Commit d645fc0e authored Jan 15, 2016 by Liang Chen Committed by Linus Torvalds Jan 15, 2016

mm: mempolicy: skip non-migratable VMAs when setting MPOL_MF_LAZY



MPOL_MF_LAZY is not visible from userspace since a720094d ("mm:
mempolicy: Hide MPOL_NOOP and MPOL_MF_LAZY from userspace for now"), but
it should still skip non-migratable VMAs such as VM_IO, VM_PFNMAP, and
VM_HUGETLB VMAs, and avoid useless overhead of minor faults.

Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Signed-off-by: Gavin Guo <gavin.guo@canonical.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent f16f091b

mm/mempolicy.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -644,7 +644,8 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end,

		if (flags & MPOL_MF_LAZY) {
		/* Similar to task_numa_work, skip inaccessible VMAs */
		if (vma->vm_flags & (VM_READ \| VM_EXEC \| VM_WRITE))
		if (vma_migratable(vma) &&
		vma->vm_flags & (VM_READ \| VM_EXEC \| VM_WRITE))
		change_prot_numa(vma, start, endvma);
		return 1;
		}

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