0ff922452d
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>
94 lines
2.4 KiB
C
94 lines
2.4 KiB
C
/* 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>
|
|
|
|
/*
|
|
* 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 */
|
|
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)
|
|
{
|
|
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 (unlikely(delayacct_on))
|
|
__delayacct_tsk_init(tsk);
|
|
}
|
|
|
|
static inline void delayacct_tsk_exit(struct task_struct *tsk)
|
|
{
|
|
if (tsk->delays)
|
|
__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)
|
|
{}
|
|
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_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
|