[v2,14/18] acpi/numa: Up-level "map to online node" functionality
diff mbox series

Message ID 157401275104.43284.15865121806241743141.stgit@dwillia2-desk3.amr.corp.intel.com
State New
Headers show
Series
  • Memory Hierarchy: Enable target node lookups for reserved memory
Related show

Commit Message

Dan Williams Nov. 17, 2019, 5:45 p.m. UTC
The acpi_map_pxm_to_online_node() helper is used to find the closest
online node to a given proximity domain. This is used to map devices in
a proximity domain with no online memory or cpus to the closest online
node and populate a device's 'numa_node' property. The numa_node
property allows applications to be migrated "close" to a resource.

In preparation for providing a generic facility to optionally map an
address range to its closest online node, or the node the range would
represent were it to be onlined (target_node), up-level the core of
acpi_map_pxm_to_online_node() to a generic mm/numa helper.

Cc: Michal Hocko <mhocko@suse.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/acpi/numa.c  |   41 -----------------------------------------
 include/linux/acpi.h |   23 ++++++++++++++++++++++-
 include/linux/numa.h |    9 +++++++++
 mm/mempolicy.c       |   30 ++++++++++++++++++++++++++++++
 4 files changed, 61 insertions(+), 42 deletions(-)

Comments

Rafael J. Wysocki Nov. 29, 2019, 11:56 a.m. UTC | #1
On Sunday, November 17, 2019 6:45:51 PM CET Dan Williams wrote:
> The acpi_map_pxm_to_online_node() helper is used to find the closest
> online node to a given proximity domain. This is used to map devices in
> a proximity domain with no online memory or cpus to the closest online
> node and populate a device's 'numa_node' property. The numa_node
> property allows applications to be migrated "close" to a resource.
> 
> In preparation for providing a generic facility to optionally map an
> address range to its closest online node, or the node the range would
> represent were it to be onlined (target_node), up-level the core of
> acpi_map_pxm_to_online_node() to a generic mm/numa helper.
> 
> Cc: Michal Hocko <mhocko@suse.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

It looks like this is the only patch in the series needing my attention and
it is fine by me, so

