linux-kernel - Re: [PATCH v2 0/3] Sony-laptop: Adjustments for sony_nc_setup

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Date:   Sun, 5 Nov 2017 15:24:19 +0200
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     SF Markus Elfring <elfring@...rs.sourceforge.net>
Cc:     Darren Hart <dvhart@...radead.org>,
        Platform Driver <platform-driver-x86@...r.kernel.org>,
        Marco Chiappero <marco@...ence.it>,
        Matthew Garrett <mjg@...hat.com>,
        Mattia Dongili <malattia@...ux.it>,
        LKML <linux-kernel@...r.kernel.org>,
        kernel-janitors@...r.kernel.org,
        Andy Shevchenko <andy@...radead.org>
Subject: Re: [PATCH v2 0/3] Sony-laptop: Adjustments for sony_nc_setup_rfkill()

On Fri, Nov 3, 2017 at 3:23 PM, SF Markus Elfring
<elfring@...rs.sourceforge.net> wrote:
>> I have applied first two,
>
> Thanks for another change acceptance.
>
>
>> the last one is subject to discuss a necessity of it.
>
> I can offer another bit of information for this software development discussion.
>
> The following build settings were active in my “Makefile” for this Linux test case.
>
> …
> HOSTCFLAGS   = -Wall -Wmissing-prototypes -Wstrict-prototypes -O0 -fomit-frame-pointer -std=gnu89
> …
>
>
> The affected source file can be compiled for the processor architecture “x86_64”
> by a tool like “GCC 6.4.1+r251631-1.3” from the software distribution
> “openSUSE Tumbleweed” with the following command example.
>
> my_cc=/usr/bin/gcc-6 \
> && my_module=drivers/platform/x86/sony-laptop.ko \
> && git checkout ':/^Sony-laptop: Delete an unnecessary variable initialisation in sony_nc_setup_rfkill' \
> && make -j4 CC="${my_cc}" HOSTCC="${my_cc}" allmodconfig "${my_module}" \
> && size "${my_module}" \
> && git checkout ':/^Sony-laptop: Use common error handling code in sony_nc_setup_rfkill' \
> && make -j4 CC="${my_cc}" HOSTCC="${my_cc}" allmodconfig "${my_module}" \
> && size "${my_module}"
>
>
> Do you find the following details useful for further clarification?
>
> text: -32
> data: 0
> bss:  0

...but kernel is compiled with -O2 which, I suppose, will eliminate
these repeats.

So, the main question is "WHY" you are doing this change.

I didn't find any convinced explanation (yet?).

As an example, I would understand it if the consequent patch will
bring locking to the function.

-- 
With Best Regards,
Andy Shevchenko