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 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 delta = ktime_get_ns() - tsk->start_time; 33 /* Convert to micro seconds */ 34 do_div(delta, NSEC_PER_USEC); 35 stats->ac_etime = delta; 36 /* Convert to seconds for btime (note y2106 limit) */ 37 btime = ktime_get_real_seconds() - div_u64(delta, USEC_PER_SEC); 38 stats->ac_btime = clamp_t(time64_t, btime, 0, U32_MAX); 39 stats->ac_btime64 = btime; 40 41 if (thread_group_leader(tsk)) { 42 stats->ac_exitcode = tsk->exit_code; 43 if (tsk->flags & PF_FORKNOEXEC) 44 stats->ac_flag |= AFORK; 45 } 46 if (tsk->flags & PF_SUPERPRIV) 47 stats->ac_flag |= ASU; 48 if (tsk->flags & PF_DUMPCORE) 49 stats->ac_flag |= ACORE; 50 if (tsk->flags & PF_SIGNALED) 51 stats->ac_flag |= AXSIG; 52 stats->ac_nice = task_nice(tsk); 53 stats->ac_sched = tsk->policy; 54 stats->ac_pid = task_pid_nr_ns(tsk, pid_ns); 55 rcu_read_lock(); 56 tcred = __task_cred(tsk); 57 stats->ac_uid = from_kuid_munged(user_ns, tcred->uid); 58 stats->ac_gid = from_kgid_munged(user_ns, tcred->gid); 59 stats->ac_ppid = pid_alive(tsk) ? 60 task_tgid_nr_ns(rcu_dereference(tsk->real_parent), pid_ns) : 0; 61 rcu_read_unlock(); 62 63 task_cputime(tsk, &utime, &stime); 64 stats->ac_utime = div_u64(utime, NSEC_PER_USEC); 65 stats->ac_stime = div_u64(stime, NSEC_PER_USEC); 66 67 task_cputime_scaled(tsk, &utimescaled, &stimescaled); 68 stats->ac_utimescaled = div_u64(utimescaled, NSEC_PER_USEC); 69 stats->ac_stimescaled = div_u64(stimescaled, NSEC_PER_USEC); 70 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 #define KB_MASK (~(KB-1)) 83 /* 84 * fill in extended accounting fields 85 */ 86 void xacct_add_tsk(struct taskstats *stats, struct task_struct *p) 87 { 88 struct mm_struct *mm; 89 90 /* convert pages-nsec/1024 to Mbyte-usec, see __acct_update_integrals */ 91 stats->coremem = p->acct_rss_mem1 * PAGE_SIZE; 92 do_div(stats->coremem, 1000 * KB); 93 stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE; 94 do_div(stats->virtmem, 1000 * KB); 95 mm = get_task_mm(p); 96 if (mm) { 97 /* adjust to KB unit */ 98 stats->hiwater_rss = get_mm_hiwater_rss(mm) * PAGE_SIZE / KB; 99 stats->hiwater_vm = get_mm_hiwater_vm(mm) * PAGE_SIZE / KB; 100 mmput(mm); 101 } 102 stats->read_char = p->ioac.rchar & KB_MASK; 103 stats->write_char = p->ioac.wchar & KB_MASK; 104 stats->read_syscalls = p->ioac.syscr & KB_MASK; 105 stats->write_syscalls = p->ioac.syscw & KB_MASK; 106 #ifdef CONFIG_TASK_IO_ACCOUNTING 107 stats->read_bytes = p->ioac.read_bytes & KB_MASK; 108 stats->write_bytes = p->ioac.write_bytes & KB_MASK; 109 stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes & KB_MASK; 110 #else 111 stats->read_bytes = 0; 112 stats->write_bytes = 0; 113 stats->cancelled_write_bytes = 0; 114 #endif 115 } 116 #undef KB 117 #undef MB 118 119 static void __acct_update_integrals(struct task_struct *tsk, 120 u64 utime, u64 stime) 121 { 122 u64 time, delta; 123 124 if (!likely(tsk->mm)) 125 return; 126 127 time = stime + utime; 128 delta = time - tsk->acct_timexpd; 129 130 if (delta < TICK_NSEC) 131 return; 132 133 tsk->acct_timexpd = time; 134 /* 135 * Divide by 1024 to avoid overflow, and to avoid division. 136 * The final unit reported to userspace is Mbyte-usecs, 137 * the rest of the math is done in xacct_add_tsk. 138 */ 139 tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm) >> 10; 140 tsk->acct_vm_mem1 += delta * READ_ONCE(tsk->mm->total_vm) >> 10; 141 } 142 143 /** 144 * acct_update_integrals - update mm integral fields in task_struct 145 * @tsk: task_struct for accounting 146 */ 147 void acct_update_integrals(struct task_struct *tsk) 148 { 149 u64 utime, stime; 150 unsigned long flags; 151 152 local_irq_save(flags); 153 task_cputime(tsk, &utime, &stime); 154 __acct_update_integrals(tsk, utime, stime); 155 local_irq_restore(flags); 156 } 157 158 /** 159 * acct_account_cputime - update mm integral after cputime update 160 * @tsk: task_struct for accounting 161 */ 162 void acct_account_cputime(struct task_struct *tsk) 163 { 164 __acct_update_integrals(tsk, tsk->utime, tsk->stime); 165 } 166 167 /** 168 * acct_clear_integrals - clear the mm integral fields in task_struct 169 * @tsk: task_struct whose accounting fields are cleared 170 */ 171 void acct_clear_integrals(struct task_struct *tsk) 172 { 173 tsk->acct_timexpd = 0; 174 tsk->acct_rss_mem1 = 0; 175 tsk->acct_vm_mem1 = 0; 176 } 177 #endif 178