On Mon, Dec 13, 2021 at 4:37 PM Toke Høiland-Jørgensen <toke@xxxxxxxxxx> wrote: > > 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? Please move them too if you don't mind. samples/ just doesn't have the right production quality vibe. Everything in there is a sample code. In other words a toy application. I hope xdp_trafficgen aims to be a solid maintained tool with a man page that distros will ship eventually. So starting with a good home is important.
