[PATCH 2/3] mm: huge_memory: add thp_vma_disabled()

[Kefeng Wang <wangkefeng.wang@huawei.com>]

Add thp_vma_disabled() helper to shared by shmem_allowable_huge_orders()
and __thp_vma_allowable_orders().

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
 include/linux/huge_mm.h | 19 +++++++++++++++++++
 mm/huge_memory.c        | 13 +------------
 mm/shmem.c              |  7 +------
 3 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 795df660efa5..d77891332b35 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -309,6 +309,25 @@ struct thpsize {
 	(transparent_hugepage_flags &					\
 	 (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
 
+static inline bool thp_vma_disabled(struct vm_area_struct *vma,
+				    unsigned long vm_flags)
+{
+	/*
+	 * Explicitly disabled through madvise or prctl, or some
+	 * architectures may disable THP for some mappings, for
+	 * example, s390 kvm.
+	 */
+	if (vma && ((vm_flags & VM_NOHUGEPAGE) ||
+	     test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags)))
+		return true;
+
+	/* If the hardware/firmware marked hugepage support disabled. */
+	if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_UNSUPPORTED))
+		return true;
+
+	return false;
+}
+
 unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr,
 		unsigned long len, unsigned long pgoff, unsigned long flags);
 unsigned long thp_get_unmapped_area_vmflags(struct file *filp, unsigned long addr,
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index d23e4aab7511..30912a93f7dc 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -123,18 +123,7 @@ unsigned long __thp_vma_allowable_orders(struct vm_area_struct *vma,
 	if (!vma->vm_mm)		/* vdso */
 		return 0;
 
-	/*
-	 * Explicitly disabled through madvise or prctl, or some
-	 * architectures may disable THP for some mappings, for
-	 * example, s390 kvm.
-	 * */
-	if ((vm_flags & VM_NOHUGEPAGE) ||
-	    test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
-		return 0;
-	/*
-	 * If the hardware/firmware marked hugepage support disabled.
-	 */
-	if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_UNSUPPORTED))
+	if (thp_vma_disabled(vma, vm_flags))
 		return 0;
 
 	/* khugepaged doesn't collapse DAX vma, but page fault is fine. */
diff --git a/mm/shmem.c b/mm/shmem.c
index 0a2f78c2b919..34a31e7e527c 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1683,12 +1683,7 @@ unsigned long shmem_allowable_huge_orders(struct inode *inode,
 	loff_t i_size;
 	int order;
 
-	if (vma && ((vm_flags & VM_NOHUGEPAGE) ||
-	    test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags)))
-		return 0;
-
-	/* If the hardware/firmware marked hugepage support disabled. */
-	if (transparent_hugepage_flags & (1 << TRANSPARENT_HUGEPAGE_UNSUPPORTED))
+	if (thp_vma_disabled(vma, vm_flags))
 		return 0;
 
 	global_huge = shmem_huge_global_enabled(inode, index, write_end,
-- 
2.27.0