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From:   Valentin Schneider <vschneid@redhat.com>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     netdev@vger.kernel.org, linux-rdma@vger.kernel.org,
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        Gal Pressman <gal@nvidia.com>, Tariq Toukan <tariqt@nvidia.com>
Subject: Re: [PATCH v2 1/5] bitops: Introduce find_next_andnot_bit()
In-Reply-To: <20220818100820.3b45808b@gandalf.local.home>
References: <20220817175812.671843-1-vschneid@redhat.com>
 <20220817175812.671843-2-vschneid@redhat.com>
 <20220818100820.3b45808b@gandalf.local.home>
Date:   Thu, 18 Aug 2022 17:26:43 +0100
Message-ID: <xhsmh35dtbjr0.mognet@vschneid.remote.csb>
MIME-Version: 1.0
Content-Type: text/plain
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On 18/08/22 10:08, Steven Rostedt wrote:
> On Wed, 17 Aug 2022 18:58:08 +0100
> Valentin Schneider <vschneid@redhat.com> wrote:
>
>> +#ifndef find_next_andnot_bit
>> +/**
>> + * find_next_andnot_bit - find the next set bit in one memory region
>> + *                        but not in the other
>> + * @addr1: The first address to base the search on
>> + * @addr2: The second address to base the search on
>> + * @size: The bitmap size in bits
>> + * @offset: The bitnumber to start searching at
>> + *
>> + * Returns the bit number for the next set bit
>> + * If no bits are set, returns @size.
>
> Can we make the above documentation more descriptive. Because I read this
> three times, and I still have no idea what it does.
>
> The tag line sounds like the nursery song "One of these things is not like
> the others".
>

How about:

  find the next set bit in ((first region) AND NOT(second region))

Or

  find the next set bit in (*addr1 & ~*addr2)

?

> -- Steve