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Date:   Thu, 7 Dec 2023 13:46:19 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Yury Norov <yury.norov@gmail.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org,
        Ming Lei <ming.lei@redhat.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>
Subject: Re: [PATCH v2 0/6] lib/group_cpus: rework grp_spread_init_one() and
 make it O(1)
Message-Id: <20231207134619.52545aaf4e5f393618a92c41@linux-foundation.org>
In-Reply-To: <20231207203900.859776-1-yury.norov@gmail.com>
References: <20231207203900.859776-1-yury.norov@gmail.com>
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On Thu,  7 Dec 2023 12:38:54 -0800 Yury Norov <yury.norov@gmail.com> wrote:

> grp_spread_init_one() implementation is sub-optimal because it
> traverses bitmaps from the beginning, instead of picking from the
> previous iteration.
> 
> Fix it and use find_bit API where appropriate. While here, optimize
> cpumasks allocation and drop unneeded cpumask_empty() call.

Thanks.  This isn't my playground, but I'll grab the patches to at
least get them some testing.  Review from those who have worked
on this code would be appreciated.