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

["Verma, Vishal L" <vishal.l.verma@intel.com>]

On Thu, 2024-02-08 at 13:11 -0700, Dave Jiang wrote:
> 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

For consistency, the script based tests all have the while..do,
for..do, if..then bits on the same line. Would be nice not to break
that precedent.

> +		((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]}

Hm instead of splitting into lines, and then looping through them, why
not just invoke jq for each?

ram_size=$(jq ".[] | .ram_size" <<< $json)
pmem_size=$(jq ".[] | .pmem_size" <<< $json)
...etc

> +
> +		if [[ "$ram_size" != null ]]
> +		then
> +			((ram_qos_class == TEST_QOS_CLASS)) || err "$LINENO"
> +		fi

This might be a bit more readable as:

if [[ "$ram_size" != null ]] && ((ram_qos_class != TEST_QOS_CLASS)); then
	err "$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()