The patch titled Subject: mm/large system hash: avoid vmap for non-NUMA machines when hashdist has been added to the -mm tree. Its filename is mm-large-system-hash-avoid-vmap-for-non-numa-machines-when-hashdist.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-large-system-hash-avoid-vmap-for-non-numa-machines-when-hashdist.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-large-system-hash-avoid-vmap-for-non-numa-machines-when-hashdist.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Nicholas Piggin <npiggin@xxxxxxxxx> Subject: mm/large system hash: avoid vmap for non-NUMA machines when hashdist hashdist currently always uses vmalloc when hashdist is true. When there is only 1 online node and size <= MAX_ORDER, vmalloc can be avoided. Link: http://lkml.kernel.org/r/20190528120453.27374-2-npiggin@xxxxxxxxx Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx> Cc: Toshi Kani <toshi.kani@xxxxxx> Cc: Uladzislau Rezki <urezki@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/page_alloc.c~mm-large-system-hash-avoid-vmap-for-non-numa-machines-when-hashdist +++ a/mm/page_alloc.c @@ -8029,7 +8029,8 @@ void *__init alloc_large_system_hash(con else table = memblock_alloc_raw(size, SMP_CACHE_BYTES); - } else if (get_order(size) >= MAX_ORDER || hashdist) { + } else if (get_order(size) >= MAX_ORDER || + (hashdist && num_online_nodes() > 1)) { table = __vmalloc(size, gfp_flags, PAGE_KERNEL); } else { /* _ Patches currently in -mm which might be from npiggin@xxxxxxxxx are mm-large-system-hash-use-vmalloc-for-size-max_order-when-hashdist.patch mm-large-system-hash-avoid-vmap-for-non-numa-machines-when-hashdist.patch mm-move-ioremap-page-table-mapping-function-to-mm.patch mm-vmalloc-hugepage-vmalloc-mappings.patch