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Date:   Thu, 12 Oct 2023 12:24:42 +0300
From:   Mike Rapoport <rppt@kernel.org>
To:     Yajun Deng <yajun.deng@linux.dev>
Cc:     akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] memblock: don't run loop in memblock_add_range() twice
Message-ID: <20231012092442.GR3303@kernel.org>
References: <20231003163045.191184-1-yajun.deng@linux.dev>
 <20231005051959.GC3303@kernel.org>
 <df623d80-befb-09e0-04eb-3c93ecfa9f2e@linux.dev>
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On Thu, Oct 05, 2023 at 11:20:19PM +0800, Yajun Deng wrote:
> 
> On 2023/10/5 13:19, Mike Rapoport wrote:
> 
> > I don't see this micro-optimization is worth the churn and potential bugs.
> > NAK.
> 
> There are many handouts that tell people it needs to run twice in
> memblock_add_range().
> 
> I think it's time to change this. I'm trying to tell people that running
> twice is unnecessary.

It might be unnecessary, but it's still simpler than the solutions you
proposed. And, again, removing the second loop is not worth the churn and
potential bugs.
 
-- 
Sincerely yours,
Mike.