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Date: Mon, 6 Apr 2015 09:20:30 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Steven Rostedt <rostedt@goodmis.org>, Borislav Petkov <bp@alien8.de>,
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        Kees Cook <keescook@chromium.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86/asm/entry/64: change interrupt entry macro to
 function
Message-ID: <20150406072029.GB1668@gmail.com>
References: <1428066324-7202-1-git-send-email-dvlasenk@redhat.com>
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* Denys Vlasenko <dvlasenk@redhat.com> wrote:

> The macro is largish, and we have 24 instances of it.
> 
> By moving almost its entire body into a function,
> 1500..3000 bytes are saved (depending on .config):
> 
>    text	   data	    bss	    dec	    hex	filename
>   12546	      0	      0	  12546	   3102	entry_64.o.before
>    9394	      0	      0	   9394	   24b2	entry_64.o
> 
> Run-tested.

Please list costs and benefits in the changelog. (i.e. increased cache 
locality vs. extra instruction[s] executed.)

Thanks,

	Ingo