From 635a2f3ca4d46ce42df14bc2d9511af2f6ec3447 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Tue, 26 Oct 2021 16:10:57 +0200 Subject: [PATCH] MTU-tests: BPF-helper did make it upstream and in libbpf The BPF-helper is now defined in bpf_helper_defs.h header: lib/libbpf-install/usr/include/bpf/bpf_helper_defs.h Update and keep comment as a help for people doing kernel devel on BPF and want to test BPF-helpers not yet upstream. Accepted in kernel v5.12 - commit 34b2021cc616 ("bpf: Add BPF-helper for MTU checking") - https://git.kernel.org/torvalds/c/34b2021cc616 Signed-off-by: Jesper Dangaard Brouer --- MTU-tests/tc_mtu_enforce.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/MTU-tests/tc_mtu_enforce.c b/MTU-tests/tc_mtu_enforce.c index 44ffa53..1834a9e 100644 --- a/MTU-tests/tc_mtu_enforce.c +++ b/MTU-tests/tc_mtu_enforce.c @@ -3,13 +3,14 @@ #include #include -/* Testing BPF-helper that is not upstream yet, requires us to define +/* When testing a BPF-helper not upstream yet, it is possible to define * its call signature manually, which will only match our devel kernel. * * Generated signatur via command in kernel devel tree: - * ./scripts/bpf_helpers_doc.py --header | grep bpf_check_mtu + * ./scripts/bpf_doc.py --header | grep bpf_check_mtu */ -static int (*bpf_check_mtu)(void *ctx, __u32 ifindex, __u32 *mtu_len, __s32 len_diff, __u64 flags) = (void *) 163; +// Example: +// static long (*bpf_check_mtu)(void *ctx, __u32 ifindex, __u32 *mtu_len, __s32 len_diff, __u64 flags) = (void *) 163; enum bpf_check_mtu_flags { BPF_MTU_CHK_SEGS = (1U << 0),