From ece13ac31bbe492d940ba0bc4ade2ae1521f46a5 Mon Sep 17 00:00:00 2001 From: Wu Fengguang 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 --- mm/page-writeback.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'mm/page-writeback.c') diff --git a/mm/page-writeback.c b/mm/page-writeback.c index e3c2d8bf87bb..45d36f7dc169 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 v1.2.3-55-g7522