Re: [PATCH v3 5/5] tools: update x86 string routines

From: Josh Poimboeuf
Date: Wed Feb 16 2022 - 01:00:04 EST


On Fri, Feb 11, 2022 at 03:14:45PM +0000, Mark Rutland wrote:
> When building the perf tool the build system complains that the x86
> string routines are out-of-date:
>
> | Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S'
> | diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S
> | Warning: Kernel ABI header at 'tools/arch/x86/lib/memset_64.S' differs from latest version at 'arch/x86/lib/memset_64.S'
> | diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S
>
> This is due to the way the asm-annotations for symbol aliasing were
> reworked, which should have no functional/performance impact.
>
> Import the latest versions, adding the new style SYM_FUNC_ALIAS(),
> SYM_FUNC_ALIAS_LOAD(), SYM_FUNC_ALIAS_WEAK() macros into the perf
> <linux/linkage.h> header. The old style SYM_FUNC_START_ALIAS() and
> SYM_FUNC_END_ALIAS() macros are removed.
>
> Other than removing the build-time warning, there should be no
> functional change as a result of this patch.

These changes should probably be squashed with their corresponding
original kernel changes to avoid breaking bisection for the warnings.
And it helps to keep the interdependent changes together.

--
Josh