ide-cd: prevent null pointer deref via cdrom_newpc_intr
[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         const struct cred *tcred;
31         struct timespec uptime, ts;
32         u64 ac_etime;
33
34         BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
35
36         /* calculate task elapsed time in timespec */
37         do_posix_clock_monotonic_gettime(&uptime);
38         ts = timespec_sub(uptime, tsk->start_time);
39         /* rebase elapsed time to usec (should never be negative) */
40         ac_etime = timespec_to_ns(&ts);
41         do_div(ac_etime, NSEC_PER_USEC);
42         stats->ac_etime = ac_etime;
43         stats->ac_btime = get_seconds() - ts.tv_sec;
44         if (thread_group_leader(tsk)) {
45                 stats->ac_exitcode = tsk->exit_code;
46                 if (tsk->flags & PF_FORKNOEXEC)
47                         stats->ac_flag |= AFORK;
48         }
49         if (tsk->flags & PF_SUPERPRIV)
50                 stats->ac_flag |= ASU;
51         if (tsk->flags & PF_DUMPCORE)
52                 stats->ac_flag |= ACORE;
53         if (tsk->flags & PF_SIGNALED)
54                 stats->ac_flag |= AXSIG;
55         stats->ac_nice   = task_nice(tsk);
56         stats->ac_sched  = tsk->policy;
57         stats->ac_pid    = tsk->pid;
58         rcu_read_lock();
59         tcred = __task_cred(tsk);
60         stats->ac_uid    = tcred->uid;
61         stats->ac_gid    = tcred->gid;
62         stats->ac_ppid   = pid_alive(tsk) ?
63                                 rcu_dereference(tsk->real_parent)->tgid : 0;
64         rcu_read_unlock();
65         stats->ac_utime  = cputime_to_msecs(tsk->utime) * USEC_PER_MSEC;
66         stats->ac_stime  = cputime_to_msecs(tsk->stime) * USEC_PER_MSEC;
67         stats->ac_utimescaled =
68                 cputime_to_msecs(tsk->utimescaled) * USEC_PER_MSEC;
69         stats->ac_stimescaled =
70                 cputime_to_msecs(tsk->stimescaled) * USEC_PER_MSEC;
71         stats->ac_minflt = tsk->min_flt;
72         stats->ac_majflt = tsk->maj_flt;
73
74         strncpy(stats->ac_comm, tsk->comm, sizeof(stats->ac_comm));
75 }
76
77
78 #ifdef CONFIG_TASK_XACCT
79
80 #define KB 1024
81 #define MB (1024*KB)
82 /*
83  * fill in extended accounting fields
84  */
85 void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
86 {
87         struct mm_struct *mm;
88
89         /* convert pages-usec to Mbyte-usec */
90         stats->coremem = p->acct_rss_mem1 * PAGE_SIZE / MB;
91         stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE / MB;
92         mm = get_task_mm(p);
93         if (mm) {
94                 /* adjust to KB unit */
95                 stats->hiwater_rss   = get_mm_hiwater_rss(mm) * PAGE_SIZE / KB;
96                 stats->hiwater_vm    = get_mm_hiwater_vm(mm)  * PAGE_SIZE / KB;
97                 mmput(mm);
98         }
99         stats->read_char        = p->ioac.rchar;
100         stats->write_char       = p->ioac.wchar;
101         stats->read_syscalls    = p->ioac.syscr;
102         stats->write_syscalls   = p->ioac.syscw;
103 #ifdef CONFIG_TASK_IO_ACCOUNTING
104         stats->read_bytes       = p->ioac.read_bytes;
105         stats->write_bytes      = p->ioac.write_bytes;
106         stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes;
107 #else
108         stats->read_bytes       = 0;
109         stats->write_bytes      = 0;
110         stats->cancelled_write_bytes = 0;
111 #endif
112 }
113 #undef KB
114 #undef MB
115
116 /**
117  * acct_update_integrals - update mm integral fields in task_struct
118  * @tsk: task_struct for accounting
119  */
120 void acct_update_integrals(struct task_struct *tsk)
121 {
122         if (likely(tsk->mm)) {
123                 cputime_t time, dtime;
124                 struct timeval value;
125                 unsigned long flags;
126                 u64 delta;
127
128                 local_irq_save(flags);
129                 time = tsk->stime + tsk->utime;
130                 dtime = cputime_sub(time, tsk->acct_timexpd);
131                 jiffies_to_timeval(cputime_to_jiffies(dtime), &value);
132                 delta = value.tv_sec;
133                 delta = delta * USEC_PER_SEC + value.tv_usec;
134
135                 if (delta == 0)
136                         goto out;
137                 tsk->acct_timexpd = time;
138                 tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm);
139                 tsk->acct_vm_mem1 += delta * tsk->mm->total_vm;
140         out:
141                 local_irq_restore(flags);
142         }
143 }
144
145 /**
146  * acct_clear_integrals - clear the mm integral fields in task_struct
147  * @tsk: task_struct whose accounting fields are cleared
148  */
149 void acct_clear_integrals(struct task_struct *tsk)
150 {
151         tsk->acct_timexpd = 0;
152         tsk->acct_rss_mem1 = 0;
153         tsk->acct_vm_mem1 = 0;
154 }
155 #endif