[NDCTL PATCH v7 4/4] ndctl: add test for qos_class in CXL test suite

[Dave Jiang <dave.jiang@intel.com>]

Add tests in cxl-qos-class.sh to verify qos_class are set with the fake
qos_class create by the kernel.  Root decoders should have qos_class
attribute set. Memory devices should have ram_qos_class or pmem_qos_class
set depending on which partitions are valid.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
v7:
- Add create_region -Q testing (Vishal)
---
 test/common           |   4 ++
 test/cxl-qos-class.sh | 102 ++++++++++++++++++++++++++++++++++++++++++
 test/meson.build      |   2 +
 3 files changed, 108 insertions(+)
 create mode 100755 test/cxl-qos-class.sh

diff --git a/test/common b/test/common
index f1023ef20f7e..5694820c7adc 100644
--- a/test/common
+++ b/test/common
@@ -150,3 +150,7 @@ check_dmesg()
 	grep -q "Call Trace" <<< $log && err $1
 	true
 }
+
+
+# CXL COMMON
+TEST_QOS_CLASS=42
diff --git a/test/cxl-qos-class.sh b/test/cxl-qos-class.sh
new file mode 100755
index 000000000000..145df6134685
--- /dev/null
+++ b/test/cxl-qos-class.sh
@@ -0,0 +1,102 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2024 Intel Corporation. All rights reserved.
+
+. $(dirname $0)/common
+
+rc=77
+
+set -ex
+
+trap 'err $LINENO' ERR
+
+check_prereq "jq"
+
+modprobe -r cxl_test
+modprobe cxl_test
+rc=1
+
+check_qos_decoders () {
+	# check root decoders have expected fake qos_class
+	# also make sure the number of root decoders equal to the number
+	# with qos_class found
+	json=$($CXL list -b cxl_test -D -d root)
+	decoders=$(echo "$json" | jq length)
+	count=0
+	while read -r qos_class
+	do
+		((qos_class == TEST_QOS_CLASS)) || err "$LINENO"
+		count=$((count+1))
+	done <<< "$(echo "$json" | jq -r '.[] | .qos_class')"
+
+	((count == decoders)) || err "$LINENO";
+}
+
+check_qos_memdevs () {
+	# Check that memdevs that expose ram_qos_class or pmem_qos_class have
+	# expected fake value programmed.
+	json=$(cxl list -b cxl_test -M)
+	readarray -t lines < <(jq ".[] | .ram_size, .pmem_size, .ram_qos_class, .pmem_qos_class" <<<"$json")
+	for (( i = 0; i < ${#lines[@]}; i += 4 ))
+	do
+		ram_size=${lines[i]}
+		pmem_size=${lines[i+1]}
+		ram_qos_class=${lines[i+2]}
+		pmem_qos_class=${lines[i+3]}
+
+		if [[ "$ram_size" != null ]]
+		then
+			((ram_qos_class == TEST_QOS_CLASS)) || err "$LINENO"
+		fi
+		if [[ "$pmem_size" != null ]]
+		then
+			((pmem_qos_class == TEST_QOS_CLASS)) || err "$LINENO"
+		fi
+	done
+}
+
+# Based on cxl-create-region.sh create_single()
+destroy_regions()
+{
+	if [[ "$*" ]]; then
+		$CXL destroy-region -f -b cxl_test "$@"
+	else
+		$CXL destroy-region -f -b cxl_test all
+	fi
+}
+
+create_region_check_qos()
+{
+	# the 5th cxl_test decoder is expected to target a single-port
+	# host-bridge. Older cxl_test implementations may not define it,
+	# so skip the test in that case.
+	decoder=$($CXL list -b cxl_test -D -d root |
+		  jq -r ".[4] |
+		  select(.pmem_capable == true) |
+		  select(.nr_targets == 1) |
+		  .decoder")
+
+        if [[ ! $decoder ]]; then
+                echo "no single-port host-bridge decoder found, skipping"
+                return
+        fi
+
+	# Send create-region with -Q to enforce qos_class matching
+	region=$($CXL create-region -Q -d "$decoder" | jq -r ".region")
+	if [[ ! $region ]]; then
+		echo "failed to create single-port host-bridge region"
+		err "$LINENO"
+	fi
+
+	destroy_regions "$region"
+}
+
+check_qos_decoders
+
+check_qos_memdevs
+
+create_region_check_qos
+
+check_dmesg "$LINEO"
+
+modprobe -r cxl_test
diff --git a/test/meson.build b/test/meson.build
index 5eb35749a95b..4892df11119f 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -160,6 +160,7 @@ cxl_events = find_program('cxl-events.sh')
 cxl_poison = find_program('cxl-poison.sh')
 cxl_sanitize = find_program('cxl-sanitize.sh')
 cxl_destroy_region = find_program('cxl-destroy-region.sh')
+cxl_qos_class = find_program('cxl-qos-class.sh')
 
 tests = [
   [ 'libndctl',               libndctl,		  'ndctl' ],
@@ -192,6 +193,7 @@ tests = [
   [ 'cxl-poison.sh',          cxl_poison,         'cxl'   ],
   [ 'cxl-sanitize.sh',        cxl_sanitize,       'cxl'   ],
   [ 'cxl-destroy-region.sh',  cxl_destroy_region, 'cxl'   ],
+  [ 'cxl-qos-class.sh',       cxl_qos_class,      'cxl'   ],
 ]
 
 if get_option('destructive').enabled()
-- 
2.43.0