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  drivers/acpi/numa.c  |   41 -----------------------------------------
>  include/linux/acpi.h |   23 ++++++++++++++++++++++-
>  include/linux/numa.h |    9 +++++++++
>  mm/mempolicy.c       |   30 ++++++++++++++++++++++++++++++
>  4 files changed, 61 insertions(+), 42 deletions(-)
> 
> diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c
> index eadbf90e65d1..47b4969d9b93 100644
> --- a/drivers/acpi/numa.c
> +++ b/drivers/acpi/numa.c
> @@ -72,47 +72,6 @@ int acpi_map_pxm_to_node(int pxm)
>  }
>  EXPORT_SYMBOL(acpi_map_pxm_to_node);
>  
> -/**
> - * acpi_map_pxm_to_online_node - Map proximity ID to online node
> - * @pxm: ACPI proximity ID
> - *
> - * This is similar to acpi_map_pxm_to_node(), but always returns an online
> - * node.  When the mapped node from a given proximity ID is offline, it
> - * looks up the node distance table and returns the nearest online node.
> - *
> - * ACPI device drivers, which are called after the NUMA initialization has
> - * completed in the kernel, can call this interface to obtain their device
> - * NUMA topology from ACPI tables.  Such drivers do not have to deal with
> - * offline nodes.  A node may be offline when a device proximity ID is
> - * unique, SRAT memory entry does not exist, or NUMA is disabled, ex.
> - * "numa=off" on x86.
> - */
> -int acpi_map_pxm_to_online_node(int pxm)
> -{
> -	int node, min_node;
> -
> -	node = acpi_map_pxm_to_node(pxm);
> -
> -	if (node == NUMA_NO_NODE)
> -		node = 0;
> -
> -	min_node = node;
> -	if (!node_online(node)) {
> -		int min_dist = INT_MAX, dist, n;
> -
> -		for_each_online_node(n) {
> -			dist = node_distance(node, n);
> -			if (dist < min_dist) {
> -				min_dist = dist;
> -				min_node = n;
> -			}
> -		}
> -	}
> -
> -	return min_node;
> -}
> -EXPORT_SYMBOL(acpi_map_pxm_to_online_node);
> -
>  static void __init
>  acpi_table_print_srat_entry(struct acpi_subtable_header *header)
>  {
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index 8b4e516bac00..aeedd09f2f71 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -401,9 +401,30 @@ extern void acpi_osi_setup(char *str);
>  extern bool acpi_osi_is_win8(void);
>  
>  #ifdef CONFIG_ACPI_NUMA
> -int acpi_map_pxm_to_online_node(int pxm);
>  int acpi_map_pxm_to_node(int pxm);
>  int acpi_get_node(acpi_handle handle);
> +
> +/**
> + * acpi_map_pxm_to_online_node - Map proximity ID to online node
> + * @pxm: ACPI proximity ID
> + *
> + * This is similar to acpi_map_pxm_to_node(), but always returns an online
> + * node.  When the mapped node from a given proximity ID is offline, it
> + * looks up the node distance table and returns the nearest online node.
> + *
> + * ACPI device drivers, which are called after the NUMA initialization has
> + * completed in the kernel, can call this interface to obtain their device
> + * NUMA topology from ACPI tables.  Such drivers do not have to deal with
> + * offline nodes.  A node may be offline when a device proximity ID is
> + * unique, SRAT memory entry does not exist, or NUMA is disabled, ex.
> + * "numa=off" on x86.
> + */
> +static inline int acpi_map_pxm_to_online_node(int pxm)
> +{
> +	int node = acpi_map_pxm_to_node(pxm);
> +
> +	return numa_map_to_online_node(node);
> +}
>  #else
>  static inline int acpi_map_pxm_to_online_node(int pxm)
>  {
> diff --git a/include/linux/numa.h b/include/linux/numa.h
> index 110b0e5d0fb0..20f4e44b186c 100644
> --- a/include/linux/numa.h
> +++ b/include/linux/numa.h
> @@ -13,4 +13,13 @@
>  
>  #define	NUMA_NO_NODE	(-1)
>  
> +#ifdef CONFIG_NUMA
> +int numa_map_to_online_node(int node);
> +#else
> +static inline int numa_map_to_online_node(int node)
> +{
> +	return NUMA_NO_NODE;
> +}
> +#endif
> +
>  #endif /* _LINUX_NUMA_H */
> diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> index 4ae967bcf954..e2d8dd21ce9d 100644
> --- a/mm/mempolicy.c
> +++ b/mm/mempolicy.c
> @@ -127,6 +127,36 @@ static struct mempolicy default_policy = {
>  
>  static struct mempolicy preferred_node_policy[MAX_NUMNODES];
>  
> +/**
> + * numa_map_to_online_node - Find closest online node
> + * @nid: Node id to start the search
> + *
> + * Lookup the next closest node by distance if @nid is not online.
> + */
> +int numa_map_to_online_node(int node)
> +{
> +	int min_node;
> +
> +	if (node == NUMA_NO_NODE)
> +		node = 0;
> +
> +	min_node = node;
> +	if (!node_online(node)) {
> +		int min_dist = INT_MAX, dist, n;
> +
> +		for_each_online_node(n) {
> +			dist = node_distance(node, n);
> +			if (dist < min_dist) {
> +				min_dist = dist;
> +				min_node = n;
> +			}
> +		}
> +	}
> +
> +	return min_node;
> +}
> +EXPORT_SYMBOL_GPL(numa_map_to_online_node);
> +
>  struct mempolicy *get_task_policy(struct task_struct *p)
>  {
>  	struct mempolicy *pol = p->mempolicy;
>

Patch
diff mbox series

diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c
index eadbf90e65d1..47b4969d9b93 100644
--- a/drivers/acpi/numa.c
+++ b/drivers/acpi/numa.c
@@ -72,47 +72,6 @@  int acpi_map_pxm_to_node(int pxm)
 }
 EXPORT_SYMBOL(acpi_map_pxm_to_node);
 
