1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef DM_STATS_H
3*4882a593Smuzhiyun #define DM_STATS_H
4*4882a593Smuzhiyun
5*4882a593Smuzhiyun #include <linux/types.h>
6*4882a593Smuzhiyun #include <linux/mutex.h>
7*4882a593Smuzhiyun #include <linux/list.h>
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun int dm_statistics_init(void);
10*4882a593Smuzhiyun void dm_statistics_exit(void);
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun struct dm_stats {
13*4882a593Smuzhiyun struct mutex mutex;
14*4882a593Smuzhiyun struct list_head list; /* list of struct dm_stat */
15*4882a593Smuzhiyun struct dm_stats_last_position __percpu *last;
16*4882a593Smuzhiyun sector_t last_sector;
17*4882a593Smuzhiyun unsigned last_rw;
18*4882a593Smuzhiyun };
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun struct dm_stats_aux {
21*4882a593Smuzhiyun bool merged;
22*4882a593Smuzhiyun unsigned long long duration_ns;
23*4882a593Smuzhiyun };
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun void dm_stats_init(struct dm_stats *st);
26*4882a593Smuzhiyun void dm_stats_cleanup(struct dm_stats *st);
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun struct mapped_device;
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun int dm_stats_message(struct mapped_device *md, unsigned argc, char **argv,
31*4882a593Smuzhiyun char *result, unsigned maxlen);
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun void dm_stats_account_io(struct dm_stats *stats, unsigned long bi_rw,
34*4882a593Smuzhiyun sector_t bi_sector, unsigned bi_sectors, bool end,
35*4882a593Smuzhiyun unsigned long duration_jiffies,
36*4882a593Smuzhiyun struct dm_stats_aux *aux);
37*4882a593Smuzhiyun
dm_stats_used(struct dm_stats * st)38*4882a593Smuzhiyun static inline bool dm_stats_used(struct dm_stats *st)
39*4882a593Smuzhiyun {
40*4882a593Smuzhiyun return !list_empty(&st->list);
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun #endif
44