* [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups on kernel > 3.4.0
@ 2015-01-19 8:36 Li Jinyue
2015-01-26 15:22 ` Cyril Hrubis
2015-01-28 8:23 ` [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads " Wanlong Gao
0 siblings, 2 replies; 7+ messages in thread
From: Li Jinyue @ 2015-01-19 8:36 UTC (permalink / raw)
To: ltp-list; +Cc: dingguofu, zhanyongming
For kernel commit c4c27fbdda4e8ba87806c415b6d15266b07bce4b,
disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups.
So, we kindly avoid to attach these threads in cgroup tests.
Signed-off-by: Li Jinyue <lijinyue@huawei.com>
---
testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
index 30476bd..30fffb6 100755
--- a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
+++ b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
@@ -186,6 +186,16 @@ case $attach_operation in
do
cur_pid=`sed -n "$i""p" $TMPFILE`
if [ -e /proc/$cur_pid/ ];then
+ #For kernel 3.4.0 and higher,kernel disallow attaching kthreadd or
+ #PF_THREAD_BOUND threads to cgroups.
+ #kernel commit: c4c27fbdda4e8ba87806c415b6d15266b07bce4b
+ tst_kvercmp 3 4 0
+ if [ $? -ne 0 ]; then
+ thread_flag=`cat /proc/$cur_pid/stat | awk '{print $9}'`
+ if [ $cur_pid -eq 2 -o $((${thread_flag}&0x04000000)) -eq 67108864 ];then
+ continue
+ fi
+ fi
do_echo 1 1 "$cur_pid" /dev/cgroup/subgroup_1/tasks
fi
done
--
1.8.2.2
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^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups on kernel > 3.4.0
2015-01-19 8:36 [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups on kernel > 3.4.0 Li Jinyue
@ 2015-01-26 15:22 ` Cyril Hrubis
[not found] ` <54C9DCBE.9010609@huawei.com>
2015-01-28 8:23 ` [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads " Wanlong Gao
1 sibling, 1 reply; 7+ messages in thread
From: Cyril Hrubis @ 2015-01-26 15:22 UTC (permalink / raw)
To: Li Jinyue; +Cc: ltp-list, dingguofu, zhanyongming
Hi!
> For kernel commit c4c27fbdda4e8ba87806c415b6d15266b07bce4b,
> disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups.
>
> So, we kindly avoid to attach these threads in cgroup tests.
What happens when we try that out? Can you include the error message (if
any)?
> Signed-off-by: Li Jinyue <lijinyue@huawei.com>
> ---
> testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
> index 30476bd..30fffb6 100755
> --- a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
> +++ b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
> @@ -186,6 +186,16 @@ case $attach_operation in
> do
> cur_pid=`sed -n "$i""p" $TMPFILE`
> if [ -e /proc/$cur_pid/ ];then
> + #For kernel 3.4.0 and higher,kernel disallow attaching kthreadd or
> + #PF_THREAD_BOUND threads to cgroups.
> + #kernel commit: c4c27fbdda4e8ba87806c415b6d15266b07bce4b
> + tst_kvercmp 3 4 0
> + if [ $? -ne 0 ]; then
> + thread_flag=`cat /proc/$cur_pid/stat | awk '{print $9}'`
Why not just thread_flag=$(awk '{print $9}'/proc/$cur_pid/stat) ?
> + if [ $cur_pid -eq 2 -o $((${thread_flag}&0x04000000)) -eq 67108864 ];then
So you are relying on fact that kthreadadd pid is 2. Is that specified
somewhere? I doubt that this will hold forever.
Also the magical constant 67108864 is very cryptic, what about using
-ne 0 instead -eq 67108864?
--
Cyril Hrubis
chrubis@suse.cz
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^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups on kernel > 3.4.0
2015-01-19 8:36 [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups on kernel > 3.4.0 Li Jinyue
2015-01-26 15:22 ` Cyril Hrubis
@ 2015-01-28 8:23 ` Wanlong Gao
2015-01-28 8:49 ` Lijinyue
1 sibling, 1 reply; 7+ messages in thread
From: Wanlong Gao @ 2015-01-28 8:23 UTC (permalink / raw)
To: Li Jinyue; +Cc: ltp-list, dingguofu, zhanyongming
On 01/19/2015 04:36 PM, Li Jinyue wrote:
> For kernel commit c4c27fbdda4e8ba87806c415b6d15266b07bce4b,
> disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups.
