From bfc08deedda8d81fbb0fbd21c395bb83d83805fa Mon Sep 17 00:00:00 2001
From: Jesper Dangaard Brouer <brouer@redhat.com>
Date: Tue, 13 Oct 2020 15:37:05 +0200
Subject: [PATCH] MTU-tests: Add README

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 MTU-tests/README.org | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 MTU-tests/README.org

diff --git a/MTU-tests/README.org b/MTU-tests/README.org
new file mode 100644
index 0000000..67b8c2d
--- /dev/null
+++ b/MTU-tests/README.org
@@ -0,0 +1,25 @@
+#+OPTIONS: ^:nil
+
+* BPF testing packet size changes
+
+Playing with increasing packet size with TC-BPF. Testing what happens when
+sending packets larger that MTU out an interface.
+
+* Notes loading BPF object
+
+How to manually load TC program:
+
+#+begin_src sh
+export DEV=mlx5p1
+tc qdisc del dev "$DEV" clsact # Also deletes all filters
+tc qdisc add dev "$DEV" clsact
+tc filter add dev "$DEV" pref 1 handle 1 egress bpf da obj tc_bpf_inc_pkt_size.o
+tc filter show dev "$DEV" egress
+#+end_src
+
+Be *VERY* careful with =replace= command, it MUST have same =pref= +=handle=:
+
+#+begin_src sh
+tc filter replace dev "$DEV" pref 1 handle 1 egress bpf da obj tc_bpf_inc_pkt_size.o
+#+end_src
+