[PATCH v1 5/5] mm: Add update_mmu_tlb_range()

[Bang Li]

After the commit 19eaf44954df ("mm: thp: support allocation of anonymous
multi-size THP"), it may need to batch update tlb of an address range
through the update_mmu_tlb function. We can simplify this operation by
adding the update_mmu_tlb_range function, which may also reduce the
execution of some unnecessary code in some architectures.

Signed-off-by: Bang Li <libang.li@xxxxxxxxxxxx>
---
 include/linux/pgtable.h | 5 +++++
 mm/memory.c             | 4 +---
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 18019f037bae..73411dfebf7a 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -734,6 +734,11 @@ static inline void update_mmu_tlb(struct vm_area_struct *vma,
 				unsigned long address, pte_t *ptep)
 {
 }
+
+static inline void update_mmu_tlb_range(struct vm_area_struct *vma,
+				unsigned long address, pte_t *ptep, unsigned int nr)
+{
+}
 #define __HAVE_ARCH_UPDATE_MMU_TLB
 #endif
 
diff --git a/mm/memory.c b/mm/memory.c
index 6647685fd3c4..1f0ca362b82a 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4396,7 +4396,6 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
 	vm_fault_t ret = 0;
 	int nr_pages = 1;
 	pte_t entry;
-	int i;
 
 	/* File mapping without ->vm_ops ? */
 	if (vma->vm_flags & VM_SHARED)
@@ -4465,8 +4464,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
 		update_mmu_tlb(vma, addr, vmf->pte);
 		goto release;
 	} else if (nr_pages > 1 && !pte_range_none(vmf->pte, nr_pages)) {
-		for (i = 0; i < nr_pages; i++)
-			update_mmu_tlb(vma, addr + PAGE_SIZE * i, vmf->pte + i);
+		update_mmu_tlb_range(vma, addr, vmf->pte, nr_pages);
 		goto release;
 	}
 
-- 
2.19.1.6.gb485710b