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