[PATCH 03/10] Docs/mm/damon/design: add a section for overall architecture

[SeongJae Park]

The design doc is missing overall picture of DAMON.  Add a section for
overall architeucture and layers.

Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
 Documentation/mm/damon/design.rst | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst
index 0cff6fac6b7e..3b4ce873fa71 100644
--- a/Documentation/mm/damon/design.rst
+++ b/Documentation/mm/damon/design.rst
@@ -4,6 +4,21 @@
 Design
 ======
 
+
+Overall Architecture
+====================
+
+DAMON subsystem is configured with three layers including
+
+- Operations Set: Implements fundamental operations for DAMON that depends on
+  the given monitoring target address-space and available set of
+  software/hardware primitives,
+- Core: Implements core logics including monitoring overhead/accurach control
+  and access-aware system operations on top of the operations set layer, and
+- Modules: Implements kernel modules for various purposes that provides
+  interfaces for the user space, on top of the core layer.
+
+
 Configurable Layers
 ===================
 
-- 
2.25.1