1 /* delayacct.h - per-task delay accounting 2 * 3 * Copyright (C) Shailabh Nagar, IBM Corp. 2006 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 13 * the GNU General Public License for more details. 14 * 15 */ 16 17 #ifndef _LINUX_DELAYACCT_H 18 #define _LINUX_DELAYACCT_H 19 20 #include <linux/sched.h> 21 #include <linux/taskstats_kern.h> 22 23 /* 24 * Per-task flags relevant to delay accounting 25 * maintained privately to avoid exhausting similar flags in sched.h:PF_* 26 * Used to set current->delays->flags 27 */ 28 #define DELAYACCT_PF_SWAPIN 0x00000001 /* I am doing a swapin */ 29 30 #ifdef CONFIG_TASK_DELAY_ACCT 31 32 extern int delayacct_on; /* Delay accounting turned on/off */ 33 extern struct kmem_cache *delayacct_cache; 34 extern void delayacct_init(void); 35 extern void __delayacct_tsk_init(struct task_struct *); 36 extern void __delayacct_tsk_exit(struct task_struct *); 37 extern void __delayacct_blkio_start(void); 38 extern void __delayacct_blkio_end(void); 39 extern int __delayacct_add_tsk(struct taskstats *, struct task_struct *); 40 extern __u64 __delayacct_blkio_ticks(struct task_struct *); 41 42 static inline void delayacct_set_flag(int flag) 43 { 44 if (current->delays) 45 current->delays->flags |= flag; 46 } 47 48 static inline void delayacct_clear_flag(int flag) 49 { 50 if (current->delays) 51 current->delays->flags &= ~flag; 52 } 53 54 static inline void delayacct_tsk_init(struct task_struct *tsk) 55 { 56 /* reinitialize in case parent's non-null pointer was dup'ed*/ 57 tsk->delays = NULL; 58 if (delayacct_on) 59 __delayacct_tsk_init(tsk); 60 } 61 62 /* Free tsk->delays. Called from bad fork and __put_task_struct 63 * where there's no risk of tsk->delays being accessed elsewhere 64 */ 65 static inline void delayacct_tsk_free(struct task_struct *tsk) 66 { 67 if (tsk->delays) 68 kmem_cache_free(delayacct_cache, tsk->delays); 69 tsk->delays = NULL; 70 } 71 72 static inline void delayacct_blkio_start(void) 73 { 74 if (current->delays) 75 __delayacct_blkio_start(); 76 } 77 78 static inline void delayacct_blkio_end(void) 79 { 80 if (current->delays) 81 __delayacct_blkio_end(); 82 } 83 84 static inline int delayacct_add_tsk(struct taskstats *d, 85 struct task_struct *tsk) 86 { 87 if (!delayacct_on || !tsk->delays) 88 return 0; 89 return __delayacct_add_tsk(d, tsk); 90 } 91 92 static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk) 93 { 94 if (tsk->delays) 95 return __delayacct_blkio_ticks(tsk); 96 return 0; 97 } 98 99 #else 100 static inline void delayacct_set_flag(int flag) 101 {} 102 static inline void delayacct_clear_flag(int flag) 103 {} 104 static inline void delayacct_init(void) 105 {} 106 static inline void delayacct_tsk_init(struct task_struct *tsk) 107 {} 108 static inline void delayacct_tsk_free(struct task_struct *tsk) 109 {} 110 static inline void delayacct_blkio_start(void) 111 {} 112 static inline void delayacct_blkio_end(void) 113 {} 114 static inline int delayacct_add_tsk(struct taskstats *d, 115 struct task_struct *tsk) 116 { return 0; } 117 static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk) 118 { return 0; } 119 #endif /* CONFIG_TASK_DELAY_ACCT */ 120 121 #endif 122