From ece13ac31bbe492d940ba0bc4ade2ae1521f46a5 Mon Sep 17 00:00:00 2001
From: Wu Fengguang <fengguang.wu@intel.com>
Date: Sun, 29 Aug 2010 23:33:20 -0600
Subject: writeback: trace event balance_dirty_pages
Useful for analyzing the dynamics of the throttling algorithms and
debugging user reported problems.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
---
mm/page-writeback.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
(limited to 'mm')
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index e3c2d8b..45d36f7 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1103,12 +1103,34 @@ static void balance_dirty_pages(struct address_space *mapping,
pos_ratio >> RATELIMIT_CALC_SHIFT;
pause = (HZ * pages_dirtied) / (task_ratelimit | 1);
if (unlikely(pause <= 0)) {
+ trace_balance_dirty_pages(bdi,
+ dirty_thresh,
+ background_thresh,
+ nr_dirty,
+ bdi_thresh,
+ bdi_dirty,
+ dirty_ratelimit,
+ task_ratelimit,
+ pages_dirtied,
+ pause,
+ start_time);
pause = 1; /* avoid resetting nr_dirtied_pause below */
break;
}
pause = min(pause, max_pause);
pause:
+ trace_balance_dirty_pages(bdi,
+ dirty_thresh,
+ background_thresh,
+ nr_dirty,
+ bdi_thresh,
+ bdi_dirty,
+ dirty_ratelimit,
+ task_ratelimit,
+ pages_dirtied,
+ pause,
+ start_time);
__set_current_state(TASK_UNINTERRUPTIBLE);
io_schedule_timeout(pause);
--
cgit v1.1