITS_PER_LONG > 32 && unlikely(table->hash.nelems >= UINT_MAX))
+	if (BITS_PER_LONG > 32 &&
+	    unlikely(atomic_read(&table->hash.nelems) >= UINT_MAX))
 		goto err;
 
 	nlk_sk(sk)->portid = portid;
@@ -3122,9 +3114,6 @@
 		.max_shift = 16, /* 64K */
 		.grow_decision = rht_grow_above_75,
 		.shrink_decision = rht_shrink_below_30,
-#ifdef CONFIG_PROVE_LOCKING
-		.mutex_is_held = lockdep_nl_sk_hash_is_held,
-#endif
 	};
 
 	if (err != 0)