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Date:   Fri, 31 Mar 2023 10:12:09 +0200
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Message-ID: <20230331081209.3170293-1-peternewman@google.com>
Subject: Re: [PATCH v5 3/3] Documentation/x86: Documentation for MON group
 move feature
From:   Peter Newman <peternewman@google.com>
To:     babu.moger@amd.com
Cc:     bp@alien8.de, dave.hansen@linux.intel.com, eranian@google.com,
        fenghua.yu@intel.com, gupasani@google.com, hpa@zytor.com,
        james.morse@arm.com, linux-kernel@vger.kernel.org,
        mingo@redhat.com, peternewman@google.com,
        reinette.chatre@intel.com, skodak@google.com, tglx@linutronix.de,
        tony.luck@intel.com, x86@kernel.org
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Hi Babu,

On Thu, Mar 30, 2023 at 7:33=E2=80=AFPM Moger, Babu <babu.moger@amd.com> wr=
ote:
> On 3/30/23 08:55, Peter Newman wrote:
> > Describe new support for moving MON groups to a new parent CTRL_MON
> > group and its restrictions.
>
> Sorry for coming in late here. I am planning to test these patches. It
> would be helpful to give a simple example to test this feature.

Do you mean inline in the documentation?

For now, you can also try the patch below. These are the testcases I
used.

I'm planning to convert many of our internal, shell script-based test
cases into kernel selftests so I can try to upstream them.

Thanks!
-Peter


---8<-------
From f6d215e90db3c416bd39889b9fa1143d798245e0 Mon Sep 17 00:00:00 2001
From: Peter Newman <peternewman@google.com>
Date: Tue, 7 Mar 2023 11:57:03 +0100
Subject: [PATCH] selftests/resctrl: Test for MON group renaming

Signed-off-by: Peter Newman <peternewman@google.com>
---
 tools/testing/selftests/resctrl/Makefile      |   2 +
 .../selftests/resctrl/test_mongrp_move.sh     | 120 ++++++++++++++++++
 2 files changed, 122 insertions(+)
 create mode 100755 tools/testing/selftests/resctrl/test_mongrp_move.sh

diff --git a/tools/testing/selftests/resctrl/Makefile b/tools/testing/selft=
ests/resctrl/Makefile
index 73d53257df42..0b696e7cf19b 100644
--- a/tools/testing/selftests/resctrl/Makefile
+++ b/tools/testing/selftests/resctrl/Makefile
@@ -5,6 +5,8 @@ CFLAGS +=3D $(KHDR_INCLUDES)
=20
 TEST_GEN_PROGS :=3D resctrl_tests
=20
+TEST_PROGS :=3D test_mongrp_move.sh
+
 include ../lib.mk
=20
 $(OUTPUT)/resctrl_tests: $(wildcard *.c)
diff --git a/tools/testing/selftests/resctrl/test_mongrp_move.sh b/tools/te=
sting/selftests/resctrl/test_mongrp_move.sh
new file mode 100755
index 000000000000..6d9bfc4e0c8d
--- /dev/null
+++ b/tools/testing/selftests/resctrl/test_mongrp_move.sh
@@ -0,0 +1,120 @@
+#!/bin/sh
+
+set -e
+
+rc=3D0
+
+cleanup()
+{
+	rmdir _test_*
+	rmdir mon_groups/_test_*
+}
+
+skip_all()
+{
+	echo Bail out! $1
+
+	cleanup
+
+	# SKIP code is 4.
+	exit 4
+}
+
+expect_success()
+{
+	if [ "$1" -eq 0 ]; then
+		echo ok $2
+	else
+		echo not ok $2
+		rc=3D1
+	fi
+}
+
+expect_fail()
+{
+	if [ "$1" -eq 0 ]; then
+		echo not ok $2
+		rc=3D1
+	else
+		echo ok $2
+	fi
+}
+
+if [ "$(id -u)" !=3D 0 ]; then
+	skip_all "must be run as root"
+fi
+
+if [ ! -d /sys/fs/resctrl/info ]; then
+	mount -t resctrl resctrl /sys/fs/resctrl || skip_all "no resctrlfs"
+fi
+
+cd /sys/fs/resctrl
+
+if [ ! -f info/L3_MON/mon_features ]; then
+	skip_all "no monitoring support"
+fi
+
+if [ ! -f schemata ]; then
+	skip_all "no allocation support"
+fi
+
+echo "1..11"
+
+if [ -d _test_c1 ] || [ -d _test_c2 ] || [ -d mon_groups/_test_m1 ]; then
+	skip_all "test directories already exist"
+fi
+
+mkdir _test_c1
+mkdir _test_c2
+mkdir _test_c3
+
+mkdir mon_groups/_test_m1
+echo 1 > mon_groups/_test_m1/cpus
+
+mkdir _test_c1/mon_groups/_test_m1
+echo $$ > _test_c1/tasks
+echo $$ > _test_c1/mon_groups/_test_m1/tasks
+
+if mv _test_c1/mon_groups/_test_m1 _test_c2/mon_groups; then
+	echo "ok 1 # MON group move to new parent succeeded"
+else
+	echo "1..0 # skip because MON group move to new parent not supported"
+	cleanup
+	exit 4
+fi
+
+set +e
+
+grep -q $$ _test_c2/tasks
+expect_success $? "2 # PID in new CTRL_MON group"
+
+grep -q $$ _test_c2/mon_groups/_test_m1/tasks
+expect_success $? "3 # PID remains in MON group after move"
+
+grep -q $$ _test_c1/tasks
+expect_fail $? "4 # PID no longer in previous CTRL_MON group"
+
+mv _test_c2/mon_groups/_test_m1/cpus mon_groups
+expect_fail $? "5 # moving files not allowed"
+
+mv _test_c2/mon_groups/_test_m1 _test_c2/mon_groups/_test_m2
+expect_success $? "6 # simple MON directory rename"
+
+mv _test_c2/mon_groups/_test_m2 info
+expect_fail $? "7 # move to info not allowed"
+
+mv _test_c2/mon_groups/_test_m2 _test_c2/mon_groups/mon_groups
+expect_fail $? "8 # rename to mon_groups not allowed"
+
+mv mon_groups/_test_m1 _test_c1/mon_groups
+expect_fail $? "9 # cannot move groups monitoring CPUs"
+
+mv mon_groups/_test_m1 mon_groups/_test_m2
+expect_success $? "10 # groups monitoring CPUs can be renamed"
+
+mv mon_groups/_test_m2/mon_data _test_c1/mon_groups
+expect_fail $? "11 # cannot move subdirectories of a mon_group"
+
+cleanup
+
+exit $rc
--=20
2.40.0.423.gd6c402a77b-goog