[PATCH 10/15] writeback: add bdi_dirty_limit() kernel-doc

Wu Fengguang
2011-06-07T21:47:33Z

[-- Attachment #1: writeback-task_dirty_limit-comment.patch --]
[-- Type: text/plain, Size: 1193 bytes --]

Clarify the bdi_dirty_limit() comment.

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
---
mm/page-writeback.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

--- linux-next.orig/mm/page-writeback.c 2011-05-24 11:17:14.000000000 +0800
+++ linux-next/mm/page-writeback.c 2011-05-24 11:17:23.000000000 +0800
@@ -437,10 +437,17 @@ void global_dirty_limits(unsigned long *
*pdirty = dirty;
}

-/*
+/**
* bdi_dirty_limit - @bdi's share of dirty throttling threshold
+ * @bdi: the backing_dev_info to query
+ * @dirty: global dirty limit in pages
+ *
+ * Returns @bdi's dirty limit in pages. The term "dirty" in the context of
+ * dirty balancing includes all PG_dirty, PG_writeback and NFS unstable pages.
+ * And the "limit" in the name is not seriously taken as hard limit in
+ * balance_dirty_pages().
*
- * Allocate high/low dirty limits to fast/slow devices, in order to prevent
+ * It allocates high/low dirty limits to fast/slow devices, in order to prevent
* - starving fast devices
* - piling up dirty pages (that will take long time to sync) on slow devices
*