lkml.org 
[lkml]   [2014]   [Jul]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC Patch V1 29/30] mm, x86: Enable memoryless node support to better support CPU/memory hotplug
On 11.07.2014 [15:37:46 +0800], Jiang Liu wrote:
> With current implementation, all CPUs within a NUMA node will be
> assocaited with another NUMA node if the node has no memory installed.

<snip>

> ---
> arch/x86/Kconfig | 3 +++
> arch/x86/kernel/acpi/boot.c | 5 ++++-
> arch/x86/kernel/smpboot.c | 2 ++
> arch/x86/mm/numa.c | 42 +++++++++++++++++++++++++++++++++++-------
> 4 files changed, 44 insertions(+), 8 deletions(-)
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index a8f749ef0fdc..f35b25b88625 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -1887,6 +1887,9 @@ config USE_PERCPU_NUMA_NODE_ID
> def_bool y
> depends on NUMA
>
> +config HAVE_MEMORYLESS_NODES
> + def_bool NUMA
> +
> config ARCH_ENABLE_SPLIT_PMD_PTLOCK
> def_bool y
> depends on X86_64 || X86_PAE
> diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
> index 86281ffb96d6..3b5641703a49 100644
> --- a/arch/x86/kernel/acpi/boot.c
> +++ b/arch/x86/kernel/acpi/boot.c
> @@ -612,6 +612,8 @@ static void acpi_map_cpu2node(acpi_handle handle, int cpu, int physid)
> if (nid != -1) {
> set_apicid_to_node(physid, nid);
> numa_set_node(cpu, nid);
> + if (node_online(nid))
> + set_cpu_numa_mem(cpu, local_memory_node(nid));

How common is it for this method to be called for a CPU on an offline
node? Aren't you fixing this in the next patch (so maybe the order
should be changed?)?

> }
> #endif
> }
> @@ -644,9 +646,10 @@ int acpi_unmap_lsapic(int cpu)
> {
> #ifdef CONFIG_ACPI_NUMA
> set_apicid_to_node(per_cpu(x86_cpu_to_apicid, cpu), NUMA_NO_NODE);
> + set_cpu_numa_mem(cpu, NUMA_NO_NODE);
> #endif
>
> - per_cpu(x86_cpu_to_apicid, cpu) = -1;
> + per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID;

I think this is an unrelated change?

> set_cpu_present(cpu, false);
> num_processors--;
>
> diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
> index 5492798930ef..4a5437989ffe 100644
> --- a/arch/x86/kernel/smpboot.c
> +++ b/arch/x86/kernel/smpboot.c
> @@ -162,6 +162,8 @@ static void smp_callin(void)
> __func__, cpuid);
> }
>
> + set_numa_mem(local_memory_node(cpu_to_node(cpuid)));
> +

Note that you might hit the same issue I reported on powerpc, if
smp_callin() is part of smp_init(). The waitqueue initialization code
depends on cpu_to_node() [and eventually cpu_to_mem()] to be initialized
quite early.

Thanks,
Nish



\
 
 \ /
  Last update: 2014-07-25 02:01    [W:0.326 / U:2.092 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site