[LTP] [PATCH] cpuset_hotplug_test/cpuset_hotplug: Fix bug for obtaining task_cpus value in root_cpu_hotplug_test

[Samuel Zou]

Hi Xu,

Please push it directly, thanks a lot :)

On 2021/6/21 17:53, xuyang2018.jy@fujitsu.com wrote:
> Hi Zou
> Do you want to send a v2 patch? Or I modify this patch and push it directly.
> 
> Best Regards
> Yang Xu
>> Hi Xu,
>>
>> You'are right, I miss to get task_cpus value in general_cpu_hotplug_test().
>> Thanks for your review and agree with your modification.
>>
>>
>> On 2021/6/21 16:56, xuyang2018.jy@fujitsu.com wrote:
>>> Hi Zou
>>>
>>> It looks like this patch also miss to get task_cpus value
>>> intgeneric_cpu_hotplug_test when expect cpu value is EMPTY.
>>>
>>> I can reproduce this easily by increasing the possible_cpus value in
>>> cmdline. Merge your patch, this case still fails as below:
>>> cpuset_hotplug 1 TINFO: CPUs are numbered continuously starting at 0
>>> (0-3)
>>> cpuset_hotplug 1 TINFO: Nodes are numbered continuously starting at 0
>>> (0-3)
>>> /opt/ltp/testcases/bin/cpuset_funcs.sh: line 179: 5676 Killed
>>> /bin/cat /dev/zero > /dev/null 2>&1
>>> cpuset_hotplug 1 TPASS: Cpuset vs CPU hotplug test succeeded.
>>> /opt/ltp/testcases/bin/cpuset_funcs.sh: line 179: 5714 Killed
>>> /bin/cat /dev/zero > /dev/null 2>&1
>>> cpuset_hotplug 3 TPASS: Cpuset vs CPU hotplug test succeeded.
>>> /opt/ltp/testcases/bin/cpuset_funcs.sh: line 179: 5750 Killed
>>> /bin/cat /dev/zero > /dev/null 2>&1
>>> cpuset_hotplug 5 TPASS: Cpuset vs CPU hotplug test succeeded.
>>> cpuset_hotplug 7 TFAIL: task's cpu present list isn't expected(Result:
>>> 0-7, Expect: 0-3).
>>> /opt/ltp/testcases/bin/cpuset_funcs.sh: line 179: 5795 Killed
>>> /bin/cat /dev/zero > /dev/null 2>&1
>>> /opt/ltp/testcases/bin/cpuset_funcs.sh: line 179: 5846 Killed
>>> /bin/cat /dev/zero > /dev/null 2>&1
>>> cpuset_hotplug 9 TPASS: Cpuset vs CPU hotplug test succeeded.
>>> /opt/ltp/testcases/bin/cpuset_funcs.sh: line 179: 5894 Killed
>>> /bin/cat /dev/zero > /dev/null 2>&1
>>> cpuset_hotplug 11 TPASS: Cpuset vs CPU hotplug test succeeded.
>>>
>>>
>>> Also since we have use present value, we shoud adjust output to match
>>> it. I modify this patch as below, What do you think about it?
>>>
>>> ---
>>> a/testcases/kernel/controllers/cpuset/cpuset_hotplug_test/cpuset_hotplug_test.sh
>>>
>>> +++
>>> b/testcases/kernel/controllers/cpuset/cpuset_hotplug_test/cpuset_hotplug_test.sh
>>>
>>> @@ -93,9 +93,7 @@ root_cpu_hotplug_test()
>>>
>>> root_cpus="`cat $CPUSET/cpuset.cpus`"
>>>
>>> - task_cpus="`cat /proc/$tst_pid/status | grep Cpus_allowed_list`"
>>> - task_cpus="`echo $task_cpus | sed -e 's/Cpus_allowed_list: //'`"
>>> -
>>> + task_cpus="`cat /sys/devices/system/cpu/present`"
>>> check_result "$root_cpus" "$expect_cpus"
>>> ret=$?
>>> if [ $ret -eq 0 ]
>>> @@ -103,7 +101,7 @@ root_cpu_hotplug_test()
>>> check_result "$task_cpus" "$expect_task_cpus"
>>> ret=$?
>>> if [ $ret -ne 0 ]; then
>>> - tst_resm TFAIL "task's allowed list isn't
>>> expected.(Result: $task_cpus, Expect: $expect_task_cpus)"
>>> + tst_resm TFAIL "task's present list isn't
>>> expected.(Result: $task_cpus, Expect: $expect_task_cpus)"
>>> fi
>>> else
>>> tst_resm TFAIL "root group's cpus isn't
>>> expected(Result: $root_cpus, Expect: $expect_cpus)."
>>> @@ -166,7 +164,6 @@ general_cpu_hotplug_test()
>>> sleep 1
>>>
>>> cpus="`cat $path/cpuset.cpus`"
>>> -
>>> task_cpus="`cat /proc/$tst_pid/status | grep Cpus_allowed_list`"
>>> task_cpus="`echo $task_cpus | sed -e 's/Cpus_allowed_list: //'`"
>>>
>>> @@ -186,6 +183,7 @@ general_cpu_hotplug_test()
>>> /bin/kill -s SIGKILL $tst_pid
>>> return 1
>>> fi
>>> + task_cpus="`cat /sys/devices/system/cpu/present`"
>>> fi
>>>
>>> check_result "$cpus" "$expect_cpus"
>>> @@ -194,7 +192,7 @@ general_cpu_hotplug_test()
>>> check_result $task_cpus $expect_task_cpus
>>> ret=$?
>>> if [ $ret -ne 0 ]; then
>>> - tst_resm TFAIL "task's cpu allowed list isn't
>>> expected(Result: $task_cpus, Expect: $expect_task_cpus)."
>>> + tst_resm TFAIL "task's cpu present list isn't
>>> expected(Result: $task_cpus, Expect: $expect_task_cpus)."
>>> fi
>>> else
