mm: rotate_reclaimable_page() cleanup

Clean up messy conditional calling of test_clear_page_writeback() from both
rotate_reclaimable_page() and end_page_writeback().

The only user of rotate_reclaimable_page() is end_page_writeback() so this is
OK.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 18 insertions, 29 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index 07e9d9258b48..239d36163bbe 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -576,10 +576,12 @@ EXPORT_SYMBOL(unlock_page);
  */
 void end_page_writeback(struct page *page)
 {
-        if (!TestClearPageReclaim(page) || rotate_reclaimable_page(page)) {
-                if (!test_clear_page_writeback(page))
-                        BUG();
-        }
+        if (TestClearPageReclaim(page))
+                rotate_reclaimable_page(page);
+
+        if (!test_clear_page_writeback(page))
+                BUG();
+
         smp_mb__after_clear_bit();
         wake_up_page(page, PG_writeback);
 }
diff --git a/mm/swap.c b/mm/swap.c
index aa1139ccf3a7..91e194445a5e 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -132,34 +132,21 @@ static void pagevec_move_tail(struct pagevec *pvec)
  * Writeback is about to end against a page which has been marked for immediate
  * reclaim.  If it still appears to be reclaimable, move it to the tail of the
  * inactive list.
- *
- * Returns zero if it cleared PG_writeback.
  */
-int rotate_reclaimable_page(struct page *page)
+void  rotate_reclaimable_page(struct page *page)
 {
-        struct pagevec *pvec;
-        unsigned long flags;
-
-        if (PageLocked(page))
-                return 1;
-        if (PageDirty(page))
-                return 1;
-        if (PageActive(page))
-                return 1;
-        if (!PageLRU(page))
-                return 1;
-
-        page_cache_get(page);
-        local_irq_save(flags);
-        pvec = &__get_cpu_var(lru_rotate_pvecs);
-        if (!pagevec_add(pvec, page))
-                pagevec_move_tail(pvec);
-        local_irq_restore(flags);
-
-        if (!test_clear_page_writeback(page))
-                BUG();
+        if (!PageLocked(page) && !PageDirty(page) && !PageActive(page) &&
+            PageLRU(page)) {
+                struct pagevec *pvec;
+                unsigned long flags;
 
-        return 0;
+                page_cache_get(page);
+                local_irq_save(flags);
+                pvec = &__get_cpu_var(lru_rotate_pvecs);
+                if (!pagevec_add(pvec, page))
+                        pagevec_move_tail(pvec);
+                local_irq_restore(flags);
+        }
 }
 
 /*