-/**
- * acpi_map_pxm_to_online_node - Map proximity ID to online node
- * @pxm: ACPI proximity ID
- *
- * This is similar to acpi_map_pxm_to_node(), but always returns an online
- * node.  When the mapped node from a given proximity ID is offline, it
- * looks up the node distance table and returns the nearest online node.
- *
- * ACPI device drivers, which are called after the NUMA initialization has
- * completed in the kernel, can call this interface to obtain their device
- * NUMA topology from ACPI tables.  Such drivers do not have to deal with
- * offline nodes.  A node may be offline when a device proximity ID is
- * unique, SRAT memory entry does not exist, or NUMA is disabled, ex.
- * "numa=off" on x86.
- */
-int acpi_map_pxm_to_online_node(int pxm)
-{
-	int node, min_node;
-
-	node = acpi_map_pxm_to_node(pxm);
-
-	if (node == NUMA_NO_NODE)
-		node = 0;
-
-	min_node = node;
-	if (!node_online(node)) {
-		int min_dist = INT_MAX, dist, n;
-
-		for_each_online_node(n) {
-			dist = node_distance(node, n);
-			if (dist < min_dist) {
-				min_dist = dist;
-				min_node = n;
-			}
-		}
-	}
-
-	return min_node;
-}
-EXPORT_SYMBOL(acpi_map_pxm_to_online_node);
-
 static void __init
 acpi_table_print_srat_entry(struct acpi_subtable_header *header)
 {
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 8b4e516bac00..aeedd09f2f71 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -401,9 +401,30 @@  extern void acpi_osi_setup(char *str);
 extern bool acpi_osi_is_win8(void);
 
 #ifdef CONFIG_ACPI_NUMA
-int acpi_map_pxm_to_online_node(int pxm);
 int acpi_map_pxm_to_node(int pxm);
 int acpi_get_node(acpi_handle handle);
+
+/**
+ * acpi_map_pxm_to_online_node - Map proximity ID to online node
+ * @pxm: ACPI proximity ID
+ *
+ * This is similar to acpi_map_pxm_to_node(), but always returns an online
+ * node.  When the mapped node from a given proximity ID is offline, it
+ * looks up the node distance table and returns the nearest online node.
+ *
+ * ACPI device drivers, which are called after the NUMA initialization has
+ * completed in the kernel, can call this interface to obtain their device
+ * NUMA topology from ACPI tables.  Such drivers do not have to deal with
+ * offline nodes.  A node may be offline when a device proximity ID is
+ * unique, SRAT memory entry does not exist, or NUMA is disabled, ex.
+ * "numa=off" on x86.
+ */
+static inline int acpi_map_pxm_to_online_node(int pxm)
+{
+	int node = acpi_map_pxm_to_node(pxm);
+
+	return numa_map_to_online_node(node);
+}
 #else
 static inline int acpi_map_pxm_to_online_node(int pxm)
 {
diff --git a/include/linux/numa.h b/include/linux/numa.h
index 110b0e5d0fb0..20f4e44b186c 100644
--- a/include/linux/numa.h
+++ b/include/linux/numa.h
@@ -13,4 +13,13 @@ 
 
 #define	NUMA_NO_NODE	(-1)
 
+#ifdef CONFIG_NUMA
+int numa_map_to_online_node(int node);
+#else
+static inline int numa_map_to_online_node(int node)
+{
+	return NUMA_NO_NODE;
+}
+#endif
+
 #endif /* _LINUX_NUMA_H */
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 4ae967bcf954..e2d8dd21ce9d 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -127,6 +127,36 @@  static struct mempolicy default_policy = {
 
 static struct mempolicy preferred_node_policy[MAX_NUMNODES];
 
+/**
+ * numa_map_to_online_node - Find closest online node
+ * @nid: Node id to start the search
+ *
+ * Lookup the next closest node by distance if @nid is not online.
+ */
+int numa_map_to_online_node(int node)
+{
+	int min_node;
+
+	if (node == NUMA_NO_NODE)
+		node = 0;
+
+	min_node = node;
+	if (!node_online(node)) {
+		int min_dist = INT_MAX, dist, n;
+
+		for_each_online_node(n) {
+			dist = node_distance(node, n);
+			if (dist < min_dist) {
+				min_dist = dist;
+				min_node = n;
+			}
+		}
+	}
+
+	return min_node;
+}
+EXPORT_SYMBOL_GPL(numa_map_to_online_node);
+
 struct mempolicy *get_task_policy(struct task_struct *p)
 {
 	struct mempolicy *pol = p->mempolicy;