Re: [PATCH] mm/alloc: fallback to first node if the wanted node offline

From: Pingfan Liu
Date: Thu Dec 06 2018 - 05:04:10 EST


[...]
> THanks for pointing this out. It made my life easier. So It think the
> bug is that we call init_memory_less_node from this path. I suspect
> numa_register_memblks is the right place to do this. So I admit I
> am not 100% sure but could you give this a try please?
>
Sure.

> diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
> index 1308f5408bf7..4575ae4d5449 100644
> --- a/arch/x86/mm/numa.c
> +++ b/arch/x86/mm/numa.c
> @@ -527,6 +527,19 @@ static void __init numa_clear_kernel_node_hotplug(void)
> }
> }
>
> +static void __init init_memory_less_node(int nid)
> +{
> + unsigned long zones_size[MAX_NR_ZONES] = {0};
> + unsigned long zholes_size[MAX_NR_ZONES] = {0};
> +
> + free_area_init_node(nid, zones_size, 0, zholes_size);
> +
> + /*
> + * All zonelists will be built later in start_kernel() after per cpu
> + * areas are initialized.
> + */
> +}
> +
> static int __init numa_register_memblks(struct numa_meminfo *mi)
> {
> unsigned long uninitialized_var(pfn_align);
> @@ -592,6 +605,8 @@ static int __init numa_register_memblks(struct numa_meminfo *mi)
> continue;
>
> alloc_node_data(nid);
> + if (!end)
> + init_memory_less_node(nid);
> }
>
> /* Dump memblock with node info and return. */
> @@ -721,21 +736,6 @@ void __init x86_numa_init(void)
> numa_init(dummy_numa_init);
> }
>
> -static void __init init_memory_less_node(int nid)
> -{
> - unsigned long zones_size[MAX_NR_ZONES] = {0};
> - unsigned long zholes_size[MAX_NR_ZONES] = {0};
> -
> - /* Allocate and initialize node data. Memory-less node is now online.*/
> - alloc_node_data(nid);
> - free_area_init_node(nid, zones_size, 0, zholes_size);
> -
> - /*
> - * All zonelists will be built later in start_kernel() after per cpu
> - * areas are initialized.
> - */
> -}
> -
> /*
> * Setup early cpu_to_node.
> *
> @@ -763,9 +763,6 @@ void __init init_cpu_to_node(void)
> if (node == NUMA_NO_NODE)
> continue;
>
> - if (!node_online(node))
> - init_memory_less_node(node);
> -
> numa_set_node(cpu, node);
> }
> }
> --
Which commit is this patch applied on? I can not apply it on latest linux tree.

Thanks,
Pingfan