1 files changed, 104 insertions, 12 deletions

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 4fc590a1257d..899f6a81e77a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1437,7 +1437,76 @@ void dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn)
 		dissolve_free_huge_page(pfn_to_page(pfn));
 }
 
-static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
+/*
+ * There are 3 ways this can get called:
+ * 1. With vma+addr: we use the VMA's memory policy
+ * 2. With !vma, but nid=NUMA_NO_NODE:  We try to allocate a huge
+ *    page from any node, and let the buddy allocator itself figure
+ *    it out.
+ * 3. With !vma, but nid!=NUMA_NO_NODE.  We allocate a huge page
+ *    strictly from 'nid'
+ */
+static struct page *__hugetlb_alloc_buddy_huge_page(struct hstate *h,
+		struct vm_area_struct *vma, unsigned long addr, int nid)
+{
+	int order = huge_page_order(h);
+	gfp_t gfp = htlb_alloc_mask(h)|__GFP_COMP|__GFP_REPEAT|__GFP_NOWARN;
+	unsigned int cpuset_mems_cookie;
+
+	/*
+	 * We need a VMA to get a memory policy.  If we do not
+	 * have one, we use the 'nid' argument
+	 */
+	if (!vma) {
+		/*
+		 * If a specific node is requested, make sure to
+		 * get memory from there, but only when a node
+		 * is explicitly specified.
+		 */
+		if (nid != NUMA_NO_NODE)
+			gfp |= __GFP_THISNODE;
+		/*
+		 * Make sure to call something that can handle
+		 * nid=NUMA_NO_NODE
+		 */
+		return alloc_pages_node(nid, gfp, order);
+	}
+
+	/*
+	 * OK, so we have a VMA.  Fetch the mempolicy and try to
+	 * allocate a huge page with it.
+	 */
+	do {
+		struct page *page;
+		struct mempolicy *mpol;
+		struct zonelist *zl;
+		nodemask_t *nodemask;
+
+		cpuset_mems_cookie = read_mems_allowed_begin();
+		zl = huge_zonelist(vma, addr, gfp, &mpol, &nodemask);
+		mpol_cond_put(mpol);
+		page = __alloc_pages_nodemask(gfp, order, zl, nodemask);
+		if (page)
+			return page;
+	} while (read_mems_allowed_retry(cpuset_mems_cookie));
+
+	return NULL;
+}
+
+/*
+ * There are two ways to allocate a huge page:
+ * 1. When you have a VMA and an address (like a fault)
+ * 2. When you have no VMA (like when setting /proc/.../nr_hugepages)
+ *
+ * 'vma' and 'addr' are only for (1).  'nid' is always NUMA_NO_NODE in
+ * this case which signifies that the allocation should be done with
+ * respect for the VMA's memory policy.
+ *
+ * For (2), we ignore 'vma' and 'addr' and use 'nid' exclusively. This
+ * implies that memory policies will not be taken in to account.
+ */
+static struct page *__alloc_buddy_huge_page(struct hstate *h,
+		struct vm_area_struct *vma, unsigned long addr, int nid)
 {
 	struct page *page;
 	unsigned int r_nid;
@@ -1446,6 +1515,15 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
 		return NULL;
 
 	/*
+	 * Make sure that anyone specifying 'nid' is not also specifying a VMA.
+	 * This makes sure the caller is picking _one_ of the modes with which
+	 * we can call this function, not both.
+	 */
+	if (vma || (addr != -1)) {
+		WARN_ON_ONCE(addr == -1);
+		WARN_ON_ONCE(nid != NUMA_NO_NODE);
+	}
+	/*
 	 * Assume we will successfully allocate the surplus page to
 	 * prevent racing processes from causing the surplus to exceed
 	 * overcommit
@@ -1478,14 +1556,7 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
 	}
 	spin_unlock(&hugetlb_lock);
 
-	if (nid == NUMA_NO_NODE)
-		page = alloc_pages(htlb_alloc_mask(h)|__GFP_COMP|
-				   __GFP_REPEAT|__GFP_NOWARN,
-				   huge_page_order(h));
-	else
-		page = __alloc_pages_node(nid,
-			htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE|
-			__GFP_REPEAT|__GFP_NOWARN, huge_page_order(h));
+	page = __hugetlb_alloc_buddy_huge_page(h, vma, addr, nid);
 
 	spin_lock(&hugetlb_lock);
 	if (page) {
@@ -1510,6 +1581,27 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
 }
 
 /*
+ * Allocate a huge page from 'nid'.  Note, 'nid' may be
+ * NUMA_NO_NODE, which means that it may be allocated
+ * anywhere.
+ */
+struct page *__alloc_buddy_huge_page_no_mpol(struct hstate *h, int nid)
+{
+	unsigned long addr = -1;
+
+	return __alloc_buddy_huge_page(h, NULL, addr, nid);
+}
+
+/*
+ * Use the VMA's mpolicy to allocate a huge page from the buddy.
+ */
+struct page *__alloc_buddy_huge_page_with_mpol(struct hstate *h,
+		struct vm_area_struct *vma, unsigned long addr)
+{
+	return __alloc_buddy_huge_page(h, vma, addr, NUMA_NO_NODE);
+}
+
+/*
  * This allocation function is useful in the context where vma is irrelevant.
  * E.g. soft-offlining uses this function because it only cares physical
  * address of error page.
@@ -1524,7 +1616,7 @@ struct page *alloc_huge_page_node(struct hstate *h, int nid)
 	spin_unlock(&hugetlb_lock);
 
 	if (!page)
-		page = alloc_buddy_huge_page(h, nid);
+		page = __alloc_buddy_huge_page_no_mpol(h, nid);
 
 	return page;
 }
@@ -1554,7 +1646,7 @@ static int gather_surplus_pages(struct hstate *h, int delta)
 retry:
 	spin_unlock(&hugetlb_lock);
 	for (i = 0; i < needed; i++) {
-		page = alloc_buddy_huge_page(h, NUMA_NO_NODE);
+		page = __alloc_buddy_huge_page_no_mpol(h, NUMA_NO_NODE);
 		if (!page) {
 			alloc_ok = false;
 			break;
@@ -1787,7 +1879,7 @@ struct page *alloc_huge_page(struct vm_area_struct *vma,
 	page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, gbl_chg);
 	if (!page) {
 		spin_unlock(&hugetlb_lock);
-		page = alloc_buddy_huge_page(h, NUMA_NO_NODE);
+		page = __alloc_buddy_huge_page_with_mpol(h, vma, addr);
 		if (!page)
 			goto out_uncharge_cgroup;