[RFC PATCH 1/4] selftests/damon/_damon_sysfs: support obsolete_target file

[SeongJae Park <sj@kernel.org>]

A DAMON sysfs file, namely obsolete_target, has newly introduced.  Add a
support of that file to _damon_sysfs.py so that DAMON selftests for the
file can be easily written.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 tools/testing/selftests/damon/_damon_sysfs.py | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/damon/_damon_sysfs.py b/tools/testing/selftests/damon/_damon_sysfs.py
index a0e6290833fb..748778b563cd 100644
--- a/tools/testing/selftests/damon/_damon_sysfs.py
+++ b/tools/testing/selftests/damon/_damon_sysfs.py
@@ -475,12 +475,14 @@ class Damos:
 
 class DamonTarget:
     pid = None
+    obsolete = None
     # todo: Support target regions if test is made
     idx = None
     context = None
 
-    def __init__(self, pid):
+    def __init__(self, pid, obsolete=False):
         self.pid = pid
+        self.obsolete = obsolete
 
     def sysfs_dir(self):
         return os.path.join(
@@ -491,8 +493,13 @@ class DamonTarget:
                 os.path.join(self.sysfs_dir(), 'regions', 'nr_regions'), '0')
         if err is not None:
             return err
-        return write_file(
+        err = write_file(
                 os.path.join(self.sysfs_dir(), 'pid_target'), self.pid)
+        if err is not None:
+            return err
+        return write_file(
+                os.path.join(self.sysfs_dir(), 'obsolete_target'),
+                'Y' if self.obsolete else 'N')
 
 class IntervalsGoal:
     access_bp = None
-- 
2.47.3