2 files changed, 24 insertions, 13 deletions

diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index 63d197724519..ff0b0be92d61 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -273,6 +273,8 @@ static void run_ordered_work(struct __btrfs_workqueue *wq)
         unsigned long flags;
 
         while (1) {
+                void *wtag;
+
                 spin_lock_irqsave(lock, flags);
                 if (list_empty(list))
                         break;
@@ -299,11 +301,13 @@ static void run_ordered_work(struct __btrfs_workqueue *wq)
                 spin_unlock_irqrestore(lock, flags);
 
                 /*
-                 * we don't want to call the ordered free functions
-                 * with the lock held though
+                 * We don't want to call the ordered free functions with the
+                 * lock held though. Save the work as tag for the trace event,
+                 * because the callback could free the structure.
                  */
+                wtag = work;
                 work->ordered_free(work);
-                trace_btrfs_all_work_done(work);
+                trace_btrfs_all_work_done(wq->fs_info, wtag);
         }
         spin_unlock_irqrestore(lock, flags);
 }
@@ -311,6 +315,7 @@ static void run_ordered_work(struct __btrfs_workqueue *wq)
 static void normal_work_helper(struct btrfs_work *work)
 {
         struct __btrfs_workqueue *wq;
+        void *wtag;
         int need_order = 0;
 
         /*
@@ -324,6 +329,8 @@ static void normal_work_helper(struct btrfs_work *work)
         if (work->ordered_func)
                 need_order = 1;
         wq = work->wq;
+        /* Safe for tracepoints in case work gets freed by the callback */
+        wtag = work;
 
         trace_btrfs_work_sched(work);
         thresh_exec_hook(wq);
@@ -333,7 +340,7 @@ static void normal_work_helper(struct btrfs_work *work)
                 run_ordered_work(wq);
         }
         if (!need_order)
-                trace_btrfs_all_work_done(work);
+                trace_btrfs_all_work_done(wq->fs_info, wtag);
 }
 
 void btrfs_init_work(struct btrfs_work *work, btrfs_work_func_t uniq_func,
diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h
index e030d6f6c19a..6d7fe1169956 100644
--- a/include/trace/events/btrfs.h
+++ b/include/trace/events/btrfs.h
@@ -1162,22 +1162,26 @@ DECLARE_EVENT_CLASS(btrfs__work,
                    __entry->func, __entry->ordered_func, __entry->ordered_free)
 );
 
-/* For situiations that the work is freed */
+/*
+ * For situiations when the work is freed, we pass fs_info and a tag that that
+ * matches address of the work structure so it can be paired with the
+ * scheduling event.
+ */
 DECLARE_EVENT_CLASS(btrfs__work__done,
 
-        TP_PROTO(struct btrfs_work *work),
+        TP_PROTO(struct btrfs_fs_info *fs_info, void *wtag),
 
-        TP_ARGS(work),
+        TP_ARGS(fs_info, wtag),
 
         TP_STRUCT__entry_btrfs(
-                __field(        void *, work                    )
+                __field(        void *, wtag                    )
         ),
 
-        TP_fast_assign_btrfs(btrfs_work_owner(work),
-                __entry->work           = work;
+        TP_fast_assign_btrfs(fs_info,
+                __entry->wtag           = wtag;
         ),
 
-        TP_printk_btrfs("work->%p", __entry->work)
+        TP_printk_btrfs("work->%p", __entry->wtag)
 );
 
 DEFINE_EVENT(btrfs__work, btrfs_work_queued,
@@ -1196,9 +1200,9 @@ DEFINE_EVENT(btrfs__work, btrfs_work_sched,
 
 DEFINE_EVENT(btrfs__work__done, btrfs_all_work_done,
 
-        TP_PROTO(struct btrfs_work *work),
+        TP_PROTO(struct btrfs_fs_info *fs_info, void *wtag),
 
-        TP_ARGS(work)
+        TP_ARGS(fs_info, wtag)
 );
 
 DEFINE_EVENT(btrfs__work, btrfs_ordered_sched,