From: From: Jens Axboe <jens.axboe@oracle.com>

Trace queue/sched/exec parts of the writeback loop.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
 fs/fs-writeback.c                |   51 +++++-------
 include/linux/writeback.h        |   27 ++++++
 include/trace/events/writeback.h |  171 ++++++++++++++++++++++++++++++++++++++
 mm/backing-dev.c                 |    5 +
 4 files changed, 224 insertions(+), 30 deletions(-)
 create mode 100644 include/trace/events/writeback.h

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 76fc4d5..3f5f0a5 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -25,7 +25,9 @@
 #include <linux/blkdev.h>
 #include <linux/backing-dev.h>
 #include <linux/buffer_head.h>
+#include <linux/ftrace.h>
 #include "internal.h"
+#include <trace/events/writeback.h>
 
 #define inode_to_bdi(inode)	((inode)->i_mapping->backing_dev_info)
 
@@ -34,33 +36,6 @@
  */
 int nr_pdflush_threads;
 
-/*
- * Passed into wb_writeback(), essentially a subset of writeback_control
- */
-struct wb_writeback_args {
-	long nr_pages;
-	struct super_block *sb;
-	enum writeback_sync_modes sync_mode;
-	int for_kupdate:1;
-	int range_cyclic:1;
-	int for_background:1;
-};
-
-/*
- * Work items for the bdi_writeback threads
- */
-struct bdi_work {
-	struct list_head list;		/* pending work list */
-	struct rcu_head rcu_head;	/* for RCU free/clear of work */
-
-	unsigned long seen;		/* threads that have seen this work */
-	atomic_t pending;		/* number of threads still to do work */
-
-	struct wb_writeback_args args;	/* writeback arguments */
-
-	unsigned long state;		/* flag bits, see WS_* */
-};
-
 enum {
 	WS_USED_B = 0,
 	WS_ONSTACK_B,
@@ -135,6 +110,8 @@ static void wb_work_complete(struct bdi_work *work)
 
 static void wb_clear_pending(struct bdi_writeback *wb, struct bdi_work *work)
 {
+	trace_writeback_clear(work);
+
 	/*
 	 * The caller has retrieved the work arguments from this ...
[ message continues ]

If you move the CREATE_TRACE_POINTS into fs-writeback.c and include
<trace/events/writeback.h> after the sturcture defintions there's no
need to move them to a header.

--

[ message continues ]