Re: [PATCH] mm:vmalloc add vm_struct for vm_map_ram

From: Andrew Morton
Date: Thu Nov 08 2018 - 17:52:43 EST


On Thu, 8 Nov 2018 19:14:49 +0800 Zhaoyang Huang <huangzhaoyang@xxxxxxxxx> 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.