From 3d368ab87cf6681f928de1ddf804d69600671bb2 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 10 Feb 2021 06:41:44 -0800 Subject: net: initialize net->net_cookie at netns setup It is simpler to make net->net_cookie a plain u64 written once in setup_net() instead of looping and using atomic64 helpers. Lorenz Bauer wants to add SO_NETNS_COOKIE socket option and this patch would makes his patch series simpler. Signed-off-by: Eric Dumazet Cc: Daniel Borkmann Cc: Lorenz Bauer Acked-by: Daniel Borkmann Tested-by: Lorenz Bauer Signed-off-by: David S. Miller --- net/core/net_namespace.c | 19 +++---------------- 1 file changed, 3 insertions(+), 16 deletions(-) (limited to 'net/core/net_namespace.c') diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 2ef3b4557f40..43b6ac4c4439 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -72,18 +72,6 @@ static unsigned int max_gen_ptrs = INITIAL_NET_GEN_PTRS; DEFINE_COOKIE(net_cookie); -u64 __net_gen_cookie(struct net *net) -{ - while (1) { - u64 res = atomic64_read(&net->net_cookie); - - if (res) - return res; - res = gen_cookie_next(&net_cookie); - atomic64_cmpxchg(&net->net_cookie, 0, res); - } -} - static struct net_generic *net_alloc_generic(void) { struct net_generic *ng; @@ -332,6 +320,9 @@ static __net_init int setup_net(struct net *net, struct user_namespace *user_ns) refcount_set(&net->ns.count, 1); refcount_set(&net->passive, 1); get_random_bytes(&net->hash_mix, sizeof(u32)); + preempt_disable(); + net->net_cookie = gen_cookie_next(&net_cookie); + preempt_enable(); net->dev_base_seq = 1; net->user_ns = user_ns; idr_init(&net->netns_ids); @@ -1103,10 +1094,6 @@ static int __init net_ns_init(void) rcu_assign_pointer(init_net.gen, ng); - preempt_disable(); - __net_gen_cookie(&init_net); - preempt_enable(); - down_write(&pernet_ops_rwsem); if (setup_net(&init_net, &init_user_ns)) panic("Could not setup the initial network namespace"); -- cgit