linux/include
Yang Shi b265cdebdf sched: coredump.h: clarify the use of MMF_VM_HUGEPAGE
Patch series "Make khugepaged collapse readonly FS THP more consistent", v4.

The readonly FS THP relies on khugepaged to collapse THP for suitable
vmas.  But the behavior is inconsistent for "always" mode
(https://lore.kernel.org/linux-mm/00f195d4-d039-3cf2-d3a1-a2c88de397a0@suse.cz/).

The "always" mode means THP allocation should be tried all the time and
khugepaged should try to collapse THP all the time.  Of course the
allocation and collapse may fail due to other factors and conditions.

Currently file THP may not be collapsed by khugepaged even though all the
conditions are met.  That does break the semantics of "always" mode.

So make sure readonly FS vmas are registered to khugepaged to fix the
break.

Register suitable vmas in common mmap path, that could cover both readonly
FS vmas and shmem vmas, so remove the khugepaged calls in shmem.c.

The patch 1-7 are minor bug fixes, clean up and preparation patches. 
Patch 8 is the real meat.  

Tested with khugepaged test in selftests and the testcase provided by
Vlastimil Babka in
https://lore.kernel.org/lkml/df3b5d1c-a36b-2c73-3e27-99e74983de3a@suse.cz/
by commenting out MADV_HUGEPAGE call.


This patch (of 8):

MMF_VM_HUGEPAGE is set as long as the mm is available for khugepaged by
khugepaged_enter(), not only when VM_HUGEPAGE is set on vma.  Correct the
comment to avoid confusion.

Link: https://lkml.kernel.org/r/20220510203222.24246-1-shy828301@gmail.com
Link: https://lkml.kernel.org/r/20220510203222.24246-2-shy828301@gmail.com
Signed-off-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Vlastmil Babka <vbabka@suse.cz>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-19 14:08:48 -07:00
..
acpi ACPI: bus: Eliminate acpi_bus_get_device() 2022-04-05 19:49:26 +02:00
asm-generic riscv/mm: fix two page table check related issues 2022-05-19 14:08:48 -07:00
clocksource
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2022-03-21 16:02:36 -07:00
drm
dt-bindings RTC for 5.18 2022-04-01 09:37:18 -07:00
keys
kunit
kvm
linux sched: coredump.h: clarify the use of MMF_VM_HUGEPAGE 2022-05-19 14:08:48 -07:00
math-emu
media
memory
misc
net bluetooth pull request for net: 2022-04-28 10:18:51 +02:00
pcmcia
ras Revert "mm/memory-failure.c: fix race with changing page compound again" 2022-04-28 23:16:02 -07:00
rdma
scsi scsi: iscsi: Fix NOP handling during conn recovery 2022-04-11 22:09:35 -04:00
soc drm for 5.18-rc1 2022-03-24 16:19:43 -07:00
sound ASoC: Fixes for v5.18 2022-04-19 17:26:01 +02:00
target
trace tracing: incorrect gfp_t conversion 2022-05-13 07:20:18 -07:00
uapi mm/uffd: enable write protection for shmem & hugetlbfs 2022-05-13 07:20:11 -07:00
vdso
video
xen