txt-mm-khugepaged-write-lock-vma-while-collapsing-a-huge-page-fix-fix

I missed vma_try_start_write() definition for CONFIG_PER_VMA_LOCK=n
configuration.

Link: https://lkml.kernel.org/r/CAJuCfpFjWhtzRE1X=J+_JjgJzNKhq-=JT8yTBSTHthwp0pqWZw@mail.gmail.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 8a981f0085f25940901dabc69e11d5a0a8143d66..d7ed0a36d750c4f0b37e3a155bc1f9db446ea50a 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -717,6 +717,8 @@ static inline bool vma_start_read(struct vm_area_struct *vma)
                { return false; }
 static inline void vma_end_read(struct vm_area_struct *vma) {}
 static inline void vma_start_write(struct vm_area_struct *vma) {}
+static inline bool vma_try_start_write(struct vm_area_struct *vma)
+               { return true; }
 static inline void vma_assert_write_locked(struct vm_area_struct *vma) {}
 
 #endif /* CONFIG_PER_VMA_LOCK */