mm: huge_memory: use a folio in do_huge_pmd_numa_page()

Use a folio in do_huge_pmd_numa_page(), reduce three page_folio() calls to
one, no functional change intended.

Link: https://lkml.kernel.org/r/20230921074417.24004-3-wangkefeng.wang@huawei.comSigned-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/huge_memory.c

@@ -1517,9 +1517,9 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
 	struct vm_area_struct *vma = vmf->vma;
 	pmd_t oldpmd = vmf->orig_pmd;
 	pmd_t pmd;
-	struct page *page;
+	struct folio *folio;
 	unsigned long haddr = vmf->address & HPAGE_PMD_MASK;
-	int page_nid = NUMA_NO_NODE;
+	int nid = NUMA_NO_NODE;
 	int target_nid, last_cpupid = (-1 & LAST_CPUPID_MASK);
 	bool migrated = false, writable = false;
 	int flags = 0;
@@ -1541,36 +1541,34 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
 	    can_change_pmd_writable(vma, vmf->address, pmd))
 		writable = true;
 
-	page = vm_normal_page_pmd(vma, haddr, pmd);
-	if (!page)
+	folio = vm_normal_folio_pmd(vma, haddr, pmd);
+	if (!folio)
 		goto out_map;
 
 	/* See similar comment in do_numa_page for explanation */
 	if (!writable)
 		flags |= TNF_NO_GROUP;
 
-	page_nid = page_to_nid(page);
+	nid = folio_nid(folio);
 	/*
 	 * For memory tiering mode, cpupid of slow memory page is used
 	 * to record page access time.  So use default value.
 	 */
-	if (node_is_toptier(page_nid))
-		last_cpupid = page_cpupid_last(page);
-	target_nid = numa_migrate_prep(page, vma, haddr, page_nid,
-				       &flags);
-
+	if (node_is_toptier(nid))
+		last_cpupid = page_cpupid_last(&folio->page);
+	target_nid = numa_migrate_prep(&folio->page, vma, haddr, nid, &flags);
 	if (target_nid == NUMA_NO_NODE) {
-		put_page(page);
+		folio_put(folio);
 		goto out_map;
 	}
 
 	spin_unlock(vmf->ptl);
 	writable = false;
 
-	migrated = migrate_misplaced_folio(page_folio(page), vma, target_nid);
+	migrated = migrate_misplaced_folio(folio, vma, target_nid);
 	if (migrated) {
 		flags |= TNF_MIGRATED;
-		page_nid = target_nid;
+		nid = target_nid;
 	} else {
 		flags |= TNF_MIGRATE_FAIL;
 		vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd);
@@ -1582,9 +1580,8 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
 	}
 
 out:
-	if (page_nid != NUMA_NO_NODE)
-		task_numa_fault(last_cpupid, page_nid, HPAGE_PMD_NR,
-				flags);
+	if (nid != NUMA_NO_NODE)
+		task_numa_fault(last_cpupid, nid, HPAGE_PMD_NR, flags);
 
 	return 0;