Michael Zimmermann <sigmaepsilon92@xxxxxxxxx> writes: > On Thu, May 12, 2022 at 5:21 AM Andrii Nakryiko > <andrii.nakryiko@xxxxxxxxx> wrote: >> >> On Mon, May 9, 2022 at 10:12 PM Michael Zimmermann >> <sigmaepsilon92@xxxxxxxxx> wrote: >> > >> > Thank you for your answer. >> > What I'm ultimately trying to do is: Use aya-rs to watch egress on a >> > network interface and notify userspace through a map (for certain IPs >> > only). >> > >> > In my actual use case, the userspace is supposed to do more complex >> > stuff but for testing I simply logged the receival of a message >> > through the BPF map on the console. And that is what I expect to >> > happen and which does happen as long as CONFIG_TRACING/CONFIG_FTRACE >> > are active. If not, I simply never receive any messages on any map. >> > >> > I've also tried this using an XDP program which sends a message every >> > time it sees a packet. And while the program seemed to be >> > working(since it did block certain traffic), I never saw any data in >> > the map when those configs were disabled. >> > >> > Also, I'm giving you two configs(tracing and ftrace) since the other >> > one seems to get y-selected automatically if one of them is active. >> >> Please don't top post, reply inline instead. > Sorry for that, GMail does that by default and even hides that it's > quoting at all. > >> >> I don't think we have enough to investigate here, even "receive any >> messages on any map" is so ambiguous that it's hard to even guess what >> you are really trying to do. BPF maps are not sending/receiving >> messages. So please provide some pieces of code and what you are doing >> to check. CONFIG_TRACING and CONFIG_FTRACE shouldn't have any effect >> on functioning of BPF maps, so it's most probably that you are doing >> something besides BPF map update/lookup, but you don't provide enough >> information to check anything. > > An aya project I tested where I don't receive any events: > https://github.com/aya-rs/book/tree/6b52a6fac5fa3e5a1165f98591b2eaff9692048a/examples/myapp-03 It's using a PERF_EVENT_ARRAY map to send events to userspace. This requires CONFIG_BPF_EVENTS to work, which depends on CONFIG_PERF_EVENTS. Not sure if this depends on CONFIG_TRACING specifically, but maybe you disabled PERF_EVENTS as well? -Toke
