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freebsd-skq/sys/kern/kern_tc.c
phk 86337bf437 s/nanoruntime/nanouptime/g 
s/microruntime/microuptime/g

Reviewed by:	bde
1998-05-17 11:53:46 +00:00

838 lines
21 KiB
C
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static volatile int print_tci = 1;
/*-
* Copyright (c) 1997, 1998 Poul-Henning Kamp <phk@FreeBSD.org>
* Copyright (c) 1982, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kern_clock.c 8.5 (Berkeley) 1/21/94
* $Id: kern_clock.c,v 1.67 1998/04/08 09:01:53 phk Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/dkstat.h>
#include <sys/callout.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
#include <sys/timex.h>
#include <vm/vm.h>
#include <sys/lock.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <sys/sysctl.h>
#include <machine/cpu.h>
#include <machine/limits.h>
#ifdef GPROF
#include <sys/gmon.h>
#endif
#if defined(SMP) && defined(BETTER_CLOCK)
#include <machine/smp.h>
#endif
static void initclocks __P((void *dummy));
SYSINIT(clocks, SI_SUB_CLOCKS, SI_ORDER_FIRST, initclocks, NULL)
static void tco_forward __P((void));
static void tco_setscales __P((struct timecounter *tc));
/* Some of these don't belong here, but it's easiest to concentrate them. */
#if defined(SMP) && defined(BETTER_CLOCK)
long cp_time[CPUSTATES];
#else
static long cp_time[CPUSTATES];
#endif
long dk_seek[DK_NDRIVE];
static long dk_time[DK_NDRIVE]; /* time busy (in statclock ticks) */
long dk_wds[DK_NDRIVE];
long dk_wpms[DK_NDRIVE];
long dk_xfer[DK_NDRIVE];
int dk_busy;
int dk_ndrive = 0;
char dk_names[DK_NDRIVE][DK_NAMELEN];
long tk_cancc;
long tk_nin;
long tk_nout;
long tk_rawcc;
struct timecounter *timecounter;
time_t time_second;
/*
* Clock handling routines.
*
* This code is written to operate with two timers that run independently of
* each other.
*
* The main timer, running hz times per second, is used to trigger interval
* timers, timeouts and rescheduling as needed.
*
* The second timer handles kernel and user profiling,
* and does resource use estimation. If the second timer is programmable,
* it is randomized to avoid aliasing between the two clocks. For example,
* the randomization prevents an adversary from always giving up the cpu
* just before its quantum expires. Otherwise, it would never accumulate
* cpu ticks. The mean frequency of the second timer is stathz.
*
* If no second timer exists, stathz will be zero; in this case we drive
* profiling and statistics off the main clock. This WILL NOT be accurate;
* do not do it unless absolutely necessary.
*
* The statistics clock may (or may not) be run at a higher rate while
* profiling. This profile clock runs at profhz. We require that profhz
* be an integral multiple of stathz.
*
* If the statistics clock is running fast, it must be divided by the ratio
* profhz/stathz for statistics. (For profiling, every tick counts.)
*
* Time-of-day is maintained using a "timecounter", which may or may
* not be related to the hardware generating the above mentioned
* interrupts.
*/
int stathz;
int profhz;
static int profprocs;
int ticks;
static int psdiv, pscnt; /* prof => stat divider */
int psratio; /* ratio: prof / stat */
/*
* Initialize clock frequencies and start both clocks running.
*/
/* ARGSUSED*/
static void
initclocks(dummy)
void *dummy;
{
register int i;
/*
* Set divisors to 1 (normal case) and let the machine-specific
* code do its bit.
*/
psdiv = pscnt = 1;
cpu_initclocks();
/*
* Compute profhz/stathz, and fix profhz if needed.
*/
i = stathz ? stathz : hz;
if (profhz == 0)
profhz = i;
psratio = profhz / i;
}
/*
* The real-time timer, interrupting hz times per second.
*/
void
hardclock(frame)
register struct clockframe *frame;
{
register struct proc *p;
p = curproc;
if (p) {
register struct pstats *pstats;
/*
* Run current process's virtual and profile time, as needed.
*/
pstats = p->p_stats;
if (CLKF_USERMODE(frame) &&
timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value) &&
itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0)
psignal(p, SIGVTALRM);
if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value) &&
itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0)
psignal(p, SIGPROF);
}
#if defined(SMP) && defined(BETTER_CLOCK)
forward_hardclock(pscnt);
#endif
/*
* If no separate statistics clock is available, run it from here.
