1 files changed, 132 insertions, 154 deletions

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 0e0961b8c39c..4721046a134a 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -471,24 +471,34 @@ static const struct mempolicy_operations mpol_ops[MPOL_MAX] = {
 static void migrate_page_add(struct page *page, struct list_head *pagelist,
 				unsigned long flags);
 
+struct queue_pages {
+	struct list_head *pagelist;
+	unsigned long flags;
+	nodemask_t *nmask;
+	struct vm_area_struct *prev;
+};
+
 /*
  * Scan through pages checking if pages follow certain conditions,
  * and move them to the pagelist if they do.
  */
-static int queue_pages_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
-		unsigned long addr, unsigned long end,
-		const nodemask_t *nodes, unsigned long flags,
-		void *private)
+static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr,
+			unsigned long end, struct mm_walk *walk)
 {
-	pte_t *orig_pte;
+	struct vm_area_struct *vma = walk->vma;
+	struct page *page;
+	struct queue_pages *qp = walk->private;
+	unsigned long flags = qp->flags;
+	int nid;
 	pte_t *pte;
 	spinlock_t *ptl;
 
-	orig_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
-	do {
-		struct page *page;
-		int nid;
+	split_huge_page_pmd(vma, addr, pmd);
+	if (pmd_trans_unstable(pmd))
+		return 0;
 
+	pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
+	for (; addr != end; pte++, addr += PAGE_SIZE) {
 		if (!pte_present(*pte))
 			continue;
 		page = vm_normal_page(vma, addr, *pte);
@@ -501,114 +511,46 @@ static int queue_pages_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
 		if (PageReserved(page))
 			continue;
 		nid = page_to_nid(page);
-		if (node_isset(nid, *nodes) == !!(flags & MPOL_MF_INVERT))
+		if (node_isset(nid, *qp->nmask) == !!(flags & MPOL_MF_INVERT))
 			continue;
 
 		if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
-			migrate_page_add(page, private, flags);
-		else
-			break;
-	} while (pte++, addr += PAGE_SIZE, addr != end);
-	pte_unmap_unlock(orig_pte, ptl);
-	return addr != end;
+			migrate_page_add(page, qp->pagelist, flags);
+	}
+	pte_unmap_unlock(pte - 1, ptl);
+	cond_resched();
+	return 0;
 }
 
-static void queue_pages_hugetlb_pmd_range(struct vm_area_struct *vma,
-		pmd_t *pmd, const nodemask_t *nodes, unsigned long flags,
-				    void *private)
+static int queue_pages_hugetlb(pte_t *pte, unsigned long hmask,
+			       unsigned long addr, unsigned long end,
+			       struct mm_walk *walk)
 {
 #ifdef CONFIG_HUGETLB_PAGE
+	struct queue_pages *qp = walk->private;
+	unsigned long flags = qp->flags;
 	int nid;
 	struct page *page;
 	spinlock_t *ptl;
 	pte_t entry;
 
-	ptl = huge_pte_lock(hstate_vma(vma), vma->vm_mm, (pte_t *)pmd);
-	entry = huge_ptep_get((pte_t *)pmd);
+	ptl = huge_pte_lock(hstate_vma(walk->vma), walk->mm, pte);
+	entry = huge_ptep_get(pte);
 	if (!pte_present(entry))
 		goto unlock;
 	page = pte_page(entry);
 	nid = page_to_nid(page);
-	if (node_isset(nid, *nodes) == !!(flags & MPOL_MF_INVERT))
+	if (node_isset(nid, *qp->nmask) == !!(flags & MPOL_MF_INVERT))
 		goto unlock;
 	/* With MPOL_MF_MOVE, we migrate only unshared hugepage. */
 	if (flags & (MPOL_MF_MOVE_ALL) ||
 	    (flags & MPOL_MF_MOVE && page_mapcount(page) == 1))
-		isolate_huge_page(page, private);
+		isolate_huge_page(page, qp->pagelist);
 unlock:
 	spin_unlock(ptl);
 #else
 	BUG();
 #endif
-}
-
-static inline int queue_pages_pmd_range(struct vm_area_struct *vma, pud_t *pud,
-		unsigned long addr, unsigned long end,
-		const nodemask_t *nodes, unsigned long flags,
-		void *private)
-{
-	pmd_t *pmd;
-	unsigned long next;
-
-	pmd = pmd_offset(pud, addr);
-	do {
-		next = pmd_addr_end(addr, end);
-		if (!pmd_present(*pmd))
-			continue;
-		if (pmd_huge(*pmd) && is_vm_hugetlb_page(vma)) {
-			queue_pages_hugetlb_pmd_range(vma, pmd, nodes,
-						flags, private);
-			continue;
-		}
-		split_huge_page_pmd(vma, addr, pmd);
-		if (pmd_none_or_trans_huge_or_clear_bad(pmd))
-			continue;
-		if (queue_pages_pte_range(vma, pmd, addr, next, nodes,
-				    flags, private))
-			return -EIO;
-	} while (pmd++, addr = next, addr != end);
-	return 0;
-}
-
-static inline int queue_pages_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
-		unsigned long addr, unsigned long end,
-		const nodemask_t *nodes, unsigned long flags,
-		void *private)
-{
-	pud_t *pud;
-	unsigned long next;
-
-	pud = pud_offset(pgd, addr);
-	do {
-		next = pud_addr_end(addr, end);
-		if (pud_huge(*pud) && is_vm_hugetlb_page(vma))
-			continue;
-		if (pud_none_or_clear_bad(pud))
-			continue;
-		if (queue_pages_pmd_range(vma, pud, addr, next, nodes,
-				    flags, private))
-			return -EIO;
-	} while (pud++, addr = next, addr != end);
-	return 0;
-}
-
-static inline int queue_pages_pgd_range(struct vm_area_struct *vma,
-		unsigned long addr, unsigned long end,
-		const nodemask_t *nodes, unsigned long flags,
-		void *private)
-{
-	pgd_t *pgd;
-	unsigned long next;
-
-	pgd = pgd_offset(vma->vm_mm, addr);
-	do {
-		next = pgd_addr_end(addr, end);
-		if (pgd_none_or_clear_bad(pgd))
-			continue;
-		if (queue_pages_pud_range(vma, pgd, addr, next, nodes,
-				    flags, private))
-			return -EIO;
-	} while (pgd++, addr = next, addr != end);
 	return 0;
 }
 
