Re: [PATCH v2] kthread: Export kthread functions

From: Neil Horman
Date: Sat Aug 01 2015 - 09:32:32 EST


On Sat, Aug 01, 2015 at 03:12:42PM +0800, yalin wang wrote:
>
> > å 2015å7æ31æï22:14ïThomas Gleixner <tglx@xxxxxxxxxxxxx> åéï
> >
> >
> > On Fri, 31 Jul 2015, Thomas Gleixner wrote:
> >
> >> On Fri, 31 Jul 2015, yalin wang wrote:
> >>> it is optimised to 2 instructions ,
> >>>
> >>> this is my patch, hope can be merged :
> >>
> >> We are not exposing the internals of kthread management. Period.
> >
> > And your 'optimization' is completely bogus:
> >
> > Before your modification:
> >
> > size kernel/built-in.o
> >
> > text data bss dec hex filename
> > 1091514 141498 341928 1574940 18081c ../build/kernel/built-in.o
> >
> > After:
> >
> > text data bss dec hex filename
> > 1091664 141498 341928 1575090 1808b2 ../build/kernel/built-in.o
> >
> > That's an increase of text size by 150 byte. Interesting optimization.
> >
> > Thanks,
> >
> > tglx
> >
> >
> strange, this is my test result:
>
> size built-in.o*
> text data bss dec hex filename
> 743937 50786 56008 850731 cfb2b built-in.o // with the patch
> 744069 50786 56008 850863 cfbaf built-in.o_old // with out the patch
>
So you're willing to expose the internals of kthread_park in exchange for the
hope of saving 132 bytes of text.

Thats just dumb. I agree with tglx, this shouldn't change.

Neil

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