Ok everything is clear now thanks for your time, i will search a while and try to code that syscall :)
Thanks again.
On 4 Jun 2015 16:18, "nick" <xerofoify@xxxxxxxxx> wrote:
On 2015-06-04 09:16 AM, Mustafa Hussain wrote:
> I mean how can we use the pid in the scenario of finding the process that
> is not used.
Just check if the process is in the TASK_RUNNING state if it is then
it's in a runnable state, waiting to run on the queue. Otherwise
it's idling waiting for something or has completed its work.
Nick
> On 4 Jun 2015 16:00, "nick" <xerofoify@xxxxxxxxx> wrote:
>
>>
>>
>> On 2015-06-04 08:52 AM, Mustafa Hussain wrote:
>>> Ok, everything is clear except one thing what we will do exactly with
>> (pid)
>>> s?
>>> On 4 Jun 2015 15:40, "nick" <xerofoify@xxxxxxxxx> wrote:
>>>
>> Its used in task struct to create a doubly linked list with init/systemd
>> being the head or first process and the others linked in other of their
>> hierarchy.
>> Nick
>>>>
>>>>
>>>> On 2015-06-04 08:34 AM, Mustafa Hussain wrote:
>>>>> great, How can I check if this running task is used or not.. I mean by
>>>> not
>>>>> used that the task is running but not used by the user
>>>>>
>>>>>
>>>> Here is the issue through in order to find out what tasks the user is
>>>> running we
>>>> need to known the exact pid(s) each time. This is next to impossible to
>> do
>>>> without
>>>> writing a syscall and that’s a little beyond you if your asking about
>> the
>>>> scheduler.
>>>> However, there may be a debugging feature in perf or other tool that
>> does
>>>> this, you
>>>> can google to see if something wrote a tool or kernel module for this.
>>>> Nick
>>>>> On June 4, 2015 8:22:03 AM EDT, Mustafa Hussain <
>>>> mustafa.hussain93@xxxxxxxxx>
>>>>> wrote:
>>>>>> So I was just thinking about if i did this i can close apps that is
>>>>>> running
>>>>>> and user don't use them..
>>>>>> On 4 Jun 2015 14:59, "Nicholas Krause" <xerofoify@xxxxxxxxx> wrote:
>>>>>>
>>>>> That's not a idle task, that's a task in the
>>>>> TASK_INTERRUPTIBLE or TASK_RUNNING phase.
>>>>> Nick
>>>>>>>
>>>>>>>
>>>>>>> On June 4, 2015 7:56:30 AM EDT, Mustafa Hussain <
>>>>>>> mustafa.hussain93@xxxxxxxxx> wrote:
>>>>>>>> All i am trying to do is to detect idle task and remove it from the
>>>>>>>> running
>>>>>>>> queue or deactivate it.
>>>>>>> There is no reason for that. The idle tasks are only ever scheduled
>>>>>> when
>>>>>>> there is no other processes able to
>>>>>>> run. So trying to remove them is a
>>>>>>> bad idea.
>>>>>>> Nick
>>>>>>>> Thank you for your patience :)
>>>>>>>> On 4 Jun 2015 14:51, "Nicholas Krause" <xerofoify@xxxxxxxxx> wrote:
>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On June 4, 2015 3:35:25 AM EDT, Mustafa Hussain <
>>>>>>>>> mustafa.hussain93@xxxxxxxxx> wrote:
>>>>>>>>>> System crashes, system can not start
>>>>>>>>>>
>>>>>>>>> I was not thinking and this schedules the idle thread. What are
>>>>>> you
>>>>>>>> trying
>>>>>>>>> to accomplish through.
>>>>>>>>> Nick
>>>>>>>>>>
>>>>>>>>>> On June 3, 2015 9:41:52 PM EDT, Mustafa Hussain
>>>>>>>>>> <mustafa.hussain93@xxxxxxxxx>
>>>>>>>>>> wrote:
>>>>>>>>>>> i want to dequeue the idle task how can i do this ?
