[PATCH v3 3/8] mm/hugetlb: unify migration callbacks

[js1304@gmail.com]

From: Joonsoo Kim <iamjoonsoo.kim@lge.com>

There is no difference between two migration callback functions,
alloc_huge_page_node() and alloc_huge_page_nodemask(), except
__GFP_THISNODE handling. This patch adds an argument, gfp_mask, on
alloc_huge_page_nodemask() and replace the callsite for
alloc_huge_page_node() with the call to
alloc_huge_page_nodemask(..., __GFP_THISNODE).

It's safe to remove a node id check in alloc_huge_page_node() since
there is no caller passing NUMA_NO_NODE as a node id.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
---
 include/linux/hugetlb.h | 11 +++--------
 mm/hugetlb.c            | 26 +++-----------------------
 mm/mempolicy.c          |  9 +++++----
 mm/migrate.c            |  5 +++--
 4 files changed, 14 insertions(+), 37 deletions(-)

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 50650d0..8a8b755 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -504,9 +504,8 @@ struct huge_bootmem_page {
 
 struct page *alloc_huge_page(struct vm_area_struct *vma,
 				unsigned long addr, int avoid_reserve);
-struct page *alloc_huge_page_node(struct hstate *h, int nid);
 struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
-				nodemask_t *nmask);
+				nodemask_t *nmask, gfp_t gfp_mask);
 struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma,
 				unsigned long address);
 struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask,
@@ -759,13 +758,9 @@ static inline struct page *alloc_huge_page(struct vm_area_struct *vma,
 	return NULL;
 }
 
-static inline struct page *alloc_huge_page_node(struct hstate *h, int nid)
-{
-	return NULL;
-}
-
 static inline struct page *
-alloc_huge_page_nodemask(struct hstate *h, int preferred_nid, nodemask_t *nmask)
+alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
+			nodemask_t *nmask, gfp_t gfp_mask)
 {
 	return NULL;
 }
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index d54bb7e..bd408f2 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1979,30 +1979,10 @@ struct page *alloc_buddy_huge_page_with_mpol(struct hstate *h,
 }
 
 /* page migration callback function */
-struct page *alloc_huge_page_node(struct hstate *h, int nid)
-{
-	gfp_t gfp_mask = htlb_alloc_mask(h);
-	struct page *page = NULL;
-
-	if (nid != NUMA_NO_NODE)
-		gfp_mask |= __GFP_THISNODE;
-
-	spin_lock(&hugetlb_lock);
-	if (h->free_huge_pages - h->resv_huge_pages > 0)
-		page = dequeue_huge_page_nodemask(h, gfp_mask, nid, NULL);
-	spin_unlock(&hugetlb_lock);
-
-	if (!page)
-		page = alloc_migrate_huge_page(h, gfp_mask, nid, NULL);
-
-	return page;
-}
-
-/* page migration callback function */
 struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
-		nodemask_t *nmask)
+		nodemask_t *nmask, gfp_t gfp_mask)
 {
-	gfp_t gfp_mask = htlb_alloc_mask(h);
+	gfp_mask |= htlb_alloc_mask(h);
 
 	spin_lock(&hugetlb_lock);
 	if (h->free_huge_pages - h->resv_huge_pages > 0) {
@@ -2031,7 +2011,7 @@ struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma,
 
 	gfp_mask = htlb_alloc_mask(h);
 	node = huge_node(vma, address, gfp_mask, &mpol, &nodemask);
-	page = alloc_huge_page_nodemask(h, node, nodemask);
+	page = alloc_huge_page_nodemask(h, node, nodemask, 0);
 	mpol_cond_put(mpol);
 
 	return page;
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index b9e85d4..f21cff5 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1068,10 +1068,11 @@ static int migrate_page_add(struct page *page, struct list_head *pagelist,
 /* page allocation callback for NUMA node migration */
 struct page *alloc_new_node_page(struct page *page, unsigned long node)
 {
-	if (PageHuge(page))
-		return alloc_huge_page_node(page_hstate(compound_head(page)),
-					node);
-	else if (PageTransHuge(page)) {
+	if (PageHuge(page)) {
+		return alloc_huge_page_nodemask(
+			page_hstate(compound_head(page)), node,
+			NULL, __GFP_THISNODE);
+	} else if (PageTransHuge(page)) {
 		struct page *thp;
 
 		thp = alloc_pages_node(node,
diff --git a/mm/migrate.c b/mm/migrate.c
index 6b5c75b..6ca9f0c 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1543,10 +1543,11 @@ struct page *new_page_nodemask(struct page *page,
 	unsigned int order = 0;
 	struct page *new_page = NULL;
 
-	if (PageHuge(page))
+	if (PageHuge(page)) {
 		return alloc_huge_page_nodemask(
 				page_hstate(compound_head(page)),
-				preferred_nid, nodemask);
+				preferred_nid, nodemask, 0);
+	}
 
 	if (PageTransHuge(page)) {
 		gfp_mask |= GFP_TRANSHUGE;
-- 
2.7.4