+ mm-handle-hashdist-initialization-in-mm-mm_initc.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm: handle hashdist initialization in mm/mm_init.c
has been added to the -mm mm-unstable branch.  Its filename is
     mm-handle-hashdist-initialization-in-mm-mm_initc.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-handle-hashdist-initialization-in-mm-mm_initc.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Mike Rapoport (IBM)" <rppt@kernel.org>
Subject: mm: handle hashdist initialization in mm/mm_init.c
Date: Tue, 21 Mar 2023 19:05:03 +0200

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

Link: https://lkml.kernel.org/r/20230321170513.2401534-5-rppt@kernel.org
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Doug Berger <opendmb@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mm_init.c    |   22 ++++++++++++++++++++++
 mm/page_alloc.c |   18 ------------------
 2 files changed, 22 insertions(+), 18 deletions(-)

--- a/mm/mm_init.c~mm-handle-hashdist-initialization-in-mm-mm_initc
+++ a/mm/mm_init.c
@@ -607,6 +607,25 @@ int __meminit early_pfn_to_nid(unsigned
 
 	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
 	}
 
 	memmap_init();
+
+	/* disable hash distribution for systems with a single node */
+	fixup_hashdist();
 }
 
 /**
--- a/mm/page_alloc.c~mm-handle-hashdist-initialization-in-mm-mm_initc
+++ a/mm/page_alloc.c
@@ -6383,28 +6383,10 @@ static int page_alloc_cpu_online(unsigne
 	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,
_

Patches currently in -mm which might be from rppt@kernel.org are

mips-fix-comment-about-pgtable_init.patch
mm-page_alloc-add-helper-for-checking-if-check_pages_enabled.patch
mm-move-most-of-core-mm-initialization-to-mm-mm_initc.patch
mm-handle-hashdist-initialization-in-mm-mm_initc.patch
mm-page_alloc-rename-page_alloc_init-to-page_alloc_init_cpuhp.patch
init-fold-build_all_zonelists-and-page_alloc_init_cpuhp-to-mm_init.patch
initmm-move-mm_init-to-mm-mm_initc-and-rename-it-to-mm_core_init.patch
mm-call-ptlockpgtable_cache_init-directly-from-mm_core_init.patch
mm-move-init_mem_debugging_and_hardening-to-mm-mm_initc.patch
initmm-fold-late-call-to-page_ext_init-to-page_alloc_init_late.patch
mm-move-mem_init_print_info-to-mm_initc.patch
mm-move-kmem_cache_init-declaration-to-mm-slabh.patch
mm-move-vmalloc_init-declaration-to-mm-internalh.patch
maintainers-extend-memblock-entry-to-include-mm-initialization.patch