>>>>>>>>>> Why there is no point. Clearly your asking questions in order to
>>>>>>>> learn
>>>>>>>>>> the
>>>>>>>>>> scheduler.
>>>>>>>>>> If your interested in learning it I can help but, you need to
>>>>>>>> think
>>>>>>>>>> about
>>>>>>>>>> what you
>>>>>>>>>> trying to accomplish first.
>>>>>>>>>> Nick
>>>>>>>>>>
>>>>>>>>>>> On Thu, Jun 4, 2015 at 3:40 AM, Mustafa Hussain
>>>>>>>>>>> <mustafa.hussain93@xxxxxxxxx
>>>>>>>>>>>> wrote:
>>>>>>>>>>>
>>>>>>>>>>>> Hi nick,
>>>>>>>>>>>> i applied your suggested edit and i got "bad: scheduling from
>>>>>> the
>>>>>>>>>>> idle
>>>>>>>>>>>> thread!"
>>>>>>>>>>>> how can i solve this ?
>>>>>>>>>>>>
>>>>>>>>>>>> On Wed, Jun 3, 2015 at 12:29 AM, nick <xerofoify@xxxxxxxxx>
>>>>>>>> wrote:
>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>> On 2015-06-02 06:25 PM, Valdis.Kletnieks@xxxxxx wrote:
>>>>>>>>>>>>>> On Tue, 02 Jun 2015 23:38:48 +0200, Mustafa Hussain said:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> /*Check if the pointer pointing to the idle class is
>>>>>> equal
>>>>>>>> to
>>>>>>>>>>> prev's
>>>>>>>>>>>>>>>> sched_class*/
>>>>>>>>>>>>>>>> if(prev->sched_class == idle)
>>>>>>>>>>>>>>>> After this condition you can just:
>>>>>>>>>>>>>>>> printk(KERN_INFO "Prev is equal to idle_sched_class,now
>>>>>>>> running
>>>>>>>>>>> the
>>>>>>>>>>>>> idle
>>>>>>>>>>>>>>>> sched_class\n");
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Hopefully, you didn't take Nick's advice without thinking
>>>>>>>> about
>>>>>>>>>>> it....
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> As I type this, powertop tells me:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Summary: 821.8 wakeups/second, 0.0 GPU ops/seconds, 0.0
>>>>>> VFS
>>>>>>>>>>> ops/sec
>>>>>>>>>>>>> and 18.8% CPU use
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> That printk is going to spam your dmesg pretty hard.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> A better question is:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> If prev is about to go idle, *what do you want to do*?
>>>>>> (Hint:
>>>>>>>>>>> newer
>>>>>>>>>>>>>> kernels already do a bunch of stuff when a cpu/core goes
>>>>>> idle,
>>>>>>>>>> you
>>>>>>>>>>>>>> probably want to make sure you're not working against
>>>>>>>> something
>>>>>>>>>>> here...)
>>>>>>>>>>>>>>
>>>>>>>>>>>>> I didn't account for rate limiting the debug messages, forgot
>>>>>>>> about
>>>>>>>>>>> that
>>>>>>>>>>>>> . :)
>>>>>>>>>>>>> I do agree his question is not the best but he wanted a
>>>>>> answer
>>>>>>>> so I
>>>>>>>>>>>>> decided
>>>>>>>>>>>>> to just give him a answer that works for his learning.
>>>>>>>>>>>>> Nick
>>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> --
>>>>>>>>>> Sent from my Android device with K-9 Mail. Please excuse my
>>>>>> brevity.
>>>>>>>>>
>>>>>>>>> --
>>>>>>>>> Sent from my Android device with K-9 Mail. Please excuse my
>>>>>> brevity.
>>>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> Sent from my Android device with K-9 Mail. Please excuse my brevity.
>>>>>>>
>>>>>
>>>>> --
>>>>> Sent from my Android device with K-9 Mail. Please excuse my brevity.
>>>>>
>>>>
>>>
>>
>
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