Update DAMON design document for the newly added DAMN probe preps feature. Signed-off-by: SJ Park --- Documentation/mm/damon/design.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst index 12a2c3f81a262..5ce777c6b3f30 100644 --- a/Documentation/mm/damon/design.rst +++ b/Documentation/mm/damon/design.rst @@ -311,6 +311,13 @@ Users can therefore know how much of a given DAMON region has a specific data attribute by reading the per-region per-probe probe hits counter after each aggregation interval. +Users can optionally register probing preparation actions per probe. If such +actions are registered, DAMON applies the actions to each region's sampling +memory before starting the next sampling interval. Currently only one action, +``set_pgidle`` is supported. The action marks the page for the probing target +memory as access-idle. This can be useful to be used together with +``pgidle_unset`` probe filter. + This is a sampling based mechanism. Hence, it is lightweight but the output may include some measurement errors. The output should be used with good understanding of statistics. -- 2.47.3