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Percpu embedded first chunk allocator is the firstly option, but it
could fails on ARM64, eg,

  percpu: max_distance=0x5fcfdc640000 too large for vmalloc space 0x781fefff0000
  percpu: max_distance=0x600000540000 too large for vmalloc space 0x7dffb7ff0000
  percpu: max_distance=0x5fff9adb0000 too large for vmalloc space 0x5dffb7ff0000

then we could get

  WARNING: CPU: 15 PID: 461 at vmalloc.c:3087 pcpu_get_vm_areas+0x488/0x838

and the system could not boot successfully.

Let's implement page mapping percpu first chunk allocator as a fallback
to the embedding allocator to increase the robustness of the system.

Link: https://lkml.kernel.org/r/20210910053354.26721-3-wangkefeng.wang@huawei.com

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>