>
> So, we kindly avoid to attach these threads in cgroup tests.
>
> Signed-off-by: Li Jinyue <lijinyue@huawei.com>
> ---
> testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
> index 30476bd..30fffb6 100755
> --- a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
> +++ b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
> @@ -186,6 +186,16 @@ case $attach_operation in
> do
> cur_pid=`sed -n "$i""p" $TMPFILE`
> if [ -e /proc/$cur_pid/ ];then
> + #For kernel 3.4.0 and higher,kernel disallow attaching kthreadd or
> + #PF_THREAD_BOUND threads to cgroups.
I check the current kernel and find that this flag already removed now, please check the following
commit:
commit 14a40ffccd6163bbcd1d6f32b28a88ffe6149fc6
Author: Tejun Heo <tj@kernel.org>
Date: Tue Mar 19 13:45:20 2013 -0700
sched: replace PF_THREAD_BOUND with PF_NO_SETAFFINITY
PF_THREAD_BOUND was originally used to mark kernel threads which were
bound to a specific CPU using kthread_bind() and a task with the flag
set allows cpus_allowed modifications only to itself. Workqueue is
currently abusing it to prevent userland from meddling with
cpus_allowed of workqueue workers.
> + #kernel commit: c4c27fbdda4e8ba87806c415b6d15266b07bce4b
> + tst_kvercmp 3 4 0
> + if [ $? -ne 0 ]; then
And where to go if tst_kvercmp failed and return -1?
> + thread_flag=`cat /proc/$cur_pid/stat | awk '{print $9}'`
> + if [ $cur_pid -eq 2 -o $((${thread_flag}&0x04000000)) -eq 67108864 ];then
These magic numbers must at least be commented to be understand easily.
Thanks,
Wanlong Gao
> + continue
> + fi
> + fi
> do_echo 1 1 "$cur_pid" /dev/cgroup/subgroup_1/tasks
> fi
> done
>
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^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups on kernel > 3.4.0
2015-01-28 8:23 ` [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads " Wanlong Gao
@ 2015-01-28 8:49 ` Lijinyue
2015-01-28 9:07 ` Wanlong Gao
0 siblings, 1 reply; 7+ messages in thread
From: Lijinyue @ 2015-01-28 8:49 UTC (permalink / raw)
To: gaowanlong; +Cc: ltp-list, dingguofu, zhanyongming
On 2015/1/28 16:23, Wanlong Gao wrote:
> On 01/19/2015 04:36 PM, Li Jinyue wrote:
>> For kernel commit c4c27fbdda4e8ba87806c415b6d15266b07bce4b,
>> disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups.
>>
>> So, we kindly avoid to attach these threads in cgroup tests.
>>
>> Signed-off-by: Li Jinyue <lijinyue@huawei.com>
>> ---
>> testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh | 10 ++++++++++
>> 1 file changed, 10 insertions(+)
>>
>> diff --git a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
>> index 30476bd..30fffb6 100755
>> --- a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
>> +++ b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
>> @@ -186,6 +186,16 @@ case $attach_operation in
>> do
>> cur_pid=`sed -n "$i""p" $TMPFILE`
>> if [ -e /proc/$cur_pid/ ];then
>> + #For kernel 3.4.0 and higher,kernel disallow attaching kthreadd or
>> + #PF_THREAD_BOUND threads to cgroups.
>
> I check the current kernel and find that this flag already removed now, please check the following
> commit:
>
> commit 14a40ffccd6163bbcd1d6f32b28a88ffe6149fc6
> Author: Tejun Heo <tj@kernel.org>
> Date: Tue Mar 19 13:45:20 2013 -0700
>
> sched: replace PF_THREAD_BOUND with PF_NO_SETAFFINITY
>
> PF_THREAD_BOUND was originally used to mark kernel threads which were
> bound to a specific CPU using kthread_bind() and a task with the flag
> set allows cpus_allowed modifications only to itself. Workqueue is
> currently abusing it to prevent userland from meddling with
> cpus_allowed of workqueue workers.
