2 files changed, 26 insertions, 64 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 1b8ca160f1d0..1d803c2d0184 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1998,45 +1998,26 @@ int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end)
  */
 void swapin_readahead(swp_entry_t entry, unsigned long addr,struct vm_area_struct *vma)
 {
-#ifdef CONFIG_NUMA
-	struct vm_area_struct *next_vma = vma ? vma->vm_next : NULL;
-#endif
-	int i, num;
-	struct page *new_page;
+	int nr_pages;
+	struct page *page;
 	unsigned long offset;
+	unsigned long end_offset;
 
 	/*
-	 * Get the number of handles we should do readahead io to.
+	 * Get starting offset for readaround, and number of pages to read.
+	 * Adjust starting address by readbehind (for NUMA interleave case)?
+	 * No, it's very unlikely that swap layout would follow vma layout,
+	 * more likely that neighbouring swap pages came from the same node:
+	 * so use the same "addr" to choose the same node for each swap read.
 	 */
-	num = valid_swaphandles(entry, &offset);
-	for (i = 0; i < num; offset++, i++) {
+	nr_pages = valid_swaphandles(entry, &offset);
+	for (end_offset = offset + nr_pages; offset < end_offset; offset++) {
 		/* Ok, do the async read-ahead now */
-		new_page = read_swap_cache_async(swp_entry(swp_type(entry),
-							   offset), vma, addr);
-		if (!new_page)
+		page = read_swap_cache_async(swp_entry(swp_type(entry), offset),
+						vma, addr);
+		if (!page)
 			break;
-		page_cache_release(new_page);
-#ifdef CONFIG_NUMA
-		/*
-		 * Find the next applicable VMA for the NUMA policy.
-		 */
-		addr += PAGE_SIZE;
-		if (addr == 0)
-			vma = NULL;
-		if (vma) {
-			if (addr >= vma->vm_end) {
-				vma = next_vma;
-				next_vma = vma ? vma->vm_next : NULL;
-			}
-			if (vma && addr < vma->vm_start)
-				vma = NULL;
-		} else {
-			if (next_vma && addr >= next_vma->vm_start) {
-				vma = next_vma;
-				next_vma = vma->vm_next;
-			}
-		}
-#endif
+		page_cache_release(page);
 	}
 	lru_add_drain();	/* Push any new pages onto the LRU now */
 }
diff --git a/mm/shmem.c b/mm/shmem.c
index 51b3d6ccddab..88c6685f16b7 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1025,53 +1025,34 @@ out:
 	return err;
 }
 
-static struct page *shmem_swapin_async(struct shared_policy *p,
+static struct page *shmem_swapin(struct shmem_inode_info *info,
 				       swp_entry_t entry, unsigned long idx)
 {
-	struct page *page;
 	struct vm_area_struct pvma;
+	struct page *page;
 
 	/* Create a pseudo vma that just contains the policy */
-	memset(&pvma, 0, sizeof(struct vm_area_struct));
-	pvma.vm_end = PAGE_SIZE;
+	pvma.vm_start = 0;
 	pvma.vm_pgoff = idx;
-	pvma.vm_policy = mpol_shared_policy_lookup(p, idx);
+	pvma.vm_ops = NULL;
+	pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, idx);
+	swapin_readahead(entry, 0, &pvma);
 	page = read_swap_cache_async(entry, &pvma, 0);
 	mpol_free(pvma.vm_policy);
 	return page;
 }
 
-static struct page *shmem_swapin(struct shmem_inode_info *info,
-				 swp_entry_t entry, unsigned long idx)
-{
-	struct shared_policy *p = &info->policy;
-	int i, num;
-	struct page *page;
-	unsigned long offset;
-
-	num = valid_swaphandles(entry, &offset);
-	for (i = 0; i < num; offset++, i++) {
-		page = shmem_swapin_async(p,
-				swp_entry(swp_type(entry), offset), idx);
-		if (!page)
-			break;
-		page_cache_release(page);
-	}
-	lru_add_drain();	/* Push any new pages onto the LRU now */
-	return shmem_swapin_async(p, entry, idx);
-}
-
-static struct page *
-shmem_alloc_page(gfp_t gfp, struct shmem_inode_info *info,
-		 unsigned long idx)
+static struct page *shmem_alloc_page(gfp_t gfp, struct shmem_inode_info *info,
+					unsigned long idx)
 {
 	struct vm_area_struct pvma;
 	struct page *page;
 
-	memset(&pvma, 0, sizeof(struct vm_area_struct));
-	pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, idx);
+	/* Create a pseudo vma that just contains the policy */
+	pvma.vm_start = 0;
 	pvma.vm_pgoff = idx;
-	pvma.vm_end = PAGE_SIZE;
+	pvma.vm_ops = NULL;
+	pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, idx);
 	page = alloc_page_vma(gfp, &pvma, 0);
 	mpol_free(pvma.vm_policy);
 	return page;