Re: About rebuild 2.4.x kernel to support SMP.

[buhr@stat.wisc.edu (Kevin Buhr)]

Yiping Chen <YipingChen@via.com.tw> writes:
> 
> So, I have two question now, 
> 1. how to determine whether your kernel support SMP?

Type "uname -a", as you did before:

>      Linux lab5-1 2.4.2-2 #1 SMP Wed Apr 25 18:56:05 CST 2001 i686 unknown
                               ^^^
SMP appears here if and only if your kernel was compiled as an SMP
kernel (i.e., with CONFIG_SMP set).  Programmatically, you can get
this same information from the "uname" system call.  The "version"
member for the "utsname" structure will be the complete string:

        #1 SMP Wed Apr 25 18:56:05 CST 2001

That is, you should be able to reliably determine whether or not the
kernel is SMP by simply "strstr"ing for " SMP " in the version string.

> 2. I remember in 2.2.x, when I rebuild the kernel which support SMP, the
> compile
>     argument will include -D__SMP__ , but this time, when I rebuild kernel
> 2.4.2-2 , it didn't  appear.
>     Why? 

The "__SMP__" preprocessor define has been replaced by the
"CONFIG_SMP" configuration file variable.

Kevin <buhr@stat.wisc.edu>