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(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 rcu_read_lock(); 61 tcred = __task_cred(tsk); 62 stats->ac_uid = from_kuid_munged(user_ns, tcred->uid); 63 stats->ac_gid = from_kgid_munged(user_ns, tcred->gid); 64 stats->ac_ppid = pid_alive(tsk) ? 65 task_tgid_nr_ns(rcu_dereference(tsk->real_parent), pid_ns) : 0; 66 rcu_read_unlock(); 67 68 task_cputime(tsk, &utime, &stime); 69 stats->ac_utime = div_u64(utime, NSEC_PER_USEC); 70 stats->ac_stime = div_u64(stime, NSEC_PER_USEC); 71 72 task_cputime_scaled(tsk, &utimescaled, &stimescaled); 73 stats->ac_utimescaled = div_u64(utimescaled, NSEC_PER_USEC); 74 stats->ac_stimescaled = div_u64(stimescaled, NSEC_PER_USEC); 75 76 stats->ac_minflt = tsk->min_flt; 77 stats->ac_majflt = tsk->maj_flt; 78 79 strscpy_pad(stats->ac_comm, tsk->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(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(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(tsk, &utime, &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, tsk->utime, 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