1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * tsacct.c - System accounting over taskstats interface |
4 | * |
5 | * Copyright (C) Jay Lan, <jlan@sgi.com> |
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 | */ |
20 | void 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(dividend: 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(p: 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(p: tsk); |
57 | stats->ac_sched = tsk->policy; |
58 | stats->ac_pid = task_pid_nr_ns(tsk, ns: pid_ns); |
59 | stats->ac_tgid = task_tgid_nr_ns(tsk, ns: pid_ns); |
60 | rcu_read_lock(); |
61 | tcred = __task_cred(tsk); |
62 | stats->ac_uid = from_kuid_munged(to: user_ns, uid: tcred->uid); |
63 | stats->ac_gid = from_kgid_munged(to: user_ns, gid: tcred->gid); |
64 | stats->ac_ppid = pid_alive(p: tsk) ? |
65 | task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns: pid_ns) : 0; |
66 | rcu_read_unlock(); |
67 | |
68 | task_cputime(t: tsk, utime: &utime, stime: &stime); |
69 | stats->ac_utime = div_u64(dividend: utime, NSEC_PER_USEC); |
70 | stats->ac_stime = div_u64(dividend: stime, NSEC_PER_USEC); |
71 | |
72 | task_cputime_scaled(t: tsk, utimescaled: &utimescaled, stimescaled: &stimescaled); |
73 | stats->ac_utimescaled = div_u64(dividend: utimescaled, NSEC_PER_USEC); |
74 | stats->ac_stimescaled = div_u64(dividend: stimescaled, NSEC_PER_USEC); |
75 | |
76 | stats->ac_minflt = tsk->min_flt; |
77 | stats->ac_majflt = tsk->maj_flt; |
78 | |
79 | strncpy(p: stats->ac_comm, q: tsk->comm, size: sizeof(stats->ac_comm)); |
80 | } |
81 | |
82 | |
83 | #ifdef CONFIG_TASK_XACCT |
84 | |
85 | #define KB 1024 |
86 | #define MB (1024*KB) |
87 | #define KB_MASK (~(KB-1)) |
88 | /* |
89 | * fill in extended accounting fields |
90 | */ |
91 | void xacct_add_tsk(struct taskstats *stats, struct task_struct *p) |
92 | { |
93 | struct mm_struct *mm; |
94 | |
95 | /* convert pages-nsec/1024 to Mbyte-usec, see __acct_update_integrals */ |
96 | stats->coremem = p->acct_rss_mem1 * PAGE_SIZE; |
97 | do_div(stats->coremem, 1000 * KB); |
98 | stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE; |
99 | do_div(stats->virtmem, 1000 * KB); |
100 | mm = get_task_mm(task: p); |
101 | if (mm) { |
102 | /* adjust to KB unit */ |
103 | stats->hiwater_rss = get_mm_hiwater_rss(mm) * PAGE_SIZE / KB; |
104 | stats->hiwater_vm = get_mm_hiwater_vm(mm) * PAGE_SIZE / KB; |
105 | mmput(mm); |
106 | } |
107 | stats->read_char = p->ioac.rchar & KB_MASK; |
108 | stats->write_char = p->ioac.wchar & KB_MASK; |
109 | stats->read_syscalls = p->ioac.syscr & KB_MASK; |
110 | stats->write_syscalls = p->ioac.syscw & KB_MASK; |
111 | #ifdef CONFIG_TASK_IO_ACCOUNTING |
112 | stats->read_bytes = p->ioac.read_bytes & KB_MASK; |
113 | stats->write_bytes = p->ioac.write_bytes & KB_MASK; |
114 | stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes & KB_MASK; |
115 | #else |
116 | stats->read_bytes = 0; |
117 | stats->write_bytes = 0; |
118 | stats->cancelled_write_bytes = 0; |
119 | #endif |
120 | } |
121 | #undef KB |
122 | #undef MB |
123 | |
124 | static void __acct_update_integrals(struct task_struct *tsk, |
125 | u64 utime, u64 stime) |
126 | { |
127 | u64 time, delta; |
128 | |
129 | if (!likely(tsk->mm)) |
130 | return; |
131 | |
132 | time = stime + utime; |
133 | delta = time - tsk->acct_timexpd; |
134 | |
135 | if (delta < TICK_NSEC) |
136 | return; |
137 | |
138 | tsk->acct_timexpd = time; |
139 | /* |
140 | * Divide by 1024 to avoid overflow, and to avoid division. |
141 | * The final unit reported to userspace is Mbyte-usecs, |
142 | * the rest of the math is done in xacct_add_tsk. |
143 | */ |
144 | tsk->acct_rss_mem1 += delta * get_mm_rss(mm: tsk->mm) >> 10; |
145 | tsk->acct_vm_mem1 += delta * READ_ONCE(tsk->mm->total_vm) >> 10; |
146 | } |
147 | |
148 | /** |
149 | * acct_update_integrals - update mm integral fields in task_struct |
150 | * @tsk: task_struct for accounting |
151 | */ |
152 | void acct_update_integrals(struct task_struct *tsk) |
153 | { |
154 | u64 utime, stime; |
155 | unsigned long flags; |
156 | |
157 | local_irq_save(flags); |
158 | task_cputime(t: tsk, utime: &utime, stime: &stime); |
159 | __acct_update_integrals(tsk, utime, stime); |
160 | local_irq_restore(flags); |
161 | } |
162 | |
163 | /** |
164 | * acct_account_cputime - update mm integral after cputime update |
165 | * @tsk: task_struct for accounting |
166 | */ |
167 | void acct_account_cputime(struct task_struct *tsk) |
168 | { |
169 | __acct_update_integrals(tsk, utime: tsk->utime, stime: tsk->stime); |
170 | } |
171 | |
172 | /** |
173 | * acct_clear_integrals - clear the mm integral fields in task_struct |
174 | * @tsk: task_struct whose accounting fields are cleared |
175 | */ |
176 | void acct_clear_integrals(struct task_struct *tsk) |
177 | { |
178 | tsk->acct_timexpd = 0; |
179 | tsk->acct_rss_mem1 = 0; |
180 | tsk->acct_vm_mem1 = 0; |
181 | } |
182 | #endif |
183 | |