From 61407f80f72970d52d4339f81c6c3cd03f4ca0f0 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Thu, 3 Apr 2008 14:07:02 -0700 Subject: [PATCH] [NET]: srandom32 fixes for networking v2 - Let it update the state of all CPUs. The network stack goes into pains to feed the current IP addresses in, but it is not very effective if that is only done for some random CPU instead of all. So change it to feed bits into all CPUs. I decided to do that lockless because well somewhat random results are ok. v2: Drop rename so that this patch doesn't depend on x86 maintainers Signed-off-by: Andi Kleen Signed-off-by: David S. Miller --- lib/random32.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/lib/random32.c b/lib/random32.c index ec7f81d3fb1..ca87d86992b 100644 --- a/lib/random32.c +++ b/lib/random32.c @@ -97,13 +97,18 @@ EXPORT_SYMBOL(random32); * @seed: seed value * * Add some additional seeding to the random32() pool. - * Note: this pool is per cpu so it only affects current CPU. */ void srandom32(u32 entropy) { - struct rnd_state *state = &get_cpu_var(net_rand_state); - __set_random32(state, state->s1 ^ entropy); - put_cpu_var(state); + int i; + /* + * No locking on the CPUs, but then somewhat random results are, well, + * expected. + */ + for_each_possible_cpu (i) { + struct rnd_state *state = &per_cpu(net_rand_state, i); + __set_random32(state, state->s1 ^ entropy); + } } EXPORT_SYMBOL(srandom32); -- 2.41.1