On Fri, 2024-09-06 at 14:24 +0100, Mykyta Yatsenko wrote:
> From: Mykyta Yatsenko <yatsenko@xxxxxxxx>
>
> Existing algorithm for BTF C dump sorting uses only types and names of
> the structs and unions for ordering. As dump contains structs with the
> same names but different contents, relative to each other ordering of
> those structs will be accidental.
> This patch addresses this problem by introducing a new sorting field
> that contains hash of the struct/union field names and types to
> disambiguate comparison of the non-unique named structs.
>
> Signed-off-by: Mykyta Yatsenko <yatsenko@xxxxxxxx>
> ---
Note, this is still not fully stable, e.g.:
$ for i in $(seq 1 10); \
do touch ./kernel/bpf/verifier.c && \
ccache-kernel-make.sh -j23 && \
./tools/bpf/bpftool/bpftool btf dump file vmlinux format c > ~/work/tmp/vmlinux.h.$i; \
done
...
$ md5sum ~/work/tmp/vmlinux.h.* | sort -k1
76c9b22274c4aa6253ffaafa33ceffd3 /home/eddy/work/tmp/vmlinux.h.2
76c9b22274c4aa6253ffaafa33ceffd3 /home/eddy/work/tmp/vmlinux.h.4
a1c90a62e6cca59869a9cdffbaa3c4de /home/eddy/work/tmp/vmlinux.h.1
a1c90a62e6cca59869a9cdffbaa3c4de /home/eddy/work/tmp/vmlinux.h.10
a1c90a62e6cca59869a9cdffbaa3c4de /home/eddy/work/tmp/vmlinux.h.3
a1c90a62e6cca59869a9cdffbaa3c4de /home/eddy/work/tmp/vmlinux.h.5
a1c90a62e6cca59869a9cdffbaa3c4de /home/eddy/work/tmp/vmlinux.h.6
a1c90a62e6cca59869a9cdffbaa3c4de /home/eddy/work/tmp/vmlinux.h.7
a1c90a62e6cca59869a9cdffbaa3c4de /home/eddy/work/tmp/vmlinux.h.8
a1c90a62e6cca59869a9cdffbaa3c4de /home/eddy/work/tmp/vmlinux.h.9
[...]
