Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> writes: > On Mon, Dec 13, 2021 at 8:28 AM Toke Høiland-Jørgensen <toke@xxxxxxxxxx> wrote: >> >> Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> writes: >> >> > On Sat, Dec 11, 2021 at 10:43 AM Toke Høiland-Jørgensen <toke@xxxxxxxxxx> wrote: >> >> >> >> This adds an XDP-based traffic generator sample which uses the DO_REDIRECT >> >> flag of bpf_prog_run(). It works by building the initial packet in >> >> userspace and passing it to the kernel where an XDP program redirects the >> >> packet to the target interface. The traffic generator supports two modes of >> >> operation: one that just sends copies of the same packet as fast as it can >> >> without touching the packet data at all, and one that rewrites the >> >> destination port number of each packet, making the generated traffic span a >> >> range of port numbers. >> >> >> >> The dynamic mode is included to demonstrate how the bpf_prog_run() facility >> >> enables building a completely programmable packet generator using XDP. >> >> Using the dynamic mode has about a 10% overhead compared to the static >> >> mode, because the latter completely avoids touching the page data. >> >> >> >> Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> >> >> --- >> >> samples/bpf/.gitignore | 1 + >> >> samples/bpf/Makefile | 4 + >> >> samples/bpf/xdp_redirect.bpf.c | 34 +++ >> >> samples/bpf/xdp_trafficgen_user.c | 421 ++++++++++++++++++++++++++++++ >> >> 4 files changed, 460 insertions(+) >> >> create mode 100644 samples/bpf/xdp_trafficgen_user.c >> > >> > I think it deserves to be in tools/bpf/ >> > samples/bpf/ bit rots too often now. >> > imo everything in there either needs to be converted to selftests/bpf >> > or deleted. >> >> I think there's value in having a separate set of utilities that are >> more user-facing than the selftests. But I do agree that it's annoying >> they bit rot. So how about we fix that instead? Andrii suggested just >> integrating the build of samples/bpf into selftests[0], so I'll look >> into that after the holidays. But in the meantime I don't think there's >> any harm in adding this utility here? > > I think samples/bpf building would help to stabilize bitroting, > but the question of the right home for this trafficgen tool remains. > I think it's best to keep it outside of the kernel tree. > It's not any more special than all other libbpf and bcc tools. > I think xdp-tools repo or bcc could be a home for it. Alright, I'll drop it from the next version and put it into xdp-tools. I've been contemplating doing the same for some of the other tools (xdp_redirect* and xdp_monitor, for instance). Any opinion on that? -Toke
