Re: [PATCH-next 5/6] selftests/cgroup: Check for a single range nohz_full CPUs before running test matrix

[Guopeng Zhang]

在 2026/10/22 11:16, Waiman Long 写道:
> Commit 989ca25c10ca ("selftests/cgroup: Add tests for nohz_full
> housekeeping check") adds a nohz_full test matrix that will only be run
> when a nohz_full boot parameter cover all the CPUs beyond CPUs 0-7. The
> code looks for the first and last CPU numbers in the nohz_full sysfs
> file to determine if that criterion is met. However if there are holes in
> the range (i.e. has ",") the test matrix may be incorrectly run leading
> to unexpected test failure. Fix that by skipping "," and anything after
> that to make sure the first range will cover all the remaining CPUs.
> 
> Fixes: 989ca25c10ca ("selftests/cgroup: Add tests for nohz_full housekeeping check")
> Signed-off-by: Waiman Long <longman@xxxxxxxxxx>
> ---
>  tools/testing/selftests/cgroup/test_cpuset_prs.sh | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/testing/selftests/cgroup/test_cpuset_prs.sh b/tools/testing/selftests/cgroup/test_cpuset_prs.sh
> index 8595b6b4b7bf..5bc144836bdf 100755
> --- a/tools/testing/selftests/cgroup/test_cpuset_prs.sh
> +++ b/tools/testing/selftests/cgroup/test_cpuset_prs.sh
> @@ -111,9 +111,9 @@ echo "" > test/cpuset.cpus
>  #
>  # If nohz_full CPUs have been reserved at boot time, they should not include
>  # CPUs 0-7 as that may fail some of the test cases. On the other hand if the
> -# set of nohz_full CPUs includes all the CPUs except 0-7, we can run a special
> -# set of housekeeping CPUs exhaustion tests to see if the cpuset code will
> -# reject them.
> +# set of nohz_full CPUs includes all the CPUs except 0-7 in a single range
> +# <first>-<last>, we can run a special set of housekeeping CPUs exhaustion
> +# tests to see if the cpuset code will reject them.
>  #
>  FIRST_NOHZ_FULL_CPU=
>  LAST_NOHZ_FULL_CPU=
> @@ -124,7 +124,7 @@ NOHZ_FULL_CPUS=
>  LAST_PRESENT_CPU=$(cat /sys/devices/system/cpu/present | sed -e "s/.*[,-]//")
>  [[ -n "$NOHZ_FULL_CPUS" ]] && {
>  	FIRST_NOHZ_FULL_CPU=$(echo $NOHZ_FULL_CPUS | sed -e "s/[,-].*//")
> -	LAST_NOHZ_FULL_CPU=$(echo $NOHZ_FULL_CPUS | sed -e "s/.*[,-]//")
> +	LAST_NOHZ_FULL_CPU=$(echo $NOHZ_FULL_CPUS | sed -e "s/,.*//;s/.*[-]//")
>  	echo "Boot nohz_full CPUs: $NOHZ_FULL_CPUS"
>  }
>  [[ -n "$FIRST_NOHZ_FULL_CPU" && "$FIRST_NOHZ_FULL_CPU" -le 7 ]] &&

Reviewed-by: Guopeng Zhang <zhangguopeng@xxxxxxxxxx>
Tested-by: Guopeng Zhang <zhangguopeng@xxxxxxxxxx>