1 files changed, 17 insertions, 36 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index 084ad0fe73c7..7c00f105845e 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1255,7 +1255,6 @@ unsigned find_get_entries(struct address_space *mapping,
                 return 0;
 
         rcu_read_lock();
-restart:
         radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) {
                 struct page *page;
 repeat:
@@ -1263,8 +1262,10 @@ repeat:
                 if (unlikely(!page))
                         continue;
                 if (radix_tree_exception(page)) {
-                        if (radix_tree_deref_retry(page))
-                                goto restart;
+                        if (radix_tree_deref_retry(page)) {
+                                slot = radix_tree_iter_retry(&iter);
+                                continue;
+                        }
                         /*
                          * A shadow entry of a recently evicted page, a swap
                          * entry from shmem/tmpfs or a DAX entry.  Return it
@@ -1317,7 +1318,6 @@ unsigned find_get_pages(struct address_space *mapping, pgoff_t start,
                 return 0;
 
         rcu_read_lock();
-restart:
         radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) {
                 struct page *page;
 repeat:
@@ -1327,13 +1327,8 @@ repeat:
 
                 if (radix_tree_exception(page)) {
                         if (radix_tree_deref_retry(page)) {
-                                /*
-                                 * Transient condition which can only trigger
-                                 * when entry at index 0 moves out of or back
-                                 * to root: none yet gotten, safe to restart.
-                                 */
-                                WARN_ON(iter.index);
-                                goto restart;
+                                slot = radix_tree_iter_retry(&iter);
+                                continue;
                         }
                         /*
                          * A shadow entry of a recently evicted page,
@@ -1384,7 +1379,6 @@ unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index,
                 return 0;
 
         rcu_read_lock();
-restart:
         radix_tree_for_each_contig(slot, &mapping->page_tree, &iter, index) {
                 struct page *page;
 repeat:
@@ -1395,12 +1389,8 @@ repeat:
 
                 if (radix_tree_exception(page)) {
                         if (radix_tree_deref_retry(page)) {
-                                /*
-                                 * Transient condition which can only trigger
-                                 * when entry at index 0 moves out of or back
-                                 * to root: none yet gotten, safe to restart.
-                                 */
-                                goto restart;
+                                slot = radix_tree_iter_retry(&iter);
+                                continue;
                         }
                         /*
                          * A shadow entry of a recently evicted page,
@@ -1460,7 +1450,6 @@ unsigned find_get_pages_tag(struct address_space *mapping, pgoff_t *index,
                 return 0;
 
         rcu_read_lock();
-restart:
         radix_tree_for_each_tagged(slot, &mapping->page_tree,
                                    &iter, *index, tag) {
                 struct page *page;
@@ -1471,12 +1460,8 @@ repeat:
 
                 if (radix_tree_exception(page)) {
                         if (radix_tree_deref_retry(page)) {
-                                /*
-                                 * Transient condition which can only trigger
-                                 * when entry at index 0 moves out of or back
-                                 * to root: none yet gotten, safe to restart.
-                                 */
-                                goto restart;
+                                slot = radix_tree_iter_retry(&iter);
+                                continue;
                         }
                         /*
                          * A shadow entry of a recently evicted page.
@@ -1539,7 +1524,6 @@ unsigned find_get_entries_tag(struct address_space *mapping, pgoff_t start,
                 return 0;
 
         rcu_read_lock();
-restart:
         radix_tree_for_each_tagged(slot, &mapping->page_tree,
                                    &iter, start, tag) {
                 struct page *page;
@@ -1549,12 +1533,8 @@ repeat:
                         continue;
                 if (radix_tree_exception(page)) {
                         if (radix_tree_deref_retry(page)) {
-                                /*
-                                 * Transient condition which can only trigger
-                                 * when entry at index 0 moves out of or back
-                                 * to root: none yet gotten, safe to restart.
-                                 */
-                                goto restart;
+                                slot = radix_tree_iter_retry(&iter);
+                                continue;
                         }
 
                         /*
@@ -2171,10 +2151,11 @@ repeat:
                 if (unlikely(!page))
                         goto next;
                 if (radix_tree_exception(page)) {
-                        if (radix_tree_deref_retry(page))
-                                break;
-                        else
-                                goto next;
+                        if (radix_tree_deref_retry(page)) {
+                                slot = radix_tree_iter_retry(&iter);
+                                continue;
+                        }
+                        goto next;
                 }
 
                 if (!page_cache_get_speculative(page))