sched: convert to vma iterator

Use the vma iterator so that the iterator can be invalidated or updated to
avoid each caller doing so.

Link: https://lkml.kernel.org/r/20230120162650.984577-23-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kernel/sched/fair.c

@@ -2938,11 +2938,11 @@ static void task_numa_work(struct callback_head *work)
 	struct task_struct *p = current;
 	struct mm_struct *mm = p->mm;
 	u64 runtime = p->se.sum_exec_runtime;
-	MA_STATE(mas, &mm->mm_mt, 0, 0);
 	struct vm_area_struct *vma;
 	unsigned long start, end;
 	unsigned long nr_pte_updates = 0;
 	long pages, virtpages;
+	struct vma_iterator vmi;
 
 	SCHED_WARN_ON(p != container_of(work, struct task_struct, numa_work));
 
@@ -2995,16 +2995,16 @@ static void task_numa_work(struct callback_head *work)
 
 	if (!mmap_read_trylock(mm))
 		return;
-	mas_set(&mas, start);
-	vma = mas_find(&mas, ULONG_MAX);
+	vma_iter_init(&vmi, mm, start);
+	vma = vma_next(&vmi);
 	if (!vma) {
 		reset_ptenuma_scan(p);
 		start = 0;
-		mas_set(&mas, start);
-		vma = mas_find(&mas, ULONG_MAX);
+		vma_iter_set(&vmi, start);
+		vma = vma_next(&vmi);
 	}
 
-	for (; vma; vma = mas_find(&mas, ULONG_MAX)) {
+	do {
 		if (!vma_migratable(vma) || !vma_policy_mof(vma) ||
 			is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_MIXEDMAP)) {
 			continue;
@@ -3051,7 +3051,7 @@ static void task_numa_work(struct callback_head *work)
 
 			cond_resched();
 		} while (end != vma->vm_end);
-	}
+	} for_each_vma(vmi, vma);
 
 out:
 	/*