Re: [PATCH 00/12] Introduce DAMON sysfs interface

SeongJae Park
2022-02-23T16:44:49Z

On Wed, 23 Feb 2022 17:07:20 +0100 Greg KH <gregkh@linuxfoundation.org> wrote:

> On Wed, Feb 23, 2022 at 03:20:39PM +0000, SeongJae Park wrote:
> > Chages from Previous Version (RFC)
> > ==================================
> >
> > Compared to the RFC version of this patchset
> > (https://lore.kernel.org/linux-mm/20220217161938.8874-1-sj@kernel.org/), this
> > version contains below changes.
> >
> > - Implement all DAMON debugfs interface providing features
> > - Writeup documents
> > - Add more selftests
> >
> > Introduction
> > ============
> >
> > DAMON's debugfs-based user interface (DAMON_DBGFS) served very well, so far.
> > However, it unnecessarily depends on debugfs, while DAMON is not aimed to be
> > used for only debugging. Also, the interface receives multiple values via one
> > file. For example, schemes file receives 18 values. As a result, it is
> > inefficient, hard to be used, and difficult to be extended. Especially,
> > keeping backward compatibility of user space tools is getting only challenging.
> > It would be better to implement another reliable and flexible interface and
> > deprecate DAMON_DBGFS in long term.
[...]
> >
> > SeongJae Park (12):
> > mm/damon/core: Allow non-exclusive DAMON start/stop
> > mm/damon/core: Add number of each enum type values
> > mm/damon: Implement a minimal stub for sysfs-based DAMON interface
> > mm/damon/sysfs: Link DAMON for virtual address spaces monitoring
> > mm/damon/sysfs: Support physical address space monitoring
> > mm/damon/sysfs: Support DAMON-based Operation Schemes
> > mm/damon/sysfs: Support DAMOS quotas
> > mm/damon/sysfs: Support schemes prioritization weights
> > mm/damon/sysfs: Support DAMOS watermarks
> > mm/damon/sysfs: Support DAMOS stats
> > selftests/damon: Add a test for DAMON sysfs interface
> > Docs/admin-guide/mm/damon/usage: Document DAMON sysfs interface
> >
> > Documentation/admin-guide/mm/damon/usage.rst | 349 ++-
> > include/linux/damon.h | 6 +-
> > mm/damon/Kconfig | 7 +
> > mm/damon/Makefile | 1 +
> > mm/damon/core.c | 23 +-
> > mm/damon/dbgfs.c | 2 +-
> > mm/damon/reclaim.c | 2 +-
> > mm/damon/sysfs.c | 2684 ++++++++++++++++++
> > tools/testing/selftests/damon/Makefile | 1 +
> > tools/testing/selftests/damon/sysfs.sh | 306 ++
> > 10 files changed, 3364 insertions(+), 17 deletions(-)
> > create mode 100644 mm/damon/sysfs.c
> > create mode 100755 tools/testing/selftests/damon/sysfs.sh
>
> sysfs files need to be documented in Documentation/ABI/ which is where
> our tools look for them (have you run scripts/get_abi.pl with your code
> in the kernel?)
>
> Please fix this up to use that format so we can then verify that you are
> using sysfs correctly.

Sure, I will do so in the next version.

Thanks,
SJ

>
> thanks,
>
> greg k-h