>
>
Yes,I had also checked this patch. Actually,the PF_THREAD_BOUND had been replaced with PF_NO_SETAFFINITY.
However, Kernel still disallow attaching kthreadd or threads with flag 0x04000000 to cgroups.
-#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */
+#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index a32f943..3852d92 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
<at> <at> -2224,11 +2224,11 <at> <at> retry_find_task:
tsk = tsk->group_leader;
/*
- * Workqueue threads may acquire PF_THREAD_BOUND and become
+ * Workqueue threads may acquire PF_NO_SETAFFINITY and become
* trapped in a cpuset, or RT worker may be born in a cgroup
* with no rt_runtime allocated. Just say no.
*/
- if (tsk == kthreadd_task || (tsk->flags & PF_THREAD_BOUND)) {
+ if (tsk == kthreadd_task || (tsk->flags & PF_NO_SETAFFINITY)) {
ret = -EINVAL;
rcu_read_unlock();
goto out_unlock_cgroup;
>> + #kernel commit: c4c27fbdda4e8ba87806c415b6d15266b07bce4b
>> + tst_kvercmp 3 4 0
>> + if [ $? -ne 0 ]; then
>
> And where to go if tst_kvercmp failed and return -1?
For kernel <3.4, we just attach all tasks to the cgroup as before.
"do_echo 1 1 "$cur_pid" /dev/cgroup/subgroup_1/tasks"
I had test passed with the v2 patch on kernel 3.10.
cgroup_test_fj 1 TPASS : case98(function 1 1 1 1 1 3 1 1 1) PASS
/tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 31010 Killed $TESTROOT/cgroup_fj_proc
/tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 31012 Killed $TESTROOT/cgroup_fj_proc
cgroup_test_fj 1 TPASS : case99(function 1 1 1 1 1 3 2 1 1) PASS
/tmp/ltp/ltp/testcases/bin/cgroup_fj_function.sh: line 273: 31511 Killed $TESTROOT/cgroup_fj_proc
/tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 31513 Killed $TESTROOT/cgroup_fj_proc
cgroup_test_fj 1 TPASS : case100(function 1 1 1 1 1 3 4 1 1) PASS
/tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 32010 Killed
Regards,
Li Jinyue
>
>> + thread_flag=`cat /proc/$cur_pid/stat | awk '{print $9}'`
>> + if [ $cur_pid -eq 2 -o $((${thread_flag}&0x04000000)) -eq 67108864 ];then
>
> These magic numbers must at least be commented to be understand easily.
>
> Thanks,
> Wanlong Gao
>
>> + continue
>> + fi
>> + fi
>> do_echo 1 1 "$cur_pid" /dev/cgroup/subgroup_1/tasks
>> fi
>> done
>>
>
>
> .
>
------------------------------------------------------------------------------
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^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups on kernel > 3.4.0
2015-01-28 8:49 ` Lijinyue
@ 2015-01-28 9:07 ` Wanlong Gao
2015-01-28 9:28 ` Lijinyue
0 siblings, 1 reply; 7+ messages in thread
From: Wanlong Gao @ 2015-01-28 9:07 UTC (permalink / raw)
To: Lijinyue; +Cc: ltp-list, dingguofu, zhanyongming
On 01/28/2015 04:49 PM, Lijinyue wrote:
> On 2015/1/28 16:23, Wanlong Gao wrote:
>> On 01/19/2015 04:36 PM, Li Jinyue wrote:
>>> For kernel commit c4c27fbdda4e8ba87806c415b6d15266b07bce4b,
>>> disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups.
>>>
>>> So, we kindly avoid to attach these threads in cgroup tests.
>>>
>>> Signed-off-by: Li Jinyue <lijinyue@huawei.com>
>>> ---
>>> testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh | 10 ++++++++++
>>> 1 file changed, 10 insertions(+)
>>>
>>> diff --git a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
>>> index 30476bd..30fffb6 100755
>>> --- a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
>>> +++ b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
>>> @@ -186,6 +186,16 @@ case $attach_operation in
>>> do
>>> cur_pid=`sed -n "$i""p" $TMPFILE`
>>> if [ -e /proc/$cur_pid/ ];then
>>> + #For kernel 3.4.0 and higher,kernel disallow attaching kthreadd or
>>> + #PF_THREAD_BOUND threads to cgroups.
