Re: [PATCH v7 12/14] arm64/numa: remove the limitation that cpu0 must bind to node0

Will Deacon
2016-08-26T16:00:57Z

On Wed, Aug 24, 2016 at 03:44:51PM +0800, Zhen Lei wrote:
> 1. Currently only cpu0 set on cpu_possible_mask and percpu areas have not
> been initialized.
> 2. No reason to limit cpu0 must belongs to node0.

Whilst I suspect you're using enumerated lists in order to try to make
things clearer, I'm having a really hard time understanding the commit
messages you have in this series. It's actually much better if you
structure them as concise paragraphs explaining:

- What is the problem that you're fixing?

- How does that problem manifest?

- How does the patch fix it?

As far as I can see, this patch just removes a bunch of code with no
explanation as to why it's not required or any problems caused by
keeping it around.

Will

> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
> ---
> arch/arm64/mm/numa.c | 12 ++----------
> 1 file changed, 2 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
> index 114180f..07a1978 100644
> --- a/arch/arm64/mm/numa.c
> +++ b/arch/arm64/mm/numa.c
> @@ -94,7 +94,6 @@ void numa_clear_node(unsigned int cpu)
> */
> static void __init setup_node_to_cpumask_map(void)
> {
> - unsigned int cpu;
> int node;
>
> /* setup nr_node_ids if not done yet */
> @@ -107,9 +106,6 @@ static void __init setup_node_to_cpumask_map(void)
> cpumask_clear(node_to_cpumask_map[node]);
> }
>
> - for_each_possible_cpu(cpu)
> - set_cpu_numa_node(cpu, NUMA_NO_NODE);
> -
> /* cpumask_of_node() will now work */
> pr_debug("Node to cpumask map for %d nodes\n", nr_node_ids);
> }
> @@ -119,13 +115,13 @@ static void __init setup_node_to_cpumask_map(void)
> */
> void numa_store_cpu_info(unsigned int cpu)
> {
> - map_cpu_to_node(cpu, numa_off ? 0 : cpu_to_node_map[cpu]);
> + map_cpu_to_node(cpu, cpu_to_node_map[cpu]);
> }
>
> void __init early_map_cpu_to_node(unsigned int cpu, int nid)
> {
> /* fallback to node 0 */
> - if (nid < 0 || nid >= MAX_NUMNODES)
> + if (nid < 0 || nid >= MAX_NUMNODES || numa_off)
> nid = 0;
>
> cpu_to_node_map[cpu] = nid;
> @@ -375,10 +371,6 @@ static int __init numa_init(int (*init_func)(void))
>
> setup_node_to_cpumask_map();
>
> - /* init boot processor */
> - cpu_to_node_map[0] = 0;
> - map_cpu_to_node(0, 0);
> -
> return 0;
> }
>
> --
> 2.5.0
>
>