[PATCH net-next v2 1/4] nexthop: Factor out hash threshold fdb nexthop selection

From: Benjamin Poirier
Date: Wed Jul 19 2023 - 09:57:20 EST


The loop in nexthop_select_path_hthr() includes code to check for neighbor
validity. Since this does not apply to fdb nexthops, simplify the loop by
moving the fdb nexthop selection to its own function.

Signed-off-by: Ido Schimmel <idosch@xxxxxxxxxx>
Signed-off-by: Benjamin Poirier <bpoirier@xxxxxxxxxx>
Reviewed-by: David Ahern <dsahern@xxxxxxxxxx>
---
net/ipv4/nexthop.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c
index f95142e56da0..27089dea0ed0 100644
--- a/net/ipv4/nexthop.c
+++ b/net/ipv4/nexthop.c
@@ -1152,11 +1152,31 @@ static bool ipv4_good_nh(const struct fib_nh *nh)
return !!(state & NUD_VALID);
}

+static struct nexthop *nexthop_select_path_fdb(struct nh_group *nhg, int hash)
+{
+ int i;
+
+ for (i = 0; i < nhg->num_nh; i++) {
+ struct nh_grp_entry *nhge = &nhg->nh_entries[i];
+
+ if (hash > atomic_read(&nhge->hthr.upper_bound))
+ continue;
+
+ return nhge->nh;
+ }
+
+ WARN_ON_ONCE(1);
+ return NULL;
+}
+
static struct nexthop *nexthop_select_path_hthr(struct nh_group *nhg, int hash)
{
struct nexthop *rc = NULL;
int i;

+ if (nhg->fdb_nh)
+ return nexthop_select_path_fdb(nhg, hash);
+
for (i = 0; i < nhg->num_nh; ++i) {
struct nh_grp_entry *nhge = &nhg->nh_entries[i];
struct nh_info *nhi;
@@ -1165,8 +1185,6 @@ static struct nexthop *nexthop_select_path_hthr(struct nh_group *nhg, int hash)
continue;

nhi = rcu_dereference(nhge->nh->nh_info);
- if (nhi->fdb_nh)
- return nhge->nh;

/* nexthops always check if it is good and does
* not rely on a sysctl for this behavior

--
2.40.1