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Date:   Thu, 25 Oct 2018 12:42:49 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Vitaly Wool <vitalywool@gmail.com>
Cc:     Linux-MM <linux-mm@kvack.org>, linux-kernel@vger.kernel.org,
        Oleksiy.Avramchenko@sony.com, Guenter Roeck <linux@roeck-us.net>
Subject: Re: [PATCH] z3fold: encode object length in the handle
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On Thu, 25 Oct 2018 11:28:21 +0200 Vitaly Wool <vitalywool@gmail.com> wrote:

> Reclaim and free can race on an object (which is basically ok) but
> in order for reclaim to be able to  map "freed" object we need to
> encode object length in the handle. handle_to_chunks() is thus
> introduced to extract object length from a handle and use it during
> mapping of the last object we couldn't correctly map before.

What are the runtime effects of this change?

Thanks.