mm: untangle config dependencies for demote-on-reclaim
At the time demote-on-reclaim was introduced, it was tied to
CONFIG_HOTPLUG_CPU + CONFIG_MIGRATE, but that is not really accurate.
The only two things we need to depend on are CONFIG_NUMA + CONFIG_MIGRATE,
so clean this up. Furthermore, we only register the hotplug memory
notifier when the system has CONFIG_MEMORY_HOTPLUG.
Link: https://lkml.kernel.org/r/20220322224016.4574-1-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Suggested-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Abhishek Goel <huntbag@linux.vnet.ibm.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 90e75d5..2707bfd 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -47,16 +47,7 @@ void folio_migrate_copy(struct folio *newfolio, struct folio *folio);
int folio_migrate_mapping(struct address_space *mapping,
struct folio *newfolio, struct folio *folio, int extra_count);
-extern bool numa_demotion_enabled;
-extern void migrate_on_reclaim_init(void);
-#ifdef CONFIG_HOTPLUG_CPU
-extern void set_migration_target_nodes(void);
#else
-static inline void set_migration_target_nodes(void) {}
-#endif
-#else
-
-static inline void set_migration_target_nodes(void) {}
static inline void putback_movable_pages(struct list_head *l) {}
static inline int migrate_pages(struct list_head *l, new_page_t new,
@@ -82,9 +73,23 @@ static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
return -ENOSYS;
}
-#define numa_demotion_enabled false
#endif /* CONFIG_MIGRATION */
+#if defined(CONFIG_MIGRATION) && defined(CONFIG_NUMA)
+extern void set_migration_target_nodes(void);
+extern void migrate_on_reclaim_init(void);
+extern bool numa_demotion_enabled;
+extern int next_demotion_node(int node);
+#else
+static inline void set_migration_target_nodes(void) {}
+static inline void migrate_on_reclaim_init(void) {}
+static inline int next_demotion_node(int node)
+{
+ return NUMA_NO_NODE;
+}
+#define numa_demotion_enabled false
+#endif
+
#ifdef CONFIG_COMPACTION
extern int PageMovable(struct page *page);
extern void __SetPageMovable(struct page *page, struct address_space *mapping);
@@ -172,15 +177,6 @@ struct migrate_vma {
int migrate_vma_setup(struct migrate_vma *args);
void migrate_vma_pages(struct migrate_vma *migrate);
void migrate_vma_finalize(struct migrate_vma *migrate);
-int next_demotion_node(int node);
-
-#else /* CONFIG_MIGRATION disabled: */
-
-static inline int next_demotion_node(int node)
-{
- return NUMA_NO_NODE;
-}
-
#endif /* CONFIG_MIGRATION */
#endif /* _LINUX_MIGRATE_H */
diff --git a/mm/migrate.c b/mm/migrate.c
index f97d724..7759228 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2104,7 +2104,6 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
return 0;
}
#endif /* CONFIG_NUMA_BALANCING */
-#endif /* CONFIG_NUMA */
/*
* node_demotion[] example:
@@ -2238,7 +2237,6 @@ int next_demotion_node(int node)
return target;
}
-#if defined(CONFIG_HOTPLUG_CPU)
/* Disable reclaim-based migration. */
static void __disable_all_migrate_targets(void)
{
@@ -2431,6 +2429,7 @@ void set_migration_target_nodes(void)
* __set_migration_target_nodes() can be used as opposed to
* set_migration_target_nodes().
*/
+#ifdef CONFIG_MEMORY_HOTPLUG
static int __meminit migrate_on_reclaim_callback(struct notifier_block *self,
unsigned long action, void *_arg)
{
@@ -2476,6 +2475,7 @@ static int __meminit migrate_on_reclaim_callback(struct notifier_block *self,
return notifier_from_errno(0);
}
+#endif
void __init migrate_on_reclaim_init(void)
{
@@ -2483,8 +2483,9 @@ void __init migrate_on_reclaim_init(void)
sizeof(struct demotion_nodes),
GFP_KERNEL);
WARN_ON(!node_demotion);
-
+#ifdef CONFIG_MEMORY_HOTPLUG
hotplug_memory_notifier(migrate_on_reclaim_callback, 100);
+#endif
/*
* At this point, all numa nodes with memory/CPus have their state
* properly set, so we can build the demotion order now.
@@ -2495,7 +2496,6 @@ void __init migrate_on_reclaim_init(void)
set_migration_target_nodes();
cpus_read_unlock();
}
-#endif /* CONFIG_HOTPLUG_CPU */
bool numa_demotion_enabled = false;
@@ -2556,4 +2556,5 @@ static int __init numa_init_sysfs(void)
return err;
}
subsys_initcall(numa_init_sysfs);
-#endif
+#endif /* CONFIG_SYSFS */
+#endif /* CONFIG_NUMA */
diff --git a/mm/vmstat.c b/mm/vmstat.c
index b75b1a6..f2d0dec 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -2111,9 +2111,7 @@ void __init init_mm_internals(void)
start_shepherd_timer();
#endif
-#if defined(CONFIG_MIGRATION) && defined(CONFIG_HOTPLUG_CPU)
migrate_on_reclaim_init();
-#endif
#ifdef CONFIG_PROC_FS
proc_create_seq("buddyinfo", 0444, NULL, &fragmentation_op);
proc_create_seq("pagetypeinfo", 0400, NULL, &pagetypeinfo_op);
