ck_hs: Add ck_hs_rebuild operation.

This operation is short-hand notation for rebuilding
a hash table. This rebuild can occur in the presence
of concurrent readers and will require twice the amount
of memory of the existing hash table until completion.

include/ck_hs.h

@@ -123,6 +123,7 @@ bool ck_hs_set(ck_hs_t *, unsigned long, const void *, void **);
 bool ck_hs_fas(ck_hs_t *, unsigned long, const void *, void **);
 void *ck_hs_remove(ck_hs_t *, unsigned long, const void *);
 bool ck_hs_grow(ck_hs_t *, unsigned long);
+bool ck_hs_rebuild(ck_hs_t *);
 unsigned long ck_hs_count(ck_hs_t *);
 bool ck_hs_reset(ck_hs_t *);
 bool ck_hs_reset_size(ck_hs_t *, unsigned long);

src/ck_hs.c

@@ -366,6 +366,13 @@ restart:
 	return true;
 }
 
+bool
+ck_hs_rebuild(struct ck_hs *hs)
+{
+
+	return ck_hs_grow(hs, hs->map->capacity);
+}
+
 static void **
 ck_hs_map_probe(struct ck_hs *hs,
     struct ck_hs_map *map,