openwrtv3/target/linux/generic/patches-3.18/080-23-fib_trie-Use-empty_children-instead-of-counting-empt.patch
Felix Fietkau 944612680d kernel: backport fib_trie improvements/fixes from 4.0-rc
Signed-off-by: Felix Fietkau <nbd@openwrt.org>

SVN-Revision: 44695
2015-03-12 15:27:44 +00:00

34 lines
1,023 B
Diff

From: Alexander Duyck <alexander.h.duyck@redhat.com>
Date: Thu, 22 Jan 2015 15:51:33 -0800
Subject: [PATCH] fib_trie: Use empty_children instead of counting empty nodes
in stats collection
It doesn't make much sense to count the pointers ourselves when
empty_children already has a count for the number of NULL pointers stored
in the tnode. As such save ourselves the cycles and just use
empty_children.
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1954,16 +1954,10 @@ static void trie_collect_stats(struct tr
hlist_for_each_entry_rcu(li, &n->list, hlist)
++s->prefixes;
} else {
- unsigned long i;
-
s->tnodes++;
if (n->bits < MAX_STAT_DEPTH)
s->nodesizes[n->bits]++;
-
- for (i = tnode_child_length(n); i--;) {
- if (!rcu_access_pointer(n->child[i]))
- s->nullpointers++;
- }
+ s->nullpointers += n->empty_children;
}
}
rcu_read_unlock();