Re: [PATCH v3 13/35] lib: add allocation tagging support for memory allocation profiling

From: Andrew Morton
Date: Thu Feb 15 2024 - 19:56:20 EST


On Mon, 12 Feb 2024 13:38:59 -0800 Suren Baghdasaryan <surenb@xxxxxxxxxx> wrote:

> +Example output.
> +
> +::
> +
> + > cat /proc/allocinfo
> +
> + 153MiB mm/slub.c:1826 module:slub func:alloc_slab_page
> + 6.08MiB mm/slab_common.c:950 module:slab_common func:_kmalloc_order
> + 5.09MiB mm/memcontrol.c:2814 module:memcontrol func:alloc_slab_obj_exts
> + 4.54MiB mm/page_alloc.c:5777 module:page_alloc func:alloc_pages_exact
> + 1.32MiB include/asm-generic/pgalloc.h:63 module:pgtable func:__pte_alloc_one

I don't really like the fancy MiB stuff. Wouldn't it be better to just
present the amount of memory in plain old bytes, so people can use sort
-n on it? And it's easier to tell big-from-small at a glance because
big has more digits.

Also, the first thing any sort of downstream processing of this data is
going to have to do is to convert the fancified output back into
plain-old-bytes. So why not just emit plain-old-bytes?

If someone wants the fancy output (and nobody does) then that can be
done in userspace.