1 files changed, 14 insertions, 33 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 */
 }