btrfs: Add ftrace for btrfs_workqueue

Add ftrace for btrfs_workqueue for further workqueue tunning.
This patch needs to applied after the workqueue replace patchset.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>

2 files changed, 89 insertions, 0 deletions

diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index d8c07e5c1f24..00623dd16b81 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -24,6 +24,7 @@
 #include <linux/freezer.h>
 #include <linux/workqueue.h>
 #include "async-thread.h"
+#include "ctree.h"
 
 #define WORK_DONE_BIT 0
 #define WORK_ORDER_DONE_BIT 1
@@ -210,6 +211,7 @@ static void run_ordered_work(struct __btrfs_workqueue *wq)
                  */
                 if (test_and_set_bit(WORK_ORDER_DONE_BIT, &work->flags))
                         break;
+                trace_btrfs_ordered_sched(work);
                 spin_unlock_irqrestore(lock, flags);
                 work->ordered_func(work);
 
@@ -223,6 +225,7 @@ static void run_ordered_work(struct __btrfs_workqueue *wq)
                  * with the lock held though
                  */
                 work->ordered_free(work);
+                trace_btrfs_all_work_done(work);
         }
         spin_unlock_irqrestore(lock, flags);
 }
@@ -246,12 +249,15 @@ static void normal_work_helper(struct work_struct *arg)
                 need_order = 1;
         wq = work->wq;
 
+        trace_btrfs_work_sched(work);
         thresh_exec_hook(wq);
         work->func(work);
         if (need_order) {
                 set_bit(WORK_DONE_BIT, &work->flags);
                 run_ordered_work(wq);
         }
+        if (!need_order)
+                trace_btrfs_all_work_done(work);
 }
 
 void btrfs_init_work(struct btrfs_work *work,
@@ -280,6 +286,7 @@ static inline void __btrfs_queue_work(struct __btrfs_workqueue *wq,
                 spin_unlock_irqrestore(&wq->list_lock, flags);
         }
         queue_work(wq->normal_wq, &work->normal_work);
+        trace_btrfs_work_queued(work);
 }
 
 void btrfs_queue_work(struct btrfs_workqueue *wq,
diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h
index 3176cdc32937..c346919254a9 100644
--- a/include/trace/events/btrfs.h
+++ b/include/trace/events/btrfs.h
@@ -21,6 +21,7 @@ struct btrfs_block_group_cache;
 struct btrfs_free_cluster;
 struct map_lookup;
 struct extent_buffer;
+struct btrfs_work;
 
 #define show_ref_type(type)                                             \
         __print_symbolic(type,                                          \
@@ -982,6 +983,87 @@ TRACE_EVENT(free_extent_state,
                   (void *)__entry->ip)
 );
 
+DECLARE_EVENT_CLASS(btrfs__work,
+
+        TP_PROTO(struct btrfs_work *work),
+
+        TP_ARGS(work),
+
+        TP_STRUCT__entry(
+                __field(        void *, work                    )
+                __field(        void *, wq                      )
+                __field(        void *, func                    )
+                __field(        void *, ordered_func            )
+                __field(        void *, ordered_free            )
+        ),
+
+        TP_fast_assign(
+                __entry->work           = work;
+                __entry->wq             = work->wq;
+                __entry->func           = work->func;
+                __entry->ordered_func   = work->ordered_func;
+                __entry->ordered_free   = work->ordered_free;
+        ),
+
+        TP_printk("work=%p, wq=%p, func=%p, ordered_func=%p, ordered_free=%p",
+                  __entry->work, __entry->wq, __entry->func,
+                  __entry->ordered_func, __entry->ordered_free)
+);
+
+/* For situiations that the work is freed */
+DECLARE_EVENT_CLASS(btrfs__work__done,
+
+        TP_PROTO(struct btrfs_work *work),
+
+        TP_ARGS(work),
+
+        TP_STRUCT__entry(
+                __field(        void *, work                    )
+        ),
+
+        TP_fast_assign(
+                __entry->work           = work;
+        ),
+
+        TP_printk("work->%p", __entry->work)
+);
+
+DEFINE_EVENT(btrfs__work, btrfs_work_queued,
+
+        TP_PROTO(struct btrfs_work *work),
+
+        TP_ARGS(work)
+);
+
+DEFINE_EVENT(btrfs__work, btrfs_work_sched,
+
+        TP_PROTO(struct btrfs_work *work),
+
+        TP_ARGS(work)
+);
+
+DEFINE_EVENT(btrfs__work, btrfs_normal_work_done,
+
+        TP_PROTO(struct btrfs_work *work),
+
+        TP_ARGS(work)
+);
+
+DEFINE_EVENT(btrfs__work__done, btrfs_all_work_done,
+
+        TP_PROTO(struct btrfs_work *work),
+
+        TP_ARGS(work)
+);
+
+DEFINE_EVENT(btrfs__work, btrfs_ordered_sched,
+
+        TP_PROTO(struct btrfs_work *work),
+
+        TP_ARGS(work)
+);
+
+
 #endif /* _TRACE_BTRFS_H */
 
 /* This part must be outside protection */