On Fri, Apr 7, 2023 at 12:43 AM Andrii Nakryiko <andrii@xxxxxxxxxx> wrote: > > Add output-only log_true_size and btf_log_true_size field to > BPF_PROG_LOAD and BPF_BTF_LOAD commands, respectively. It will return > the size of log buffer necessary to fit in all the log contents at > specified log_level. This is very useful for BPF loader libraries like > libbpf to be able to size log buffer correctly, but could be used by > users directly, if necessary, as well. > > This patch plumbs all this through the code, taking into account actual > bpf_attr size provided by user to determine if these new fields are > expected by users. And if they are, set them from kernel on return. > > We refactory btf_parse() function to accommodate this, moving attr and > uattr handling inside it. The rest is very straightforward code, which > is split from the logging accounting changes in the previous patch to > make it simpler to review logic vs UAPI changes. > > Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx> Acked-by: Lorenz Bauer <lmb@xxxxxxxxxxxxx>
