Re: [PATCH 04/10] omap_hwspinlock: Replace "hweight_long(i & 0xf) != 1" with "!is_power_of_2(i & 0xf)"

From	Ohad Ben-Cohen <ohad@wizery.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH 04/10] omap_hwspinlock: Replace "hweight_long(i & 0xf) != 1" with "!is_power_of_2(i & 0xf)"
Date	2015-12-07 17:20 +0100
Message-ID	<qD6G7-6S6-35@gated-at.bofh.it> (permalink)
References	<qCETv-5Ko-5@gated-at.bofh.it> <qD1Q5-3GX-7@gated-at.bofh.it> <qD5Ao-6co-53@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Mon, Dec 7, 2015 at 5:03 PM, zhaoxiu.zeng <zhaoxiu.zeng@gmail.com> wrote:
> is_power_of_2 is simple, and faster than "hweightN(x) == 1" on most architectures.

Thanks. I'm not sure that speed is a major concern here, since this
code executes only once during the lifetime of the driver. Readability
is probably more important.
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[PATCH 04/10] omap_hwspinlock: Replace "hweight_long(i & 0xf) != 1" with "!is_power_of_2(i & 0xf)" Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com> - 2015-12-06 11:40 +0100
  Re: [PATCH 04/10] omap_hwspinlock: Replace "hweight_long(i & 0xf) !=  1" with "!is_power_of_2(i & 0xf)" Ohad Ben-Cohen <ohad@wizery.com> - 2015-12-07 12:10 +0100
    Re: [PATCH 04/10] omap_hwspinlock: Replace "hweight_long(i & 0xf) !=  1" with "!is_power_of_2(i & 0xf)" "zhaoxiu.zeng" <zhaoxiu.zeng@gmail.com> - 2015-12-07 16:10 +0100
      Re: [PATCH 04/10] omap_hwspinlock: Replace "hweight_long(i & 0xf) !=  1" with "!is_power_of_2(i & 0xf)" Ohad Ben-Cohen <ohad@wizery.com> - 2015-12-07 17:20 +0100

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