@@ -627,7 +569,7 @@ unsigned long change_prot_numa(struct vm_area_struct *vma,
 {
 	int nr_updated;
 
-	nr_updated = change_protection(vma, addr, end, vma->vm_page_prot, 0, 1);
+	nr_updated = change_protection(vma, addr, end, PAGE_NONE, 0, 1);
 	if (nr_updated)
 		count_vm_numa_events(NUMA_PTE_UPDATES, nr_updated);
 
@@ -641,6 +583,49 @@ static unsigned long change_prot_numa(struct vm_area_struct *vma,
 }
 #endif /* CONFIG_NUMA_BALANCING */
 
+static int queue_pages_test_walk(unsigned long start, unsigned long end,
+				struct mm_walk *walk)
+{
+	struct vm_area_struct *vma = walk->vma;
+	struct queue_pages *qp = walk->private;
+	unsigned long endvma = vma->vm_end;
+	unsigned long flags = qp->flags;
+
+	if (vma->vm_flags & VM_PFNMAP)
+		return 1;
+
+	if (endvma > end)
+		endvma = end;
+	if (vma->vm_start > start)
+		start = vma->vm_start;
+
+	if (!(flags & MPOL_MF_DISCONTIG_OK)) {
+		if (!vma->vm_next && vma->vm_end < end)
+			return -EFAULT;
+		if (qp->prev && qp->prev->vm_end < vma->vm_start)
+			return -EFAULT;
+	}
+
+	qp->prev = vma;
+
+	if (vma->vm_flags & VM_PFNMAP)
+		return 1;
+
+	if (flags & MPOL_MF_LAZY) {
+		/* Similar to task_numa_work, skip inaccessible VMAs */
+		if (vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE))
+			change_prot_numa(vma, start, endvma);
+		return 1;
+	}
+
+	if ((flags & MPOL_MF_STRICT) ||
+	    ((flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) &&
+	     vma_migratable(vma)))
+		/* queue pages from current vma */
+		return 0;
+	return 1;
+}
+
 /*
  * Walk through page tables and collect pages to be migrated.
  *
@@ -650,50 +635,24 @@ static unsigned long change_prot_numa(struct vm_area_struct *vma,
  */
 static int
 queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end,
-		const nodemask_t *nodes, unsigned long flags, void *private)
-{
-	int err = 0;
-	struct vm_area_struct *vma, *prev;
-
-	vma = find_vma(mm, start);
-	if (!vma)
-		return -EFAULT;
-	prev = NULL;
-	for (; vma && vma->vm_start < end; vma = vma->vm_next) {
-		unsigned long endvma = vma->vm_end;
-
-		if (endvma > end)
-			endvma = end;
-		if (vma->vm_start > start)
-			start = vma->vm_start;
-
-		if (!(flags & MPOL_MF_DISCONTIG_OK)) {
-			if (!vma->vm_next && vma->vm_end < end)
-				return -EFAULT;
-			if (prev && prev->vm_end < vma->vm_start)
-				return -EFAULT;
-		}
-
-		if (flags & MPOL_MF_LAZY) {
-			/* Similar to task_numa_work, skip inaccessible VMAs */
-			if (vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE))
-				change_prot_numa(vma, start, endvma);
-			goto next;
-		}
-
-		if ((flags & MPOL_MF_STRICT) ||
-		     ((flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) &&
-		      vma_migratable(vma))) {
-
-			err = queue_pages_pgd_range(vma, start, endvma, nodes,
-						flags, private);
-			if (err)
-				break;
-		}
-next:
-		prev = vma;
-	}
-	return err;
+		nodemask_t *nodes, unsigned long flags,
+		struct list_head *pagelist)
+{
+	struct queue_pages qp = {
+		.pagelist = pagelist,
+		.flags = flags,
+		.nmask = nodes,
+		.prev = NULL,
+	};
+	struct mm_walk queue_pages_walk = {
+		.hugetlb_entry = queue_pages_hugetlb,
+		.pmd_entry = queue_pages_pte_range,
+		.test_walk = queue_pages_test_walk,
+		.mm = mm,
+		.private = &qp,
+	};
+
+	return walk_page_range(start, end, &queue_pages_walk);
 }
 
