1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_PART_STAT_H
3 #define _LINUX_PART_STAT_H
4 
5 #include <linux/genhd.h>
6 #include <asm/local.h>
7 
8 struct disk_stats {
9 	u64 nsecs[NR_STAT_GROUPS];
10 	unsigned long sectors[NR_STAT_GROUPS];
11 	unsigned long ios[NR_STAT_GROUPS];
12 	unsigned long merges[NR_STAT_GROUPS];
13 	unsigned long io_ticks;
14 	local_t in_flight[2];
15 };
16 
17 /*
18  * Macros to operate on percpu disk statistics:
19  *
20  * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters and should
21  * be called between disk_stat_lock() and disk_stat_unlock().
22  *
23  * part_stat_read() can be called at any time.
24  */
25 #define part_stat_lock()	preempt_disable()
26 #define part_stat_unlock()	preempt_enable()
27 
28 #define part_stat_get_cpu(part, field, cpu)				\
29 	(per_cpu_ptr((part)->bd_stats, (cpu))->field)
30 
31 #define part_stat_get(part, field)					\
32 	part_stat_get_cpu(part, field, smp_processor_id())
33 
34 #define part_stat_read(part, field)					\
35 ({									\
36 	typeof((part)->bd_stats->field) res = 0;			\
37 	unsigned int _cpu;						\
38 	for_each_possible_cpu(_cpu)					\
39 		res += per_cpu_ptr((part)->bd_stats, _cpu)->field; \
40 	res;								\
41 })
42 
part_stat_set_all(struct block_device * part,int value)43 static inline void part_stat_set_all(struct block_device *part, int value)
44 {
45 	int i;
46 
47 	for_each_possible_cpu(i)
48 		memset(per_cpu_ptr(part->bd_stats, i), value,
49 				sizeof(struct disk_stats));
50 }
51 
52 #define part_stat_read_accum(part, field)				\
53 	(part_stat_read(part, field[STAT_READ]) +			\
54 	 part_stat_read(part, field[STAT_WRITE]) +			\
55 	 part_stat_read(part, field[STAT_DISCARD]))
56 
57 #define __part_stat_add(part, field, addnd)				\
58 	__this_cpu_add((part)->bd_stats->field, addnd)
59 
60 #define part_stat_add(part, field, addnd)	do {			\
61 	__part_stat_add((part), field, addnd);				\
62 	if ((part)->bd_partno)						\
63 		__part_stat_add(bdev_whole(part), field, addnd);	\
64 } while (0)
65 
66 #define part_stat_dec(part, field)					\
67 	part_stat_add(part, field, -1)
68 #define part_stat_inc(part, field)					\
69 	part_stat_add(part, field, 1)
70 #define part_stat_sub(part, field, subnd)				\
71 	part_stat_add(part, field, -subnd)
72 
73 #define part_stat_local_dec(part, field)				\
74 	local_dec(&(part_stat_get(part, field)))
75 #define part_stat_local_inc(part, field)				\
76 	local_inc(&(part_stat_get(part, field)))
77 #define part_stat_local_read(part, field)				\
78 	local_read(&(part_stat_get(part, field)))
79 #define part_stat_local_read_cpu(part, field, cpu)			\
80 	local_read(&(part_stat_get_cpu(part, field, cpu)))
81 
82 #endif /* _LINUX_PART_STAT_H */
83