[PATCH] xfs: record whichfork in iext tracepoints

["Darrick J. Wong" <darrick.wong@oracle.com>]

From: Darrick J. Wong <darrick.wong@oracle.com>

Record the whichfork number of the fork being operated on in iext
tracepoints.  This makes it easier to trace our way through complex
remapping operations like copy on write.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_trace.h |   15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index cd87985..1c38b79 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -233,6 +233,7 @@ DECLARE_EVENT_CLASS(xfs_bmap_class,
 		__field(xfs_exntst_t, state)
 		__field(int, bmap_state)
 		__field(unsigned long, caller_ip)
+		__field(int, whichfork)
 	),
 	TP_fast_assign(
 		struct xfs_ifork	*ifp;
@@ -250,11 +251,19 @@ DECLARE_EVENT_CLASS(xfs_bmap_class,
 		__entry->state = r.br_state;
 		__entry->bmap_state = state;
 		__entry->caller_ip = caller_ip;
-	),
-	TP_printk("dev %d:%d ino 0x%llx state %s cur 0x%p/%d "
+		if (ifp == XFS_IFORK_PTR(ip, XFS_DATA_FORK))
+			__entry->whichfork = XFS_DATA_FORK;
+		else if (ifp == XFS_IFORK_PTR(ip, XFS_ATTR_FORK))
+			__entry->whichfork = XFS_ATTR_FORK;
+		else if (ifp == XFS_IFORK_PTR(ip, XFS_COW_FORK))
+			__entry->whichfork = XFS_COW_FORK;
+		else
+			__entry->whichfork = -1;
+	),
+	TP_printk("dev %d:%d ino 0x%llx fork %d state %s cur 0x%p/%d "
 		  "offset %lld block %lld count %lld flag %d caller %ps",
 		  MAJOR(__entry->dev), MINOR(__entry->dev),
-		  __entry->ino,
+		  __entry->ino, __entry->whichfork,
 		  __print_flags(__entry->bmap_state, "|", XFS_BMAP_EXT_FLAGS),
 		  __entry->leaf,
 		  __entry->pos,