1 #ifndef __TRACE_STAT_H
2 #define __TRACE_STAT_H
3 
4 #include <linux/seq_file.h>
5 
6 /*
7  * If you want to provide a stat file (one-shot statistics), fill
8  * an iterator with stat_start/stat_next and a stat_show callbacks.
9  * The others callbacks are optional.
10  */
11 struct tracer_stat {
12 	/* The name of your stat file */
13 	const char		*name;
14 	/* Iteration over statistic entries */
15 	void			*(*stat_start)(struct tracer_stat *trace);
16 	void			*(*stat_next)(void *prev, int idx);
17 	/* Compare two entries for stats sorting */
18 	int			(*stat_cmp)(void *p1, void *p2);
19 	/* Print a stat entry */
20 	int			(*stat_show)(struct seq_file *s, void *p);
21 	/* Release an entry */
22 	void			(*stat_release)(void *stat);
23 	/* Print the headers of your stat entries */
24 	int			(*stat_headers)(struct seq_file *s);
25 };
26 
27 /*
28  * Destroy or create a stat file
29  */
30 extern int register_stat_tracer(struct tracer_stat *trace);
31 extern void unregister_stat_tracer(struct tracer_stat *trace);
32 
33 #endif /* __TRACE_STAT_H */
34