linux.git/mm/mm_init.c, branch v6.7

mm: hugetlb: skip initialization of gigantic tail struct pages if freed by HVO

2023-10-04T17:32:30+00:00

The new boot flow when it comes to initialization of gigantic pages is as
follows:

- At boot time, for a gigantic page during __alloc_bootmem_hugepage, the
  region after the first struct page is marked as noinit.

- This results in only the first struct page to be initialized in
  reserve_bootmem_region.  As the tail struct pages are not initialized at
  this point, there can be a significant saving in boot time if HVO
  succeeds later on.

- Later on in the boot, the head page is prepped and the first
  HUGETLB_VMEMMAP_RESERVE_SIZE / sizeof(struct page) - 1 tail struct pages
  are initialized.

- HVO is attempted.  If it is not successful, then the rest of the tail
  struct pages are initialized.  If it is successful, no more tail struct
  pages need to be initialized saving significant boot time.

The WARN_ON for increased ref count in gather_bootmem_prealloc was changed
to a VM_BUG_ON.  This is OK as there should be no speculative references
this early in boot process.  The VM_BUG_ON's are there just in case such
code is introduced.

[akpm@linux-foundation.org: make it nicer for 80 cols]
Link: https://lkml.kernel.org/r/20230913105401.519709-5-usama.arif@bytedance.com
Signed-off-by: Usama Arif 
Reviewed-by: Muchun Song 
Reviewed-by: Mike Kravetz 
Cc: Fam Zheng 
Cc: Mike Rapoport (IBM) 
Cc: Punit Agrawal 
Signed-off-by: Andrew Morton

mm/mm_init.c: remove redundant pr_info when node is memoryless

2023-10-04T17:32:22+00:00

There is a similar pr_info in free_area_init_node(), so remove the
redundant pr_info.

before:
[    0.006314] Initializing node 0 as memoryless
[    0.006445] Initmem setup node 0 as memoryless
[    0.006450] Initmem setup node 1 [mem 0x0000000000001000-0x000000003fffffff]
[    0.006453] Initmem setup node 2 [mem 0x0000000040000000-0x000000007ffd7fff]
[    0.006454] Initializing node 3 as memoryless
[    0.006584] Initmem setup node 3 as memoryless
[    0.006585] Initmem setup node 4 [mem 0x0000000100000000-0x00000001bfffffff]
[    0.006586] Initmem setup node 5 [mem 0x00000001c0000000-0x00000001ffffffff]
[    0.006587] Initmem setup node 6 [mem 0x0000000200000000-0x000000023fffffff]

after:
[    0.004147] Initmem setup node 0 as memoryless
[    0.004148] Initmem setup node 1 [mem 0x0000000000001000-0x000000003fffffff]
[    0.004150] Initmem setup node 2 [mem 0x0000000040000000-0x000000007ffd7fff]
[    0.004154] Initmem setup node 3 as memoryless
[    0.004155] Initmem setup node 4 [mem 0x0000000100000000-0x00000001bfffffff]
[    0.004156] Initmem setup node 5 [mem 0x00000001c0000000-0x00000001ffffffff]
[    0.004157] Initmem setup node 6 [mem 0x0000000200000000-0x000000023fffffff]

Link: https://lkml.kernel.org/r/20230906091113.4029983-1-yajun.deng@linux.dev
Signed-off-by: Yajun Deng 
Reviewed-by: David Hildenbrand 
Cc: Mike Rapoport (IBM) 
Signed-off-by: Andrew Morton

mm/mm_init: use helper macro BITS_PER_LONG and BITS_PER_BYTE

2023-08-21T20:37:47+00:00

It's more readable to use helper macro BITS_PER_LONG and BITS_PER_BYTE. 
No functional change intended.

Link: https://lkml.kernel.org/r/20230807023528.325191-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin 
Reviewed-by: David Hildenbrand 
Reviewed-by: Mike Rapoport (IBM) 
Signed-off-by: Andrew Morton

mm: disable kernelcore=mirror when no mirror memory

2023-08-21T20:37:43+00:00

For system with kernelcore=mirror enabled while no mirrored memory is
reported by efi.  This could lead to kernel OOM during startup since all
memory beside zone DMA are in the movable zone and this prevents the
kernel to use it.