*/
if (stathz == 0)
statclock(frame);
tco_forward();
ticks++;
/*
* Process callouts at a very low cpu priority, so we don't keep the
* relatively high clock interrupt priority any longer than necessary.
*/
if (TAILQ_FIRST(&callwheel[ticks & callwheelmask]) != NULL) {
if (CLKF_BASEPRI(frame)) {
/*
* Save the overhead of a software interrupt;
* it will happen as soon as we return, so do it now.
*/
(void)splsoftclock();
softclock();
} else
setsoftclock();
} else if (softticks + 1 == ticks)
++softticks;
}
/*
* Compute number of ticks in the specified amount of time.
*/
int
tvtohz(tv)
struct timeval *tv;
{
register unsigned long ticks;
register long sec, usec;
/*
* If the number of usecs in the whole seconds part of the time
* difference fits in a long, then the total number of usecs will
* fit in an unsigned long. Compute the total and convert it to
* ticks, rounding up and adding 1 to allow for the current tick
* to expire. Rounding also depends on unsigned long arithmetic
* to avoid overflow.
*
* Otherwise, if the number of ticks in the whole seconds part of
* the time difference fits in a long, then convert the parts to
* ticks separately and add, using similar rounding methods and
* overflow avoidance. This method would work in the previous
* case but it is slightly slower and assumes that hz is integral.
*
* Otherwise, round the time difference down to the maximum
* representable value.
*
* If ints have 32 bits, then the maximum value for any timeout in
* 10ms ticks is 248 days.
*/
sec = tv->tv_sec;
usec = tv->tv_usec;
if (usec < 0) {
sec--;
usec += 1000000;
}
if (sec < 0) {
#ifdef DIAGNOSTIC
if (usec > 0) {
sec++;
usec -= 1000000;
}
printf("tvotohz: negative time difference %ld sec %ld usec\n",
sec, usec);
#endif
ticks = 1;
} else if (sec <= LONG_MAX / 1000000)
ticks = (sec * 1000000 + (unsigned long)usec + (tick - 1))
/ tick + 1;
else if (sec <= LONG_MAX / hz)
ticks = sec * hz
+ ((unsigned long)usec + (tick - 1)) / tick + 1;
else
ticks = LONG_MAX;
if (ticks > INT_MAX)
ticks = INT_MAX;
return (ticks);
}
/*
* Compute number of hz until specified time. Used to
* compute third argument to timeout() from an absolute time.
*/
int
hzto(tv)
struct timeval *tv;
{
struct timeval t2;
getmicrotime(&t2);
t2.tv_sec = tv->tv_sec - t2.tv_sec;
t2.tv_usec = tv->tv_usec - t2.tv_usec;
return (tvtohz(&t2));
}
/*
* Start profiling on a process.
*
* Kernel profiling passes proc0 which never exits and hence
* keeps the profile clock running constantly.
*/
void
startprofclock(p)
register struct proc *p;
{
int s;
if ((p->p_flag & P_PROFIL) == 0) {
p->p_flag |= P_PROFIL;
if (++profprocs == 1 && stathz != 0) {
s = splstatclock();
psdiv = pscnt = psratio;
setstatclockrate(profhz);
splx(s);
}
}
}
/*
* Stop profiling on a process.
*/
void
stopprofclock(p)
register struct proc *p;
{
int s;
if (p->p_flag & P_PROFIL) {
p->p_flag &= ~P_PROFIL;
if (--profprocs == 0 && stathz != 0) {
s = splstatclock();
psdiv = pscnt = 1;
setstatclockrate(stathz);
splx(s);
}
}
}
/*
* Statistics clock. Grab profile sample, and if divider reaches 0,
* do process and kernel statistics.
*/
void
statclock(frame)
register struct clockframe *frame;
{
#ifdef GPROF
register struct gmonparam *g;
#endif
register struct proc *p;
register int i;
struct pstats *pstats;
long rss;
struct rusage *ru;
struct vmspace *vm;
if (CLKF_USERMODE(frame)) {
p = curproc;
if (p->p_flag & P_PROFIL)
addupc_intr(p, CLKF_PC(frame), 1);
#if defined(SMP) && defined(BETTER_CLOCK)
if (stathz != 0)
forward_statclock(pscnt);
#endif
if (--pscnt > 0)
return;
/*
* Came from user mode; CPU was in user state.
* If this process is being profiled record the tick.
*/
p->p_uticks++;
if (p->p_nice > NZERO)
cp_time[CP_NICE]++;
else
cp_time[CP_USER]++;
} else {
#ifdef GPROF
/*
* Kernel statistics are just like addupc_intr, only easier.
