Attach a program to a raw perf event rather than a kernel or userspace function

[pittma]

Hey all, I've been digging around the redbpf source today, trying to track down a way to use it to map an ebpf program to a regular old perf event (a hardware event in my case). In the Python BCC library, you can use attach_perf_event_raw and map a perf_event_attr to a function:

prog_text="""
int hw_event(struct bpf_perf_event_data *ctx) {
    // do stuff with `ctx`
}
"""

attr = Perf.perf_event_attr()
attr.type=PerfType.RAW

# hw_hexcode here is the perf event + mask
attr.config = int(hw_hexcode, 16)

b = BPF(text=prog_text)
b.attach_perf_event_raw(perf_event_attr=attr, fn_name=hw_event, pid=pid, cpu=cpu)

How might I do this with redbpf?

[GermanCoding]

Hi,

as far as I know redBPF does not support raw tracepoints at this time. I had a look at the requirements and it does not look to be terribly different from what we already have, so likely doable, but it just isn't there at this time.

[AlexandruCihodaru]

Hello @GermanCoding I would like to contribute this. :D

[GermanCoding]

I am not a maintainer of redBPF, but sure go ahead. From my experience the maintainers do review and merge code.

Revisiting the original question, I think I misread it. I thought about raw tracepoints, but it looks like the actual question was about BPF_PROG_TYPE_PERF_EVENT (perf event programs). I don't remember redBPF support for these either.