Zone DMA/DMA32 initialization is independent of mirrored memory and their
max pfn is set in zone_sizes_init().  Since kernel can fallback to zone
DMA/DMA32 if there is no memory in zone Normal, these zones are seen as
mirrored memory no mather their memory attributes are.

To solve this problem, disable kernelcore=mirror when there is no real
mirrored memory exists.

Link: https://lkml.kernel.org/r/20230802072328.2107981-1-mawupeng1@huawei.com
Signed-off-by: Ma Wupeng 
Suggested-by: Kefeng Wang 
Suggested-by: Mike Rapoport 
Reviewed-by: Mike Rapoport (IBM) 
Reviewed-by: Kefeng Wang 
Cc: Levi Yun 
Signed-off-by: Andrew Morton

mm: no need to export mm_kobj

2023-08-21T20:37:40+00:00

There are no modules using mm_kobj, so do not export it.

Link: https://lkml.kernel.org/r/2023080436-algebra-cabana-417d@gregkh
Signed-off-by: Greg Kroah-Hartman 
Reviewed-by: Mike Rapoport (IBM) 
Reviewed-by: Miaohe Lin 
Reviewed-by: David Hildenbrand 
Signed-off-by: Andrew Morton

mm/vmemmap: improve vmemmap_can_optimize and allow architectures to override

2023-08-18T17:12:53+00:00

dax vmemmap optimization requires a minimum of 2 PAGE_SIZE area within
vmemmap such that tail page mapping can point to the second PAGE_SIZE
area.  Enforce that in vmemmap_can_optimize() function.

Architectures like powerpc also want to enable vmemmap optimization
conditionally (only with radix MMU translation).  Hence allow architecture
override.

Link: https://lkml.kernel.org/r/20230724190759.483013-4-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V 
Reviewed-by: Christophe Leroy 
Cc: Catalin Marinas 
Cc: Dan Williams 
Cc: Joao Martins 
Cc: Michael Ellerman 
Cc: Mike Kravetz 
Cc: Muchun Song 
Cc: Nicholas Piggin 
Cc: Oscar Salvador 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

mm: kfence: allocate kfence_metadata at runtime

2023-08-18T17:12:39+00:00

kfence_metadata is currently a static array.  For the purpose of
allocating scalable __kfence_pool, we first change it to runtime
allocation of metadata.  Since the size of an object of kfence_metadata is
1160 bytes, we can save at least 72 pages (with default 256 objects)
without enabling kfence.

[akpm@linux-foundation.org: restore newline, per Marco]
Link: https://lkml.kernel.org/r/20230718073019.52513-1-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang 
Reviewed-by: Marco Elver 
Cc: Alexander Potapenko 
Cc: Dmitry Vyukov 
Cc: Muchun Song 
Signed-off-by: Andrew Morton

mm/mm_init.c: drop node_start_pfn from adjust_zone_range_for_zone_movable()

2023-08-18T17:12:37+00:00

node_start_pfn is not used in adjust_zone_range_for_zone_movable(), so it
is pointless to waste a function argument.  Drop the parameter.

Link: https://lkml.kernel.org/r/20230717065811.1262-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu 
Reviewed-by: David Hildenbrand 
Reviewed-by: Mike Rapoport (IBM) 
Reviewed-by: Anshuman Khandual 
Signed-off-by: Andrew Morton

mm/mm_init.c: mark check_for_memory() as __init

2023-08-18T17:12:18+00:00

The only caller of check_for_memory() is free_area_init(), which is
annotated with __init, so it should be safe to also mark the former as
__init.

Link: https://lkml.kernel.org/r/20230710093750.1294-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu 
Reviewed-by: Mike Rapoport (IBM) 
Reviewed-by: Anshuman Khandual 
Signed-off-by: Andrew Morton

mm/mm_init.c: remove obsolete macro HASH_SMALL

2023-08-18T17:12:07+00:00

HASH_SMALL only works when parameter numentries is 0. But the sole caller
futex_init() never calls alloc_large_system_hash() with numentries set to
0. So HASH_SMALL is obsolete and remove it.

Link: https://lkml.kernel.org/r/20230625021323.849147-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin 
Reviewed-by: Mike Rapoport (IBM) 
Cc: André Almeida 
Cc: Darren Hart 
Cc: Davidlohr Bueso 
Cc: Ingo Molnar 
Cc: Miaohe Lin 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Signed-off-by: Andrew Morton