Messages in this thread | | | From | Song Liu <> | Subject | Re: [PATCH v9 perf,bpf 09/15] perf, bpf: save btf information as headers to perf.data | Date | Fri, 15 Mar 2019 19:31:45 +0000 |
| |
Sorry for replying from the phone.
Sent from my iPhone
> On Mar 15, 2019, at 12:26 PM, Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com> wrote: > > Em Fri, Mar 15, 2019 at 04:06:51PM -0300, Arnaldo Carvalho de Melo escreveu: >> And yes, there are BPF programs with BTF information associated: > >> [root@quaco perf]# bpftool map dump pids_filtered >> [{ >> "key": 2592, >> "value": true >> },{ >> "key": 20511, >> "value": true >> } >> ] >> [root@quaco perf]# > >> I.e. bpftool can find the BTF info and thus is able to show the >> 'pids_filtered' map keys and values pretty printed, not just as hex raw >> data. > >> I'm trying to find out why 'bpftool map dump' finds the BTF info while >> perf_event__synthesize_one_bpf_prog() doesn't. > > Humm, the BTF info above is for BPF _maps_ not for _programs_, I think > you haven't added BTF info for maps in the perf.data header, right? > > - Arnaldo
That’s right. We iterate all BPF programs, and fetch BTF referred by the programs.
Thanks, Song | |