Re: [PATCH v2] x86: Move per cpu cpu_llc_shared_map to a field instruct cpuinfo_x86

[Ingo Molnar]

* Kevin Winchester <kjwinchester@xxxxxxxxx> wrote:

> Commit 141168c36cde ("x86: Simplify code by removing a !SMP #ifdefs from
> 'struct cpuinfo_x86'") caused the compilation error:
> 
> mce_amd.c:(.cpuinit.text+0x4723): undefined reference to 'cpu_llc_shared_map'
> 
> by removing an #ifdef CONFIG_SMP around a block containing a reference
> to cpu_llc_shared_map.  Rather than replace the #ifdef, move
> cpu_llc_shared_map to be a new cpumask_t field llc_shared_map in
> struct cpuinfo_x86 and adjust all references to cpu_llc_shared_map.
> 
> The size effects on various kernels are as follows:
> 
>    text	   data	    bss	    dec	    hex	filename
> 5281572	 513296	1044480	6839348	 685c34	vmlinux.up
> 5281572	 513296	1044480	6839348	 685c34	vmlinux.up.patched
> 5548860	 516792	1110016	7175668	 6d7df4	vmlinux.smp.2
> 5548837	 516792	1110016	7175645	 6d7ddd	vmlinux.smp.2.patched
> 5595965	 706840	1310720	7613525	 742c55	vmlinux.smp.max
> 5595876	 707880	1310720	7614476	 74300c	vmlinux.smp.max.patched
> 
> It can be seen that this change has no effect on UP, a minor effect for
> SMP with Max 2 CPUs, and a more substantial but still not overly large
> effect for MAXSMP.
> 
> Signed-off-by: Kevin Winchester <kjwinchester@xxxxxxxxx>
> ---
> 
> I'm still wondering if I should I give the same treatment to:
> 
> cpu_sibling_map
> cpu_core_map
> cpu_llc_id
> cpu_number
> 
> or is that going too far?
> 
>  arch/x86/include/asm/processor.h      |    1 +
>  arch/x86/include/asm/smp.h            |    6 ------
>  arch/x86/kernel/cpu/intel_cacheinfo.c |    4 ++--
>  arch/x86/kernel/cpu/mcheck/mce_amd.c  |    7 ++++---
>  arch/x86/kernel/smpboot.c             |   15 ++++++---------
>  arch/x86/xen/smp.c                    |    1 -
>  6 files changed, 13 insertions(+), 21 deletions(-)

Yeah, I'd definitely give them the same treatment.

Would you like to update your series? I'd suggest you keep patch 
#1 in place, as it's already probably reasonably well tested.

Thanks,

	Ingo
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