 /*
@@ -1988,43 +1947,63 @@ static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
  *	@order:Order of the GFP allocation.
  * 	@vma:  Pointer to VMA or NULL if not available.
  *	@addr: Virtual Address of the allocation. Must be inside the VMA.
+ *	@node: Which node to prefer for allocation (modulo policy).
+ *	@hugepage: for hugepages try only the preferred node if possible
  *
  * 	This function allocates a page from the kernel page pool and applies
  *	a NUMA policy associated with the VMA or the current process.
  *	When VMA is not NULL caller must hold down_read on the mmap_sem of the
  *	mm_struct of the VMA to prevent it from going away. Should be used for
- *	all allocations for pages that will be mapped into
- * 	user space. Returns NULL when no page can be allocated.
- *
- *	Should be called with the mm_sem of the vma hold.
+ *	all allocations for pages that will be mapped into user space. Returns
+ *	NULL when no page can be allocated.
  */
 struct page *
 alloc_pages_vma(gfp_t gfp, int order, struct vm_area_struct *vma,
-		unsigned long addr, int node)
+		unsigned long addr, int node, bool hugepage)
 {
 	struct mempolicy *pol;
 	struct page *page;
 	unsigned int cpuset_mems_cookie;
+	struct zonelist *zl;
+	nodemask_t *nmask;
 
 retry_cpuset:
 	pol = get_vma_policy(vma, addr);
 	cpuset_mems_cookie = read_mems_allowed_begin();
 
-	if (unlikely(pol->mode == MPOL_INTERLEAVE)) {
+	if (unlikely(IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && hugepage &&
+					pol->mode != MPOL_INTERLEAVE)) {
+		/*
+		 * For hugepage allocation and non-interleave policy which
+		 * allows the current node, we only try to allocate from the
+		 * current node and don't fall back to other nodes, as the
+		 * cost of remote accesses would likely offset THP benefits.
+		 *
+		 * If the policy is interleave, or does not allow the current
+		 * node in its nodemask, we allocate the standard way.
+		 */
+		nmask = policy_nodemask(gfp, pol);
+		if (!nmask || node_isset(node, *nmask)) {
+			mpol_cond_put(pol);
+			page = alloc_pages_exact_node(node, gfp, order);
+			goto out;
+		}
+	}
+
+	if (pol->mode == MPOL_INTERLEAVE) {
 		unsigned nid;
 
 		nid = interleave_nid(pol, vma, addr, PAGE_SHIFT + order);
 		mpol_cond_put(pol);
 		page = alloc_page_interleave(gfp, order, nid);
-		if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie)))
-			goto retry_cpuset;
-
-		return page;
+		goto out;
 	}
-	page = __alloc_pages_nodemask(gfp, order,
-				      policy_zonelist(gfp, pol, node),
-				      policy_nodemask(gfp, pol));
+
+	nmask = policy_nodemask(gfp, pol);
+	zl = policy_zonelist(gfp, pol, node);
 	mpol_cond_put(pol);
+	page = __alloc_pages_nodemask(gfp, order, zl, nmask);
+out:
 	if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie)))
 		goto retry_cpuset;
 	return page;
@@ -2838,8 +2817,7 @@ void mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
 			p += snprintf(p, buffer + maxlen - p, "relative");
 	}
 
-	if (!nodes_empty(nodes)) {
-		p += snprintf(p, buffer + maxlen - p, ":");
-	 	p += nodelist_scnprintf(p, buffer + maxlen - p, nodes);
-	}
+	if (!nodes_empty(nodes))
+		p += scnprintf(p, buffer + maxlen - p, ":%*pbl",
+			       nodemask_pr_args(&nodes));
 }