]>
Commit | Line | Data |
---|---|---|
ca74e92b SN |
1 | /* delayacct.c - 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 would be useful, but | |
11 | * 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 | #include <linux/sched.h> | |
17 | #include <linux/slab.h> | |
6952b61d | 18 | #include <linux/taskstats.h> |
ca74e92b SN |
19 | #include <linux/time.h> |
20 | #include <linux/sysctl.h> | |
21 | #include <linux/delayacct.h> | |
c9aaa895 | 22 | #include <linux/module.h> |
ca74e92b | 23 | |
163ecdff | 24 | int delayacct_on __read_mostly = 1; /* Delay accounting turned on/off */ |
c9aaa895 | 25 | EXPORT_SYMBOL_GPL(delayacct_on); |
e18b890b | 26 | struct kmem_cache *delayacct_cache; |
ca74e92b | 27 | |
163ecdff | 28 | static int __init delayacct_setup_disable(char *str) |
ca74e92b | 29 | { |
163ecdff | 30 | delayacct_on = 0; |
ca74e92b SN |
31 | return 1; |
32 | } | |
163ecdff | 33 | __setup("nodelayacct", delayacct_setup_disable); |
ca74e92b SN |
34 | |
35 | void delayacct_init(void) | |
36 | { | |
0a31bd5f | 37 | delayacct_cache = KMEM_CACHE(task_delay_info, SLAB_PANIC); |
ca74e92b SN |
38 | delayacct_tsk_init(&init_task); |
39 | } | |
40 | ||
41 | void __delayacct_tsk_init(struct task_struct *tsk) | |
42 | { | |
e94b1766 | 43 | tsk->delays = kmem_cache_zalloc(delayacct_cache, GFP_KERNEL); |
ca74e92b SN |
44 | if (tsk->delays) |
45 | spin_lock_init(&tsk->delays->lock); | |
46 | } | |
47 | ||
ca74e92b SN |
48 | /* |
49 | * Finish delay accounting for a statistic using | |
50 | * its timestamps (@start, @end), accumalator (@total) and @count | |
51 | */ | |
52 | ||
53 | static void delayacct_end(struct timespec *start, struct timespec *end, | |
54 | u64 *total, u32 *count) | |
55 | { | |
56 | struct timespec ts; | |
57 | s64 ns; | |
64efade1 | 58 | unsigned long flags; |
ca74e92b | 59 | |
b5d76825 | 60 | ktime_get_ts(end); |
ca74e92b SN |
61 | ts = timespec_sub(*end, *start); |
62 | ns = timespec_to_ns(&ts); | |
63 | if (ns < 0) | |
64 | return; | |
65 | ||
64efade1 | 66 | spin_lock_irqsave(¤t->delays->lock, flags); |
ca74e92b SN |
67 | *total += ns; |
68 | (*count)++; | |
64efade1 | 69 | spin_unlock_irqrestore(¤t->delays->lock, flags); |
ca74e92b SN |
70 | } |
71 | ||
0ff92245 SN |
72 | void __delayacct_blkio_start(void) |
73 | { | |
b5d76825 | 74 | ktime_get_ts(¤t->delays->blkio_start); |
0ff92245 SN |
75 | } |
76 | ||
77 | void __delayacct_blkio_end(void) | |
78 | { | |
79 | if (current->delays->flags & DELAYACCT_PF_SWAPIN) | |
80 | /* Swapin block I/O */ | |
81 | delayacct_end(¤t->delays->blkio_start, | |
82 | ¤t->delays->blkio_end, | |
83 | ¤t->delays->swapin_delay, | |
84 | ¤t->delays->swapin_count); | |
85 | else /* Other block I/O */ | |
86 | delayacct_end(¤t->delays->blkio_start, | |
87 | ¤t->delays->blkio_end, | |
88 | ¤t->delays->blkio_delay, | |
89 | ¤t->delays->blkio_count); | |
90 | } | |
6f44993f SN |
91 | |
92 | int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk) | |
93 | { | |
94 | s64 tmp; | |
172ba844 BS |
95 | unsigned long t1; |
96 | unsigned long long t2, t3; | |
64efade1 | 97 | unsigned long flags; |
172ba844 | 98 | struct timespec ts; |
6fac4829 | 99 | cputime_t utime, stime, stimescaled, utimescaled; |
