linux/kernel/tsacct.c
john stultz 2c6b47de17 Cleanup non-arch xtime uses, use get_seconds() or current_kernel_time().
This avoids use of the kernel-internal "xtime" variable directly outside
of the actual time-related functions.  Instead, use the helper functions
that we already have available to us.

This doesn't actually change any behaviour, but this will allow us to
fix the fact that "xtime" isn't updated very often with CONFIG_NO_HZ
(because much of the realtime information is maintained as separate
offsets to 'xtime'), which has caused interfaces that use xtime directly
to get a time that is out of sync with the real-time clock by up to a
third of a second or so.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-25 10:09:20 -07:00

138 lines
3.8 KiB
C

/*
* tsacct.c - System accounting over taskstats interface
*
* Copyright (C) Jay Lan, <jlan@sgi.com>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/tsacct_kern.h>
#include <linux/acct.h>
#include <linux/jiffies.h>
/*
* fill in basic accounting fields
*/
void bacct_add_tsk(struct taskstats *stats, struct task_struct *tsk)
{
struct timespec uptime, ts;
s64 ac_etime;
BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
/* calculate task elapsed time in timespec */
do_posix_clock_monotonic_gettime(&uptime);
ts = timespec_sub(uptime, tsk->start_time);
/* rebase elapsed time to usec */
ac_etime = timespec_to_ns(&ts);
do_div(ac_etime, NSEC_PER_USEC);
stats->ac_etime = ac_etime;
stats->ac_btime = get_seconds() - ts.tv_sec;
if (thread_group_leader(tsk)) {
stats->ac_exitcode = tsk->exit_code;
if (tsk->flags & PF_FORKNOEXEC)
stats->ac_flag |= AFORK;
}
if (tsk->flags & PF_SUPERPRIV)
stats->ac_flag |= ASU;
if (tsk->flags & PF_DUMPCORE)
stats->ac_flag |= ACORE;
if (tsk->flags & PF_SIGNALED)
stats->ac_flag |= AXSIG;
stats->ac_nice = task_nice(tsk);
stats->ac_sched = tsk->policy;
stats->ac_uid = tsk->uid;
stats->ac_gid = tsk->gid;
stats->ac_pid = tsk->pid;
rcu_read_lock();
stats->ac_ppid = pid_alive(tsk) ?
rcu_dereference(tsk->real_parent)->tgid : 0;
rcu_read_unlock();
stats->ac_utime = cputime_to_msecs(tsk->utime) * USEC_PER_MSEC;
stats->ac_stime = cputime_to_msecs(tsk->stime) * USEC_PER_MSEC;
stats->ac_minflt = tsk->min_flt;
stats->ac_majflt = tsk->maj_flt;
strncpy(stats->ac_comm, tsk->comm, sizeof(stats->ac_comm));
}
#ifdef CONFIG_TASK_XACCT
#define KB 1024
#define MB (1024*KB)
/*
* fill in extended accounting fields
*/
void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
{
struct mm_struct *mm;
/* convert pages-jiffies to Mbyte-usec */
stats->coremem = jiffies_to_usecs(p->acct_rss_mem1) * PAGE_SIZE / MB;
stats->virtmem = jiffies_to_usecs(p->acct_vm_mem1) * PAGE_SIZE / MB;
mm = get_task_mm(p);
if (mm) {
/* adjust to KB unit */
stats->hiwater_rss = mm->hiwater_rss * PAGE_SIZE / KB;
stats->hiwater_vm = mm->hiwater_vm * PAGE_SIZE / KB;
mmput(mm);
}
stats->read_char = p->rchar;
stats->write_char = p->wchar;
stats->read_syscalls = p->syscr;
stats->write_syscalls = p->syscw;
#ifdef CONFIG_TASK_IO_ACCOUNTING
stats->read_bytes = p->ioac.read_bytes;
stats->write_bytes = p->ioac.write_bytes;
stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes;
#else
stats->read_bytes = 0;
stats->write_bytes = 0;
stats->cancelled_write_bytes = 0;
#endif
}
#undef KB
#undef MB
/**
* acct_update_integrals - update mm integral fields in task_struct
* @tsk: task_struct for accounting
*/
void acct_update_integrals(struct task_struct *tsk)
{
if (likely(tsk->mm)) {
long delta = cputime_to_jiffies(
cputime_sub(tsk->stime, tsk->acct_stimexpd));
if (delta == 0)
return;
tsk->acct_stimexpd = tsk->stime;
tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm);
tsk->acct_vm_mem1 += delta * tsk->mm->total_vm;
}
}
/**
* acct_clear_integrals - clear the mm integral fields in task_struct
* @tsk: task_struct whose accounting fields are cleared
*/
void acct_clear_integrals(struct task_struct *tsk)
{
tsk->acct_stimexpd = 0;
tsk->acct_rss_mem1 = 0;
tsk->acct_vm_mem1 = 0;
}
#endif