cache: add hashtable cache for sets

This patch adds a hashtable for set lookups.

This patch also splits table->sets in two:

- Sets that reside in the cache are stored in the new
  tables->cache_set and tables->cache_set_ht.

- Set that defined via command line / ruleset file reside in
  tables->set.

Sets in the cache (already in the kernel) are not placed in the
table->sets list.

By keeping separated lists, sets defined via command line / ruleset file
can be added to cache.

Adding 10000 sets, before:

 # time nft -f x
 real    0m6,415s
 user    0m3,126s
 sys     0m3,284s

After:

 # time nft -f x
 real    0m3,949s
 user    0m0,743s
 sys     0m3,205s

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/cache.h b/include/cache.h
index 087f9ba9..f500e1b1 100644
--- a/include/cache.h
+++ b/include/cache.h
@@ -59,5 +59,7 @@ void cache_release(struct nft_cache *cache);
 void chain_cache_add(struct chain *chain, struct table *table);
 struct chain *chain_cache_find(const struct table *table,
 			       const struct handle *handle);
+void set_cache_add(struct set *set, struct table *table);
+struct set *set_cache_find(const struct table *table, const char *name);
 
 #endif /* _NFT_CACHE_H_ */