6f44993f | 100 | |
6f44993f | 101 | tmp = (s64)d->cpu_run_real_total; |
6fac4829 FW |
102 | task_cputime(tsk, &utime, &stime); |
103 | cputime_to_timespec(utime + stime, &ts); | |
6f44993f SN |
104 | tmp += timespec_to_ns(&ts); |
105 | d->cpu_run_real_total = (tmp < (s64)d->cpu_run_real_total) ? 0 : tmp; | |
106 | ||
c66f08be | 107 | tmp = (s64)d->cpu_scaled_run_real_total; |
6fac4829 FW |
108 | task_cputime_scaled(tsk, &utimescaled, &stimescaled); |
109 | cputime_to_timespec(utimescaled + stimescaled, &ts); | |
c66f08be MN |
110 | tmp += timespec_to_ns(&ts); |
111 | d->cpu_scaled_run_real_total = | |
112 | (tmp < (s64)d->cpu_scaled_run_real_total) ? 0 : tmp; | |
113 | ||
6f44993f SN |
114 | /* |
115 | * No locking available for sched_info (and too expensive to add one) | |
116 | * Mitigate by taking snapshot of values | |
117 | */ | |
2d72376b | 118 | t1 = tsk->sched_info.pcount; |
6f44993f | 119 | t2 = tsk->sched_info.run_delay; |
9c2c4802 | 120 | t3 = tsk->se.sum_exec_runtime; |
6f44993f SN |
121 | |
122 | d->cpu_count += t1; | |
123 | ||
172ba844 | 124 | tmp = (s64)d->cpu_delay_total + t2; |
6f44993f SN |
125 | d->cpu_delay_total = (tmp < (s64)d->cpu_delay_total) ? 0 : tmp; |
126 | ||
172ba844 | 127 | tmp = (s64)d->cpu_run_virtual_total + t3; |
6f44993f SN |
128 | d->cpu_run_virtual_total = |
129 | (tmp < (s64)d->cpu_run_virtual_total) ? 0 : tmp; | |
130 | ||
131 | /* zero XXX_total, non-zero XXX_count implies XXX stat overflowed */ | |
132 | ||
64efade1 | 133 | spin_lock_irqsave(&tsk->delays->lock, flags); |
6f44993f SN |
134 | tmp = d->blkio_delay_total + tsk->delays->blkio_delay; |
135 | d->blkio_delay_total = (tmp < d->blkio_delay_total) ? 0 : tmp; | |
136 | tmp = d->swapin_delay_total + tsk->delays->swapin_delay; | |
137 | d->swapin_delay_total = (tmp < d->swapin_delay_total) ? 0 : tmp; | |
016ae219 KK |
138 | tmp = d->freepages_delay_total + tsk->delays->freepages_delay; |
139 | d->freepages_delay_total = (tmp < d->freepages_delay_total) ? 0 : tmp; | |
6f44993f SN |
140 | d->blkio_count += tsk->delays->blkio_count; |
141 | d->swapin_count += tsk->delays->swapin_count; | |
016ae219 | 142 | d->freepages_count += tsk->delays->freepages_count; |
64efade1 | 143 | spin_unlock_irqrestore(&tsk->delays->lock, flags); |
6f44993f | 144 | |
6f44993f SN |
145 | return 0; |
146 | } | |
25890454 SN |
147 | |
148 | __u64 __delayacct_blkio_ticks(struct task_struct *tsk) | |
149 | { | |
150 | __u64 ret; | |
64efade1 | 151 | unsigned long flags; |
25890454 | 152 | |
64efade1 | 153 | spin_lock_irqsave(&tsk->delays->lock, flags); |
25890454 SN |
154 | ret = nsec_to_clock_t(tsk->delays->blkio_delay + |
155 | tsk->delays->swapin_delay); | |
64efade1 | 156 | spin_unlock_irqrestore(&tsk->delays->lock, flags); |
25890454 SN |
157 | return ret; |
158 | } | |
159 | ||
873b4771 KK |
160 | void __delayacct_freepages_start(void) |
161 | { | |
b5d76825 | 162 | ktime_get_ts(¤t->delays->freepages_start); |
873b4771 KK |
163 | } |
164 | ||
165 | void __delayacct_freepages_end(void) | |
166 | { | |
167 | delayacct_end(¤t->delays->freepages_start, | |
168 | ¤t->delays->freepages_end, | |
169 | ¤t->delays->freepages_delay, | |
170 | ¤t->delays->freepages_count); | |
171 | } | |
172 |