On Wed, Mar 8, 2023 at 3:53 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> Drop the symbols generated by scripts/kallsyms itself automatically
> instead of maintaining the symbol list manually.
>
> Pass the kallsyms object from the previous kallsyms step (if it exists)
> as the third parameter of scripts/mksysmap, which will weed out the
> generated symbols from the input to the next kallsyms step.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> ---
>
> scripts/kallsyms.c | 17 -----------------
> scripts/link-vmlinux.sh | 6 +++---
> scripts/mksysmap | 11 ++++++++++-
> 3 files changed, 13 insertions(+), 21 deletions(-)
>
> diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
> index 8148e880f78e..e572fda6fe42 100644
> --- a/scripts/kallsyms.c
> +++ b/scripts/kallsyms.c
> @@ -104,23 +104,6 @@ static bool is_ignored_symbol(const char *name, char type)
> {
> /* Symbol names that exactly match to the following are ignored.*/
> static const char * const ignored_symbols[] = {
> - /*
> - * Symbols which vary between passes. Passes 1 and 2 must have
> - * identical symbol lists. The kallsyms_* symbols below are
> - * only added after pass 1, they would be included in pass 2
> - * when --all-symbols is specified so exclude them to get a
> - * stable symbol list.
> - */
> - "kallsyms_addresses",
> - "kallsyms_offsets",
> - "kallsyms_relative_base",
> - "kallsyms_num_syms",
> - "kallsyms_names",
> - "kallsyms_markers",
> - "kallsyms_token_table",
> - "kallsyms_token_index",
> - "kallsyms_seqs_of_names",
> - /* Exclude linker generated symbols which vary between passes */
^ Do we want to retain this comment for the below two symbols?
> "_SDA_BASE_", /* ppc */
> "_SDA2_BASE_", /* ppc */
> NULL
> diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
> index 32e573943cf0..679eb4653b16 100755
> --- a/scripts/link-vmlinux.sh
> +++ b/scripts/link-vmlinux.sh
> @@ -174,7 +174,7 @@ kallsyms_step()
> kallsyms_S=${kallsyms_vmlinux}.S
>
> vmlinux_link ${kallsyms_vmlinux} "${kallsymso_prev}" ${btf_vmlinux_bin_o}
> - mksysmap ${kallsyms_vmlinux} ${kallsyms_vmlinux}.syms
> + mksysmap ${kallsyms_vmlinux} ${kallsyms_vmlinux}.syms ${kallsymso_prev}
> kallsyms ${kallsyms_vmlinux}.syms ${kallsyms_S}
>
> info AS ${kallsyms_S}
> @@ -188,7 +188,7 @@ kallsyms_step()
> mksysmap()
> {
> info NM ${2}
> - ${CONFIG_SHELL} "${srctree}/scripts/mksysmap" ${1} ${2}
> + ${CONFIG_SHELL} "${srctree}/scripts/mksysmap" ${1} ${2} ${3}
> }
>
> sorttable()
> @@ -277,7 +277,7 @@ if is_enabled CONFIG_DEBUG_INFO_BTF && is_enabled CONFIG_BPF; then
> ${RESOLVE_BTFIDS} vmlinux
> fi
>
> -mksysmap vmlinux System.map
> +mksysmap vmlinux System.map ${kallsymso}
>
> if is_enabled CONFIG_BUILDTIME_TABLE_SORT; then
> info SORTTAB vmlinux
> diff --git a/scripts/mksysmap b/scripts/mksysmap
> index 8ea1955e03c6..1efd61ee0bac 100755
> --- a/scripts/mksysmap
> +++ b/scripts/mksysmap
> @@ -4,7 +4,7 @@
> # tools to retrieve the actual addresses of symbols in the kernel.
> #
> # Usage
> -# mksysmap vmlinux System.map
> +# mksysmap vmlinux System.map [exclude]
>
>
> #####
> @@ -51,4 +51,13 @@ ${NM} -n ${1} | sed >${2} -e "
>
> # for LoongArch?
> / L0$/d
> +
> +# ---------------------------------------------------------------------------
> +# Ignored kallsyms symbols
> +#
> +# If the 3rd parameter exists, symbols from it will be omitted from the output.
> +# This makes kallsyms have the identical symbol lists in the step 1 and 2.
> +# Without this, the step2 would get new symbols generated by scripts/kallsyms.c
> +# when CONFIG_KALLSYMS_ALL is enabled. That might require one more pass.
> +$(if [ $# -ge 3 ]; then ${NM} ${3} | sed -n '/ U /!s:.* \([^ ]*\)$:/ \1$/d:p'; fi)
> "
> --
> 2.34.1
>
--
Thanks,
~Nick Desaulniers
