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| author | Shailabh Nagar <nagar@watson.ibm.com> | 2006-07-14 00:24:37 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-07-14 21:53:56 -0700 |
| commit | 0ff922452df86f3e9a2c6f705c4588ec62d096a7 (patch) | |
| tree | ac84041bfb63f12d0e2db733c46b2cd2438b4882 /include/linux | |
| parent | ca74e92b4698276b6696f15a801759f50944f387 (diff) | |
| download | lwn-0ff922452df86f3e9a2c6f705c4588ec62d096a7.tar.gz lwn-0ff922452df86f3e9a2c6f705c4588ec62d096a7.zip | |
[PATCH] per-task-delay-accounting: sync block I/O and swapin delay collection
Unlike earlier iterations of the delay accounting patches, now delays are only
collected for the actual I/O waits rather than try and cover the delays seen
in I/O submission paths.
Account separately for block I/O delays incurred as a result of swapin page
faults whose frequency can be affected by the task/process' rss limit. Hence
swapin delays can act as feedback for rss limit changes independent of I/O
priority changes.
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/delayacct.h | 25 | ||||
| -rw-r--r-- | include/linux/sched.h | 13 |
2 files changed, 38 insertions, 0 deletions
diff --git a/include/linux/delayacct.h b/include/linux/delayacct.h index 9572cfa1f129..0ecbf9aad8e1 100644 --- a/include/linux/delayacct.h +++ b/include/linux/delayacct.h @@ -19,6 +19,13 @@ #include <linux/sched.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 */ + #ifdef CONFIG_TASK_DELAY_ACCT extern int delayacct_on; /* Delay accounting turned on/off */ @@ -26,6 +33,8 @@ extern kmem_cache_t *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); static inline void delayacct_set_flag(int flag) { @@ -53,6 +62,18 @@ static inline void delayacct_tsk_exit(struct task_struct *tsk) __delayacct_tsk_exit(tsk); } +static inline void delayacct_blkio_start(void) +{ + if (current->delays) + __delayacct_blkio_start(); +} + +static inline void delayacct_blkio_end(void) +{ + if (current->delays) + __delayacct_blkio_end(); +} + #else static inline void delayacct_set_flag(int flag) {} @@ -64,6 +85,10 @@ static inline void delayacct_tsk_init(struct task_struct *tsk) {} static inline void delayacct_tsk_exit(struct task_struct *tsk) {} +static inline void delayacct_blkio_start(void) +{} +static inline void delayacct_blkio_end(void) +{} #endif /* CONFIG_TASK_DELAY_ACCT */ #endif diff --git a/include/linux/sched.h b/include/linux/sched.h index 7a54e62763c5..2f43f1fb7de7 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -566,6 +566,19 @@ struct task_delay_info { * Atomicity of updates to XXX_delay, XXX_count protected by * single lock above (split into XXX_lock if contention is an issue). */ + + /* + * XXX_count is incremented on every XXX operation, the delay + * associated with the operation is added to XXX_delay. + * XXX_delay contains the accumulated delay time in nanoseconds. + */ + struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */ + u64 blkio_delay; /* wait for sync block io completion */ + u64 swapin_delay; /* wait for swapin block io completion */ + u32 blkio_count; /* total count of the number of sync block */ + /* io operations performed */ + u32 swapin_count; /* total count of the number of swapin block */ + /* io operations performed */ }; #endif |