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.h>
  21 #include <linux/tsacct_kern.h>
  22 #include <linux/acct.h>
  23 #include <linux/jiffies.h>
  24 #include <linux/mm.h>
  25
  26 /*
  27  * fill in basic accounting fields
  28  */
  29 void bacct_add_tsk(struct user_namespace *user_ns,
  30                    struct pid_namespace *pid_ns,
  31                    struct taskstats *stats, struct task_struct *tsk)
  32 {
  33         const struct cred *tcred;
  34         cputime_t utime, stime, utimescaled, stimescaled;
  35         u64 delta;
  36
  37         BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
  38
  39         /* calculate task elapsed time in nsec */
  40         delta = ktime_get_ns() - tsk->start_time;
  41         /* Convert to micro seconds */
  42         do_div(delta, NSEC_PER_USEC);
  43         stats->ac_etime = delta;
  44         /* Convert to seconds for btime */
  45         do_div(delta, USEC_PER_SEC);
  46         stats->ac_btime = get_seconds() - delta;
  47         if (thread_group_leader(tsk)) {
  48                 stats->ac_exitcode = tsk->exit_code;
  49                 if (tsk->flags & PF_FORKNOEXEC)
  50                         stats->ac_flag |= AFORK;
  51         }
  52         if (tsk->flags & PF_SUPERPRIV)
  53                 stats->ac_flag |= ASU;
  54         if (tsk->flags & PF_DUMPCORE)
  55                 stats->ac_flag |= ACORE;
  56         if (tsk->flags & PF_SIGNALED)
  57                 stats->ac_flag |= AXSIG;
  58         stats->ac_nice   = task_nice(tsk);
  59         stats->ac_sched  = tsk->policy;
  60         stats->ac_pid    = task_pid_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         stats->ac_ppid   = pid_alive(tsk) ?
  66                 task_tgid_nr_ns(rcu_dereference(tsk->real_parent), pid_ns) : 0;
  67         rcu_read_unlock();
  68
  69         task_cputime(tsk, &utime, &stime);
  70         stats->ac_utime = cputime_to_usecs(utime);
  71         stats->ac_stime = cputime_to_usecs(stime);
  72
  73         task_cputime_scaled(tsk, &utimescaled, &stimescaled);
  74         stats->ac_utimescaled = cputime_to_usecs(utimescaled);
  75         stats->ac_stimescaled = cputime_to_usecs(stimescaled);
  76
  77         stats->ac_minflt = tsk->min_flt;
  78         stats->ac_majflt = tsk->maj_flt;
  79
  80         strncpy(stats->ac_comm, tsk->comm, sizeof(stats->ac_comm));
  81 }
  82
  83
  84 #ifdef CONFIG_TASK_XACCT
  85
  86 #define KB 1024
  87 #define MB (1024*KB)
  88 #define KB_MASK (~(KB-1))
  89 /*
  90  * fill in extended accounting fields
  91  */
  92 void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
  93 {
  94         struct mm_struct *mm;
  95
  96         /* convert pages-nsec/1024 to Mbyte-usec, see __acct_update_integrals */
  97         stats->coremem = p->acct_rss_mem1 * PAGE_SIZE;
  98         do_div(stats->coremem, 1000 * KB);
  99         stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE;
 100         do_div(stats->virtmem, 1000 * KB);
 101         mm = get_task_mm(p);
 102         if (mm) {
 103                 /* adjust to KB unit */
 104                 stats->hiwater_rss   = get_mm_hiwater_rss(mm) * PAGE_SIZE / KB;
 105                 stats->hiwater_vm    = get_mm_hiwater_vm(mm)  * PAGE_SIZE / KB;
 106                 mmput(mm);
 107         }
 108         stats->read_char        = p->ioac.rchar & KB_MASK;
 109         stats->write_char       = p->ioac.wchar & KB_MASK;
 110         stats->read_syscalls    = p->ioac.syscr & KB_MASK;
 111         stats->write_syscalls   = p->ioac.syscw & KB_MASK;
 112 #ifdef CONFIG_TASK_IO_ACCOUNTING
 113         stats->read_bytes       = p->ioac.read_bytes & KB_MASK;
 114         stats->write_bytes      = p->ioac.write_bytes & KB_MASK;
 115         stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes & KB_MASK;
 116 #else
 117         stats->read_bytes       = 0;
 118         stats->write_bytes      = 0;
 119         stats->cancelled_write_bytes = 0;
 120 #endif
 121 }
 122 #undef KB
 123 #undef MB
 124
 125 static void __acct_update_integrals(struct task_struct *tsk,
 126                                     cputime_t utime, cputime_t stime)
 127 {
 128         cputime_t time, dtime;
 129         u64 delta;
 130
 131         if (!likely(tsk->mm))
 132                 return;
 133
 134         time = stime + utime;
 135         dtime = time - tsk->acct_timexpd;
 136         /* Avoid division: cputime_t is often in nanoseconds already. */
 137         delta = cputime_to_nsecs(dtime);
 138
 139         if (delta < TICK_NSEC)
 140                 return;
 141
 142         tsk->acct_timexpd = time;
 143         /*
 144          * Divide by 1024 to avoid overflow, and to avoid division.
 145          * The final unit reported to userspace is Mbyte-usecs,
 146          * the rest of the math is done in xacct_add_tsk.
 147          */
 148         tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm) >> 10;
 149         tsk->acct_vm_mem1 += delta * tsk->mm->total_vm >> 10;
 150 }
 151
 152 /**
 153  * acct_update_integrals - update mm integral fields in task_struct
 154  * @tsk: task_struct for accounting
 155  */
 156 void acct_update_integrals(struct task_struct *tsk)
 157 {
 158         cputime_t utime, stime;
 159         unsigned long flags;
 160
 161         local_irq_save(flags);
 162         task_cputime(tsk, &utime, &stime);
 163         __acct_update_integrals(tsk, utime, stime);
 164         local_irq_restore(flags);
 165 }
 166
 167 /**
 168  * acct_account_cputime - update mm integral after cputime update
 169  * @tsk: task_struct for accounting
 170  */
 171 void acct_account_cputime(struct task_struct *tsk)
 172 {
 173         __acct_update_integrals(tsk, tsk->utime, tsk->stime);
 174 }
 175
 176 /**
 177  * acct_clear_integrals - clear the mm integral fields in task_struct
 178  * @tsk: task_struct whose accounting fields are cleared
 179  */
 180 void acct_clear_integrals(struct task_struct *tsk)
 181 {
 182         tsk->acct_timexpd = 0;
 183         tsk->acct_rss_mem1 = 0;
 184         tsk->acct_vm_mem1 = 0;
 185 }
 186 #endif