49 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			49 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef DM_STATS_H
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| #define DM_STATS_H
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| 
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| #include <linux/types.h>
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| #include <linux/mutex.h>
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| #include <linux/list.h>
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| 
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| int dm_statistics_init(void);
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| void dm_statistics_exit(void);
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| 
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| struct dm_stats {
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| 	struct mutex mutex;
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| 	struct list_head list;	/* list of struct dm_stat */
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| 	struct dm_stats_last_position __percpu *last;
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| 	bool precise_timestamps;
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| };
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| 
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| struct dm_stats_aux {
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| 	bool merged;
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| 	unsigned long long duration_ns;
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| };
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| 
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| int dm_stats_init(struct dm_stats *st);
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| void dm_stats_cleanup(struct dm_stats *st);
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| 
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| struct mapped_device;
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| 
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| int dm_stats_message(struct mapped_device *md, unsigned int argc, char **argv,
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| 		     char *result, unsigned int maxlen);
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| 
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| void dm_stats_account_io(struct dm_stats *stats, unsigned long bi_rw,
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| 			 sector_t bi_sector, unsigned int bi_sectors, bool end,
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| 			 unsigned long start_time,
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| 			 struct dm_stats_aux *aux);
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| 
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| static inline bool dm_stats_used(struct dm_stats *st)
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| {
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| 	return !list_empty(&st->list);
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| }
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| 
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| static inline void dm_stats_record_start(struct dm_stats *stats, struct dm_stats_aux *aux)
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| {
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| 	if (unlikely(stats->precise_timestamps))
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| 		aux->duration_ns = ktime_to_ns(ktime_get());
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| }
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| 
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| #endif
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