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Date:   Thu, 30 Mar 2023 12:59:18 +0200
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Subject: Re: [PATCH 0/4] log2: make is_power_of_2() more generic
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To:     Jani Nikula <jani.nikula@intel.com>, linux-kernel@vger.kernel.org
Cc:     intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
        Andrew Morton <akpm@linux-foundation.org>,
        David Gow <davidgow@google.com>
References: <20230330104243.2120761-1-jani.nikula@intel.com>
From:   =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>
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Am 30.03.23 um 12:42 schrieb Jani Nikula:
> is_power_of_2() only works for types <= sizeof(unsigned long) and it's
> also not a constant expression. There are a number of places in kernel
> where is_power_of_2() is called on u64, which fails on 32-bit
> builds. Try to remedy that. While at it, make it a constant expression
> when possible.
>
> I admit I've only lightly tested this, and I haven't tried it with
> allmodconfig.

Looks good to me from a one mile high level pov. But I'm really not an 
expert on that type of compiler magic, so only:

Acked-by: Christian König <christian.koenig@amd.com>

for the series.

Regards,
Christian.

>
>
> Jani Nikula (4):
>    log2: add helper __IS_POWER_OF_2()
>    log2: have is_power_of_2() support bigger types than unsigned long
>    log2: allow use of is_power_of_2() in constant expressions
>    drm/i915/reg: use is_power_of_2() from log2.h
>
>   drivers/gpu/drm/i915/i915_reg_defs.h |  7 +------
>   include/linux/log2.h                 | 25 ++++++++++++++++++++-----
>   2 files changed, 21 insertions(+), 11 deletions(-)
>