include/linux/part_stat.h

   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
   7 struct disk_stats {
   8         u64 nsecs[NR_STAT_GROUPS];
   9         unsigned long sectors[NR_STAT_GROUPS];
  10         unsigned long ios[NR_STAT_GROUPS];
  11         unsigned long merges[NR_STAT_GROUPS];
  12         unsigned long io_ticks;
  13         local_t in_flight[2];
  14 };
  15
  16 /*
  17  * Macros to operate on percpu disk statistics:
  18  *
  19  * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters and should
  20  * be called between disk_stat_lock() and disk_stat_unlock().
  21  *
  22  * part_stat_read() can be called at any time.
  23  */
  24 #define part_stat_lock()        preempt_disable()
  25 #define part_stat_unlock()      preempt_enable()
  26
  27 #define part_stat_get_cpu(part, field, cpu)                             \
  28         (per_cpu_ptr((part)->dkstats, (cpu))->field)
  29
  30 #define part_stat_get(part, field)                                      \
  31         part_stat_get_cpu(part, field, smp_processor_id())
  32
  33 #define part_stat_read(part, field)                                     \
  34 ({                                                                      \
  35         typeof((part)->dkstats->field) res = 0;                         \
  36         unsigned int _cpu;                                              \
  37         for_each_possible_cpu(_cpu)                                     \
  38                 res += per_cpu_ptr((part)->dkstats, _cpu)->field;       \
  39         res;                                                            \
  40 })
  41
  42 static inline void part_stat_set_all(struct hd_struct *part, int value)
  43 {
  44         int i;
  45
  46         for_each_possible_cpu(i)
  47                 memset(per_cpu_ptr(part->dkstats, i), value,
  48                                 sizeof(struct disk_stats));
  49 }
  50
  51 #define part_stat_read_accum(part, field)                               \
  52         (part_stat_read(part, field[STAT_READ]) +                       \
  53          part_stat_read(part, field[STAT_WRITE]) +                      \
  54          part_stat_read(part, field[STAT_DISCARD]))
  55
  56 #define __part_stat_add(part, field, addnd)                             \
  57         __this_cpu_add((part)->dkstats->field, addnd)
  58
  59 #define part_stat_add(part, field, addnd)       do {                    \
  60         __part_stat_add((part), field, addnd);                          \
  61         if ((part)->partno)                                             \
  62                 __part_stat_add(&part_to_disk((part))->part0,           \
  63                                 field, addnd);                          \
  64 } while (0)
  65
  66 #define part_stat_dec(gendiskp, field)                                  \
  67         part_stat_add(gendiskp, field, -1)
  68 #define part_stat_inc(gendiskp, field)                                  \
  69         part_stat_add(gendiskp, field, 1)
  70 #define part_stat_sub(gendiskp, field, subnd)                           \
  71         part_stat_add(gendiskp, field, -subnd)
  72
  73 #define part_stat_local_dec(gendiskp, field)                            \
  74         local_dec(&(part_stat_get(gendiskp, field)))
  75 #define part_stat_local_inc(gendiskp, field)                            \
  76         local_inc(&(part_stat_get(gendiskp, field)))
  77 #define part_stat_local_read(gendiskp, field)                           \
  78         local_read(&(part_stat_get(gendiskp, field)))
  79 #define part_stat_local_read_cpu(gendiskp, field, cpu)                  \
  80         local_read(&(part_stat_get_cpu(gendiskp, field, cpu)))
  81
  82 #endif /* _LINUX_PART_STAT_H */