Re: [PATCH] x86/numa: move setting parse numa node to num_add_memblk

From: Michal Hocko
Date: Wed Nov 29 2017 - 07:03:35 EST


On Wed 29-11-17 17:13:27, zhong jiang wrote:
> Currently, Arm64 and x86 use the common code wehn parsing numa node
> in a acpi way. The arm64 will set the parsed node in numa_add_memblk,
> but the x86 is not set in that , then it will result in the repeatly
> setting. And the parsed node maybe is unreasonable to the system.
>
> we would better not set it although it also still works. because the
> parsed node is unresonable. so we should skip related operate in this
> node. This patch just set node in various architecture individually.
> it is no functional change.

I really have hard time to understand what you try to say above. Could
you start by the problem description and then how you are addressing it?

> Signed-off-by: zhong jiang <zhongjiang@xxxxxxxxxx>
> ---
> arch/x86/mm/amdtopology.c | 1 -
> arch/x86/mm/numa.c | 3 ++-
> drivers/acpi/numa.c | 5 ++++-
> 3 files changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/mm/amdtopology.c b/arch/x86/mm/amdtopology.c
> index 91f501b..7657042 100644
> --- a/arch/x86/mm/amdtopology.c
> +++ b/arch/x86/mm/amdtopology.c
> @@ -151,7 +151,6 @@ int __init amd_numa_init(void)
>
> prevbase = base;
> numa_add_memblk(nodeid, base, limit);
> - node_set(nodeid, numa_nodes_parsed);
> }
>
> if (!nodes_weight(numa_nodes_parsed))
> diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
> index 25504d5..8f87f26 100644
> --- a/arch/x86/mm/numa.c
> +++ b/arch/x86/mm/numa.c
> @@ -150,6 +150,8 @@ static int __init numa_add_memblk_to(int nid, u64 start, u64 end,
> mi->blk[mi->nr_blks].end = end;
> mi->blk[mi->nr_blks].nid = nid;
> mi->nr_blks++;
> +
> + node_set(nid, numa_nodes_parsed);
> return 0;
> }
>
> @@ -693,7 +695,6 @@ static int __init dummy_numa_init(void)
> printk(KERN_INFO "Faking a node at [mem %#018Lx-%#018Lx]\n",
> 0LLU, PFN_PHYS(max_pfn) - 1);
>
> - node_set(0, numa_nodes_parsed);
> numa_add_memblk(0, 0, PFN_PHYS(max_pfn));
>
> return 0;
> diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c
> index 917f1cc..f2e33cb 100644
> --- a/drivers/acpi/numa.c
> +++ b/drivers/acpi/numa.c
> @@ -294,7 +294,9 @@ void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
> goto out_err_bad_srat;
> }
>
> - node_set(node, numa_nodes_parsed);
> + /* some architecture is likely to ignore a unreasonable node */
> + if (!node_isset(node, numa_nodes_parsed))
> + goto out;
>
> pr_info("SRAT: Node %u PXM %u [mem %#010Lx-%#010Lx]%s%s\n",
> node, pxm,
> @@ -309,6 +311,7 @@ void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
>
> max_possible_pfn = max(max_possible_pfn, PFN_UP(end - 1));
>
> +out:
> return 0;
> out_err_bad_srat:
> bad_srat();
> --
> 1.8.3.1

--
Michal Hocko
SUSE Labs