*/
g = &_gmonparam;
if (g->state == GMON_PROF_ON) {
i = CLKF_PC(frame) - g->lowpc;
if (i < g->textsize) {
i /= HISTFRACTION * sizeof(*g->kcount);
g->kcount[i]++;
}
}
#endif
#if defined(SMP) && defined(BETTER_CLOCK)
if (stathz != 0)
forward_statclock(pscnt);
#endif
if (--pscnt > 0)
return;
/*
* Came from kernel mode, so we were:
* - handling an interrupt,
* - doing syscall or trap work on behalf of the current
* user process, or
* - spinning in the idle loop.
* Whichever it is, charge the time as appropriate.
* Note that we charge interrupts to the current process,
* regardless of whether they are ``for'' that process,
* so that we know how much of its real time was spent
* in ``non-process'' (i.e., interrupt) work.
*/
p = curproc;
if (CLKF_INTR(frame)) {
if (p != NULL)
p->p_iticks++;
cp_time[CP_INTR]++;
} else if (p != NULL) {
p->p_sticks++;
cp_time[CP_SYS]++;
} else
cp_time[CP_IDLE]++;
}
pscnt = psdiv;
/*
* We maintain statistics shown by user-level statistics
* programs: the amount of time in each cpu state, and
* the amount of time each of DK_NDRIVE ``drives'' is busy.
*
* XXX should either run linked list of drives, or (better)
* grab timestamps in the start & done code.
*/
for (i = 0; i < DK_NDRIVE; i++)
if (dk_busy & (1 << i))
dk_time[i]++;
/*
* We adjust the priority of the current process. The priority of
* a process gets worse as it accumulates CPU time. The cpu usage
* estimator (p_estcpu) is increased here. The formula for computing
* priorities (in kern_synch.c) will compute a different value each
* time p_estcpu increases by 4. The cpu usage estimator ramps up
* quite quickly when the process is running (linearly), and decays
* away exponentially, at a rate which is proportionally slower when
* the system is busy. The basic principal is that the system will
* 90% forget that the process used a lot of CPU time in 5 * loadav
* seconds. This causes the system to favor processes which haven't
* run much recently, and to round-robin among other processes.
*/
if (p != NULL) {
p->p_cpticks++;
if (++p->p_estcpu == 0)
p->p_estcpu--;
if ((p->p_estcpu & 3) == 0) {
resetpriority(p);
if (p->p_priority >= PUSER)
p->p_priority = p->p_usrpri;
}
/* Update resource usage integrals and maximums. */
if ((pstats = p->p_stats) != NULL &&
(ru = &pstats->p_ru) != NULL &&
(vm = p->p_vmspace) != NULL) {
ru->ru_ixrss += vm->vm_tsize * PAGE_SIZE / 1024;
ru->ru_idrss += vm->vm_dsize * PAGE_SIZE / 1024;
ru->ru_isrss += vm->vm_ssize * PAGE_SIZE / 1024;
rss = vm->vm_pmap.pm_stats.resident_count *
PAGE_SIZE / 1024;
if (ru->ru_maxrss < rss)
ru->ru_maxrss = rss;
}
}
}
/*
* Return information about system clocks.
*/
static int
sysctl_kern_clockrate SYSCTL_HANDLER_ARGS
{
struct clockinfo clkinfo;
/*
* Construct clockinfo structure.
*/
clkinfo.hz = hz;
clkinfo.tick = tick;
clkinfo.tickadj = tickadj;
clkinfo.profhz = profhz;
clkinfo.stathz = stathz ? stathz : hz;
return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req));
}
SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, CTLTYPE_STRUCT|CTLFLAG_RD,
0, 0, sysctl_kern_clockrate, "S,clockinfo","");
/*
* We have four functions for looking at the clock, two for microseconds
* and two for nanoseconds. For each there is fast but less precise
* version "get{nano|micro}time" which will return a time which is up
* to 1/HZ previous to the call, whereas the raw version "{nano|micro}time"
* will return a timestamp which is as precise as possible.
