On Fri, Apr 07, 2023 at 09:05:17AM +0200, Andrea Righi wrote:
> Commit c1177979af9c ("btf, scripts: Exclude Rust CUs with pahole")
> introduced the constraint "!DEBUG_INFO_BTF || PAHOLE_HAS_LANG_EXCLUDE"
> to enable RUST.
>
> With this constraint we don't need is_rust_module.sh anymore, because
> 'pahole --lang_exclude=rust' already has the capability to exclude Rust
> CUs. If pahole isn't recent enough (< 1.24) to support --lang_exclude,
> then DEBUG_INFO_BTF can't be enabled with RUST and is_rust_module.sh
> isn't used as well.
>
> In any case is_rust_module.sh is obsolete and we can just drop it.
>
> Link: https://lore.kernel.org/lkml/Y+p2xKIN6TJnQinK@righiandr-XPS-13-7390/
> Signed-off-by: Andrea Righi <andrea.righi@xxxxxxxxxxxxx>
Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> ---
> rust/macros/module.rs | 2 +-
> scripts/Makefile.modfinal | 2 --
> scripts/is_rust_module.sh | 16 ----------------
> 3 files changed, 1 insertion(+), 19 deletions(-)
> delete mode 100755 scripts/is_rust_module.sh
>
> diff --git a/rust/macros/module.rs b/rust/macros/module.rs
> index a7e363c2b044..608406f33a70 100644
> --- a/rust/macros/module.rs
> +++ b/rust/macros/module.rs
> @@ -179,7 +179,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
> /// Used by the printing macros, e.g. [`info!`].
> const __LOG_PREFIX: &[u8] = b\"{name}\\0\";
>
> - /// The \"Rust loadable module\" mark, for `scripts/is_rust_module.sh`.
> + /// The \"Rust loadable module\" mark.
> //
> // This may be best done another way later on, e.g. as a new modinfo
> // key or a new section. For the moment, keep it simple.
It seems like this whole section can be dropped? I only see
__IS_RUST_MODULE used in scripts/is_rust_module.sh, as the comment
states.
> diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal
x> index 4703f652c009..e6f8fa3c9b8d 100644
> --- a/scripts/Makefile.modfinal
> +++ b/scripts/Makefile.modfinal
> @@ -41,8 +41,6 @@ quiet_cmd_btf_ko = BTF [M] $@
> cmd_btf_ko = \
> if [ ! -f vmlinux ]; then \
> printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \
> - elif [ -n "$(CONFIG_RUST)" ] && $(srctree)/scripts/is_rust_module.sh $@; then \
> - printf "Skipping BTF generation for %s because it's a Rust module\n" $@ 1>&2; \
> else \
> LLVM_OBJCOPY="$(OBJCOPY)" $(PAHOLE) -J $(PAHOLE_FLAGS) --btf_base vmlinux $@; \
> $(RESOLVE_BTFIDS) -b vmlinux $@; \
> diff --git a/scripts/is_rust_module.sh b/scripts/is_rust_module.sh
> deleted file mode 100755
> index 28b3831a7593..000000000000
> --- a/scripts/is_rust_module.sh
> +++ /dev/null
> @@ -1,16 +0,0 @@
> -#!/bin/sh
> -# SPDX-License-Identifier: GPL-2.0
> -#
> -# is_rust_module.sh module.ko
> -#
> -# Returns `0` if `module.ko` is a Rust module, `1` otherwise.
> -
> -set -e
> -
> -# Using the `16_` prefix ensures other symbols with the same substring
> -# are not picked up (even if it would be unlikely). The last part is
> -# used just in case LLVM decides to use the `.` suffix.
> -#
> -# In the future, checking for the `.comment` section may be another
> -# option, see https://github.com/rust-lang/rust/pull/97550.
> -${NM} "$*" | grep -qE '^[0-9a-fA-F]+ r _R[^[:space:]]+16___IS_RUST_MODULE[^[:space:]]*$'
> --
> 2.39.2
>
