Re: [PATCH v4 8/8] linux/log2.h: Use roundup/dow_pow_two() on 64bit calculations

From: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
To: Rob Herring <robh+dt@kernel.org>
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Subject: Re: [PATCH v4 8/8] linux/log2.h: Use roundup/dow_pow_two() on 64bit calculations
Date: Tue, 03 Dec 2019 17:06:43 +0100	[thread overview]
Message-ID: <d1c87c83f38e74f0c6b0692248fe88dfd2bdec3e.camel@suse.de> (raw)
In-Reply-To: <CAL_JsqLMCXdnZag3jihV_dzuR+wFaVKFb7q_PdKTxTg0LVA6cw@mail.gmail.com>

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Hi Rob,

On Tue, 2019-12-03 at 09:53 -0600, Rob Herring wrote:
> On Tue, Dec 3, 2019 at 5:48 AM Nicolas Saenz Julienne
> <nsaenzjulienne@suse.de> wrote:
> > The function now is safe to use while expecting a 64bit value. Use it
> > where relevant.
> 
> What was wrong with the existing code? This is missing some context.

You're right, I'll update it.

For most of files changed the benefit here is factoring out a common pattern
using the standard function roundup/down_pow_two() which now provides correct
64bit results.

As for of/device.c and arm64/iort.c it's more of a readability enhancement. I
consider it's easier to understand than the current calculation as it abstracts
the math.

> > Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
> > ---
> >  drivers/acpi/arm64/iort.c                        | 2 +-
> >  drivers/net/ethernet/mellanox/mlx4/en_clock.c    | 3 ++-
> >  drivers/of/device.c                              | 3 ++-
> 
> In any case,
> 
> Acked-by: Rob Herring <robh@kernel.org>
> 

Thanks!

Regards,
Nicolas

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