*/
void
getmicrotime(struct timeval *tvp)
{
struct timecounter *tc;
tc = timecounter;
*tvp = tc->microtime;
}
void
getnanotime(struct timespec *tsp)
{
struct timecounter *tc;
tc = timecounter;
*tsp = tc->nanotime;
}
void
microtime(struct timeval *tv)
{
struct timecounter *tc;
tc = (struct timecounter *)timecounter;
tv->tv_sec = tc->offset_sec;
tv->tv_usec = tc->offset_micro;
tv->tv_usec +=
((u_int64_t)tc->get_timedelta(tc) * tc->scale_micro) >> 32;
tv->tv_usec += boottime.tv_usec;
tv->tv_sec += boottime.tv_sec;
while (tv->tv_usec >= 1000000) {
tv->tv_usec -= 1000000;
tv->tv_sec++;
}
}
void
nanotime(struct timespec *tv)
{
u_int count;
u_int64_t delta;
struct timecounter *tc;
tc = (struct timecounter *)timecounter;
tv->tv_sec = tc->offset_sec;
count = tc->get_timedelta(tc);
delta = tc->offset_nano;
delta += ((u_int64_t)count * tc->scale_nano_f);
delta >>= 32;
delta += ((u_int64_t)count * tc->scale_nano_i);
delta += boottime.tv_usec * 1000;
tv->tv_sec += boottime.tv_sec;
while (delta >= 1000000000) {
delta -= 1000000000;
tv->tv_sec++;
}
tv->tv_nsec = delta;
}
void
getmicrouptime(struct timeval *tvp)
{
struct timecounter *tc;
tc = timecounter;
tvp->tv_sec = tc->offset_sec;
tvp->tv_usec = tc->offset_micro;
}
void
getnanouptime(struct timespec *tsp)
{
struct timecounter *tc;
tc = timecounter;
tsp->tv_sec = tc->offset_sec;
tsp->tv_nsec = tc->offset_nano >> 32;
}
void
microuptime(struct timeval *tv)
{
struct timecounter *tc;
tc = (struct timecounter *)timecounter;
tv->tv_sec = tc->offset_sec;
tv->tv_usec = tc->offset_micro;
tv->tv_usec +=
((u_int64_t)tc->get_timedelta(tc) * tc->scale_micro) >> 32;
if (tv->tv_usec >= 1000000) {
tv->tv_usec -= 1000000;
tv->tv_sec++;
}
}
void
nanouptime(struct timespec *tv)
{
u_int count;
u_int64_t delta;
struct timecounter *tc;
tc = (struct timecounter *)timecounter;
tv->tv_sec = tc->offset_sec;
count = tc->get_timedelta(tc);
delta = tc->offset_nano;
delta += ((u_int64_t)count * tc->scale_nano_f);
delta >>= 32;
delta += ((u_int64_t)count * tc->scale_nano_i);
if (delta >= 1000000000) {
delta -= 1000000000;
tv->tv_sec++;
}
tv->tv_nsec = delta;
}
static void
tco_setscales(struct timecounter *tc)
{
u_int64_t scale;
scale = 1000000000LL << 32;
if (tc->adjustment > 0)
scale += (tc->adjustment * 1000LL) << 10;
else
scale -= (-tc->adjustment * 1000LL) << 10;
scale /= tc->frequency;
tc->scale_micro = scale / 1000;
tc->scale_nano_f = scale & 0xffffffff;
tc->scale_nano_i = scale >> 32;
}
static u_int
delta_timecounter(struct timecounter *tc)
{
return((tc->get_timecount() - tc->offset_count) & tc->counter_mask);
}
void
init_timecounter(struct timecounter *tc)
{
struct timespec ts0, ts1;
int i;
if (!tc->get_timedelta)
tc->get_timedelta = delta_timecounter;
tc->adjustment = 0;
tco_setscales(tc);
tc->offset_count = tc->get_timecount();
tc[0].tweak = &tc[0];
tc[2] = tc[1] = tc[0];
tc[1].other = &tc[2];
tc[2].other = &tc[1];
if (!timecounter || !strcmp(timecounter->name, "dummy"))
timecounter = &tc[2];
tc = &tc[1];
/*
* Figure out the cost of calling this timecounter.
* XXX: The 1:15 ratio is a guess at reality.