>>
>> I check the current kernel and find that this flag already removed now, please check the following
>> commit:
>>
>> commit 14a40ffccd6163bbcd1d6f32b28a88ffe6149fc6
>> Author: Tejun Heo <tj@kernel.org>
>> Date: Tue Mar 19 13:45:20 2013 -0700
>>
>> sched: replace PF_THREAD_BOUND with PF_NO_SETAFFINITY
>>
>> PF_THREAD_BOUND was originally used to mark kernel threads which were
>> bound to a specific CPU using kthread_bind() and a task with the flag
>> set allows cpus_allowed modifications only to itself. Workqueue is
>> currently abusing it to prevent userland from meddling with
>> cpus_allowed of workqueue workers.
>>
>>
> Yes,I had also checked this patch. Actually,the PF_THREAD_BOUND had been replaced with PF_NO_SETAFFINITY.
> However, Kernel still disallow attaching kthreadd or threads with flag 0x04000000 to cgroups.
I know, I mean you should comment this change at least, because future users may
ask, "what's PF_THREAD_BOUND ? I never see this flag".
And as I said, you should also comment that the 0x04000000 is just PF_THREAD_BOUND or PF_NO_SETAFFINITY,
because you used it in the following code but others don't know where this magic number come from.
Thanks,
Wanlong Gao
> -#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */
> +#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */
>
> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
> index a32f943..3852d92 100644
> --- a/kernel/cgroup.c
> +++ b/kernel/cgroup.c
> <at> <at> -2224,11 +2224,11 <at> <at> retry_find_task:
> tsk = tsk->group_leader;
>
> /*
> - * Workqueue threads may acquire PF_THREAD_BOUND and become
> + * Workqueue threads may acquire PF_NO_SETAFFINITY and become
> * trapped in a cpuset, or RT worker may be born in a cgroup
> * with no rt_runtime allocated. Just say no.
> */
> - if (tsk == kthreadd_task || (tsk->flags & PF_THREAD_BOUND)) {
> + if (tsk == kthreadd_task || (tsk->flags & PF_NO_SETAFFINITY)) {
> ret = -EINVAL;
> rcu_read_unlock();
> goto out_unlock_cgroup;
>>> + #kernel commit: c4c27fbdda4e8ba87806c415b6d15266b07bce4b
>>> + tst_kvercmp 3 4 0
>>> + if [ $? -ne 0 ]; then
>>
>> And where to go if tst_kvercmp failed and return -1?
> For kernel <3.4, we just attach all tasks to the cgroup as before.
> "do_echo 1 1 "$cur_pid" /dev/cgroup/subgroup_1/tasks"
>
> I had test passed with the v2 patch on kernel 3.10.
> cgroup_test_fj 1 TPASS : case98(function 1 1 1 1 1 3 1 1 1) PASS
> /tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 31010 Killed $TESTROOT/cgroup_fj_proc
> /tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 31012 Killed $TESTROOT/cgroup_fj_proc
> cgroup_test_fj 1 TPASS : case99(function 1 1 1 1 1 3 2 1 1) PASS
> /tmp/ltp/ltp/testcases/bin/cgroup_fj_function.sh: line 273: 31511 Killed $TESTROOT/cgroup_fj_proc
> /tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 31513 Killed $TESTROOT/cgroup_fj_proc
> cgroup_test_fj 1 TPASS : case100(function 1 1 1 1 1 3 4 1 1) PASS
> /tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 32010 Killed
>
> Regards,
> Li Jinyue
>>
>>> + thread_flag=`cat /proc/$cur_pid/stat | awk '{print $9}'`
>>> + if [ $cur_pid -eq 2 -o $((${thread_flag}&0x04000000)) -eq 67108864 ];then
>>
>> These magic numbers must at least be commented to be understand easily.
