Merge branch 'akpm-incoming-1'

* akpm-incoming-1: (176 commits)
  scripts/checkpatch.pl: add check for declaration of pci_device_id
  scripts/checkpatch.pl: add warnings for static char that could be static const char
  checkpatch: version 0.31
  checkpatch: statement/block context analyser should look at sanitised lines
  checkpatch: handle EXPORT_SYMBOL for DEVICE_ATTR and similar
  checkpatch: clean up structure definition macro handline
  checkpatch: update copyright dates
  checkpatch: Add additional attribute #defines
  checkpatch: check for incorrect permissions
  checkpatch: ensure kconfig help checks only apply when we are adding help
  checkpatch: simplify and consolidate "missing space after" checks
  checkpatch: add check for space after struct, union, and enum
  checkpatch: returning errno typically should be negative
  checkpatch: handle casts better fixing false categorisation of : as binary
  checkpatch: ensure we do not collapse bracketed sections into constants
  checkpatch: suggest cleanpatch and cleanfile when appropriate
  checkpatch: types may sit on a line on their own
  checkpatch: fix regressions in "fix handling of leading spaces"
  div64_u64(): improve precision on 32bit platforms
  lib/parser: cleanup match_number()
  ...

1 files changed, 19 insertions, 12 deletions

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index e3bccac1f025..b840afa89761 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -415,14 +415,8 @@ void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty)
 
 	if (vm_dirty_bytes)
 		dirty = DIV_ROUND_UP(vm_dirty_bytes, PAGE_SIZE);
-	else {
-		int dirty_ratio;
-
-		dirty_ratio = vm_dirty_ratio;
-		if (dirty_ratio < 5)
-			dirty_ratio = 5;
-		dirty = (dirty_ratio * available_memory) / 100;
-	}
+	else
+		dirty = (vm_dirty_ratio * available_memory) / 100;
 
 	if (dirty_background_bytes)
 		background = DIV_ROUND_UP(dirty_background_bytes, PAGE_SIZE);
@@ -510,7 +504,7 @@ static void balance_dirty_pages(struct address_space *mapping,
 		 * catch-up. This avoids (excessively) small writeouts
 		 * when the bdi limits are ramping up.
 		 */
-		if (nr_reclaimable + nr_writeback <
+		if (nr_reclaimable + nr_writeback <=
 				(background_thresh + dirty_thresh) / 2)
 			break;
 
@@ -542,8 +536,8 @@ static void balance_dirty_pages(struct address_space *mapping,
 		 * the last resort safeguard.
 		 */
 		dirty_exceeded =
-			(bdi_nr_reclaimable + bdi_nr_writeback >= bdi_thresh)
-			|| (nr_reclaimable + nr_writeback >= dirty_thresh);
+			(bdi_nr_reclaimable + bdi_nr_writeback > bdi_thresh)
+			|| (nr_reclaimable + nr_writeback > dirty_thresh);
 
 		if (!dirty_exceeded)
 			break;
@@ -1121,6 +1115,7 @@ void account_page_dirtied(struct page *page, struct address_space *mapping)
 {
 	if (mapping_cap_account_dirty(mapping)) {
 		__inc_zone_page_state(page, NR_FILE_DIRTY);
+		__inc_zone_page_state(page, NR_DIRTIED);
 		__inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
 		task_dirty_inc(current);
 		task_io_account_write(PAGE_CACHE_SIZE);
@@ -1129,6 +1124,18 @@ void account_page_dirtied(struct page *page, struct address_space *mapping)
 EXPORT_SYMBOL(account_page_dirtied);
 
 /*
+ * Helper function for set_page_writeback family.
+ * NOTE: Unlike account_page_dirtied this does not rely on being atomic
+ * wrt interrupts.
+ */
+void account_page_writeback(struct page *page)
+{
+	inc_zone_page_state(page, NR_WRITEBACK);
+	inc_zone_page_state(page, NR_WRITTEN);
+}
+EXPORT_SYMBOL(account_page_writeback);
+
+/*
  * For address_spaces which do not use buffers.  Just tag the page as dirty in
  * its radix tree.
  *
@@ -1366,7 +1373,7 @@ int test_set_page_writeback(struct page *page)
 		ret = TestSetPageWriteback(page);
 	}
 	if (!ret)
-		inc_zone_page_state(page, NR_WRITEBACK);
+		account_page_writeback(page);
 	return ret;
 
 }