hugetlb: add support for preferred node to alloc_huge_page_nodemask
authorMichal Hocko <mhocko@suse.com>
Mon, 10 Jul 2017 22:49:11 +0000 (15:49 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 10 Jul 2017 23:32:32 +0000 (16:32 -0700)
commit3e59fcb0e8c1c40aecb60fa4c2d1543d6a097184
treeca74d84f09c46bb218560d44af6da809cc313dfe
parentaaf14e40a33a2c9350471387031ca40c00f5a006
hugetlb: add support for preferred node to alloc_huge_page_nodemask

alloc_huge_page_nodemask tries to allocate from any numa node in the
allowed node mask starting from lower numa nodes.  This might lead to
filling up those low NUMA nodes while others are not used.  We can
reduce this risk by introducing a concept of the preferred node similar
to what we have in the regular page allocator.  We will start allocating
from the preferred nid and then iterate over all allowed nodes in the
zonelist order until we try them all.

This is mimicing the page allocator logic except it operates on per-node
mempools.  dequeue_huge_page_vma already does this so distill the
zonelist logic into a more generic dequeue_huge_page_nodemask and use it
in alloc_huge_page_nodemask.

This will allow us to use proper per numa distance fallback also for
alloc_huge_page_node which can use alloc_huge_page_nodemask now and we
can get rid of alloc_huge_page_node helper which doesn't have any user
anymore.

Link: http://lkml.kernel.org/r/20170622193034.28972-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Tested-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/hugetlb.h
include/linux/migrate.h
mm/hugetlb.c