1 files changed, 33 insertions, 144 deletions

diff --git a/mm/migrate.c b/mm/migrate.c
index 9bd6bc12aa72..b7e330900b86 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2048,6 +2048,23 @@ static struct page *alloc_misplaced_dst_page(struct page *page,
 	return newpage;
 }
 
+static struct page *alloc_misplaced_dst_page_thp(struct page *page,
+						 unsigned long data)
+{
+	int nid = (int) data;
+	struct page *newpage;
+
+	newpage = alloc_pages_node(nid, (GFP_TRANSHUGE_LIGHT | __GFP_THISNODE),
+				   HPAGE_PMD_ORDER);
+	if (!newpage)
+		goto out;
+
+	prep_transhuge_page(newpage);
+
+out:
+	return newpage;
+}
+
 static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 {
 	int page_lru;
@@ -2086,12 +2103,6 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 	return 1;
 }
 
-bool pmd_trans_migrating(pmd_t pmd)
-{
-	struct page *page = pmd_page(pmd);
-	return PageLocked(page);
-}
-
 /*
  * Attempt to migrate a misplaced page to the specified destination
  * node. Caller is expected to have an elevated reference count on
@@ -2104,6 +2115,20 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
 	int isolated;
 	int nr_remaining;
 	LIST_HEAD(migratepages);
+	new_page_t *new;
+	bool compound;
+
+	/*
+	 * PTE mapped THP or HugeTLB page can't reach here so the page could
+	 * be either base page or THP.  And it must be head page if it is
+	 * THP.
+	 */
+	compound = PageTransHuge(page);
+
+	if (compound)
+		new = alloc_misplaced_dst_page_thp;
+	else
+		new = alloc_misplaced_dst_page;
 
 	/*
 	 * Don't migrate file pages that are mapped in multiple processes
@@ -2125,9 +2150,8 @@ int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
 		goto out;
 
