diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2016-12-12 16:43:12 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-12 18:55:07 -0800 |
| commit | c1ef8e2c0235bffe4b0505c3325bb8a6af954021 (patch) | |
| tree | d4f4df30b5987170fda41b5af97df421bd8d7080 /include/linux/mempolicy.h | |
| parent | c7142aead87aa5026e4b57671c7dbb1706b02606 (diff) | |
mm: disable numa migration faults for dax vmas
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.
[akpm@linux-foundation.org: add comment]
Link: http://lkml.kernel.org/r/147892450132.22062.16875659431109209179.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/mempolicy.h')
| -rw-r--r-- | include/linux/mempolicy.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h index 5e5b2969d931..5f4d8281832b 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 +178,13 @@ static inline bool vma_migratable(struct vm_area_struct *vma) if (vma->vm_flags & (VM_IO | VM_PFNMAP)) return false; + /* + * DAX device mappings require predictable access latency, so avoid + * incurring periodic faults. + */ + if (vma_is_dax(vma)) + return false; + #ifndef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION if (vma->vm_flags & VM_HUGETLB) return false; |