From 30c15f033847c519bae4a3dc23320e1fbee868eb Mon Sep 17 00:00:00 2001
From: David Ahern <dsahern@gmail.com>
Date: Tue, 9 Apr 2019 14:41:15 -0700
Subject: [PATCH] ipv6: Refactor find_rr_leaf
find_rr_leaf has 3 loops over fib_entries calling find_match. The loops
are very similar with differences in start point and whether the metric
is evaluated:
1. start at rr_head, no extra loop compare, check fib metric
2. start at leaf, compare rt against rr_head, check metric
3. start at cont (potential saved point from earlier loops), no
extra loop compare, no metric check
Create 1 loop that is called 3 different times. This will make a
later change with multipath nexthop objects much simpler.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/ipv6/route.c | 82 ++++++++++++++++++++++--------------------------
1 file changed, 38 insertions(+), 44 deletions(-)
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 200bd5bb56bf..52aa48a8dbda 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -668,58 +668,52 @@ out:
return rc;
}
-static struct fib6_info *find_rr_leaf(struct fib6_node *fn,
- struct fib6_info *leaf,
- struct fib6_info *rr_head,
- u32 metric, int oif, int strict,
- bool *do_rr)
+static void __find_rr_leaf(struct fib6_info *rt_start,
+ struct fib6_info *nomatch, u32 metric,
+ struct fib6_info **match, struct fib6_info **cont,
+ int oif, int strict, bool *do_rr, int *mpri)
{
- struct fib6_info *rt, *match, *cont;
- struct fib6_nh *nh;
+ struct fib6_info *rt;
+
+ for (rt = rt_start;
+ rt && rt != nomatch;
+ rt = rcu_dereference(rt->fib6_next)) {
+ struct fib6_nh *nh;
+
+ if (cont && rt->fib6_metric != metric) {
+ *cont = rt;
+ return;
+ }
+
+ if (fib6_check_expired(rt))
+ continue;
+
+ nh = &rt->fib6_nh;
+ if (find_match(nh, rt->fib6_flags, oif, strict, mpri, do_rr))
+ *match = rt;
+ }
+}
+
+static struct fib6_info *find_rr_leaf(struct fib6_node *fn,
+ struct fib6_info *leaf,
+ struct fib6_info *rr_head,
+ u32 metric, int oif, int strict,
+ bool *do_rr)
+{
+ struct fib6_info *match = NULL, *cont = NULL;
int mpri = -1;
- match = NULL;
- cont = NULL;
- for (rt = rr_head; rt; rt = rcu_dereference(rt->fib6_next)) {
- if (rt->fib6_metric != metric) {
- cont = rt;
- break;
- }
+ __find_rr_leaf(rr_head, NULL, metric, &match, &cont,
+ oif, strict, do_rr, &mpri);
- if (fib6_check_expired(rt))
- continue;
-
- nh = &rt->fib6_nh;
- if (find_match(nh, rt->fib6_flags, oif, strict, &mpri, do_rr))
- match = rt;
- }
-
- for (rt = leaf; rt && rt != rr_head;
- rt = rcu_dereference(rt->fib6_next)) {
- if (rt->fib6_metric != metric) {
- cont = rt;
- break;
- }
-
- if (fib6_check_expired(rt))
- continue;
-
- nh = &rt->fib6_nh;
- if (find_match(nh, rt->fib6_flags, oif, strict, &mpri, do_rr))
- match = rt;
- }
+ __find_rr_leaf(leaf, rr_head, metric, &match, &cont,
+ oif, strict, do_rr, &mpri);
if (match || !cont)
return match;
- for (rt = cont; rt; rt = rcu_dereference(rt->fib6_next)) {
- if (fib6_check_expired(rt))
- continue;
-
- nh = &rt->fib6_nh;
- if (find_match(nh, rt->fib6_flags, oif, strict, &mpri, do_rr))
- match = rt;
- }
+ __find_rr_leaf(cont, NULL, metric, &match, NULL,
+ oif, strict, do_rr, &mpri);
return match;
}