summaryrefslogtreecommitdiff
path: root/kernel/tsacct.c
blob: f00de83d02462714526f7c6086e95de172ad9ce5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * tsacct.c - System accounting over taskstats interface
 *
 * Copyright (C) Jay Lan,	<jlan@sgi.com>
 */

#include <linux/kernel.h>
#include <linux/sched/signal.h>
#include <linux/sched/mm.h>
#include <linux/sched/cputime.h>
#include <linux/tsacct_kern.h>
#include <linux/acct.h>
#include <linux/jiffies.h>
#include <linux/mm.h>

/*
 * fill in basic accounting fields
 */
void bacct_add_tsk(struct user_namespace *user_ns,
		   struct pid_namespace *pid_ns,
		   struct taskstats *stats, struct task_struct *tsk)
{
	const struct cred *tcred;
	u64 utime, stime, utimescaled, stimescaled;
	u64 delta;
	time64_t btime;

	BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);

	/* calculate task elapsed time in nsec */
	delta = ktime_get_ns() - tsk->start_time;
	/* Convert to micro seconds */
	do_div(delta, NSEC_PER_USEC);
	stats->ac_etime = delta;
	/* Convert to seconds for btime (note y2106 limit) */
	btime = ktime_get_real_seconds() - div_u64(delta, USEC_PER_SEC);
	stats->ac_btime = clamp_t(time64_t, btime, 0, U32_MAX);
	stats->ac_btime64 = btime;

	if (thread_group_leader(tsk)) {
		stats->ac_exitcode = tsk->exit_code;
		if (tsk->flags & PF_FORKNOEXEC)
			stats->ac_flag |= AFORK;
	}
	if (tsk->flags & PF_SUPERPRIV)
		stats->ac_flag |= ASU;
	if (tsk->flags & PF_DUMPCORE)
		stats->ac_flag |= ACORE;
	if (tsk->flags & PF_SIGNALED)
		stats->ac_flag |= AXSIG;
	stats->ac_nice	 = task_nice(tsk);
	stats->ac_sched	 = tsk->policy;
	stats->ac_pid	 = task_pid_nr_ns(tsk, pid_ns);
	rcu_read_lock();
	tcred = __task_cred(tsk);
	stats->ac_uid	 = from_kuid_munged(user_ns, tcred->uid);
	stats->ac_gid	 = from_kgid_munged(user_ns, tcred->gid);
	stats->ac_ppid	 = pid_alive(tsk) ?
		task_tgid_nr_ns(rcu_dereference(tsk->real_parent), pid_ns) : 0;
	rcu_read_unlock();

	task_cputime(tsk, &utime, &stime);
	stats->ac_utime = div_u64(utime, NSEC_PER_USEC);
	stats->ac_stime = div_u64(stime, NSEC_PER_USEC);

	task_cputime_scaled(tsk, &utimescaled, &stimescaled);
	stats->ac_utimescaled = div_u64(utimescaled, NSEC_PER_USEC);
	stats->ac_stimescaled = div_u64(stimescaled, NSEC_PER_USEC);

	stats->ac_minflt = tsk->min_flt;
	stats->ac_majflt = tsk->maj_flt;

	strncpy(stats->ac_comm, tsk->comm, sizeof(stats->ac_comm));
}


#ifdef CONFIG_TASK_XACCT

#define KB 1024
#define MB (1024*KB)
#define KB_MASK (~(KB-1))
/*
 * fill in extended accounting fields
 */
void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
{
	struct mm_struct *mm;

	/* convert pages-nsec/1024 to Mbyte-usec, see __acct_update_integrals */
	stats->coremem = p->acct_rss_mem1 * PAGE_SIZE;
	do_div(stats->coremem, 1000 * KB);
	stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE;
	do_div(stats->virtmem, 1000 * KB);
	mm = get_task_mm(p);
	if (mm) {
		/* adjust to KB unit */
		stats->hiwater_rss   = get_mm_hiwater_rss(mm) * PAGE_SIZE / KB;
		stats->hiwater_vm    = get_mm_hiwater_vm(mm)  * PAGE_SIZE / KB;
		mmput(mm);
	}
	stats->read_char	= p->ioac.rchar & KB_MASK;
	stats->write_char	= p->ioac.wchar & KB_MASK;
	stats->read_syscalls	= p->ioac.syscr & KB_MASK;
	stats->write_syscalls	= p->ioac.syscw & KB_MASK;
#ifdef CONFIG_TASK_IO_ACCOUNTING
	stats->read_bytes	= p->ioac.read_bytes & KB_MASK;
	stats->write_bytes	= p->ioac.write_bytes & KB_MASK;
	stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes & KB_MASK;
#else
	stats->read_bytes	= 0;
	stats->write_bytes	= 0;
	stats->cancelled_write_bytes = 0;
#endif
}
#undef KB
#undef MB

static void __acct_update_integrals(struct task_struct *tsk,
				    u64 utime, u64 stime)
{
	u64 time, delta;

	if (!likely(tsk->mm))
		return;

	time = stime + utime;
	delta = time - tsk->acct_timexpd;

	if (delta < TICK_NSEC)
		return;

	tsk->acct_timexpd = time;
	/*
	 * Divide by 1024 to avoid overflow, and to avoid division.
	 * The final unit reported to userspace is Mbyte-usecs,
	 * the rest of the math is done in xacct_add_tsk.
	 */
	tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm) >> 10;
	tsk->acct_vm_mem1 += delta * READ_ONCE(tsk->mm->total_vm) >> 10;
}

/**
 * acct_update_integrals - update mm integral fields in task_struct
 * @tsk: task_struct for accounting
 */
void acct_update_integrals(struct task_struct *tsk)
{
	u64 utime, stime;
	unsigned long flags;

	local_irq_save(flags);
	task_cputime(tsk, &utime, &stime);
	__acct_update_integrals(tsk, utime, stime);
	local_irq_restore(flags);
}

/**
 * acct_account_cputime - update mm integral after cputime update
 * @tsk: task_struct for accounting
 */
void acct_account_cputime(struct task_struct *tsk)
{
	__acct_update_integrals(tsk, tsk->utime, tsk->stime);
}

/**
 * acct_clear_integrals - clear the mm integral fields in task_struct
 * @tsk: task_struct whose accounting fields are cleared
 */
void acct_clear_integrals(struct task_struct *tsk)
{
	tsk->acct_timexpd = 0;
	tsk->acct_rss_mem1 = 0;
	tsk->acct_vm_mem1 = 0;
}
#endif