[RFC,0/5] mm/damon/sysfs: add a file for efficiently get total size of DAMOS tried regions

Message

SeongJae Park July 28, 2023, 8:18 p.m. UTC

The tried_regions directory of DAMON sysfs interface is useful for
retrieving monitoring results snapshot or DAMOS debugging.  However, for
common use case that need to monitor only the total size of the scheme
tried regions (e.g., monitoring working set size), the kernel overhead
for directory construction and user overhead for reading the content
could be high if the number of monitoring region is not small.  This
patchset implements DAMON sysfs files for efficient support of the use
case.

The first patch implements the sysfs file to reduce the user space
overhead, and the second patch implements a command for reducing the
kernel space overhead.

The third patch adds a selftest for the new file, and following two
patches update documents.

SeongJae Park (5):
  mm/damon/sysfs-schemes: implement DAMOS tried total bytes file
  mm/damon/sysfs: implement a command for updating only schemes tried
    total bytes
  selftests/damon/sysfs: test tried_regions/total_bytes file
  Docs/ABI/damon: update for tried_regions/total_bytes
  Docs/admin-guide/mm/damon/usage: update for tried_regions/total_bytes

 .../ABI/testing/sysfs-kernel-mm-damon         | 13 +++++-
 Documentation/admin-guide/mm/damon/usage.rst  | 42 ++++++++++++-------
 mm/damon/sysfs-common.h                       |  2 +-
 mm/damon/sysfs-schemes.c                      | 24 ++++++++++-
 mm/damon/sysfs.c                              | 26 +++++++++---
 tools/testing/selftests/damon/sysfs.sh        |  1 +
 6 files changed, 83 insertions(+), 25 deletions(-)