[PATCH] ARM: multi_v7_defconfig: Enable debugging symbols by default

[PATCH] ARM: multi_v7_defconfig: Enable debugging symbols by default

[Florian Fainelli]

Similarly to the ARM64 defconfig, enable debugging symbols and rely upon
the toolchain's default DWARF implementation.

Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
---
 arch/arm/configs/multi_v7_defconfig | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
index 62734530a3d6..eee71f6ae131 100644
--- a/arch/arm/configs/multi_v7_defconfig
+++ b/arch/arm/configs/multi_v7_defconfig
@@ -1322,5 +1322,8 @@ CONFIG_CRYPTO_DEV_STM32_HASH=m
 CONFIG_CRYPTO_DEV_STM32_CRYP=m
 CONFIG_CMA_SIZE_MBYTES=64
 CONFIG_PRINTK_TIME=y
+CONFIG_DEBUG_KERNEL=y
+CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
+CONFIG_DEBUG_INFO_REDUCED=y
 CONFIG_MAGIC_SYSRQ=y
 CONFIG_DEBUG_FS=y
-- 
2.43.0

Re: [PATCH] ARM: multi_v7_defconfig: Enable debugging symbols by default

[Arnd Bergmann]

On Fri, Sep 6, 2024, at 21:39, Florian Fainelli wrote:
> Similarly to the ARM64 defconfig, enable debugging symbols and rely upon
> the toolchain's default DWARF implementation.
>
> Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>

I usually build with debug info disabled when I'm build testing,
but turn it on explicitly when I try to actually debug a problem.

Depending on the configuration, adding debug info can significantly
increase the build time and file size. I've tried to record exact
data here, building the arm defconfig on gcc-14 with and without
debug info, which doesn't seem too bad, especially with the
reduced debug info:

config         vmlinux time    total time   vmlinux size
disabled-gcc9  49s             81s          35MB
reduced-gcc9   55s             98s          148MB
full-gcc9      66s             105s         443MB
disabled-gcc14 55s             90s          34MB
reduced-gcc14  60s             99s          124MB
full-gcc14     68s             115s         349MB

There is still added disk usage for build testing, but
the time overhead seems fine. I'd like to hear what others
think about the tradeoff.

      Arnd