block/mq-deadline-cgroup.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #if !defined(_MQ_DEADLINE_CGROUP_H_)
   4 #define _MQ_DEADLINE_CGROUP_H_
   5
   6 #include <linux/blk-cgroup.h>
   7
   8 struct request_queue;
   9
  10 /**
  11  * struct io_stats_per_prio - I/O statistics per I/O priority class.
  12  * @inserted: Number of inserted requests.
  13  * @merged: Number of merged requests.
  14  * @dispatched: Number of dispatched requests.
  15  * @completed: Number of I/O completions.
  16  */
  17 struct io_stats_per_prio {
  18         local_t inserted;
  19         local_t merged;
  20         local_t dispatched;
  21         local_t completed;
  22 };
  23
  24 /* I/O statistics per I/O cgroup per I/O priority class (IOPRIO_CLASS_*). */
  25 struct blkcg_io_stats {
  26         struct io_stats_per_prio stats[4];
  27 };
  28
  29 /**
  30  * struct dd_blkcg - Per cgroup data.
  31  * @cpd: blkcg_policy_data structure.
  32  * @stats: I/O statistics.
  33  */
  34 struct dd_blkcg {
  35         struct blkcg_policy_data cpd;   /* must be the first member */
  36         struct blkcg_io_stats __percpu *stats;
  37 };
  38
  39 /*
  40  * Count one event of type 'event_type' and with I/O priority class
  41  * 'prio_class'.
  42  */
  43 #define ddcg_count(ddcg, event_type, prio_class) do {                   \
  44 if (ddcg) {                                                             \
  45         struct blkcg_io_stats *io_stats = get_cpu_ptr((ddcg)->stats);   \
  46                                                                         \
  47         BUILD_BUG_ON(!__same_type((ddcg), struct dd_blkcg *));          \
  48         BUILD_BUG_ON(!__same_type((prio_class), u8));                   \
  49         local_inc(&io_stats->stats[(prio_class)].event_type);           \
  50         put_cpu_ptr(io_stats);                                          \
  51 }                                                                       \
  52 } while (0)
  53
  54 /*
  55  * Returns the total number of ddcg_count(ddcg, event_type, prio_class) calls
  56  * across all CPUs. No locking or barriers since it is fine if the returned
  57  * sum is slightly outdated.
  58  */
  59 #define ddcg_sum(ddcg, event_type, prio) ({                             \
  60         unsigned int cpu;                                               \
  61         u32 sum = 0;                                                    \
  62                                                                         \
  63         BUILD_BUG_ON(!__same_type((ddcg), struct dd_blkcg *));          \
  64         BUILD_BUG_ON(!__same_type((prio), u8));                         \
  65         for_each_present_cpu(cpu)                                       \
  66                 sum += local_read(&per_cpu_ptr((ddcg)->stats, cpu)->    \
  67                                   stats[(prio)].event_type);            \
  68         sum;                                                            \
  69 })
  70
  71 #ifdef CONFIG_BLK_CGROUP
  72
  73 /**
  74  * struct dd_blkg - Per (cgroup, request queue) data.
  75  * @pd: blkg_policy_data structure.
  76  */
  77 struct dd_blkg {
  78         struct blkg_policy_data pd;     /* must be the first member */
  79 };
  80
  81 struct dd_blkcg *dd_blkcg_from_bio(struct bio *bio);
  82 int dd_activate_policy(struct request_queue *q);
  83 void dd_deactivate_policy(struct request_queue *q);
  84 int __init dd_blkcg_init(void);
  85 void __exit dd_blkcg_exit(void);
  86
  87 #else /* CONFIG_BLK_CGROUP */
  88
  89 static inline struct dd_blkcg *dd_blkcg_from_bio(struct bio *bio)
  90 {
  91         return NULL;
  92 }
  93
  94 static inline int dd_activate_policy(struct request_queue *q)
  95 {
  96         return 0;
  97 }
  98
  99 static inline void dd_deactivate_policy(struct request_queue *q)
 100 {
 101 }
 102
 103 static inline int dd_blkcg_init(void)
 104 {
 105         return 0;
 106 }
 107
 108 static inline void dd_blkcg_exit(void)
 109 {
 110 }
 111
 112 #endif /* CONFIG_BLK_CGROUP */
 113
 114 #endif /* _MQ_DEADLINE_CGROUP_H_ */