Revert "Reapply "Migrate the blkio controller to the v2 cgroup hierarchy""

This reverts commit d71f9e5fbbbc1b4a0f910c2c7606915bfeae68a4.

Reason for revert: p0 failed test (b/308687042)

Change-Id: I3d8cb899d79634bb1c80f7d05af5c1311358c25c
diff --git a/libprocessgroup/profiles/cgroups.json b/libprocessgroup/profiles/cgroups.json
index d013ec8..3e4393d 100644
--- a/libprocessgroup/profiles/cgroups.json
+++ b/libprocessgroup/profiles/cgroups.json
@@ -1,6 +1,13 @@
 {
   "Cgroups": [
     {
+      "Controller": "blkio",
+      "Path": "/dev/blkio",
+      "Mode": "0775",
+      "UID": "system",
+      "GID": "system"
+    },
+    {
       "Controller": "cpu",
       "Path": "/dev/cpuctl",
       "Mode": "0755",
@@ -32,12 +39,6 @@
       {
         "Controller": "freezer",
         "Path": "."
-      },
-      {
-        "Controller": "io",
-        "Path": ".",
-        "NeedsActivation": true,
-        "Optional": true
       }
     ]
   }
diff --git a/libprocessgroup/profiles/task_profiles.json b/libprocessgroup/profiles/task_profiles.json
index 6314667..1fc66ba 100644
--- a/libprocessgroup/profiles/task_profiles.json
+++ b/libprocessgroup/profiles/task_profiles.json
@@ -442,7 +442,8 @@
           "Name": "JoinCgroup",
           "Params":
           {
-            "Controller": "io"
+            "Controller": "blkio",
+            "Path": "background"
           }
         }
       ]
@@ -454,7 +455,8 @@
           "Name": "JoinCgroup",
           "Params":
           {
-            "Controller": "io"
+            "Controller": "blkio",
+            "Path": ""
           }
         }
       ]
@@ -466,7 +468,8 @@
           "Name": "JoinCgroup",
           "Params":
           {
-            "Controller": "io"
+            "Controller": "blkio",
+            "Path": ""
           }
         }
       ]
@@ -478,7 +481,8 @@
           "Name": "JoinCgroup",
           "Params":
           {
-            "Controller": "io"
+            "Controller": "blkio",
+            "Path": ""
           }
         }
       ]
diff --git a/rootdir/init.rc b/rootdir/init.rc
index fb64736..317f809 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -219,6 +219,26 @@
     write /dev/stune/nnapi-hal/schedtune.boost 1
     write /dev/stune/nnapi-hal/schedtune.prefer_idle 1
 
+    # Create blkio group and apply initial settings.
+    # This feature needs kernel to support it, and the
+    # device's init.rc must actually set the correct values.
+    mkdir /dev/blkio/background
+    chown system system /dev/blkio
+    chown system system /dev/blkio/background
+    chown system system /dev/blkio/tasks
+    chown system system /dev/blkio/background/tasks
+    chown system system /dev/blkio/cgroup.procs
+    chown system system /dev/blkio/background/cgroup.procs
+    chmod 0664 /dev/blkio/tasks
+    chmod 0664 /dev/blkio/background/tasks
+    chmod 0664 /dev/blkio/cgroup.procs
+    chmod 0664 /dev/blkio/background/cgroup.procs
+    write /dev/blkio/blkio.weight 1000
+    write /dev/blkio/background/blkio.weight 200
+    write /dev/blkio/background/blkio.bfq.weight 10
+    write /dev/blkio/blkio.group_idle 0
+    write /dev/blkio/background/blkio.group_idle 0
+
     restorecon_recursive /mnt
 
     mount configfs none /config nodev noexec nosuid