linux/include
Muchun Song 6636109512 mm: memory_hotplug: make hugetlb_optimize_vmemmap compatible with memmap_on_memory
For now, the feature of hugetlb_free_vmemmap is not compatible with the
feature of memory_hotplug.memmap_on_memory, and hugetlb_free_vmemmap takes
precedence over memory_hotplug.memmap_on_memory.  However, someone wants
to make memory_hotplug.memmap_on_memory takes precedence over
hugetlb_free_vmemmap since memmap_on_memory makes it more likely to
succeed memory hotplug in close-to-OOM situations.  So the decision of
making hugetlb_free_vmemmap take precedence is not wise and elegant.

The proper approach is to have hugetlb_vmemmap.c do the check whether the
section which the HugeTLB pages belong to can be optimized.  If the
section's vmemmap pages are allocated from the added memory block itself,
hugetlb_free_vmemmap should refuse to optimize the vmemmap, otherwise, do
the optimization.  Then both kernel parameters are compatible.  So this
patch introduces VmemmapSelfHosted to mask any non-optimizable vmemmap
pages.  The hugetlb_vmemmap can use this flag to detect if a vmemmap page
can be optimized.

[songmuchun@bytedance.com: walk vmemmap page tables to avoid false-positive]
  Link: https://lkml.kernel.org/r/20220620110616.12056-3-songmuchun@bytedance.com
Link: https://lkml.kernel.org/r/20220617135650.74901-3-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Co-developed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-03 18:08:49 -07:00
..
acpi
asm-generic kernel: add platform_has() infrastructure 2022-06-06 08:06:00 +02:00
clocksource pwm: Changes for v5.19-rc1 2022-06-01 10:49:11 -07:00
crypto
drm drm/ttm: fix bulk move handling v2 2022-06-14 11:15:19 +02:00
dt-bindings Char / Misc / Other smaller driver subsystem updates for 5.19-rc1 2022-06-03 11:36:34 -07:00
keys certs: Move load_certificate_list() to be with the asymmetric keys code 2022-06-21 16:05:06 +01:00
kunit
kvm
linux mm: memory_hotplug: make hugetlb_optimize_vmemmap compatible with memmap_on_memory 2022-07-03 18:08:49 -07:00
math-emu
media
memory
misc
net sock: redo the psock vs ULP protection check 2022-06-23 10:08:30 +02:00
pcmcia
ras
rdma
scsi
soc
sound ARM: multiplatform changes, part 2 2022-06-02 15:23:54 -07:00
target
trace ATA fixes for 5.19-rc4 2022-06-24 11:12:34 -07:00
uapi io_uring: remove IORING_CLOSE_FD_AND_FILE_SLOT 2022-06-14 10:57:40 -06:00
ufs
vdso
video
xen arm/xen: Assign xen-grant DMA ops for xen-grant DMA devices 2022-06-06 16:07:30 +02:00