>>> if [ "$cpus" = "" ]; then
>>>
>>>
>>> Best Regards
>>> Yang XU
>>>> Hi Samuel, Zou
>>>>> Hi,
>>>>>
>>>>> A friendly reminder for the two patchs in:
>>>>>
>>>>> https://patchwork.ozlabs.org/project/ltp/patch/1617707717-63693-1-git-send-email-zou_wei@huawei.com/
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> https://patchwork.ozlabs.org/project/ltp/patch/1617701249-62196-1-git-send-email-zou_wei@huawei.com/
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> Can someone please review the patchs, comment, and if appropriate
>>>>> commit
>>>>> them?
>>>>>
>>>>> Regards,
>>>>> Zou Wei
>>>>>
>>>>> On 2021/4/6 17:27, Zou Wei wrote:
>>>>>> --------------------------
>>>>>>
>>>>>> 1. The method of obtaining $task_cpus from root_cpu_hotplug_test is
>>>>>> incorrect, because the value of Cpus_allowed_list is related
>>>>>> to /sys/devices/system/cpu/possible and
>>>>>> /sys/devices/system/cpu/isolated.
>>>>>>
>>>>>> 2. If isolcpus is configured in cmdline, the value of
>>>>>> Cpus_allowed_list is equal to /sys/devices/system/cpu/possible minus
>>>>>> /sys/devices/system/cpu/isolated. In this case, $task_cpus is
>>>>>> inconsistent
>>>>>> with $expect_task_cpus, test will be failed.
>>>>>>
>>>>>> 3. Need to change the method of obtaining $task_cpu
>>>>>> from /sys/devices/system/cpu/present.
>>>> Thanks for your patch, I also met the same problem when
>>>> /sys/devices/system/cpu/possible is not equal
>>>> to/sys/devices/system/cpu/possible/present .
>>>> Cpus_allowed_list: 0-511
>>>> but my present cpu is 0-103
>>>>
>>>> Then I use possible_cpus==104 in /etc/defaut/grub, cpu_hotplug case then
>>>> pass.
>>>>
>>>> According to kernel documentation[1] and kernel fs/proc/array code[2](It
>>>> just print cpu mask instead of present cpu), So using
>>>> /sys/devices/system/cpu/present is right instead of getting
>>>> cpu_allow_list.
>>>>
>>>> possible: cpus that have been allocated resources and can be
>>>> brought online if they are present.
>>>>
>>>> present: cpus that have been identified as being present in
>>>> the system.
>>>>
>>>>
>>>> Reviewed-by: Yang Xu <xuyang2018.jy@fujitsu.com>
>>>>
>>>> [1]https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/ABI/testing/sysfs-devices-system-cpu
>>>>
>>>>
>>>> [2]https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/fs/proc/array.c#n418
>>>>
>>>>
>>>>
>>>> ps:
>>>> Also find a kernel documentation problem and have sent a patch to remove
>>>> non-existed cpu-hotplug.txt in admin-guide/cputopology.rst.
>>>>
>>>>
>>>> Best Regards
>>>> Yang Xu
>>>>>>
>>>>>> 4. The description of cpu_present_mask:
>>>>>> Bitmap of CPUs currently present in the system.
>>>>>> Not all of them may be online. When physical hotplug is processed
>>>>>> by the relevant subsystem (e.g ACPI) can change and new bit either be
>>>>>> added or removed from the map depending on the event is
>>>>>> hot-add/hot-remove. There are currently no locking rules as of now.
>>>>>> Typical usage is to init topology during boot,
>>>>>> at which time hotplug is disabled.
>>>>>>
>>>>>> Signed-off-by: Zou Wei <zou_wei@huawei.com>
>>>>>> ---
>>>>>> .../controllers/cpuset/cpuset_hotplug_test/cpuset_hotplug_test.sh | 3
>>>>>> +--
>>>>>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>>>>>
>>>>>> diff --git
>>>>>> a/testcases/kernel/controllers/cpuset/cpuset_hotplug_test/cpuset_hotplug_test.sh
>>>>>>
>>>>>>
>>>>>> b/testcases/kernel/controllers/cpuset/cpuset_hotplug_test/cpuset_hotplug_test.sh
>>>>>>
>>>>>>
>>>>>>
>>>>>> index 155e536..2c6993a 100755
>>>>>> ---
>>>>>> a/testcases/kernel/controllers/cpuset/cpuset_hotplug_test/cpuset_hotplug_test.sh
>>>>>>
>>>>>>
>>>>>>
>>>>>> +++
>>>>>> b/testcases/kernel/controllers/cpuset/cpuset_hotplug_test/cpuset_hotplug_test.sh
>>>>>>
>>>>>>
>>>>>>
>>>>>> @@ -93,8 +93,7 @@ root_cpu_hotplug_test()
>>>>>> root_cpus="`cat $CPUSET/cpuset.cpus`"
>>>>>> - task_cpus="`cat /proc/$tst_pid/status | grep Cpus_allowed_list`"
>>>>>> - task_cpus="`echo $task_cpus | sed -e 's/Cpus_allowed_list: //'`"
>>>>>> + task_cpus="`cat /sys/devices/system/cpu/present`"
>>>>>> check_result "$root_cpus" "$expect_cpus"
>>>>>> ret=$?
>>>>>>
>>>>>