projects/linux·blob master · refs

181 lines · 4.9 KiB

1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * tsacct.c - System accounting over taskstats interface
4 *
5 * Copyright (C) Jay Lan, <[email protected]>
6 */
7
8#include <linux/kernel.h>
9#include <linux/sched/signal.h>
10#include <linux/sched/mm.h>
11#include <linux/sched/cputime.h>
12#include <linux/tsacct_kern.h>
13#include <linux/acct.h>
14#include <linux/jiffies.h>
15#include <linux/mm.h>
16
17/*
18 * fill in basic accounting fields
19 */
20void bacct_add_tsk(struct user_namespace *user_ns,
21 struct pid_namespace *pid_ns,
22 struct taskstats *stats, struct task_struct *tsk)
23{
24 const struct cred *tcred;
25 u64 utime, stime, utimescaled, stimescaled;
26 u64 now_ns, delta;
27 time64_t btime;
28
29 BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
30
31 /* calculate task elapsed time in nsec */
32 now_ns = ktime_get_ns();
33 /* store whole group time first */
34 delta = now_ns - tsk->group_leader->start_time;
35 /* Convert to micro seconds */
36 do_div(delta, NSEC_PER_USEC);
37 stats->ac_tgetime = delta;
38 delta = now_ns - tsk->start_time;
39 do_div(delta, NSEC_PER_USEC);
40 stats->ac_etime = delta;
41 /* Convert to seconds for btime (note y2106 limit) */
42 btime = ktime_get_real_seconds() - div_u64(delta, USEC_PER_SEC);
43 stats->ac_btime = clamp_t(time64_t, btime, 0, U32_MAX);
44 stats->ac_btime64 = btime;
45
46 if (tsk->flags & PF_EXITING)
47 stats->ac_exitcode = tsk->exit_code;
48 if (thread_group_leader(tsk) && (tsk->flags & PF_FORKNOEXEC))
49 stats->ac_flag |= AFORK;
50 if (tsk->flags & PF_SUPERPRIV)
51 stats->ac_flag |= ASU;
52 if (tsk->flags & PF_DUMPCORE)
53 stats->ac_flag |= ACORE;
54 if (tsk->flags & PF_SIGNALED)
55 stats->ac_flag |= AXSIG;
56 stats->ac_nice = task_nice(tsk);
57 stats->ac_sched = tsk->policy;
58 stats->ac_pid = task_pid_nr_ns(tsk, pid_ns);
59 stats->ac_tgid = task_tgid_nr_ns(tsk, pid_ns);
60 stats->ac_ppid = task_ppid_nr_ns(tsk, pid_ns);
61 rcu_read_lock();
62 tcred = __task_cred(tsk);
63 stats->ac_uid = from_kuid_munged(user_ns, tcred->uid);
64 stats->ac_gid = from_kgid_munged(user_ns, tcred->gid);
65 rcu_read_unlock();
66
67 task_cputime(tsk, &utime, &stime);
68 stats->ac_utime = div_u64(utime, NSEC_PER_USEC);
69 stats->ac_stime = div_u64(stime, NSEC_PER_USEC);
70
71 task_cputime_scaled(tsk, &utimescaled, &stimescaled);
72 stats->ac_utimescaled = div_u64(utimescaled, NSEC_PER_USEC);
73 stats->ac_stimescaled = div_u64(stimescaled, NSEC_PER_USEC);
74
75 stats->ac_minflt = tsk->min_flt;
76 stats->ac_majflt = tsk->maj_flt;
77
78 strscpy_pad(stats->ac_comm, tsk->comm);
79}
80
81
82#ifdef CONFIG_TASK_XACCT
83
84#define KB 1024
85#define MB (1024*KB)
86#define KB_MASK (~(KB-1))
87/*
88 * fill in extended accounting fields
89 */
90void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
91{
92 struct mm_struct *mm;
93
94 /* convert pages-nsec/1024 to Mbyte-usec, see __acct_update_integrals */
95 stats->coremem = p->acct_rss_mem1 * PAGE_SIZE;
96 do_div(stats->coremem, 1000 * KB);
97 stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE;
98 do_div(stats->virtmem, 1000 * KB);
99 mm = get_task_mm(p);
100 if (mm) {
101 /* adjust to KB unit */
102 stats->hiwater_rss = get_mm_hiwater_rss(mm) * PAGE_SIZE / KB;
103 stats->hiwater_vm = get_mm_hiwater_vm(mm) * PAGE_SIZE / KB;
104 mmput(mm);
105 }
106 stats->read_char = p->ioac.rchar & KB_MASK;
107 stats->write_char = p->ioac.wchar & KB_MASK;
108 stats->read_syscalls = p->ioac.syscr & KB_MASK;
109 stats->write_syscalls = p->ioac.syscw & KB_MASK;
110#ifdef CONFIG_TASK_IO_ACCOUNTING
111 stats->read_bytes = p->ioac.read_bytes & KB_MASK;
112 stats->write_bytes = p->ioac.write_bytes & KB_MASK;
113 stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes & KB_MASK;
114#else
115 stats->read_bytes = 0;
116 stats->write_bytes = 0;
117 stats->cancelled_write_bytes = 0;
118#endif
119}
120#undef KB
121#undef MB
122
123static void __acct_update_integrals(struct task_struct *tsk,
124 u64 utime, u64 stime)
125{
126 u64 time, delta;
127
128 if (unlikely(!tsk->mm || (tsk->flags & PF_KTHREAD)))
129 return;
130
131 time = stime + utime;
132 delta = time - tsk->acct_timexpd;
133
134 if (delta < TICK_NSEC)
135 return;
136
137 tsk->acct_timexpd = time;
138 /*
139 * Divide by 1024 to avoid overflow, and to avoid division.
140 * The final unit reported to userspace is Mbyte-usecs,
141 * the rest of the math is done in xacct_add_tsk.
142 */
143 tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm) >> 10;
144 tsk->acct_vm_mem1 += delta * READ_ONCE(tsk->mm->total_vm) >> 10;
145}
146
147/**
148 * acct_update_integrals - update mm integral fields in task_struct
149 * @tsk: task_struct for accounting
150 */
151void acct_update_integrals(struct task_struct *tsk)
152{
153 u64 utime, stime;
154 unsigned long flags;
155
156 local_irq_save(flags);
157 task_cputime(tsk, &utime, &stime);
158 __acct_update_integrals(tsk, utime, stime);
159 local_irq_restore(flags);
160}
161
162/**
163 * acct_account_cputime - update mm integral after cputime update
164 * @tsk: task_struct for accounting
165 */
166void acct_account_cputime(struct task_struct *tsk)
167{
168 __acct_update_integrals(tsk, tsk->utime, tsk->stime);
169}
170
171/**
172 * acct_clear_integrals - clear the mm integral fields in task_struct
173 * @tsk: task_struct whose accounting fields are cleared
174 */
175void acct_clear_integrals(struct task_struct *tsk)
176{
177 tsk->acct_timexpd = 0;
178 tsk->acct_rss_mem1 = 0;
179 tsk->acct_vm_mem1 = 0;
180}
181#endif