Messages in this thread | | | From | Namhyung Kim <> | Date | Thu, 25 Aug 2022 10:21:36 -0700 | Subject | Re: [PATCH bpf-next] bpf: Add bpf_read_raw_record() helper |
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On Thu, Aug 25, 2022 at 10:05 AM Song Liu <songliubraving@fb.com> wrote: > > > On Aug 25, 2022, at 9:57 AM, Namhyung Kim <namhyung@kernel.org> wrote: > > > > On Tue, Aug 23, 2022 at 10:32 PM John Fastabend > > <john.fastabend@gmail.com> wrote: > >> Namhyung Kim wrote: > >>> Ok, now I think that I can use a bpf-output sw event. It would need > >>> another BPF program to write data to the event and the test program > >>> can read it from BPF using this helper. :) > >> > >> Ah good idea. Feel free to carry my ACK to the v2 with the test. > > > > Hmm.. it seems not to work because > > 1. bpf_output sw event doesn't have the overflow mechanism and it > > doesn't call the bpf program. > > 2. even if I added it, it couldn't run due to the recursion protection by > > bpf_prog_active. > > How about we enable some raw record for a software event? Something not > controlled by BPF?
Only for the test? It'd be nice if we could have meaningful data from software events but I don't have an idea what data it could carry on which event.
Peter, what do you think?
> > If this doesn't work, a self test that only runs on some hardware is also > helpful.
Yep, makes sense.
Thanks, Namhyung
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