On Wed, Apr 13, 2022 at 2:22 AM Jagdish Gediya <jvgediya@xxxxxxxxxxxxx> wrote:
>
> Current implementation to find the demotion targets works
> based on node state N_MEMORY, however some systems may have
> dram only memory numa node which are N_MEMORY but not the
> right choices as demotion targets.
>
> Add new state N_DEMOTION_TARGETS, node_states[N_DEMOTION_TARGETS]
> then can be used to hold the list of nodes which can be used
> as demotion targets.
>
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
> Signed-off-by: Jagdish Gediya <jvgediya@xxxxxxxxxxxxx>
> ---
> drivers/base/node.c | 4 ++++
> include/linux/nodemask.h | 1 +
> 2 files changed, 5 insertions(+)
>
> diff --git a/drivers/base/node.c b/drivers/base/node.c
> index ec8bb24a5a22..cd79815b0f7a 100644
> --- a/drivers/base/node.c
> +++ b/drivers/base/node.c
> @@ -1038,6 +1038,9 @@ static struct node_attr node_state_attr[] = {
> [N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
> [N_GENERIC_INITIATOR] = _NODE_ATTR(has_generic_initiator,
> N_GENERIC_INITIATOR),
> + [N_DEMOTION_TARGETS] = _NODE_ATTR(has_demotion_targets,
> + N_DEMOTION_TARGETS),
These nodes are demotion targets themselves. It is not the case that
they have demotion targets. Let's rename "has_demotion_targets" to
"demotion_targets"?
> +
> };
>
> static struct attribute *node_state_attrs[] = {
> @@ -1050,6 +1053,7 @@ static struct attribute *node_state_attrs[] = {
> &node_state_attr[N_MEMORY].attr.attr,
> &node_state_attr[N_CPU].attr.attr,
> &node_state_attr[N_GENERIC_INITIATOR].attr.attr,
> + &node_state_attr[N_DEMOTION_TARGETS].attr.attr,
> NULL
> };
>
> diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
> index 567c3ddba2c4..17844300fd57 100644
> --- a/include/linux/nodemask.h
> +++ b/include/linux/nodemask.h
> @@ -400,6 +400,7 @@ enum node_states {
> N_MEMORY, /* The node has memory(regular, high, movable) */
> N_CPU, /* The node has one or more cpus */
> N_GENERIC_INITIATOR, /* The node has one or more Generic Initiators */
> + N_DEMOTION_TARGETS, /* Nodes that should be considered as demotion targets */
> NR_NODE_STATES
> };
>
> --
> 2.35.1
>
>
