Re: [PATCH] x86: Deinline cpuid_eax and friends

[H. Peter Anvin]

On 05/06/2015 10:07 AM, Denys Vlasenko wrote:
> cpuid_e{a,b,c,d}x() functions compile to 44 bytes of machine code each.
> On x86 allyesconfig build they have 48 callsites.
> Deinlining all four of them shrinks kernel by about 1k:
> 
>    text      data      bss       dec     hex filename
> 82434909 22255384 20627456 125317749 7783275 vmlinux.before
> 82433898 22255384 20627456 125316738 7782e82 vmlinux
> 
> Speed impact: CPUID instruction takes from 50 to 350+ cycles,
> call overhead is negligible in comparison.

How on Earth does it make 44 bytes?  Is this due to paravirt_fail?

	-hpa


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