[PATCH 2/2] ext4: Fix extent_status trace events

[Dmitry Monakhov <dmonakhov@xxxxxxxxx>]

 - show pblock only if it has meaningful value
 - Add missed EXTENT_STATUS_REFERENCED decoder
 - Define status flags as explicit numbers instead of implicit enum ones

# before
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [1/4294967294) 576460752303423487 0x8
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [2/4294967293) 576460752303423487 0x18
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [3/4294967292) 576460752303423487 0x18
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [4/4294967291) 576460752303423487 0x18
# after
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [1/4294967294) 0 H
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [2/4294967293) 0 HR
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [3/4294967292) 0 HR
   ext4:ext4_es_lookup_extent_exit: dev 253,0 ino 12 found 1 [4/4294967291) 0 HR

Signed-off-by: Dmitry Monakhov <dmonakhov@xxxxxxxxx>
---
 fs/ext4/extents_status.h    | 21 +++++++++++++--------
 include/trace/events/ext4.h | 11 ++++++-----
 2 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/fs/ext4/extents_status.h b/fs/ext4/extents_status.h
index 131a8b7..64b8fd1 100644
--- a/fs/ext4/extents_status.h
+++ b/fs/ext4/extents_status.h
@@ -30,14 +30,13 @@
 /*
  * These flags live in the high bits of extent_status.es_pblk
  */
-enum {
-	ES_WRITTEN_B,
-	ES_UNWRITTEN_B,
-	ES_DELAYED_B,
-	ES_HOLE_B,
-	ES_REFERENCED_B,
-	ES_FLAGS
-};
+
+#define ES_WRITTEN_B     0
+#define ES_UNWRITTEN_B   1
+#define ES_DELAYED_B     2
+#define ES_HOLE_B        3
+#define ES_REFERENCED_B  4
+#define ES_FLAGS         5
 
 #define ES_SHIFT (sizeof(ext4_fsblk_t)*8 - ES_FLAGS)
 #define ES_MASK (~((ext4_fsblk_t)0) << ES_SHIFT)
@@ -208,6 +207,12 @@ static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es)
 	return es->es_pblk & ~ES_MASK;
 }
 
+static inline ext4_fsblk_t ext4_es_show_pblock(struct extent_status *es)
+{
+	ext4_fsblk_t pblock = ext4_es_pblock(es);
+	return pblock == ~ES_MASK ? 0 : pblock;
+}
+
 static inline void ext4_es_store_pblock(struct extent_status *es,
 					ext4_fsblk_t pb)
 {
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index d68e9e5..bdb5fc4 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -66,7 +66,8 @@ struct partial_cluster;
 	{ EXTENT_STATUS_WRITTEN,	"W" },			\
 	{ EXTENT_STATUS_UNWRITTEN,	"U" },			\
 	{ EXTENT_STATUS_DELAYED,	"D" },			\
-	{ EXTENT_STATUS_HOLE,		"H" })
+	{ EXTENT_STATUS_HOLE,		"H" },			\
+	{ EXTENT_STATUS_REFERENCED,	"R" })
 
 #define show_falloc_mode(mode) __print_flags(mode, "|",		\
 	{ FALLOC_FL_KEEP_SIZE,		"KEEP_SIZE"},		\
@@ -2262,7 +2263,7 @@ DECLARE_EVENT_CLASS(ext4__es_extent,
 		__entry->ino	= inode->i_ino;
 		__entry->lblk	= es->es_lblk;
 		__entry->len	= es->es_len;
-		__entry->pblk	= ext4_es_pblock(es);
+		__entry->pblk	= ext4_es_show_pblock(es);
 		__entry->status	= ext4_es_status(es);
 	),
 
@@ -2351,7 +2352,7 @@ TRACE_EVENT(ext4_es_find_extent_range_exit,
 		__entry->ino	= inode->i_ino;
 		__entry->lblk	= es->es_lblk;
 		__entry->len	= es->es_len;
-		__entry->pblk	= ext4_es_pblock(es);
+		__entry->pblk	= ext4_es_show_pblock(es);
 		__entry->status	= ext4_es_status(es);
 	),
 
@@ -2405,7 +2406,7 @@ TRACE_EVENT(ext4_es_lookup_extent_exit,
 		__entry->ino	= inode->i_ino;
 		__entry->lblk	= es->es_lblk;
 		__entry->len	= es->es_len;
-		__entry->pblk	= ext4_es_pblock(es);
+		__entry->pblk	= ext4_es_show_pblock(es);
 		__entry->status	= ext4_es_status(es);
 		__entry->found	= found;
 	),
@@ -2573,7 +2574,7 @@ TRACE_EVENT(ext4_es_insert_delayed_block,
 		__entry->ino		= inode->i_ino;
 		__entry->lblk		= es->es_lblk;
 		__entry->len		= es->es_len;
-		__entry->pblk		= ext4_es_pblock(es);
+		__entry->pblk		= ext4_es_show_pblock(es);
 		__entry->status		= ext4_es_status(es);
 		__entry->allocated	= allocated;
 	),
-- 
2.7.4