[PATCH v3 12/12] ext4: add two trace points for moving extents

[Zhang Yi <yi.zhang@huaweicloud.com>]

From: Zhang Yi <yi.zhang@huawei.com>

To facilitate tracking the length, type, and outcome of the move extent,
add a trace point at both the entry and exit of mext_move_extent().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 fs/ext4/move_extent.c       | 14 ++++++-
 include/trace/events/ext4.h | 74 +++++++++++++++++++++++++++++++++++++
 2 files changed, 86 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
index 691edcf5d464..87f21a30a82a 100644
--- a/fs/ext4/move_extent.c
+++ b/fs/ext4/move_extent.c
@@ -13,6 +13,8 @@
 #include "ext4.h"
 #include "ext4_extents.h"
 
+#include <trace/events/ext4.h>
+
 struct mext_data {
 	struct inode *orig_inode;	/* Origin file inode */
 	struct inode *donor_inode;	/* Donor file inode */
@@ -311,10 +313,14 @@ static int mext_move_extent(struct mext_data *mext, u64 *m_len)
 	int ret, ret2;
 
 	*m_len = 0;
+	trace_ext4_move_extent_enter(orig_inode, orig_map, donor_inode,
+				     mext->donor_lblk);
 	credits = ext4_chunk_trans_extent(orig_inode, 0) * 2;
 	handle = ext4_journal_start(orig_inode, EXT4_HT_MOVE_EXTENTS, credits);
-	if (IS_ERR(handle))
-		return PTR_ERR(handle);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		goto out;
+	}
 
 	ret = mext_move_begin(mext, folio, &move_type);
 	if (ret)
@@ -374,6 +380,10 @@ static int mext_move_extent(struct mext_data *mext, u64 *m_len)
 	mext_folio_double_unlock(folio);
 stop_handle:
 	ext4_journal_stop(handle);
+out:
+	trace_ext4_move_extent_exit(orig_inode, orig_map->m_lblk, donor_inode,
+				    mext->donor_lblk, orig_map->m_len, *m_len,
+				    move_type, ret);
 	return ret;
 
 repair_branches:
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index 6a0754d38acf..a05bdd48e16e 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -3016,6 +3016,80 @@ TRACE_EVENT(ext4_update_sb,
 		  __entry->fsblk, __entry->flags)
 );
 
+TRACE_EVENT(ext4_move_extent_enter,
+	TP_PROTO(struct inode *orig_inode, struct ext4_map_blocks *orig_map,
+		 struct inode *donor_inode, ext4_lblk_t donor_lblk),
+
+	TP_ARGS(orig_inode, orig_map, donor_inode, donor_lblk),
+
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__field(ino_t, orig_ino)
+		__field(ext4_lblk_t, orig_lblk)
+		__field(unsigned int, orig_flags)
+		__field(ino_t, donor_ino)
+		__field(ext4_lblk_t, donor_lblk)
+		__field(unsigned int, len)
+	),
+
+	TP_fast_assign(
+		__entry->dev		= orig_inode->i_sb->s_dev;
+		__entry->orig_ino	= orig_inode->i_ino;
+		__entry->orig_lblk	= orig_map->m_lblk;
+		__entry->orig_flags	= orig_map->m_flags;
+		__entry->donor_ino	= donor_inode->i_ino;
+		__entry->donor_lblk	= donor_lblk;
+		__entry->len		= orig_map->m_len;
+	),
+
+	TP_printk("dev %d,%d origin ino %lu lblk %u flags %s donor ino %lu lblk %u len %u",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  (unsigned long) __entry->orig_ino,  __entry->orig_lblk,
+		  show_mflags(__entry->orig_flags),
+		  (unsigned long) __entry->donor_ino,  __entry->donor_lblk,
+		  __entry->len)
+);
+
+TRACE_EVENT(ext4_move_extent_exit,
+	TP_PROTO(struct inode *orig_inode, ext4_lblk_t orig_lblk,
+		 struct inode *donor_inode, ext4_lblk_t donor_lblk,
+		 unsigned int m_len, u64 move_len, int move_type, int ret),
+
+	TP_ARGS(orig_inode, orig_lblk, donor_inode, donor_lblk, m_len,
+		move_len, move_type, ret),
+
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__field(ino_t, orig_ino)
+		__field(ext4_lblk_t, orig_lblk)
+		__field(ino_t, donor_ino)
+		__field(ext4_lblk_t, donor_lblk)
+		__field(unsigned int, m_len)
+		__field(u64, move_len)
+		__field(int, move_type)
+		__field(int, ret)
+	),
+
+	TP_fast_assign(
+		__entry->dev		= orig_inode->i_sb->s_dev;
+		__entry->orig_ino	= orig_inode->i_ino;
+		__entry->orig_lblk	= orig_lblk;
+		__entry->donor_ino	= donor_inode->i_ino;
+		__entry->donor_lblk	= donor_lblk;
+		__entry->m_len		= m_len;
+		__entry->move_len	= move_len;
+		__entry->move_type	= move_type;
+		__entry->ret		= ret;
+	),
+
+	TP_printk("dev %d,%d origin ino %lu lblk %u donor ino %lu lblk %u m_len %u, move_len %llu type %d ret %d",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  (unsigned long) __entry->orig_ino,  __entry->orig_lblk,
+		  (unsigned long) __entry->donor_ino,  __entry->donor_lblk,
+		  __entry->m_len, __entry->move_len, __entry->move_type,
+		  __entry->ret)
+);
+
 #endif /* _TRACE_EXT4_H */
 
 /* This part must be outside protection */
-- 
2.46.1