>>
>> Thanks,
>> Wanlong Gao
>>
>>> + continue
>>> + fi
>>> + fi
>>> do_echo 1 1 "$cur_pid" /dev/cgroup/subgroup_1/tasks
>>> fi
>>> done
>>>
>>
>>
>> .
>>
>
>
> .
>
------------------------------------------------------------------------------
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^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups on kernel > 3.4.0
2015-01-28 9:07 ` Wanlong Gao
@ 2015-01-28 9:28 ` Lijinyue
0 siblings, 0 replies; 7+ messages in thread
From: Lijinyue @ 2015-01-28 9:28 UTC (permalink / raw)
To: gaowanlong; +Cc: ltp-list, dingguofu, zhanyongming
On 2015/1/28 17:07, Wanlong Gao wrote:
> On 01/28/2015 04:49 PM, Lijinyue wrote:
>> On 2015/1/28 16:23, Wanlong Gao wrote:
>>> On 01/19/2015 04:36 PM, Li Jinyue wrote:
>>>> For kernel commit c4c27fbdda4e8ba87806c415b6d15266b07bce4b,
>>>> disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups.
>>>>
>>>> So, we kindly avoid to attach these threads in cgroup tests.
>>>>
>>>> Signed-off-by: Li Jinyue <lijinyue@huawei.com>
>>>> ---
>>>> testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh | 10 ++++++++++
>>>> 1 file changed, 10 insertions(+)
>>>>
>>>> diff --git a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
>>>> index 30476bd..30fffb6 100755
>>>> --- a/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
>>>> +++ b/testcases/kernel/controllers/cgroup_fj/cgroup_fj_function.sh
>>>> @@ -186,6 +186,16 @@ case $attach_operation in
>>>> do
>>>> cur_pid=`sed -n "$i""p" $TMPFILE`
>>>> if [ -e /proc/$cur_pid/ ];then
>>>> + #For kernel 3.4.0 and higher,kernel disallow attaching kthreadd or
>>>> + #PF_THREAD_BOUND threads to cgroups.
>>>
>>> I check the current kernel and find that this flag already removed now, please check the following
>>> commit:
>>>
>>> commit 14a40ffccd6163bbcd1d6f32b28a88ffe6149fc6
>>> Author: Tejun Heo <tj@kernel.org>
>>> Date: Tue Mar 19 13:45:20 2013 -0700
>>>
>>> sched: replace PF_THREAD_BOUND with PF_NO_SETAFFINITY
>>>
>>> PF_THREAD_BOUND was originally used to mark kernel threads which were
>>> bound to a specific CPU using kthread_bind() and a task with the flag
>>> set allows cpus_allowed modifications only to itself. Workqueue is
>>> currently abusing it to prevent userland from meddling with
>>> cpus_allowed of workqueue workers.
>>>
>>>
>> Yes,I had also checked this patch. Actually,the PF_THREAD_BOUND had been replaced with PF_NO_SETAFFINITY.
>> However, Kernel still disallow attaching kthreadd or threads with flag 0x04000000 to cgroups.
>
>
> I know, I mean you should comment this change at least, because future users may
> ask, "what's PF_THREAD_BOUND ? I never see this flag".
>
> And as I said, you should also comment that the 0x04000000 is just PF_THREAD_BOUND or PF_NO_SETAFFINITY,
> because you used it in the following code but others don't know where this magic number come from.
>
> Thanks,
> Wanlong Gao
>
>
Yes, I misunderstand it. Thanks for the advice.^V^
I'll comment this in the code.
Thanks,
Li Jinyue
>> -#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */
>> +#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */
>>
>> diff --git a/kernel/cgroup.c b/kernel/cgroup.c
>> index a32f943..3852d92 100644
>> --- a/kernel/cgroup.c
>> +++ b/kernel/cgroup.c
>> <at> <at> -2224,11 +2224,11 <at> <at> retry_find_task:
>> tsk = tsk->group_leader;
>>
>> /*
>> - * Workqueue threads may acquire PF_THREAD_BOUND and become
>> + * Workqueue threads may acquire PF_NO_SETAFFINITY and become
>> * trapped in a cpuset, or RT worker may be born in a cgroup
>> * with no rt_runtime allocated. Just say no.
