Re: [PATCH bpf-next v4 6/8] bpftool: Implement btfgen()
flat view
From: Andrii Nakryiko <hidden>
Date: 2022-01-15 02:15:29
Also in:
bpf
On Wed, Jan 12, 2022 at 6:27 AM Mauricio Vásquez [off-list ref] wrote:
btfgen() receives the path of a source and destination BTF files and a list of BPF objects. This function records the relocations for all objects and then generates the BTF file by calling btfgen_get_btf() (implemented in the following commits). btfgen_record_obj() loads the BTF and BTF.ext sections of the BPF objects and loops through all CO-RE relocations. It uses bpf_core_calc_relo_insn() from libbpf and passes the target spec to btfgen_record_reloc() that saves the types involved in such relocation. Signed-off-by: Mauricio Vásquez <redacted> Signed-off-by: Rafael David Tinoco <redacted> Signed-off-by: Lorenzo Fontana <redacted> Signed-off-by: Leonardo Di Donato <redacted> --- tools/bpf/bpftool/gen.c | 221 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 219 insertions(+), 2 deletions(-)
[...]
quoted hunk ↗ jump to hunk
+ info = btfgen_new_info(src_btf); + if (!info) { + p_err("failed to allocate info structure: %s", strerror(errno)); + err = -errno; + goto out; + } + + for (int i = 0; objspaths[i] != NULL; i++) { + printf("OBJ : %s\n", objspaths[i]);
same as in previous patches, OBJ, DBTF, that's quite cryptic. Is this used for some parsing of the output or it's just debugging leftovers?
+
+ err = btfgen_record_obj(info, objspaths[i]);
+ if (err)
+ goto out;
+ }
+
+ btf_new = btfgen_get_btf(info);
+ if (!btf_new) {
+ err = -errno;
+ p_err("error generating btf: %s", strerror(errno));
+ goto out;
+ }
+
+ printf("DBTF: %s\n", dst_btf);
+ err = btf_save_raw(btf_new, dst_btf);
+ if (err) {
+ p_err("error saving btf file: %s", strerror(errno));
+ goto out;
+ }
+
+out:
+ btf__free(btf_new);
+ btfgen_free_info(info);
+
+ return err;
+}
+
static int is_file(const char *path)
{
struct stat st;
--
2.25.1