From be8b87d5592187f692ba22318a2aff8cfc45d065 Mon Sep 17 00:00:00 2001
From: Valentin Schneider <valentin.schneider@arm.com>
Date: Mon, 18 Mar 2019 16:21:50 +0000
Subject: [PATCH] module/sched: Fix/simplify procfs packing behaviour

Back when I first wrote this I tried to make something smart that
would automatically detect which procfs entries to pack into a
mapping, the condition to do so being "the entry ends with a
digit and there is another entry with the same name but a different
digit".

I wrongly assumed this would always work for the sched_domain entries,
but it's possible to have a domain with a single group and thus a
single "group0" entry.

Since we know which entries we want to pack, let's hard-code these and
be less smart about it.
---
 devlib/module/sched.py | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/devlib/module/sched.py b/devlib/module/sched.py
index 63125fc..ce99d6d 100644
--- a/devlib/module/sched.py
+++ b/devlib/module/sched.py
@@ -52,6 +52,12 @@ class SchedProcFSNode(object):
 
     _re_procfs_node = re.compile(r"(?P<name>.*\D)(?P<digits>\d+)$")
 
+    PACKABLE_ENTRIES = [
+        "cpu",
+        "domain",
+        "group"
+    ]
+
     @staticmethod
     def _ends_with_digits(node):
         if not isinstance(node, basestring):
@@ -71,18 +77,19 @@ class SchedProcFSNode(object):
         """
         :returns: The name of the procfs node
         """
-        return re.search(SchedProcFSNode._re_procfs_node, node).group("name")
+        match = re.search(SchedProcFSNode._re_procfs_node, node)
+        if match:
+            return match.group("name")
 
-    @staticmethod
-    def _packable(node, entries):
+        return node
+
+    @classmethod
+    def _packable(cls, node):
         """
         :returns: Whether it makes sense to pack a node into a common entry
         """
         return (SchedProcFSNode._ends_with_digits(node) and
-                any([SchedProcFSNode._ends_with_digits(x) and
-                     SchedProcFSNode._node_digits(x) != SchedProcFSNode._node_digits(node) and
-                     SchedProcFSNode._node_name(x) == SchedProcFSNode._node_name(node)
-                     for x in entries]))
+                SchedProcFSNode._node_name(node) in cls.PACKABLE_ENTRIES)
 
     @staticmethod
     def _build_directory(node_name, node_data):
@@ -119,7 +126,7 @@ class SchedProcFSNode(object):
         # Find which entries can be packed into a common entry
         packables = {
             node : SchedProcFSNode._node_name(node) + "s"
-            for node in list(nodes.keys()) if SchedProcFSNode._packable(node, list(nodes.keys()))
+            for node in list(nodes.keys()) if SchedProcFSNode._packable(node)
         }
 
         self._dyn_attrs = {}