From mboxrd@z Thu Jan  1 00:00:00 1970
From: ramya.desai@gmail.com (Ramya Desai)
Date: Wed, 27 Apr 2011 14:16:08 +0530
Subject: What is the adventage of macros against function
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To: kernelnewbies@lists.kernelnewbies.org
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2011/4/27 ?smail Baydan <ibaydan@gmail.com>:
> Currently I am trying to learn linux kernel while looking around I saw that
> a lot of function likes macros are defined.What is the adventage of macros
> over functions.
If the size of the function is very small, then the macro is better
when compared to function. The macros are replaced at the time of
preprocessing. However, if there is a function, then there may be
overhead in calling the function. When there is a call, the return
address needs to be stored on the stack. This makes some overhead. So,
if the size of a fucction is big, then define it as function otherwise
make it as a macro.

I guess, this helps you a bit.

Regards,
Ramya.

> Thanks
>
> --
> ?smail Baydan
>
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