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

On Tue, Feb 13, 2024 at 02:35:29PM -0800, Suren Baghdasaryan wrote:

On Tue, Feb 13, 2024 at 2:29 PM Darrick J. Wong [off-list ref] wrote:

quoted

On Mon, Feb 12, 2024 at 05:01:19PM -0800, Suren Baghdasaryan wrote:

quoted

On Mon, Feb 12, 2024 at 2:40 PM Kees Cook [off-list ref] wrote:

quoted

On Mon, Feb 12, 2024 at 01:38:59PM -0800, Suren Baghdasaryan wrote:

quoted

Introduce CONFIG_MEM_ALLOC_PROFILING which provides definitions to easily
instrument memory allocators. It registers an "alloc_tags" codetag type
with /proc/allocinfo interface to output allocation tag information when

Please don't add anything new to the top-level /proc directory. This
should likely live in /sys.

Ack. I'll find a more appropriate place for it then.
It just seemed like such generic information which would belong next
to meminfo/zoneinfo and such...

Save yourself a cycle of "rework the whole fs interface only to have
someone else tell you no" and put it in debugfs, not sysfs.  Wrangling
with debugfs is easier than all the macro-happy sysfs stuff; you don't
have to integrate with the "device" model; and there is no 'one value
per file' rule.

Thanks for the input. This file used to be in debugfs but reviewers
felt it belonged in /proc if it's to be used in production
environments. Some distros (like Android) disable debugfs in
production.

FWIW, I agree debugfs is not right. If others feel it's right in /proc,
I certainly won't NAK -- it's just been that we've traditionally been
trying to avoid continuing to pollute the top-level /proc and instead
associate new things with something in /sys.

-- 
Kees Cook