Re: [PATCH v3 2/6] mm/numa: Skip NUMA_NO_NODE and online nodes in numa_map_to_online_node()

From: Aneesh Kumar K.V
Date: Mon Jan 20 2020 - 20:36:53 EST


Dan Williams <dan.j.williams@xxxxxxxxx> writes:

> Update numa_map_to_online_node() to stop falling back to numa node 0
> when the input is NUMA_NO_NODE. Also, skip the lookup if @node is
> online. This makes the routine compatible with other arch node mapping
> routines.
>
> Reported-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
> Link: https://lore.kernel.org/r/157401275716.43284.13185549705765009174.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> ---
> mm/mempolicy.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> index 4cff069279f6..30d76db718bf 100644
> --- a/mm/mempolicy.c
> +++ b/mm/mempolicy.c
> @@ -137,8 +137,8 @@ int numa_map_to_online_node(int node)
> {
> int min_node;
>
> - if (node == NUMA_NO_NODE)
> - node = 0;
> + if (node == NUMA_NO_NODE || node_online(node))
> + return node;
>
> min_node = node;
> if (!node_online(node)) {


The above if condition will always be true?

-aneesh