inet: remove old fragmentation hash initializing
authorHannes Frederic Sowa <hannes@stressinduktion.org>
Wed, 23 Oct 2013 09:06:57 +0000 (11:06 +0200)
committerDavid S. Miller <davem@davemloft.net>
Wed, 23 Oct 2013 21:01:41 +0000 (17:01 -0400)
All fragmentation hash secrets now get initialized by their
corresponding hash function with net_get_random_once. Thus we can
eliminate the initial seeding.

Also provide a comment that hash secret seeding happens at the first
call to the corresponding hashing function.

Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/net/inet_frag.h
net/ipv4/inet_fragment.c

index bfcbc0017950372ddd39dd540ff3f6da99f2bee6..6f59de98dabde3be0daa202f8be4528d49676f7f 100644 (file)
@@ -64,6 +64,10 @@ struct inet_frags {
        rwlock_t                lock ____cacheline_aligned_in_smp;
        int                     secret_interval;
        struct timer_list       secret_timer;
+
+       /* The first call to hashfn is responsible to initialize
+        * rnd. This is best done with net_get_random_once.
+        */
        u32                     rnd;
        int                     qsize;
 
index c5313a9c019b9b94aca569aba011b63fc452e1c5..bb075fc9a14f25169c175c7fcdcb86d56c709627 100644 (file)
@@ -93,9 +93,6 @@ void inet_frags_init(struct inet_frags *f)
        }
        rwlock_init(&f->lock);
 
-       f->rnd = (u32) ((totalram_pages ^ (totalram_pages >> 7)) ^
-                                  (jiffies ^ (jiffies >> 6)));
-
        setup_timer(&f->secret_timer, inet_frag_secret_rebuild,
                        (unsigned long)f);
        f->secret_timer.expires = jiffies + f->secret_interval;