kernel/tsacct.c

   1 /*
   2  * tsacct.c - System accounting over taskstats interface
   3  *
   4  * Copyright (C) Jay Lan,       <jlan@sgi.com>
   5  *
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  */
  18
  19 #include <linux/kernel.h>
  20 #include <linux/sched/signal.h>
  21 #include <linux/sched/mm.h>
  22 #include <linux/sched/cputime.h>
  23 #include <linux/tsacct_kern.h>
  24 #include <linux/acct.h>
  25 #include <linux/jiffies.h>
  26 #include <linux/mm.h>
  27
  28 /*
  29  * fill in basic accounting fields
  30  */
  31 void bacct_add_tsk(struct user_namespace *user_ns,
  32                    struct pid_namespace *pid_ns,
  33                    struct taskstats *stats, struct task_struct *tsk)
  34 {
  35         const struct cred *tcred;
  36         u64 utime, stime, utimescaled, stimescaled;
  37         u64 delta;
  38
  39         BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
  40
  41         /* calculate task elapsed time in nsec */
  42         delta = ktime_get_ns() - tsk->start_time;
  43         /* Convert to micro seconds */
  44         do_div(delta, NSEC_PER_USEC);
  45         stats->ac_etime = delta;
  46         /* Convert to seconds for btime */
  47         do_div(delta, USEC_PER_SEC);
  48         stats->ac_btime = get_seconds() - delta;
  49         if (thread_group_leader(tsk)) {
  50                 stats->ac_exitcode = tsk->exit_code;
  51                 if (tsk->flags & PF_FORKNOEXEC)
  52                         stats->ac_flag |= AFORK;
  53         }
  54         if (tsk->flags & PF_SUPERPRIV)
  55                 stats->ac_flag |= ASU;
  56         if (tsk->flags & PF_DUMPCORE)
  57                 stats->ac_flag |= ACORE;
  58         if (tsk->flags & PF_SIGNALED)
  59                 stats->ac_flag |= AXSIG;
  60         stats->ac_nice   = task_nice(tsk);
  61         stats->ac_sched  = tsk->policy;
  62         stats->ac_pid    = task_pid_nr_ns(tsk, pid_ns);
  63         rcu_read_lock();
  64         tcred = __task_cred(tsk);
  65         stats->ac_uid    = from_kuid_munged(user_ns, tcred->uid);
  66         stats->ac_gid    = from_kgid_munged(user_ns, tcred->gid);
  67         stats->ac_ppid   = pid_alive(tsk) ?
  68                 task_tgid_nr_ns(rcu_dereference(tsk->real_parent), pid_ns) : 0;
  69         rcu_read_unlock();
  70
  71         task_cputime(tsk, &utime, &stime);
  72         stats->ac_utime = div_u64(utime, NSEC_PER_USEC);
  73         stats->ac_stime = div_u64(stime, NSEC_PER_USEC);
  74
  75         task_cputime_scaled(tsk, &utimescaled, &stimescaled);
  76         stats->ac_utimescaled = div_u64(utimescaled, NSEC_PER_USEC);
  77         stats->ac_stimescaled = div_u64(stimescaled, NSEC_PER_USEC);
  78
  79         stats->ac_minflt = tsk->min_flt;
  80         stats->ac_majflt = tsk->maj_flt;
  81
  82         strncpy(stats->ac_comm, tsk->comm, sizeof(stats->ac_comm));
  83 }
  84
  85
  86 #ifdef CONFIG_TASK_XACCT
  87
  88 #define KB 1024
  89 #define MB (1024*KB)
  90 #define KB_MASK (~(KB-1))
  91 /*
  92  * fill in extended accounting fields
  93  */
  94 void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
  95 {
  96         struct mm_struct *mm;
  97
  98         /* convert pages-nsec/1024 to Mbyte-usec, see __acct_update_integrals */
  99         stats->coremem = p->acct_rss_mem1 * PAGE_SIZE;
 100         do_div(stats->coremem, 1000 * KB);
 101         stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE;
 102         do_div(stats->virtmem, 1000 * KB);
 103         mm = get_task_mm(p);
 104         if (mm) {
 105                 /* adjust to KB unit */
 106                 stats->hiwater_rss   = get_mm_hiwater_rss(mm) * PAGE_SIZE / KB;
 107                 stats->hiwater_vm    = get_mm_hiwater_vm(mm)  * PAGE_SIZE / KB;
 108                 mmput(mm);
 109         }
 110         stats->read_char        = p->ioac.rchar & KB_MASK;
 111         stats->write_char       = p->ioac.wchar & KB_MASK;
 112         stats->read_syscalls    = p->ioac.syscr & KB_MASK;
 113         stats->write_syscalls   = p->ioac.syscw & KB_MASK;
 114 #ifdef CONFIG_TASK_IO_ACCOUNTING
 115         stats->read_bytes       = p->ioac.read_bytes & KB_MASK;
 116         stats->write_bytes      = p->ioac.write_bytes & KB_MASK;
 117         stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes & KB_MASK;
 118 #else
 119         stats->read_bytes       = 0;
 120         stats->write_bytes      = 0;
 121         stats->cancelled_write_bytes = 0;
 122 #endif
 123 }
 124 #undef KB
 125 #undef MB
 126
 127 static void __acct_update_integrals(struct task_struct *tsk,
 128                                     u64 utime, u64 stime)
 129 {
 130         u64 time, delta;
 131
 132         if (!likely(tsk->mm))
 133                 return;
 134
 135         time = stime + utime;
 136         delta = time - tsk->acct_timexpd;
 137
 138         if (delta < TICK_NSEC)
 139                 return;
 140
 141         tsk->acct_timexpd = time;
 142         /*
 143          * Divide by 1024 to avoid overflow, and to avoid division.
 144          * The final unit reported to userspace is Mbyte-usecs,
 145          * the rest of the math is done in xacct_add_tsk.
 146          */
 147         tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm) >> 10;
 148         tsk->acct_vm_mem1 += delta * tsk->mm->total_vm >> 10;
 149 }
 150
 151 /**
 152  * acct_update_integrals - update mm integral fields in task_struct
 153  * @tsk: task_struct for accounting
 154  */
 155 void acct_update_integrals(struct task_struct *tsk)
 156 {
 157         u64 utime, stime;
 158         unsigned long flags;
 159
 160         local_irq_save(flags);
 161         task_cputime(tsk, &utime, &stime);
 162         __acct_update_integrals(tsk, utime, stime);
 163         local_irq_restore(flags);
 164 }
 165
 166 /**
 167  * acct_account_cputime - update mm integral after cputime update
 168  * @tsk: task_struct for accounting
 169  */
 170 void acct_account_cputime(struct task_struct *tsk)
 171 {
 172         __acct_update_integrals(tsk, tsk->utime, tsk->stime);
 173 }
 174
 175 /**
 176  * acct_clear_integrals - clear the mm integral fields in task_struct
 177  * @tsk: task_struct whose accounting fields are cleared
 178  */
 179 void acct_clear_integrals(struct task_struct *tsk)
 180 {
 181         tsk->acct_timexpd = 0;
 182         tsk->acct_rss_mem1 = 0;
 183         tsk->acct_vm_mem1 = 0;
 184 }
 185 #endif