>> */
>> - if (tsk == kthreadd_task || (tsk->flags & PF_THREAD_BOUND)) {
>> + if (tsk == kthreadd_task || (tsk->flags & PF_NO_SETAFFINITY)) {
>> ret = -EINVAL;
>> rcu_read_unlock();
>> goto out_unlock_cgroup;
>>>> + #kernel commit: c4c27fbdda4e8ba87806c415b6d15266b07bce4b
>>>> + tst_kvercmp 3 4 0
>>>> + if [ $? -ne 0 ]; then
>>>
>>> And where to go if tst_kvercmp failed and return -1?
>> For kernel <3.4, we just attach all tasks to the cgroup as before.
>> "do_echo 1 1 "$cur_pid" /dev/cgroup/subgroup_1/tasks"
>>
>> I had test passed with the v2 patch on kernel 3.10.
>> cgroup_test_fj 1 TPASS : case98(function 1 1 1 1 1 3 1 1 1) PASS
>> /tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 31010 Killed $TESTROOT/cgroup_fj_proc
>> /tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 31012 Killed $TESTROOT/cgroup_fj_proc
>> cgroup_test_fj 1 TPASS : case99(function 1 1 1 1 1 3 2 1 1) PASS
>> /tmp/ltp/ltp/testcases/bin/cgroup_fj_function.sh: line 273: 31511 Killed $TESTROOT/cgroup_fj_proc
>> /tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 31513 Killed $TESTROOT/cgroup_fj_proc
>> cgroup_test_fj 1 TPASS : case100(function 1 1 1 1 1 3 4 1 1) PASS
>> /tmp/ltp/ltp/testcases/bin/cgroup_fj_utility.sh: line 497: 32010 Killed
>>
>> Regards,
>> Li Jinyue
>>>
>>>> + thread_flag=`cat /proc/$cur_pid/stat | awk '{print $9}'`
>>>> + if [ $cur_pid -eq 2 -o $((${thread_flag}&0x04000000)) -eq 67108864 ];then
>>>
>>> These magic numbers must at least be commented to be understand easily.
>>>
>>> Thanks,
>>> Wanlong Gao
>>>
>>>> + continue
>>>> + fi
>>>> + fi
>>>> do_echo 1 1 "$cur_pid" /dev/cgroup/subgroup_1/tasks
>>>> fi
>>>> done
>>>>
>>>
>>>
>>> .
>>>
>>
>>
>> .
>>
>
>
> .
>
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^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [LTP] [PATCH v3] controllers: disallow attaching kthreadd or threads with flag 0x04000000 to cgroups on kernel > 3.4.0
[not found] ` <54C9DCBE.9010609@huawei.com>
@ 2015-01-29 11:35 ` Cyril Hrubis
0 siblings, 0 replies; 7+ messages in thread
From: Cyril Hrubis @ 2015-01-29 11:35 UTC (permalink / raw)
To: Lijinyue; +Cc: ltp-list, dingguofu, zhanyongming
Hi!
Pushed, thanks.
--
Cyril Hrubis
chrubis@suse.cz
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Dive into the World of Parallel Programming. The Go Parallel Website,
sponsored by Intel and developed in partnership with Slashdot Media, is your
hub for all things parallel software development, from weekly thought
leadership blogs to news, videos, case studies, tutorials and more. Take a
look and join the conversation now. http://goparallel.sourceforge.net/
_______________________________________________
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^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2015-01-29 11:35 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2015-01-19 8:36 [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads to cgroups on kernel > 3.4.0 Li Jinyue
2015-01-26 15:22 ` Cyril Hrubis
[not found] ` <54C9DCBE.9010609@huawei.com>
2015-01-29 11:35 ` [LTP] [PATCH v3] controllers: disallow attaching kthreadd or threads with flag 0x04000000 " Cyril Hrubis
2015-01-28 8:23 ` [LTP] [PATCH] controllers: disallow attaching kthreadd or PF_THREAD_BOUND threads " Wanlong Gao
2015-01-28 8:49 ` Lijinyue
2015-01-28 9:07 ` Wanlong Gao
2015-01-28 9:28 ` Lijinyue
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