* Global variables
@ 2015-06-14 11:28 roni
2015-06-14 11:32 ` Ruben Safir
0 siblings, 1 reply; 4+ messages in thread
From: roni @ 2015-06-14 11:28 UTC (permalink / raw)
To: kernelnewbies
I know i should avoid using global variables in kernel programming.
What problem it create if i use more global variables?
^ permalink raw reply [flat|nested] 4+ messages in thread
* Global variables
2015-06-14 11:28 Global variables roni
@ 2015-06-14 11:32 ` Ruben Safir
2015-06-14 11:58 ` AYAN KUMAR HALDER
0 siblings, 1 reply; 4+ messages in thread
From: Ruben Safir @ 2015-06-14 11:32 UTC (permalink / raw)
To: kernelnewbies
On 06/14/2015 07:28 AM, roni wrote:
> I know i should avoid using global variables in kernel programming.
>
> What problem it create if i use more global variables?
>
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>
>
you step on everyone else's names space. Do you know how many other
people are collaborating with the kernel. Stick to your own back yard.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Global variables
2015-06-14 11:32 ` Ruben Safir
@ 2015-06-14 11:58 ` AYAN KUMAR HALDER
2015-06-14 12:53 ` Ruben Safir
0 siblings, 1 reply; 4+ messages in thread
From: AYAN KUMAR HALDER @ 2015-06-14 11:58 UTC (permalink / raw)
To: kernelnewbies
On Sun, Jun 14, 2015 at 5:02 PM, Ruben Safir <ruben@mrbrklyn.com> wrote:
> On 06/14/2015 07:28 AM, roni wrote:
>> I know i should avoid using global variables in kernel programming.
>>
>> What problem it create if i use more global variables?
>>
>>
>> _______________________________________________
>> Kernelnewbies mailing list
>> Kernelnewbies at kernelnewbies.org
>> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>>
>>
>
>
> you step on everyone else's names space. Do you know how many other
> people are collaborating with the kernel. Stick to your own back yard.
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
Besides, it hampers reentrancy, unless you use locks(mutex) with each
global variable.
Kernel functions can be called by different processes in parallel and
they might also be
called/scheduled from interrupt context.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Global variables
2015-06-14 11:58 ` AYAN KUMAR HALDER
@ 2015-06-14 12:53 ` Ruben Safir
0 siblings, 0 replies; 4+ messages in thread
From: Ruben Safir @ 2015-06-14 12:53 UTC (permalink / raw)
To: kernelnewbies
On 06/14/2015 07:58 AM, AYAN KUMAR HALDER wrote:
> Besides, it hampers reentrancy, unless you use locks(mutex) with each
> global variable.
This is not necessary a function of globalization of variables, although
it damn sure can be, but... honestly, if he is asking this question, it
is not likely that he yet understands race conditions and critical areas.
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2015-06-14 12:53 UTC | newest]
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2015-06-14 11:28 Global variables roni
2015-06-14 11:32 ` Ruben Safir
2015-06-14 11:58 ` AYAN KUMAR HALDER
2015-06-14 12:53 ` Ruben Safir
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