Re: [ndctl PATCH] cxl/test: use max_available_extent in cxl-destroy-region

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

On Wed, 2024-03-27 at 11:46 -0700, alison.schofield@intel.com wrote:
> From: Alison Schofield <alison.schofield@intel.com>
> 
> Using .size in decoder selection can lead to a set_size failure with
> these error messages:
> 
> cxl region: create_region: region8: set_size failed: Numerical result out of range
> 
> [] cxl_core:alloc_hpa:555: cxl region8: HPA allocation error (-34) for size:0x0000000020000000 in CXL Window 0 [mem 0xf010000000-0xf04fffffff flags 0x200]
> 
> Use max_available_extent for decoder selection instead.
> 
> The test overlooked the region creation failure because it used a
> not 'null' comparison which always succeeds. Use the ! comparator
> after create-region and for the ramsize check so that the test fails
> or continues as expected.
> 
> Signed-off-by: Alison Schofield <alison.schofield@intel.com>
> ---
>  test/cxl-destroy-region.sh | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/test/cxl-destroy-region.sh b/test/cxl-destroy-region.sh
> index cf0a46d6ba58..167fcc4a7ff9 100644
> --- a/test/cxl-destroy-region.sh
> +++ b/test/cxl-destroy-region.sh
> @@ -22,7 +22,7 @@ check_destroy_ram()
>  	decoder=$2
>  
>  	region="$("$CXL" create-region -d "$decoder" -m "$mem" | jq -r ".region")"
> -	if [ "$region" == "null" ]; then
> +	if [[ ! $region ]]; then
>  		err "$LINENO"
>  	fi
>  	"$CXL" enable-region "$region"
> @@ -38,7 +38,7 @@ check_destroy_devdax()
>  	decoder=$2
>  
>  	region="$("$CXL" create-region -d "$decoder" -m "$mem" | jq -r ".region")"
> -	if [ "$region" == "null" ]; then
> +	if [[ ! $region ]]; then

While these ! $region changes are correct (because cxl create-region)
doesn't output any json if creation fails)..

>  		err "$LINENO"
>  	fi
>  	"$CXL" enable-region "$region"
> @@ -55,14 +55,14 @@ check_destroy_devdax()
>  readarray -t mems < <("$CXL" list -b "$CXL_TEST_BUS" -M | jq -r '.[].memdev')
>  for mem in "${mems[@]}"; do
>          ramsize="$("$CXL" list -m "$mem" | jq -r '.[].ram_size')"
> -        if [[ $ramsize == "null" ]]; then
> +        if [[ ! $ramsize ]]; then

.. I think this check needs to check for both empty and "null" - a
memdev that doesn't have ram_size but otherwise emits valid json will
result in "null" here. e.g.:

  $ echo "" | jq -r ".region"

  $ echo "{ }" | jq -r ".region"
  null

So this probably wants to be:

  if [[ $ramsize == "null" || ! $ram_size ]]; then
  ...


>                  continue
>          fi
>          decoder="$("$CXL" list -b "$CXL_TEST_BUS" -D -d root -m "$mem" |
>                    jq -r ".[] |
>                    select(.volatile_capable == true) |
>                    select(.nr_targets == 1) |
> -                  select(.size >= ${ramsize}) |
> +                  select(.max_available_extent >= ${ramsize}) |
>                    .decoder")"
>          if [[ $decoder ]]; then
>  		check_destroy_ram "$mem" "$decoder"
> 
> base-commit: e0d0680bd3e554bd5f211e989480c5a13a023b2d