Commit 1370c45d authored by Ido Schimmel's avatar Ido Schimmel Committed by Jakub Kicinski
Browse files

vxlan: Read jiffies once when updating FDB 'used' time 



Avoid two volatile reads in the data path. Instead, read jiffies once
and only if an FDB entry was found.

Reviewed-by: default avatarPetr Machata <petrm@nvidia.com>
Signed-off-by: default avatarIdo Schimmel <idosch@nvidia.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarNikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20250204145549.1216254-3-idosch@nvidia.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent f6205f82

drivers/net/vxlan/vxlan_core.c

+6 −2
Original line number Diff line number Diff line
@@ -434,8 +434,12 @@ static struct vxlan_fdb *vxlan_find_mac(struct vxlan_dev *vxlan, 
	struct vxlan_fdb *f;



	f = __vxlan_find_mac(vxlan, mac, vni);

	if (f && READ_ONCE(f->used) != jiffies)

		WRITE_ONCE(f->used, jiffies);

	if (f) {

		unsigned long now = jiffies;



		if (READ_ONCE(f->used) != now)

			WRITE_ONCE(f->used, now);

	}



	return f;

}