diff options
Diffstat (limited to 'kernel/include/linux/delayacct.h')
| -rw-r--r-- | kernel/include/linux/delayacct.h | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/kernel/include/linux/delayacct.h b/kernel/include/linux/delayacct.h new file mode 100644 index 000000000..6cee17c22 --- /dev/null +++ b/kernel/include/linux/delayacct.h @@ -0,0 +1,153 @@ +/* delayacct.h - per-task delay accounting + * + * Copyright (C) Shailabh Nagar, IBM Corp. 2006 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + * + */ + +#ifndef _LINUX_DELAYACCT_H +#define _LINUX_DELAYACCT_H + +#include <linux/sched.h> +#include <linux/slab.h> + +/* + * Per-task flags relevant to delay accounting + * maintained privately to avoid exhausting similar flags in sched.h:PF_* + * Used to set current->delays->flags + */ +#define DELAYACCT_PF_SWAPIN 0x00000001 /* I am doing a swapin */ +#define DELAYACCT_PF_BLKIO 0x00000002 /* I am waiting on IO */ + +#ifdef CONFIG_TASK_DELAY_ACCT + +extern int delayacct_on; /* Delay accounting turned on/off */ +extern struct kmem_cache *delayacct_cache; +extern void delayacct_init(void); +extern void __delayacct_tsk_init(struct task_struct *); +extern void __delayacct_tsk_exit(struct task_struct *); +extern void __delayacct_blkio_start(void); +extern void __delayacct_blkio_end(void); +extern int __delayacct_add_tsk(struct taskstats *, struct task_struct *); +extern __u64 __delayacct_blkio_ticks(struct task_struct *); +extern void __delayacct_freepages_start(void); +extern void __delayacct_freepages_end(void); + +static inline int delayacct_is_task_waiting_on_io(struct task_struct *p) +{ + if (p->delays) + return (p->delays->flags & DELAYACCT_PF_BLKIO); + else + return 0; +} + +static inline void delayacct_set_flag(int flag) +{ + if (current->delays) + current->delays->flags |= flag; +} + +static inline void delayacct_clear_flag(int flag) +{ + if (current->delays) + current->delays->flags &= ~flag; +} + +static inline void delayacct_tsk_init(struct task_struct *tsk) +{ + /* reinitialize in case parent's non-null pointer was dup'ed*/ + tsk->delays = NULL; + if (delayacct_on) + __delayacct_tsk_init(tsk); +} + +/* Free tsk->delays. Called from bad fork and __put_task_struct + * where there's no risk of tsk->delays being accessed elsewhere + */ +static inline void delayacct_tsk_free(struct task_struct *tsk) +{ + if (tsk->delays) + kmem_cache_free(delayacct_cache, tsk->delays); + tsk->delays = NULL; +} + +static inline void delayacct_blkio_start(void) +{ + delayacct_set_flag(DELAYACCT_PF_BLKIO); + if (current->delays) + __delayacct_blkio_start(); +} + +static inline void delayacct_blkio_end(void) +{ + if (current->delays) + __delayacct_blkio_end(); + delayacct_clear_flag(DELAYACCT_PF_BLKIO); +} + +static inline int delayacct_add_tsk(struct taskstats *d, + struct task_struct *tsk) +{ + if (!delayacct_on || !tsk->delays) + return 0; + return __delayacct_add_tsk(d, tsk); +} + +static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk) +{ + if (tsk->delays) + return __delayacct_blkio_ticks(tsk); + return 0; +} + +static inline void delayacct_freepages_start(void) +{ + if (current->delays) + __delayacct_freepages_start(); +} + +static inline void delayacct_freepages_end(void) +{ + if (current->delays) + __delayacct_freepages_end(); +} + +#else +static inline void delayacct_set_flag(int flag) +{} +static inline void delayacct_clear_flag(int flag) +{} +static inline void delayacct_init(void) +{} +static inline void delayacct_tsk_init(struct task_struct *tsk) +{} +static inline void delayacct_tsk_free(struct task_struct *tsk) +{} +static inline void delayacct_blkio_start(void) +{} +static inline void delayacct_blkio_end(void) +{} +static inline int delayacct_add_tsk(struct taskstats *d, + struct task_struct *tsk) +{ return 0; } +static inline __u64 delayacct_blkio_ticks(struct task_struct *tsk) +{ return 0; } +static inline int delayacct_is_task_waiting_on_io(struct task_struct *p) +{ return 0; } +static inline void delayacct_freepages_start(void) +{} +static inline void delayacct_freepages_end(void) +{} + +#endif /* CONFIG_TASK_DELAY_ACCT */ + +#endif |