ipv6: broadly use fib6_info_hold() helper

Instead of using atomic_inc(), prefer fib6_info_hold()
so that upcoming refcount_t conversion is simpler.

Only fib6_info_alloc() is using atomic_set() since we
just allocated a new object.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Wei Wang <weiwan@google.com>
Acked-by: Wei Wang <weiwan@google.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 5519385..a5e8359 100644 (file)
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -162,7 +162,7 @@ struct fib6_info *fib6_info_alloc(gfp_t gfp_flags)
        }
 
        INIT_LIST_HEAD(&f6i->fib6_siblings);
-       atomic_inc(&f6i->fib6_ref);
+       atomic_set(&f6i->fib6_ref, 1);
 
        return f6i;
 }
@@ -846,8 +846,8 @@ insert_above:
 
                RCU_INIT_POINTER(in->parent, pn);
                in->leaf = fn->leaf;
-               atomic_inc(&rcu_dereference_protected(in->leaf,
-                               lockdep_is_held(&table->tb6_lock))->fib6_ref);
+               fib6_info_hold(rcu_dereference_protected(in->leaf,
+                               lockdep_is_held(&table->tb6_lock)));
 
                /* update parent pointer */
                if (dir)
@@ -942,7 +942,7 @@ static void fib6_purge_rt(struct fib6_info *rt, struct fib6_node *fn,
                        struct fib6_info *new_leaf;
                        if (!(fn->fn_flags & RTN_RTINFO) && leaf == rt) {
                                new_leaf = fib6_find_prefix(net, table, fn);
-                               atomic_inc(&new_leaf->fib6_ref);
+                               fib6_info_hold(new_leaf);
 
                                rcu_assign_pointer(fn->leaf, new_leaf);
                                fib6_info_release(rt);
@@ -1108,7 +1108,7 @@ add:
                        return err;
 
                rcu_assign_pointer(rt->fib6_next, iter);
-               atomic_inc(&rt->fib6_ref);
+               fib6_info_hold(rt);
                rcu_assign_pointer(rt->fib6_node, fn);
                rcu_assign_pointer(*ins, rt);
                if (!info->skip_notify)
@@ -1136,7 +1136,7 @@ add:
                if (err)
                        return err;
 
-               atomic_inc(&rt->fib6_ref);
+               fib6_info_hold(rt);
                rcu_assign_pointer(rt->fib6_node, fn);
                rt->fib6_next = iter->fib6_next;
                rcu_assign_pointer(*ins, rt);
@@ -1278,7 +1278,7 @@ int fib6_add(struct fib6_node *root, struct fib6_info *rt,
                        if (!sfn)
                                goto failure;
 
-                       atomic_inc(&info->nl_net->ipv6.fib6_null_entry->fib6_ref);
+                       fib6_info_hold(info->nl_net->ipv6.fib6_null_entry);
                        rcu_assign_pointer(sfn->leaf,
                                           info->nl_net->ipv6.fib6_null_entry);
                        sfn->fn_flags = RTN_ROOT;
@@ -1321,7 +1321,7 @@ int fib6_add(struct fib6_node *root, struct fib6_info *rt,
                                rcu_assign_pointer(fn->leaf,
                                            info->nl_net->ipv6.fib6_null_entry);
                        } else {
-                               atomic_inc(&rt->fib6_ref);
+                               fib6_info_hold(rt);
                                rcu_assign_pointer(fn->leaf, rt);
                        }
                }