[PATCH v2 33/69] mm/sparse: Remove SPARSEMEM_VMEMMAP_PREINIT
From: Muchun Song
Date: Wed May 13 2026 - 09:20:12 EST
SPARSEMEM_VMEMMAP_PREINIT was only there to support HugeTLB's early
vmemmap optimization setup.
Now that HugeTLB bootmem vmemmap optimization uses the common
section-based sparse-vmemmap path, sparsemem no longer needs a separate
pre-initialization mechanism.
Remove the Kconfig symbols, section flag, and empty sparse-vmemmap early
hook, and always initialize present sections through the normal sparse
setup path.
Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
arch/x86/Kconfig | 1 -
fs/Kconfig | 1 -
include/linux/mmzone.h | 25 -------------------------
mm/Kconfig | 5 -----
mm/sparse-vmemmap.c | 13 -------------
mm/sparse.c | 23 ++++++++---------------
6 files changed, 8 insertions(+), 60 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index f24810015234..ed2aa0e4c472 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -148,7 +148,6 @@ config X86
select ARCH_WANT_LD_ORPHAN_WARN
select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP if X86_64
select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP if X86_64
- select ARCH_WANT_HUGETLB_VMEMMAP_PREINIT if X86_64
select ARCH_WANTS_THP_SWAP if X86_64
select ARCH_HAS_PARANOID_L1D_FLUSH
select ARCH_WANT_IRQS_OFF_ACTIVATE_MM
diff --git a/fs/Kconfig b/fs/Kconfig
index cf6ae64776e6..ccb9dd480523 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -278,7 +278,6 @@ config HUGETLB_PAGE_OPTIMIZE_VMEMMAP
def_bool HUGETLB_PAGE
depends on ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
depends on SPARSEMEM_VMEMMAP
- select SPARSEMEM_VMEMMAP_PREINIT if ARCH_WANT_HUGETLB_VMEMMAP_PREINIT
config HUGETLB_PMD_PAGE_TABLE_SHARING
def_bool HUGETLB_PAGE
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index d6a5dd042c25..b9baef8cca91 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -2092,9 +2092,6 @@ enum {
SECTION_IS_EARLY_BIT,
#ifdef CONFIG_ZONE_DEVICE
SECTION_TAINT_ZONE_DEVICE_BIT,
-#endif
-#ifdef CONFIG_SPARSEMEM_VMEMMAP_PREINIT
- SECTION_IS_VMEMMAP_PREINIT_BIT,
#endif
SECTION_MAP_LAST_BIT,
};
@@ -2106,9 +2103,6 @@ enum {
#ifdef CONFIG_ZONE_DEVICE
#define SECTION_TAINT_ZONE_DEVICE BIT(SECTION_TAINT_ZONE_DEVICE_BIT)
#endif
-#ifdef CONFIG_SPARSEMEM_VMEMMAP_PREINIT
-#define SECTION_IS_VMEMMAP_PREINIT BIT(SECTION_IS_VMEMMAP_PREINIT_BIT)
-#endif
#define SECTION_MAP_MASK (~(BIT(SECTION_MAP_LAST_BIT) - 1))
#define SECTION_NID_SHIFT SECTION_MAP_LAST_BIT
@@ -2163,24 +2157,6 @@ static inline int online_device_section(const struct mem_section *section)
}
#endif
-#ifdef CONFIG_SPARSEMEM_VMEMMAP_PREINIT
-static inline int preinited_vmemmap_section(const struct mem_section *section)
-{
- return (section &&
- (section->section_mem_map & SECTION_IS_VMEMMAP_PREINIT));
-}
-
-void sparse_vmemmap_init_nid_early(int nid);
-#else
-static inline int preinited_vmemmap_section(const struct mem_section *section)
-{
- return 0;
-}
-static inline void sparse_vmemmap_init_nid_early(int nid)
-{
-}
-#endif
-
static inline int online_section_nr(unsigned long nr)
{
return online_section(__nr_to_section(nr));
@@ -2427,7 +2403,6 @@ static inline unsigned long next_present_section_nr(unsigned long section_nr)
#endif
#else
-#define sparse_vmemmap_init_nid_early(_nid) do {} while (0)
#define pfn_in_present_section pfn_valid
static inline void section_set_order_range(unsigned long pfn, unsigned long nr_pages,
unsigned int order)
diff --git a/mm/Kconfig b/mm/Kconfig
index bb0202cf8b15..c26d2d2050d5 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -410,8 +410,6 @@ config SPARSEMEM_VMEMMAP
pfn_to_page and page_to_pfn operations. This is the most
efficient option when sufficient kernel resources are available.
-config SPARSEMEM_VMEMMAP_PREINIT
- bool
#
# Select this config option from the architecture Kconfig, if it is preferred
# to enable the feature of HugeTLB/dev_dax vmemmap optimization.
@@ -422,9 +420,6 @@ config ARCH_WANT_OPTIMIZE_DAX_VMEMMAP
config ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
bool
-config ARCH_WANT_HUGETLB_VMEMMAP_PREINIT
- bool
-
config HAVE_MEMBLOCK_PHYS_MAP
bool
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index f1c3b2d0f23c..dde4486195ad 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -548,19 +548,6 @@ struct page * __meminit __populate_section_memmap(unsigned long pfn,
return pfn_to_page(pfn);
}
-#ifdef CONFIG_SPARSEMEM_VMEMMAP_PREINIT
-/*
- * This is called just before initializing sections for a NUMA node.
- * Any special initialization that needs to be done before the
- * generic initialization can be done from here. Sections that
- * are initialized in hooks called from here will be skipped by
- * the generic initialization.
- */
-void __init sparse_vmemmap_init_nid_early(int nid)
-{
-}
-#endif
-
static void subsection_mask_set(unsigned long *map, unsigned long pfn,
unsigned long nr_pages)
{
diff --git a/mm/sparse.c b/mm/sparse.c
index 47349f6f463f..eab37504819d 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -316,27 +316,20 @@ static void __init sparse_init_nid(int nid, unsigned long pnum_begin,
if (sparse_usage_init(nid, map_count))
panic("Failed to allocate usemap for node %d\n", nid);
- sparse_vmemmap_init_nid_early(nid);
-
for_each_present_section_nr(pnum_begin, pnum) {
- struct mem_section *ms;
unsigned long pfn = section_nr_to_pfn(pnum);
+ struct page *map;
if (pnum >= pnum_end)
break;
- ms = __nr_to_section(pnum);
- if (!preinited_vmemmap_section(ms)) {
- struct page *map;
-
- map = __populate_section_memmap(pfn, PAGES_PER_SECTION,
- nid, NULL, NULL);
- if (!map)
- panic("Failed to allocate memmap for section %lu\n", pnum);
- memmap_boot_pages_add(section_nr_vmemmap_pages(pfn, PAGES_PER_SECTION,
- NULL, NULL));
- sparse_init_early_section(nid, map, pnum, 0);
- }
+ map = __populate_section_memmap(pfn, PAGES_PER_SECTION,
+ nid, NULL, NULL);
+ if (!map)
+ panic("Failed to allocate memmap for section %lu\n", pnum);
+ memmap_boot_pages_add(section_nr_vmemmap_pages(pfn, PAGES_PER_SECTION,
+ NULL, NULL));
+ sparse_init_early_section(nid, map, pnum, 0);
}
sparse_usage_fini();
}
--
2.54.0