bcachefs: Add tracepoints for bch2_sync_fs() and bch2_fsync()

Add trace_bch2_sync_fs() and trace_bch2_fsync() implementations.

The output in trace is as follows:
  sync-29779   [000] .....   193.700935: bch2_sync_fs: dev 254,16 wait 1
  <...>-40027  [002] .....   342.535227: bch2_fsync: dev 254,32 ino 4099 parent 4096 datasync 1
Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/fs-io.c

@@ -194,6 +194,8 @@ int bch2_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 	struct bch_fs *c = inode->v.i_sb->s_fs_info;
 	int ret, err;
 
+	trace_bch2_fsync(file, datasync);
+
 	ret = file_write_and_wait_range(file, start, end);
 	if (ret)
 		goto out;

fs/bcachefs/fs.c

@@ -26,6 +26,7 @@
 #include "snapshot.h"
 #include "super.h"
 #include "xattr.h"
+#include "trace.h"
 
 #include <linux/aio.h>
 #include <linux/backing-dev.h>
@@ -1697,6 +1698,8 @@ static int bch2_sync_fs(struct super_block *sb, int wait)
 	struct bch_fs *c = sb->s_fs_info;
 	int ret;
 
+	trace_bch2_sync_fs(sb, wait);
+
 	if (c->opts.journal_flush_disabled)
 		return 0;
 

fs/bcachefs/trace.h

@@ -200,6 +200,56 @@ DECLARE_EVENT_CLASS(bio,
 		  (unsigned long long)__entry->sector, __entry->nr_sector)
 );
 
+/* fs.c: */
+TRACE_EVENT(bch2_sync_fs,
+	TP_PROTO(struct super_block *sb, int wait),
+
+	TP_ARGS(sb, wait),
+
+	TP_STRUCT__entry(
+		__field(	dev_t,	dev			)
+		__field(	int,	wait			)
+
+	),
+
+	TP_fast_assign(
+		__entry->dev	= sb->s_dev;
+		__entry->wait	= wait;
+	),
+
+	TP_printk("dev %d,%d wait %d",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->wait)
+);
+
+/* fs-io.c: */
+TRACE_EVENT(bch2_fsync,
+	TP_PROTO(struct file *file, int datasync),
+
+	TP_ARGS(file, datasync),
+
+	TP_STRUCT__entry(
+		__field(	dev_t,	dev			)
+		__field(	ino_t,	ino			)
+		__field(	ino_t,	parent			)
+		__field(	int,	datasync		)
+	),
+
+	TP_fast_assign(
+		struct dentry *dentry = file->f_path.dentry;
+
+		__entry->dev		= dentry->d_sb->s_dev;
+		__entry->ino		= d_inode(dentry)->i_ino;
+		__entry->parent		= d_inode(dentry->d_parent)->i_ino;
+		__entry->datasync	= datasync;
+	),
+
+	TP_printk("dev %d,%d ino %lu parent %lu datasync %d ",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  (unsigned long) __entry->ino,
+		  (unsigned long) __entry->parent, __entry->datasync)
+);
+
 /* super-io.c: */
 TRACE_EVENT(write_super,
 	TP_PROTO(struct bch_fs *c, unsigned long ip),