Re: [PATCH v3 2/6] trace: add CONFIG_BUILTIN_MODULE_RANGES option

From: Masahiro Yamada
Date: Mon May 20 2024 - 05:29:57 EST


On Fri, May 17, 2024 at 1:30 PM Kris Van Hees <kris.van.hees@oraclecom> wrote:
>
> The CONFIG_BUILTIN_MODULE_RANGES option controls whether offset range data
> is generated for kernel modules that are built into the kernel image.
>
> Signed-off-by: Kris Van Hees <kris.van.hees@xxxxxxxxxx>
> Reviewed-by: Nick Alcock <nick.alcock@xxxxxxxxxx>
> Reviewed-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
> ---
> Changes since v2:
> - Add explicit dependency on FTRACE for CONFIG_BUILTIN_MODULE_RANGES
> ---
> kernel/trace/Kconfig | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
> index 47345bf1d4a9f..d0c82b4b3a61e 100644
> --- a/kernel/trace/Kconfig
> +++ b/kernel/trace/Kconfig
> @@ -188,6 +188,24 @@ menuconfig FTRACE
>
> if FTRACE
>
> +config BUILTIN_MODULE_RANGES
> + bool "Generate address range information for builtin modules"
> + depends on FTRACE


This 'depends on' is redundant because this config is
already located between 'if FTRACE' and 'endif'.



I believe 2/6 thru 5/6 should be squashed into one commit.
Adding only the config option does not make much sense.




> + select VMLINUX_MAP
> + help
> + When modules are built into the kernel, there will be no module name
> + associated with its symbols in /proc/kallsyms. Tracers may want to
> + identify symbols by module name and symbol name regardless of whether
> + the module is configured as loadable or not.
> +
> + This option generates modules.builtin.ranges in the build tree with
> + offset ranges (per ELF section) for the module(s) they belong to.
> + It also records an anchor symbol to determine the load address of the
> + section.
> +
> + It is fully compatible with CONFIG_RANDOMIZE_BASE and similar late-
> + address-modification options.
> +
> config BOOTTIME_TRACING
> bool "Boot-time Tracing support"
> depends on TRACING
> --
> 2.43.0
>


--
Best Regards
Masahiro Yamada