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Date:   Thu, 8 Nov 2018 14:52:39 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Zhaoyang Huang <huangzhaoyang@gmail.com>
Cc:     Chintan Pandya <cpandya@codeaurora.org>,
        David Rientjes <rientjes@google.com>,
        Joe Perches <joe@perches.com>, Michal Hocko <mhocko@suse.com>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm:vmalloc add vm_struct for vm_map_ram
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In-Reply-To: <1541675689-13363-1-git-send-email-huangzhaoyang@gmail.com>
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On Thu,  8 Nov 2018 19:14:49 +0800 Zhaoyang Huang <huangzhaoyang@gmail.com> wrote:

> There is no caller and pages information etc for the area which is
> created by vm_map_ram as well as the page count > VMAP_MAX_ALLOC.
> Add them on in this commit.

Well I can kind of see what this is doing - it increases the amount of
info in /proc/vmallocinfo for regions which were created by
vm_map_area(), yes?

But I'd like to hear it in your words, please.  What problem are we
trying to solve?  Why is it actually a problem?  Why is the additional
information considered useful, etc?

It would help a lot if the changelog were to include before-and-after
examples from the /proc/vmallocinfo output.

Thanks.