tcp: replace ehash_size by ehash_mask

Storing the mask (size - 1) instead of the size allows fast path to be
a bit faster.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 6 deletions

diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index a156319fd0ac..ecb203fff501 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -1060,11 +1060,12 @@ static int __init dccp_init(void)
         for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++)
                 ;
         do {
-                dccp_hashinfo.ehash_size = (1UL << ehash_order) * PAGE_SIZE /
+                unsigned long hash_size = (1UL << ehash_order) * PAGE_SIZE /
                                         sizeof(struct inet_ehash_bucket);
-                while (dccp_hashinfo.ehash_size &
-                       (dccp_hashinfo.ehash_size - 1))
-                        dccp_hashinfo.ehash_size--;
+
+                while (hash_size & (hash_size - 1))
+                        hash_size--;
+                dccp_hashinfo.ehash_mask = hash_size - 1;
                 dccp_hashinfo.ehash = (struct inet_ehash_bucket *)
                         __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order);
         } while (!dccp_hashinfo.ehash && --ehash_order > 0);
@@ -1074,7 +1075,7 @@ static int __init dccp_init(void)
                 goto out_free_bind_bucket_cachep;
         }
 
-        for (i = 0; i < dccp_hashinfo.ehash_size; i++) {
+        for (i = 0; i <= dccp_hashinfo.ehash_mask; i++) {
                 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].chain, i);
                 INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].twchain, i);
         }
@@ -1153,7 +1154,7 @@ static void __exit dccp_fini(void)
                    get_order(dccp_hashinfo.bhash_size *
                              sizeof(struct inet_bind_hashbucket)));
         free_pages((unsigned long)dccp_hashinfo.ehash,
-                   get_order(dccp_hashinfo.ehash_size *
+                   get_order((dccp_hashinfo.ehash_mask + 1) *
                              sizeof(struct inet_ehash_bucket)));
         inet_ehash_locks_free(&dccp_hashinfo);
         kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);