Hi.
Le mardi 12 juillet 2022, 22:47:40 CEST sdf@xxxxxxxxxx a écrit :
> On 07/12, Francis Laniel wrote:
> > This commit adds the following lines to file generated by dump:
> > /*
> >
> > * File generated by bpftool using:
> > * bpftool btf dump file /sys/kernel/btf/vmlinux format c
> > * DO NOT EDIT.
> > */
> >
> > This warns users to not edit the file and documents the command used to
> > generate the file.
> >
> > Signed-off-by: Francis Laniel <flaniel@xxxxxxxxxxxxxxxxxxx>
> > ---
> >
> > tools/bpf/bpftool/btf.c | 16 ++++++++++++++--
> > 1 file changed, 14 insertions(+), 2 deletions(-)
> >
> > diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
> > index 7e6accb9d9f7..eecfc27370c3 100644
> > --- a/tools/bpf/bpftool/btf.c
> > +++ b/tools/bpf/bpftool/btf.c
> > @@ -415,7 +415,8 @@ static void __printf(2, 0) btf_dump_printf(void *ctx,
> >
> > }
> >
> > static int dump_btf_c(const struct btf *btf,
> >
> > - __u32 *root_type_ids, int root_type_cnt)
> > + __u32 *root_type_ids, int root_type_cnt,
> > + int argc, char **argv)
> >
> > {
> >
> > struct btf_dump *d;
> > int err = 0, i;
> >
> > @@ -425,6 +426,14 @@ static int dump_btf_c(const struct btf *btf,
> >
> > if (err)
> >
> > return err;
> >
> > + printf("/*\n");
> > + printf(" * File generated by bpftool using:\n");
> > + printf(" * bpftool btf dump");
>
> [..]
>
> > + for (i = 0; i < argc; i++)
> > + printf(" %s", argv[i]);
>
> Do we really need that complexity to preserve the arguments?
I was also a bit sceptickal when I first wrote as I found this code a bit
complex for not so much added value.
But in my case, I do not use bpftool often, so having the command documented
in the generated file would have been useful.
I will just find another way to document (or I think now I will not forget it
anymore since this series).
> For skeletons we're simply doing:
>
> /* THIS FILE IS AUTOGENERATED BY BPFTOOL! */
>
> So probably the same should be fine here?
>
> Also, while at it, might be worth adding SPDX license comment? So let's
> align with whatever we have in gen.c ?
I will send a v2 aligned on skeletons in no more than 15 minutes.
> > + printf("\n");
> > + printf(" * DO NOT EDIT.\n");
> > + printf(" */\n");
> >
> > printf("#ifndef __VMLINUX_H__\n");
> > printf("#define __VMLINUX_H__\n");
> > printf("\n");
> >
> > @@ -507,8 +516,10 @@ static bool btf_is_kernel_module(__u32 btf_id)
> >
> > static int do_dump(int argc, char **argv)
> > {
> >
> > struct btf *btf = NULL, *base = NULL;
> >
> > + char **orig_argv = argv;
> >
> > __u32 root_type_ids[2];
> > int root_type_cnt = 0;
> >
> > + int orig_argc = argc;
> >
> > bool dump_c = false;
> > __u32 btf_id = -1;
> > const char *src;
> >
> > @@ -649,7 +660,8 @@ static int do_dump(int argc, char **argv)
> >
> > err = -ENOTSUP;
> > goto done;
> >
> > }
> >
> > - err = dump_btf_c(btf, root_type_ids, root_type_cnt);
> > + err = dump_btf_c(btf, root_type_ids, root_type_cnt,
> > + orig_argc, orig_argv);
> >
> > } else {
> >
> > err = dump_btf_raw(btf, root_type_ids, root_type_cnt);
> >
> > }
> >
> > --
> > 2.25.1
Best regards.
