linux/include
Frank van der Linden d65917c423 mm/sparse: allow for alternate vmemmap section init at boot
Add functions that are called just before the per-section memmap is
initialized and just before the memmap page structures are initialized. 
They are called sparse_vmemmap_init_nid_early and
sparse_vmemmap_init_nid_late, respectively.

This allows for mm subsystems to add calls to initialize memmap and page
structures in a specific way, if using SPARSEMEM_VMEMMAP.  Specifically,
hugetlb can pre-HVO bootmem allocated pages that way, so that no time and
resources are wasted on allocating vmemmap pages, only to free them later
(and possibly unnecessarily running the system out of memory in the
process).

Refactor some code and export a few convenience functions for external
use.

In sparse_init_nid, skip any sections that are already initialized, e.g. 
they have been initialized by sparse_vmemmap_init_nid_early already.

The hugetlb code to use these functions will be added in a later commit.

Export section_map_size, as any alternate memmap init code will want to
use it.

The internal config option to enable this is SPARSEMEM_VMEMMAP_PREINIT,
which is selected if an architecture-specific option,
ARCH_WANT_HUGETLB_VMEMMAP_PREINIT, is set.  In the future, if other
subsystems want to do preinit too, they can do it in a similar fashion.

The internal config option is there because a section flag is used, and
the number of flags available is architecture-dependent (see mmzone.h). 
Architecures can decide if there is room for the flag when enabling
options that select SPARSEMEM_VMEMMAP_PREINIT.

Fortunately, as of right now, all sparse vmemmap using architectures do
have room.

Link: https://lkml.kernel.org/r/20250228182928.2645936-11-fvdl@google.com
Signed-off-by: Frank van der Linden <fvdl@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin (Cruise) <roman.gushchin@linux.dev>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
History 2025-03-16 22:06:27 -07:00
..
acpi LoongArch changes for v6.14 2025-01-28 08:52:01 -08:00
asm-generic mm/ioremap: pass pgprot_t to ioremap_prot() instead of unsigned long 2025-03-16 22:06:23 -07:00
clocksource KVM/arm64 updates for 6.14 2025-01-28 09:01:36 -08:00
crypto crypto: skcipher - document skcipher_walk_done() and rename some vars 2025-01-14 11:38:32 +08:00
cxl cxl/events: Update Memory Module Event Record to CXL spec rev 3.1 2025-01-13 09:33:21 -07:00
drm drm: Fix DSC BPP increment decoding 2025-02-13 10:20:30 +02:00
dt-bindings dt-bindings: clock: qcom: Add CAMCC clocks for QCS8300 2025-02-02 20:59:04 -06:00
hyperv hyperv: Add new Hyper-V headers in include/hyperv 2025-01-10 00:54:20 +00:00
keys keys: drop shadowing dead prototype 2025-01-21 11:25:23 +02:00
kunit linux_kselftest-kunit-6.14-rc1 2025-01-22 12:32:39 -08:00
kvm Merge branch kvm-arm64/pkvm-memshare-declutter into kvmarm-master/next 2025-01-17 11:05:18 +00:00
linux mm/sparse: allow for alternate vmemmap section init at boot 2025-03-16 22:06:27 -07:00
math-emu powerpc/math-emu: Remove -w build flag and fix warnings 2022-09-05 17:28:25 +10:00
media media: cec: include linux/debugfs.h and linux/seq_file.h where needed 2025-01-07 12:21:38 +01:00
memory memory: renesas-rpc-if: Remove Runtime PM wrappers 2023-01-23 11:48:00 +01:00
misc cxl: fix typo in comment 2022-11-24 23:12:19 +11:00
net percpu: use TYPEOF_UNQUAL() in variable declarations 2025-03-16 22:05:53 -07:00
pcmcia ARM: pxa/sa1100: move I/O space to PCI_IOBASE 2022-05-07 22:56:17 +02:00
ras mm/memory-failure: remove obsolete MF_MSG_DIFFERENT_COMPOUND 2024-07-12 15:52:22 -07:00
rdma RDMA/core: Support link status events dispatching 2024-12-24 05:22:18 -05:00
rv rv: Reset per-task monitors also for idle tasks 2025-01-23 12:16:04 -05:00
scsi Driver core and debugfs updates 2025-01-28 12:25:12 -08:00
soc soc: driver updates for 6.14 2025-01-24 14:56:59 -08:00
sound ASoC: cs35l56: Prevent races when soft-resetting using SPI control 2025-02-25 15:06:58 +00:00
target scsi: target: iscsi: switch to using the crc32c library 2024-12-01 17:23:02 -08:00
trace Including fixes from bluetooth. We didn't get netfilter or wireless PRs 2025-02-27 09:32:42 -08:00
uapi Landlock fix for v6.14-rc5 2025-02-26 11:55:44 -08:00
ufs scsi: ufs: core: Fix use-after free in init error and remove paths 2025-02-03 17:20:01 -05:00
vdso vdso: Correct typo in PAGE_SHIFT comment 2025-01-15 11:07:08 +01:00
video - Improved handling of LCD power states and interactions with the fbdev subsystem. 2024-11-22 16:29:57 -08:00
xen xen: Remove dependency between pciback and privcmd 2024-10-18 11:59:04 +02:00