[LTP] [PATCH] runpwtests03: use expr to calculate total_cpus for runpwtests03

[Xiao Yang]

Hi,

Don't need.  It's fine to me as well.

Pushed, thanks for your patch.

Best Reagrds,

Xiao Yang

On 06/26/2019 11:45 AM, Po-Hsu Lin wrote:
> Thanks for the review,
>
> They are both fine with me, if you want to see this to be changed into
> the double parentheses form, I can send a V2 for that.
>
> Cheers
> PHLin
>
> On Wed, Jun 26, 2019 at 10:55 AM Xiao Yang <ice_yangxiao@163.com> wrote:
>> Hi,
>>
>> Sorry, I missed the fact that tst_ncpus is executable binary.
>>
>> It's good to me.
>>
>> Reviewed-by: Xiao Yang <ice_yangxiao@163.com>
>>
>> BTW: if you don't want to depend expr command, we can fix it by using
>> total_cpus=$((total_cpus - 1)) instead.
>>
>> Best Regards,
>> Xiao Yang
>>
>> On 06/26/2019 12:13 AM, Po-Hsu Lin wrote:
>>> Hello!
>>>
>>> The $() here is for the tst_ncpus executable, which will return the
>>> total cpu number.
>>>
>>> Thanks
>>> PHLin
>>>
>>> On Tue, Jun 25, 2019 at 6:59 PM Xiao Yang <yangx.jy@cn.fujitsu.com> wrote:
>>>> On 2019/06/25 18:03, Po-Hsu Lin wrote:
>>>>> The arithmetic operation (( total_cpus-=1 )) does not work for dash,
>>>>> which was symbolic linked to /bin/sh on some OS like Ubuntu.
>>>>>
>>>>> In such case, people will see error like:
>>>>>      runpwtests03.sh: total_cpus-=1: not found
>>>>>
>>>>> And this further leads to access for a non-existing file and cause
>>>>> false-positive result in the end:
>>>>>      runpwtests03.sh: cannot create
>>>>>      /sys/devices/system/cpu/cpu8/cpufreq/scaling_governor: Directory nonexistent
>>>>>      runpwtests03.sh: FAIL: Unable to set governor -- powersave for cpu8
>>>>>      Power_Management03 2 TFAIL: Changing governors
>>>>>
>>>>> Use expr instead for fix this issue.
>>>>>
>>>>> Signed-off-by: Po-Hsu Lin<po-hsu.lin@canonical.com>
>>>>> ---
>>>>>     testcases/kernel/power_management/runpwtests03.sh | 9 +++------
>>>>>     1 file changed, 3 insertions(+), 6 deletions(-)
>>>>>
>>>>> diff --git a/testcases/kernel/power_management/runpwtests03.sh b/testcases/kernel/power_management/runpwtests03.sh
>>>>> index 11197937f..3fb85d273 100755
>>>>> --- a/testcases/kernel/power_management/runpwtests03.sh
>>>>> +++ b/testcases/kernel/power_management/runpwtests03.sh
>>>>> @@ -25,8 +25,7 @@ export TST_TOTAL=4
>>>>>     . pm_include.sh
>>>>>
>>>>>     check_cpufreq_sysfs_files() {
>>>>> -     total_cpus=$(tst_ncpus)
>>>>> -     (( total_cpus-=1 ))
>>>>> +     total_cpus=`expr $(tst_ncpus) - 1`
>>>> Hi,
>>>>
>>>> It's wrong for single variable to use $(), did you mean ${tst_ncpus}?
>>>>
>>>> Best Regards,
>>>> Xiao Yang
>>>>>         RC=0
>>>>>
>>>>>         for cpu in $(seq 0 "${total_cpus}" )
>>>>> @@ -51,8 +50,7 @@ check_cpufreq_sysfs_files() {
>>>>>     change_govr() {
>>>>>         available_govr=$(get_supporting_govr)
>>>>>
>>>>> -     total_cpus=$(tst_ncpus)
>>>>> -     (( total_cpus-=1 ))
>>>>> +     total_cpus=`expr $(tst_ncpus) - 1`
>>>>>         RC=0
>>>>>
>>>>>         for cpu in $(seq 0 "${total_cpus}" )
>>>>> @@ -79,8 +77,7 @@ change_freq() {
>>>>>         available_govr=$(get_supporting_govr)
>>>>>         RC=0
>>>>>
>>>>> -     total_cpus=$(tst_ncpus)
>>>>> -     (( total_cpus-=1 ))
>>>>> +     total_cpus=`expr $(tst_ncpus) - 1`
>>>>>
>>>>>         if ( echo ${available_govr} | grep -i "userspace" \
>>>>>                 >/dev/null 2>&1 ); then
>>>>