*/
nanotime(&ts0);
for (i = 0; i < 16; i ++)
tc->get_timecount();
for (i = 0; i < 240; i ++)
tc->get_timedelta(tc);
nanotime(&ts1);
ts1.tv_sec -= ts0.tv_sec;
tc->cost = ts1.tv_sec * 1000000000 + ts1.tv_nsec - ts0.tv_nsec;
tc->cost >>= 8;
if (print_tci && strcmp(tc->name, "dummy"))
printf("Timecounter \"%s\" frequency %lu Hz cost %u ns\n",
tc->name, tc->frequency, tc->cost);
/* XXX: For now always start using the counter. */
tc->offset_count = tc->get_timecount();
nanotime(&ts1);
tc->offset_nano = (u_int64_t)ts1.tv_nsec << 32;
tc->offset_micro = ts1.tv_nsec / 1000;
tc->offset_sec = ts1.tv_sec;
timecounter = tc;
}
void
set_timecounter(struct timespec *ts)
{
struct timespec ts2;
nanouptime(&ts2);
boottime.tv_sec = ts->tv_sec - ts2.tv_sec;
boottime.tv_usec = (ts->tv_nsec - ts2.tv_nsec) / 1000;
if (boottime.tv_usec < 0) {
boottime.tv_usec += 1000000;
boottime.tv_sec--;
}
/* fiddle all the little crinkly bits around the fiords... */
tco_forward();
}
#if 0 /* Currently unused */
void
switch_timecounter(struct timecounter *newtc)
{
int s;
struct timecounter *tc;
struct timespec ts;
s = splclock();
tc = timecounter;
if (newtc == tc || newtc == tc->other) {
splx(s);
return;
}
nanotime(&ts);
newtc->offset_sec = ts.tv_sec;
newtc->offset_nano = (u_int64_t)ts.tv_nsec << 32;
newtc->offset_micro = ts.tv_nsec / 1000;
newtc->offset_count = newtc->get_timecount();
timecounter = newtc;
splx(s);
}
#endif
static struct timecounter *
sync_other_counter(void)
{
struct timecounter *tc, *tco;
u_int delta;
tc = timecounter->other;
tco = tc->other;
*tc = *timecounter;
tc->other = tco;
delta = tc->get_timedelta(tc);
tc->offset_count += delta;
tc->offset_count &= tc->counter_mask;
tc->offset_nano += (u_int64_t)delta * tc->scale_nano_f;
tc->offset_nano += (u_int64_t)delta * tc->scale_nano_i << 32;
return (tc);
}
static void
tco_forward(void)
{
struct timecounter *tc;
tc = sync_other_counter();
if (timedelta != 0) {
tc->offset_nano += (u_int64_t)(tickdelta * 1000) << 32;
timedelta -= tickdelta;
}
while (tc->offset_nano >= 1000000000ULL << 32) {
tc->offset_nano -= 1000000000ULL << 32;
tc->offset_sec++;
tc->frequency = tc->tweak->frequency;
tc->adjustment = tc->tweak->adjustment;
ntp_update_second(tc); /* XXX only needed if xntpd runs */
tco_setscales(tc);
}
tc->offset_micro = (tc->offset_nano / 1000) >> 32;
/* Figure out the wall-clock time */
tc->nanotime.tv_sec = tc->offset_sec + boottime.tv_sec;
tc->nanotime.tv_nsec = (tc->offset_nano >> 32) + boottime.tv_usec * 1000;
tc->microtime.tv_usec = tc->offset_micro + boottime.tv_usec;
if (tc->nanotime.tv_nsec >= 1000000000) {
tc->nanotime.tv_nsec -= 1000000000;
tc->microtime.tv_usec -= 1000000;
tc->nanotime.tv_sec++;
}
time_second = tc->microtime.tv_sec = tc->nanotime.tv_sec;
timecounter = tc;
}
static int
sysctl_kern_timecounter_frequency SYSCTL_HANDLER_ARGS
{
return (sysctl_handle_opaque(oidp, &timecounter->tweak->frequency,
sizeof(timecounter->tweak->frequency), req));
}
static int
sysctl_kern_timecounter_adjustment SYSCTL_HANDLER_ARGS
{
return (sysctl_handle_opaque(oidp, &timecounter->tweak->adjustment,
sizeof(timecounter->tweak->adjustment), req));
}
SYSCTL_NODE(_kern, OID_AUTO, timecounter, CTLFLAG_RW, 0, "");
SYSCTL_PROC(_kern_timecounter, OID_AUTO, frequency, CTLTYPE_INT | CTLFLAG_RW,
0, sizeof(u_int), sysctl_kern_timecounter_frequency, "I", "");
SYSCTL_PROC(_kern_timecounter, OID_AUTO, adjustment, CTLTYPE_INT | CTLFLAG_RW,
0, sizeof(int), sysctl_kern_timecounter_adjustment, "I", "");
/*
* Implement a dummy timecounter which we can use until we get a real one
* in the air. This allows the console and other early stuff to use
* timeservices.
*/
static u_int64_t
dummy_get_timecount(void)
{
static u_int64_t now;
return (++now);
}
static struct timecounter dummy_timecounter[3] = {
{
0,
dummy_get_timecount,
~0,
1000000,
"dummy"
}
};
static void
initdummytimecounter(void *dummy)
{
init_timecounter(dummy_timecounter);
}
SYSINIT(dummytc, SI_SUB_CONSOLE, SI_ORDER_FIRST, initdummytimecounter, NULL)
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