sched: domain sysctl fixes: do not crash on allocation failure
[linux-2.6] / kernel / tsacct.c
1 /*
2  * tsacct.c - System accounting over taskstats interface
3  *
4  * Copyright (C) Jay Lan,       <jlan@sgi.com>
5  *
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  */
18
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
21 #include <linux/tsacct_kern.h>
22 #include <linux/acct.h>
23 #include <linux/jiffies.h>
24
25 /*
26  * fill in basic accounting fields
27  */
28 void bacct_add_tsk(struct taskstats *stats, struct task_struct *tsk)
29 {
30         struct timespec uptime, ts;
31         s64 ac_etime;
32
33         BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
34
35         /* calculate task elapsed time in timespec */
36         do_posix_clock_monotonic_gettime(&uptime);
37         ts = timespec_sub(uptime, tsk->start_time);
38         /* rebase elapsed time to usec */
39         ac_etime = timespec_to_ns(&ts);
40         do_div(ac_etime, NSEC_PER_USEC);
41         stats->ac_etime = ac_etime;
42         stats->ac_btime = get_seconds() - ts.tv_sec;
43         if (thread_group_leader(tsk)) {
44                 stats->ac_exitcode = tsk->exit_code;
45                 if (tsk->flags & PF_FORKNOEXEC)
46                         stats->ac_flag |= AFORK;
47         }
48         if (tsk->flags & PF_SUPERPRIV)
49                 stats->ac_flag |= ASU;
50         if (tsk->flags & PF_DUMPCORE)
51                 stats->ac_flag |= ACORE;
52         if (tsk->flags & PF_SIGNALED)
53                 stats->ac_flag |= AXSIG;
54         stats->ac_nice   = task_nice(tsk);
55         stats->ac_sched  = tsk->policy;
56         stats->ac_uid    = tsk->uid;
57         stats->ac_gid    = tsk->gid;
58         stats->ac_pid    = tsk->pid;
59         rcu_read_lock();
60         stats->ac_ppid   = pid_alive(tsk) ?
61                                 rcu_dereference(tsk->real_parent)->tgid : 0;
62         rcu_read_unlock();
63         stats->ac_utime  = cputime_to_msecs(tsk->utime) * USEC_PER_MSEC;
64         stats->ac_stime  = cputime_to_msecs(tsk->stime) * USEC_PER_MSEC;
65         stats->ac_minflt = tsk->min_flt;
66         stats->ac_majflt = tsk->maj_flt;
67
68         strncpy(stats->ac_comm, tsk->comm, sizeof(stats->ac_comm));
69 }
70
71
72 #ifdef CONFIG_TASK_XACCT
73
74 #define KB 1024
75 #define MB (1024*KB)
76 /*
77  * fill in extended accounting fields
78  */
79 void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
80 {
81         struct mm_struct *mm;
82
83         /* convert pages-jiffies to Mbyte-usec */
84         stats->coremem = jiffies_to_usecs(p->acct_rss_mem1) * PAGE_SIZE / MB;
85         stats->virtmem = jiffies_to_usecs(p->acct_vm_mem1) * PAGE_SIZE / MB;
86         mm = get_task_mm(p);
87         if (mm) {
88                 /* adjust to KB unit */
89                 stats->hiwater_rss   = mm->hiwater_rss * PAGE_SIZE / KB;
90                 stats->hiwater_vm    = mm->hiwater_vm * PAGE_SIZE / KB;
91                 mmput(mm);
92         }
93         stats->read_char        = p->rchar;
94         stats->write_char       = p->wchar;
95         stats->read_syscalls    = p->syscr;
96         stats->write_syscalls   = p->syscw;
97 #ifdef CONFIG_TASK_IO_ACCOUNTING
98         stats->read_bytes       = p->ioac.read_bytes;
99         stats->write_bytes      = p->ioac.write_bytes;
100         stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes;
101 #else
102         stats->read_bytes       = 0;
103         stats->write_bytes      = 0;
104         stats->cancelled_write_bytes = 0;
105 #endif
106 }
107 #undef KB
108 #undef MB
109
110 /**
111  * acct_update_integrals - update mm integral fields in task_struct
112  * @tsk: task_struct for accounting
113  */
114 void acct_update_integrals(struct task_struct *tsk)
115 {
116         if (likely(tsk->mm)) {
117                 long delta = cputime_to_jiffies(
118                         cputime_sub(tsk->stime, tsk->acct_stimexpd));
119
120                 if (delta == 0)
121                         return;
122                 tsk->acct_stimexpd = tsk->stime;
123                 tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm);
124                 tsk->acct_vm_mem1 += delta * tsk->mm->total_vm;
125         }
126 }
127
128 /**
129  * acct_clear_integrals - clear the mm integral fields in task_struct
130  * @tsk: task_struct whose accounting fields are cleared
131  */
132 void acct_clear_integrals(struct task_struct *tsk)
133 {
134         tsk->acct_stimexpd = 0;
135         tsk->acct_rss_mem1 = 0;
136         tsk->acct_vm_mem1 = 0;
137 }
138 #endif