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Date: Thu, 11 Jun 2015 08:08:07 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>, Michal Marek <mmarek@suse.cz>,
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        Linus Torvalds <torvalds@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH v5 02/10] x86: Compile-time asm code validation
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* Josh Poimboeuf <jpoimboe@redhat.com> wrote:

> I should also mention that my proposed ia32_ptregs_common patch, which 
> duplicated the needed code, was more optimized for performance than code size.
> 
> But if you're more worried about code size, we could turn ia32_ptregs_common 
> into a proper callable function, and then replace
> 
>    jmp ia32_ptregs_common
> 
> with:
> 
>    call ia32_ptregs_common
>    ret
> 
> So it becomes a regular call instead of a tail call.  It only adds a few 
> instructions and the function is self-contained.  Would that be good enough?

No, debug info should not slow down the kernel, especially not code we write in 
assembly partly for performance.

Thanks,

	Ingo
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