Re: [PATCH v3 2/2] lib/string: shrink lib/string.i via IWYU

Andy Shevchenko
2023-12-19T15:55:16Z

On Mon, Dec 18, 2023 at 06:44:48PM +0000, tanzirh@google.com wrote:
> This diff uses an open source tool include-what-you-use (IWYU) to modify
> the include list changing indirect includes to direct includes.
> IWYU is implemented using the IWYUScripts github repository which is a tool that is
> currently undergoing development. These changes seek to improve build times.
>
> This change to lib/string.c resulted in a preprocessed size of
> lib/string.i from 26371 lines to 5263 lines (-80%) for the x86
> defconfig.

...

> #define __NO_FORTIFY
> #include <linux/types.h>
> -#include <linux/string.h>
> -#include <linux/ctype.h>
> -#include <linux/kernel.h>
> -#include <linux/export.h>
> +#include <linux/bits.h>
> #include <linux/bug.h>
> #include <linux/errno.h>
> -#include <linux/slab.h>

> -

Why this blank is removed?

> +#include <linux/linkage.h>
> +#include <linux/stddef.h>
> +#include <linux/string.h>
> +#include <linux/ctype.h>
> #include <asm/unaligned.h>
> -#include <asm/byteorder.h>
> +#include <asm/rwonce.h>
> #include <asm/word-at-a-time.h>
> #include <asm/page.h>

Sort this group alphabetically as well.

> +#include <vdso/limits.h>

Just use linux/limits.h.

VDSO is a very special UAPI case. So it's even stricter rule
than for asm/ for using anything from there.

Expected result:

#include <linux/bits.h>
#include <linux/bug.h>
#include <linux/ctype.h>
#include <linux/errno.h>
#include <linux/limits.h>
#include <linux/linkage.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/types.h>

#include <asm/page.h>
#include <asm/rwonce.h>
#include <asm/unaligned.h>
#include <asm/word-at-a-time.h>

--
With Best Regards,
Andy Shevchenko