[RFC PATCH 15/16] Docs/admin-guide/mm/damon/usage: document weight sysfs file

From: SJ Park

Date: Sun Jul 05 2026 - 17:02:24 EST


Update DAMON usage document for newly added probe weight file.

Signed-off-by: SJ Park <sj@xxxxxxxxxx>
---
Documentation/admin-guide/mm/damon/usage.rst | 11 ++++++++---
Documentation/mm/damon/design.rst | 5 +++++
2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/Documentation/admin-guide/mm/damon/usage.rst b/Documentation/admin-guide/mm/damon/usage.rst
index b2649ea011f93..4515088eba968 100644
--- a/Documentation/admin-guide/mm/damon/usage.rst
+++ b/Documentation/admin-guide/mm/damon/usage.rst
@@ -73,9 +73,10 @@ comma (",").
│ │ │ │ │ │ │ intervals_goal/access_bp,aggrs,min_sample_us,max_sample_us
│ │ │ │ │ │ nr_regions/min,max
│ │ │ │ │ │ :ref:`probes <damon_usage_sysfs_probes>`/nr_probes
- │ │ │ │ │ │ │ 0/filters/nr_filters
- │ │ │ │ │ │ │ │ 0/type,matching,allow,path
- │ │ │ │ │ │ │ │ ...
+ │ │ │ │ │ │ │ 0/weight
+ │ │ │ │ │ │ │ │ filters/nr_filters
+ │ │ │ │ │ │ │ │ │ 0/type,matching,allow,path
+ │ │ │ │ │ │ │ │ │ ...
│ │ │ │ │ │ │ ...
│ │ │ │ │ :ref:`targets <sysfs_targets>`/nr_targets
│ │ │ │ │ │ :ref:`0 <sysfs_target>`/pid_target,obsolete_target
@@ -286,6 +287,10 @@ In each probe directory, one directory, ``filters`` exists. The directory
contains files for installing filters for the probe, that is used to determine
the data attribute for the probe.

+Each probe directory also contains ``weight`` file. Reading from and writing
+to the file gets and sets the :ref:`atttributes-only monitoring
+<damon_design_attrs_only_monitoring>` weight for the attribute of the probe.
+
In the beginning, ``filters`` directory has only one file, ``nr_filters``.
Writing a number (``N``) to the file creates the number of child directories
named ``0`` to ``N-1``. Each directory represents each filter and works in a
diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst
index 67398e2133036..129acb1da4e19 100644
--- a/Documentation/mm/damon/design.rst
+++ b/Documentation/mm/damon/design.rst
@@ -316,6 +316,8 @@ Another way to do this for higher accuracy is using :ref:`DAMOS filter
information in page level. But, because it is operated in page level, the
overhead is proportional to the size of the memory.

+.. _damon_design_attrs_only_monitoring:
+
Data Attributes-only Monitoring
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

@@ -336,6 +338,9 @@ automatically turned off. The access counter (``nr_accesses``) will always be
zero and not updated. Hence the mode is called Data Attributes "only"
monitoring.

+Refer to the :ref:`admin guide <damon_usage_sysfs_probes>` to know how users
+can use the mode.
+
Dynamic Target Space Updates Handling
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

--
2.47.3