Re: ip_contrack module refuses to load...

[david mosberger <dmosberger@gmail.com>]

The module-loader does it's own UP special-casing.  For example,
percpu_modcopy() is a dummy routine in the UP case, apparently because
there is not supposed to be any per-CPU module data for the UP case.

  --david

On 8/30/05, Luck, Tony <tony.luck@intel.com> wrote:
> 
> >> so all the
> >> space allocation, mapping, and relocation code should be the same
> >> for UP and SMP ... shouldn't they?
> >
> >No, in the UP case, we can simply map the per-CPU section in the
> >kernel image whereas in the SMP case, each CPU needs its own copy of
> >the per-CPU section.  To see this, look for per_cpu_init(): in the SMP
> >case, it copies the section, in the UP-case, it simply returns
> >__phys_per_cpu_start (a pointer into the per-CPU section).
> 
> You are (as usual) correct.
> 
> But this shouldn't make any difference for the module loading
> case ... whether the memory backing the per-cpu area is physically
> within a special section in the kernel data, or allocated from
> __alloc_bootmem() in a big array for all cpus (mm/contig.c case),
> or done in scattered allocations across nodes (mm/discontig.c case).
> So, if the module loader has special UP code, then it shouldn't.
> 
> -Tony
> 


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