[RFC PATCH 04/17] Docs/mm/damon/design: document pgidle_unset probe filter type

[SJ Park <sj@kernel.org>]

Update DAMON design document for the newly added pgidle_unset probe
filter type.  Also use a list for the types, as it becomes not very easy
to read the whole types in a simple sentence.

Signed-off-by: SJ Park <sj@kernel.org>
---
 Documentation/mm/damon/design.rst | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst
index a8c163475ef2b..12a2c3f81a262 100644
--- a/Documentation/mm/damon/design.rst
+++ b/Documentation/mm/damon/design.rst
@@ -293,8 +293,14 @@ registration is made by specifying a probe per attribute.  Each of the probe
 specifies a rule to determine if a given memory region has the related
 attribute.  The rule is constructed with multiple filters.  The filters work
 same to :ref:`DAMOS filters <damon_design_damos_filters>` except the supported
-filter types.  Currently only ``anon`` and ``memcg`` filter types are supported
-for data attributes monitoring.
+filter types.  Currently below fitler types are supported.
+
+- ``anon``: Same to that for DAMOS filters.
+- ``memcg``: Same to that for DAMOS filters.
+- ``pgidle_unset``: Matches if the page for the memory is marked as not
+  access-idle.
+  Matches if the memory is not backed by pages that DAMON can idnetify
+  idleness.
 
 If such probes are registered, DAMON executes the probes for each region's
 sampling memory when it does the access :ref:`sampling
-- 
2.47.3