 	list_add(&page->lru, &migratepages);
-	nr_remaining = migrate_pages(&migratepages, alloc_misplaced_dst_page,
-				     NULL, node, MIGRATE_ASYNC,
-				     MR_NUMA_MISPLACED);
+	nr_remaining = migrate_pages(&migratepages, *new, NULL, node,
+				     MIGRATE_ASYNC, MR_NUMA_MISPLACED);
 	if (nr_remaining) {
 		if (!list_empty(&migratepages)) {
 			list_del(&page->lru);
@@ -2146,141 +2170,6 @@ out:
 	return 0;
 }
 #endif /* CONFIG_NUMA_BALANCING */
-
-#if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
-/*
- * Migrates a THP to a given target node. page must be locked and is unlocked
- * before returning.
- */
-int migrate_misplaced_transhuge_page(struct mm_struct *mm,
-				struct vm_area_struct *vma,
-				pmd_t *pmd, pmd_t entry,
-				unsigned long address,
-				struct page *page, int node)
-{
-	spinlock_t *ptl;
-	pg_data_t *pgdat = NODE_DATA(node);
-	int isolated = 0;
-	struct page *new_page = NULL;
-	int page_lru = page_is_file_lru(page);
-	unsigned long start = address & HPAGE_PMD_MASK;
-
-	new_page = alloc_pages_node(node,
-		(GFP_TRANSHUGE_LIGHT | __GFP_THISNODE),
-		HPAGE_PMD_ORDER);
-	if (!new_page)
-		goto out_fail;
-	prep_transhuge_page(new_page);
-
-	isolated = numamigrate_isolate_page(pgdat, page);
-	if (!isolated) {
-		put_page(new_page);
-		goto out_fail;
-	}
-
-	/* Prepare a page as a migration target */
-	__SetPageLocked(new_page);
-	if (PageSwapBacked(page))
-		__SetPageSwapBacked(new_page);
-
-	/* anon mapping, we can simply copy page->mapping to the new page: */
-	new_page->mapping = page->mapping;
-	new_page->index = page->index;
-	/* flush the cache before copying using the kernel virtual address */
-	flush_cache_range(vma, start, start + HPAGE_PMD_SIZE);
-	migrate_page_copy(new_page, page);
-	WARN_ON(PageLRU(new_page));
-
-	/* Recheck the target PMD */
-	ptl = pmd_lock(mm, pmd);
-	if (unlikely(!pmd_same(*pmd, entry) || !page_ref_freeze(page, 2))) {
-		spin_unlock(ptl);
-
-		/* Reverse changes made by migrate_page_copy() */
-		if (TestClearPageActive(new_page))
-			SetPageActive(page);
-		if (TestClearPageUnevictable(new_page))
-			SetPageUnevictable(page);
-
-		unlock_page(new_page);
-		put_page(new_page);		/* Free it */
-
-		/* Retake the callers reference and putback on LRU */
-		get_page(page);
-		putback_lru_page(page);
-		mod_node_page_state(page_pgdat(page),
-			 NR_ISOLATED_ANON + page_lru, -HPAGE_PMD_NR);
-
-		goto out_unlock;
-	}
-
-	entry = mk_huge_pmd(new_page, vma->vm_page_prot);
-	entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
-
-	/*
-	 * Overwrite the old entry under pagetable lock and establish
-	 * the new PTE. Any parallel GUP will either observe the old
-	 * page blocking on the page lock, block on the page table
-	 * lock or observe the new page. The SetPageUptodate on the
-	 * new page and page_add_new_anon_rmap guarantee the copy is
-	 * visible before the pagetable update.
-	 */
-	page_add_anon_rmap(new_page, vma, start, true);
-	/*
-	 * At this point the pmd is numa/protnone (i.e. non present) and the TLB
-	 * has already been flushed globally.  So no TLB can be currently
-	 * caching this non present pmd mapping.  There's no need to clear the
-	 * pmd before doing set_pmd_at(), nor to flush the TLB after
-	 * set_pmd_at().  Clearing the pmd here would introduce a race
-	 * condition against MADV_DONTNEED, because MADV_DONTNEED only holds the
-	 * mmap_lock for reading.  If the pmd is set to NULL at any given time,
-	 * MADV_DONTNEED won't wait on the pmd lock and it'll skip clearing this
-	 * pmd.
-	 */
-	set_pmd_at(mm, start, pmd, entry);
-	update_mmu_cache_pmd(vma, address, &entry);
-
-	page_ref_unfreeze(page, 2);
-	mlock_migrate_page(new_page, page);
-	page_remove_rmap(page, true);
-	set_page_owner_migrate_reason(new_page, MR_NUMA_MISPLACED);
-
-	spin_unlock(ptl);
-
-	/* Take an "isolate" reference and put new page on the LRU. */
-	get_page(new_page);
-	putback_lru_page(new_page);
-
-	unlock_page(new_page);
-	unlock_page(page);
-	put_page(page);			/* Drop the rmap reference */
-	put_page(page);			/* Drop the LRU isolation reference */
-
-	count_vm_events(PGMIGRATE_SUCCESS, HPAGE_PMD_NR);
-	count_vm_numa_events(NUMA_PAGE_MIGRATE, HPAGE_PMD_NR);
-
-	mod_node_page_state(page_pgdat(page),
-			NR_ISOLATED_ANON + page_lru,
-			-HPAGE_PMD_NR);
-	return isolated;
-
-out_fail:
-	count_vm_events(PGMIGRATE_FAIL, HPAGE_PMD_NR);
-	ptl = pmd_lock(mm, pmd);
-	if (pmd_same(*pmd, entry)) {
-		entry = pmd_modify(entry, vma->vm_page_prot);
-		set_pmd_at(mm, start, pmd, entry);
-		update_mmu_cache_pmd(vma, address, &entry);
-	}
-	spin_unlock(ptl);
-
-out_unlock:
-	unlock_page(page);
-	put_page(page);
-	return 0;
-}
-#endif /* CONFIG_NUMA_BALANCING */
-
 #endif /* CONFIG_NUMA */
 
 #ifdef CONFIG_DEVICE_PRIVATE