On 21.08.2014 [16:14:02 +0800], Li Zhong wrote:
> With commit 2fabf084b, during boottime, cpu_numa_callback() is called
> earlier(before their online) for each cpu, and verify_cpu_node_mapping()
> uses cpu_to_node() to check whether siblings are in the same node.
>
> It skips the checking for siblings that are not online yet. So the only
> check done here is for the bootcpu, which is online at that time. But
> the per-cpu numa_node cpu_to_node() uses hasn't been set up yet (which
> will be set up in smp_prepare_cpus()).
>
> So I could see something like following reported:
> [ 0.000000] CPU thread siblings 1/2/3 and 0 don't belong to the same
> node!
You mean you did see this, right? (as opposed to "could" based upon code
inspection or something)
>
> As we don't actually do the checking during this early stage, so maybe
> we could directly call numa_setup_cpu() in do_init_bootmem()?
>
> Signed-off-by: Li Zhong <zh...@linux.vnet.ibm.com>
Acked-by: Nishanth Aravamudan <n...@linux.vnet.ibm.com>
> ---
> arch/powerpc/mm/numa.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
> index d7737a5..9918c02 100644
> --- a/arch/powerpc/mm/numa.c
> +++ b/arch/powerpc/mm/numa.c
> @@ -1128,8 +1128,7 @@ void __init do_init_bootmem(void)
> * early in boot, cf. smp_prepare_cpus().
> */
> for_each_possible_cpu(cpu) {
> - cpu_numa_callback(&ppc64_numa_nb, CPU_UP_PREPARE,
> - (void *)(unsigned long)cpu);
> + numa_setup_cpu((unsigned long)cpu);
This is a good change, thanks for catching it. I must have glossed over
those messages in my testing, my apologies!
-Nish
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
