mm/vmalloc: fix numa spreading for large hash tables

mm/vmalloc: fix numa spreading for large hash tables

Eric Dumazet reported a strange numa spreading info in [1], and found
commit 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings") introduced
this issue [2].

Dig into the difference before and after this patch, page allocation has
some difference:

before:
  alloc_large_system_hash
    __vmalloc
      __vmalloc_node(..., NUMA_NO_NODE, ...)
        __vmalloc_node_range
          __vmalloc_area_node
            alloc_page /* because NUMA_NO_NODE, so choose alloc_page branch */
              alloc_pages_current
                alloc_page_interleave /* can be proved by print policy mode */

after:
  alloc_large_system_hash
    __vmalloc
      __vmalloc_node(..., NUMA_NO_NODE, ...)
        __vmalloc_node_range
          __vmalloc_area_node
            alloc_pages_node /* choose nid by nuam_mem_id() */
              __alloc_pages_node(nid, ....)

So after commit 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings"),
it will allocate memory in current node instead of interleaving allocate
memory.

Link: https://lore.kernel.org/linux-mm/CANn89iL6AAyWhfxdHO+jaT075iOa3XcYn9k6JJc7JR2XYn6k_Q@mail.gmail.com/
Link: https://lore.kernel.org/linux-mm/CANn89iLofTR=AK-QOZY87RdUZENCZUT4O6a0hvhu3_EwRMerOg@mail.gmail.com/
Link: https://lkml.kernel.org/r/[email protected]
Fixes: 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings")
Signed-off-by: Chen Wandun <[email protected]>
Reported-by: Eric Dumazet <[email protected]>
Cc: Shakeel Butt <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Kefeng Wang <[email protected]>
Cc: Hanjun Guo <[email protected]>
Cc: Uladzislau Rezki <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>