1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* delayacct.h - per-task delay accounting 3 * 4 * Copyright (C) Shailabh Nagar, IBM Corp. 2006 5 */ 6 7 #ifndef _LINUX_DELAYACCT_H 8 #define _LINUX_DELAYACCT_H 9 10 #include <uapi/linux/taskstats.h> 11 12 #ifdef CONFIG_TASK_DELAY_ACCT 13 struct task_delay_info { 14 raw_spinlock_t lock; 15 16 /* For each stat XXX, add following, aligned appropriately 17 * 18 * struct timespec XXX_start, XXX_end; 19 * u64 XXX_delay; 20 * u32 XXX_count; 21 * 22 * Atomicity of updates to XXX_delay, XXX_count protected by 23 * single lock above (split into XXX_lock if contention is an issue). 24 */ 25 26 /* 27 * XXX_count is incremented on every XXX operation, the delay 28 * associated with the operation is added to XXX_delay. 29 * XXX_delay contains the accumulated delay time in nanoseconds. 30 */ 31 u64 blkio_start; 32 u64 blkio_delay; /* wait for sync block io completion */ 33 u64 swapin_start; 34 u64 swapin_delay; /* wait for swapin */ 35 u32 blkio_count; /* total count of the number of sync block */ 36 /* io operations performed */ 37 u32 swapin_count; /* total count of swapin */ 38 39 u64 freepages_start; 40 u64 freepages_delay; /* wait for memory reclaim */ 41 42 u64 thrashing_start; 43 u64 thrashing_delay; /* wait for thrashing page */ 44 45 u32 freepages_count; /* total count of memory reclaim */ 46 u32 thrashing_count; /* total count of thrash waits */ 47 }; 48 #endif 49 50 #include <linux/sched.h> 51 #include <linux/slab.h> 52 #include <linux/jump_label.h> 53 54 #ifdef CONFIG_TASK_DELAY_ACCT 55 DECLARE_STATIC_KEY_FALSE(delayacct_key); 56 extern int delayacct_on; /* Delay accounting turned on/off */ 57 extern struct kmem_cache *delayacct_cache; 58 extern void delayacct_init(void); 59 60 extern int sysctl_delayacct(struct ctl_table *table, int write, void *buffer, 61 size_t *lenp, loff_t *ppos); 62 63 extern void __delayacct_tsk_init(struct task_struct *); 64 extern void __delayacct_tsk_exit(struct task_struct *); 65 extern void __delayacct_blkio_start(void); 66 extern void __delayacct_blkio_end(struct task_struct *); 67 extern int delayacct_add_tsk(struct taskstats *, struct task_struct *); 68 extern __u64 __delayacct_blkio_ticks(struct task_struct *); 69 extern void __delayacct_freepages_start(void); 70 extern void __delayacct_freepages_end(void); 71 extern void __delayacct_thrashing_start(void); 72 extern void __delayacct_thrashing_end(void); 73 extern void __delayacct_swapin_start(void); 74 extern void __delayacct_swapin_end(void); 75 76 static inline void delayacct_tsk_init(struct task_struct *tsk) 77 { 78 /* reinitialize in case parent's non-null pointer was dup'ed*/ 79 tsk->delays = NULL; 80 if (delayacct_on) 81 __delayacct_tsk_init(tsk); 82 } 83 84 /* Free tsk->delays. Called from bad fork and __put_task_struct 85 * where there's no risk of tsk->delays being accessed elsewhere 86 */ 87 static inline void delayacct_tsk_free(struct task_struct *tsk) 88 { 89 if (tsk->delays) 90 kmem_cache_free(delayacct_cache, tsk->delays); 91 tsk->delays = NULL; 92 } 93 94 static inline void delayacct_blkio_start(void) 95 { 96 if (!static_branch_unlikely(&delayacct_key)) 97 return; 98 99 if (current->delays) 100 __delayacct_blkio_start(); 101 } 102 103 static inline void delayacct_blkio_end(struct task_struct *p) 104 { 105 if (!static_branch_unlikely(&delayacct_key)) 106 return; 107 108 if (p->delays) 109 __delayacct_blkio_end(p); 110 } 111 112 static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk) 113 { 114 if (tsk->delays) 115 return __delayacct_blkio_ticks(tsk); 116 return 0; 117 } 118 119 static inline void delayacct_freepages_start(void) 120 { 121 if (!static_branch_unlikely(&delayacct_key)) 122 return; 123 124 if (current->delays) 125 __delayacct_freepages_start(); 126 } 127 128 static inline void delayacct_freepages_end(void) 129 { 130 if (!static_branch_unlikely(&delayacct_key)) 131 return; 132 133 if (current->delays) 134 __delayacct_freepages_end(); 135 } 136 137 static inline void delayacct_thrashing_start(void) 138 { 139 if (!static_branch_unlikely(&delayacct_key)) 140 return; 141 142 if (current->delays) 143 __delayacct_thrashing_start(); 144 } 145 146 static inline void delayacct_thrashing_end(void) 147 { 148 if (!static_branch_unlikely(&delayacct_key)) 149 return; 150 151 if (current->delays) 152 __delayacct_thrashing_end(); 153 } 154 155 static inline void delayacct_swapin_start(void) 156 { 157 if (!static_branch_unlikely(&delayacct_key)) 158 return; 159 160 if (current->delays) 161 __delayacct_swapin_start(); 162 } 163 164 static inline void delayacct_swapin_end(void) 165 { 166 if (!static_branch_unlikely(&delayacct_key)) 167 return; 168 169 if (current->delays) 170 __delayacct_swapin_end(); 171 } 172 173 #else 174 static inline void delayacct_init(void) 175 {} 176 static inline void delayacct_tsk_init(struct task_struct *tsk) 177 {} 178 static inline void delayacct_tsk_free(struct task_struct *tsk) 179 {} 180 static inline void delayacct_blkio_start(void) 181 {} 182 static inline void delayacct_blkio_end(struct task_struct *p) 183 {} 184 static inline int delayacct_add_tsk(struct taskstats *d, 185 struct task_struct *tsk) 186 { return 0; } 187 static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk) 188 { return 0; } 189 static inline int delayacct_is_task_waiting_on_io(struct task_struct *p) 190 { return 0; } 191 static inline void delayacct_freepages_start(void) 192 {} 193 static inline void delayacct_freepages_end(void) 194 {} 195 static inline void delayacct_thrashing_start(void) 196 {} 197 static inline void delayacct_thrashing_end(void) 198 {} 199 static inline void delayacct_swapin_start(void) 200 {} 201 static inline void delayacct_swapin_end(void) 202 {} 203 204 #endif /* CONFIG_TASK_DELAY_ACCT */ 205 206 #endif 207