Module vs Kernel main performacne

Peter Senna Tschudin peter.senna at
Thu Jun 7 09:11:42 EDT 2012

Hello Abu,

I had to include <linux/module.h> or an error was issued about "THIS_MODULE".

What Kernel version are you using? I'm trying to compile it and I'm
getting the error:

[peter at ace m]$ make
make -C /lib/modules/3.3.7-1.fc17.x86_64/build SUBDIRS=`pwd` modules
make[1]: Entering directory `/usr/src/kernels/3.3.7-1.fc17.x86_64'
  CC [M]  /tmp/m/m.o
/tmp/m/m.c:36:2: error: unknown field ‘ioctl’ specified in initializer
/tmp/m/m.c:36:2: warning: initialization from incompatible pointer
type [enabled by default]
/tmp/m/m.c:36:2: warning: (near initialization for ‘m_fops.llseek’)
[enabled by default]
make[2]: *** [/tmp/m/m.o] Error 1
make[1]: *** [_module_/tmp/m] Error 2
make[1]: Leaving directory `/usr/src/kernels/3.3.7-1.fc17.x86_64'
make: *** [module] Error 2

According to:

There is no .ioctl at struct file_operations...

Can you share how you've used perf/oprofile on your module/Kernel code?



On Fri, Jun 1, 2012 at 3:52 PM, Abu Rasheda <rcpilot2010 at> wrote:
>> If the buffer at user side is more then a page, then it may be that
>> complete user space buffer is not available in memory and kernel spend time
>> in processing page fault
> I have attached code for module and user program. If anyone is bored over
> the weekend they are welcome to try and explain the behavior.
> Abu Rasheda
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at

Peter Senna Tschudin
peter.senna at
gpg id: 48274C36

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