[PATCH v2 04/14] mm: handle hashdist initialization in mm/mm_init.c

From: Mike Rapoport
Date: Tue Mar 21 2023 - 13:06:23 EST


From: "Mike Rapoport (IBM)" <rppt@xxxxxxxxxx>

The hashdist variable must be initialized before the first call to
alloc_large_system_hash() and free_area_init() looks like a better place
for it than page_alloc_init().

Move hashdist handling to mm/mm_init.c

Signed-off-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
---
mm/mm_init.c | 22 ++++++++++++++++++++++
mm/page_alloc.c | 18 ------------------
2 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/mm/mm_init.c b/mm/mm_init.c
index 68d0187c7886..2e60c7186132 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -607,6 +607,25 @@ int __meminit early_pfn_to_nid(unsigned long pfn)

return nid;
}
+
+int hashdist = HASHDIST_DEFAULT;
+
+static int __init set_hashdist(char *str)
+{
+ if (!str)
+ return 0;
+ hashdist = simple_strtoul(str, &str, 0);
+ return 1;
+}
+__setup("hashdist=", set_hashdist);
+
+static inline void fixup_hashdist(void)
+{
+ if (num_node_state(N_MEMORY) == 1)
+ hashdist = 0;
+}
+#else
+static inline void fixup_hashdist(void) {}
#endif /* CONFIG_NUMA */

#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
@@ -1855,6 +1874,9 @@ void __init free_area_init(unsigned long *max_zone_pfn)
}

memmap_init();
+
+ /* disable hash distribution for systems with a single node */
+ fixup_hashdist();
}

/**
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index c56c147bdf27..ff6a2fff2880 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6383,28 +6383,10 @@ static int page_alloc_cpu_online(unsigned int cpu)
return 0;
}

-#ifdef CONFIG_NUMA
-int hashdist = HASHDIST_DEFAULT;
-
-static int __init set_hashdist(char *str)
-{
- if (!str)
- return 0;
- hashdist = simple_strtoul(str, &str, 0);
- return 1;
-}
-__setup("hashdist=", set_hashdist);
-#endif
-
void __init page_alloc_init(void)
{
int ret;

-#ifdef CONFIG_NUMA
- if (num_node_state(N_MEMORY) == 1)
- hashdist = 0;
-#endif
-
ret = cpuhp_setup_state_nocalls(CPUHP_PAGE_ALLOC,
"mm/page_alloc:pcp",
page_alloc_cpu_online,
--
2.35.1