Mark dax vmas as not migratable to exclude them from task_numa_work(). This is especially relevant for device-dax which wants to ensure predictable access latency and not incur periodic faults.
Cc: Andrew Morton <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Reported-by: Aneesh Kumar K.V <[email protected]> Signed-off-by: Dan Williams <[email protected]> --- include/linux/mempolicy.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h index 5e5b2969d931..d72c691afaa6 100644 --- a/include/linux/mempolicy.h +++ b/include/linux/mempolicy.h @@ -7,6 +7,7 @@ #include <linux/mmzone.h> +#include <linux/dax.h> #include <linux/slab.h> #include <linux/rbtree.h> #include <linux/spinlock.h> @@ -177,6 +178,9 @@ static inline bool vma_migratable(struct vm_area_struct *vma) if (vma->vm_flags & (VM_IO | VM_PFNMAP)) return false; + if (vma_is_dax(vma)) + return false; + #ifndef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION if (vma->vm_flags & VM_HUGETLB) return false;
