>From 0edbc6d9f7abae299d6b1bd4b8ad76728afab313 Mon Sep 17 00:00:00 2001
Message-Id: <0edbc6d9f7abae299d6b1bd4b8ad76728afab313.1508043579.git.shli@fb.com>
From: Shaohua Li <shli@fb.com>
Date: Sat, 14 Oct 2017 18:57:06 -0700
Subject: [PATCH] Add cgroup2 writeback test

---
 common/cgroup2        | 18 +++++++++++++++++
 tests/generic/463     | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/generic/463.out |  2 ++
 tests/generic/group   |  1 +
 4 files changed, 77 insertions(+)
 create mode 100644 common/cgroup2
 create mode 100755 tests/generic/463
 create mode 100644 tests/generic/463.out

diff --git a/common/cgroup2 b/common/cgroup2
new file mode 100644
index 00000000..130c2f79
--- /dev/null
+++ b/common/cgroup2
@@ -0,0 +1,18 @@
+#!/bin/bash
+# cgroup2 specific common functions
+
+export CGROUP2_PATH="/sys/fs/cgroup"
+
+_require_cgroup2()
+{
+	if [ ! -f ${CGROUP2_PATH}/cgroup.subtree_control ]; then
+		_notrun "Test requires cgroup2 enabled"
+	fi
+}
+
+_get_scratch_dev_devt()
+{
+	ls -l $SCRATCH_DEV | awk '{printf("%s:%s", substr($5, 1, length($5)-1), 0)}'
+}
+
+/bin/true
diff --git a/tests/generic/463 b/tests/generic/463
new file mode 100755
index 00000000..8dafadb0
--- /dev/null
+++ b/tests/generic/463
@@ -0,0 +1,56 @@
+#! /bin/bash
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/cgroup2
+
+status=1	# failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+cgname=`mktemp -du ${CGROUP2_PATH}/test.XXXXXX`
+_cleanup()
+{
+    _scratch_unmount
+    cd /
+    rmdir $cgname
+}
+
+# real QA test starts here
+
+# Modify as appropriate.
+_supported_fs generic
+_supported_os Linux
+_require_scratch
+_require_cgroup2
+
+# Setup Filesystem
+_scratch_mkfs >/dev/null 2>&1 \
+        || _fail "mkfs failed"
+
+_scratch_mount \
+        || _fail "mount failed"
+
+echo +io > /sys/fs/cgroup/cgroup.subtree_control
+mkdir $cgname
+
+wbytes=$(
+echo $BASHPID > $cgname/cgroup.procs;
+dd if=/dev/zero of=$SCRATCH_MNT/image bs=1M count=100 >/dev/null 2>&1;
+# Makre sure writeback starts
+sleep 120;
+cat $cgname/io.stat | sed -n "s/$(_get_scratch_dev_devt).*wbytes=\([0-9]*\).*/\1/p"
+)
+
+[ -z "$wbytes" -o "$wbytes" = "0" ] && _fail "Cgroup writeback doesn't work"
+echo "Cgroup writeback test success"
+
+# success, all done
+status=0
+exit
diff --git a/tests/generic/463.out b/tests/generic/463.out
new file mode 100644
index 00000000..211da95e
--- /dev/null
+++ b/tests/generic/463.out
@@ -0,0 +1,2 @@
+QA output created by 463
+Cgroup writeback test success
diff --git a/tests/generic/group b/tests/generic/group
index f2a6cdad..ea7b6956 100644
--- a/tests/generic/group
+++ b/tests/generic/group
@@ -465,3 +465,4 @@
 460 auto quick rw
 461 auto shutdown stress
 462 auto quick dax
+463 cgroup writeback test
-- 
2.11.0