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NetBSD/sys/kern/kern_time.c

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/* $NetBSD: kern_time.c,v 1.155 2008/10/16 18:21:45 wrstuden Exp $ */
/*-
* Copyright (c) 2000, 2004, 2005, 2007, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christopher G. Demetriou.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* 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. 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_time.c 8.4 (Berkeley) 5/26/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_time.c,v 1.155 2008/10/16 18:21:45 wrstuden Exp $");
#include <sys/param.h>
#include <sys/resourcevar.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/signalvar.h>
#include <sys/syslog.h>
#include <sys/timetc.h>
#include <sys/timex.h>
#include <sys/kauth.h>
#include <sys/mount.h>
#include <sys/sa.h>
#include <sys/savar.h>
#include <sys/syscallargs.h>
#include <sys/cpu.h>
#include <uvm/uvm_extern.h>
#include "opt_sa.h"
static void timer_intr(void *);
static void itimerfire(struct ptimer *);
static void itimerfree(struct ptimers *, int);
kmutex_t timer_lock;
static void *timer_sih;
static TAILQ_HEAD(, ptimer) timer_queue;
POOL_INIT(ptimer_pool, sizeof(struct ptimer), 0, 0, 0, "ptimerpl",
&pool_allocator_nointr, IPL_NONE);
POOL_INIT(ptimers_pool, sizeof(struct ptimers), 0, 0, 0, "ptimerspl",
&pool_allocator_nointr, IPL_NONE);
/*
* Initialize timekeeping.
*/
void
time_init(void)
{
/* nothing yet */
}
void
time_init2(void)
{
TAILQ_INIT(&timer_queue);
mutex_init(&timer_lock, MUTEX_DEFAULT, IPL_SCHED);
timer_sih = softint_establish(SOFTINT_CLOCK | SOFTINT_MPSAFE,
timer_intr, NULL);
}
/* Time of day and interval timer support.
*
* These routines provide the kernel entry points to get and set
* the time-of-day and per-process interval timers. Subroutines
* here provide support for adding and subtracting timeval structures
* and decrementing interval timers, optionally reloading the interval
* timers when they expire.
*/
/* This function is used by clock_settime and settimeofday */
static int
settime1(struct proc *p, struct timespec *ts, bool check_kauth)
{
struct timeval delta, tv;
struct timeval now;
struct timespec ts1;
struct bintime btdelta;
lwp_t *l;
int s;
TIMESPEC_TO_TIMEVAL(&tv, ts);
/* WHAT DO WE DO ABOUT PENDING REAL-TIME TIMEOUTS??? */
s = splclock();
microtime(&now);
timersub(&tv, &now, &delta);
if (check_kauth && kauth_authorize_system(kauth_cred_get(),
KAUTH_SYSTEM_TIME, KAUTH_REQ_SYSTEM_TIME_SYSTEM, ts, &delta,
KAUTH_ARG(check_kauth ? false : true)) != 0) {
splx(s);
return (EPERM);
}
#ifdef notyet
if ((delta.tv_sec < 86400) && securelevel > 0) { /* XXX elad - notyet */
splx(s);
return (EPERM);
}
#endif
TIMEVAL_TO_TIMESPEC(&tv, &ts1);
tc_setclock(&ts1);
timeradd(&boottime, &delta, &boottime);
/*
* XXXSMP: There is a short race between setting the time above
* and adjusting LWP's run times. Fixing this properly means
* pausing all CPUs while we adjust the clock.
*/
timeval2bintime(&delta, &btdelta);
mutex_enter(proc_lock);
LIST_FOREACH(l, &alllwp, l_list) {
lwp_lock(l);
bintime_add(&l->l_stime, &btdelta);
lwp_unlock(l);
}
mutex_exit(proc_lock);
resettodr();
splx(s);
return (0);
}
int
settime(struct proc *p, struct timespec *ts)
{
return (settime1(p, ts, true));
}
/* ARGSUSED */
int
sys_clock_gettime(struct lwp *l, const struct sys_clock_gettime_args *uap,
register_t *retval)
{
/* {
syscallarg(clockid_t) clock_id;
syscallarg(struct timespec *) tp;
} */
clockid_t clock_id;
struct timespec ats;
clock_id = SCARG(uap, clock_id);
switch (clock_id) {
case CLOCK_REALTIME:
nanotime(&ats);
break;
case CLOCK_MONOTONIC:
nanouptime(&ats);
break;
default:
return (EINVAL);
}
return copyout(&ats, SCARG(uap, tp), sizeof(ats));
}
/* ARGSUSED */
int
sys_clock_settime(struct lwp *l, const struct sys_clock_settime_args *uap,
register_t *retval)
{
/* {
syscallarg(clockid_t) clock_id;
syscallarg(const struct timespec *) tp;
} */
return clock_settime1(l->l_proc, SCARG(uap, clock_id), SCARG(uap, tp),
true);
}
int
clock_settime1(struct proc *p, clockid_t clock_id, const struct timespec *tp,
bool check_kauth)
{
struct timespec ats;
int error;
if ((error = copyin(tp, &ats, sizeof(ats))) != 0)
return (error);
switch (clock_id) {
case CLOCK_REALTIME:
if ((error = settime1(p, &ats, check_kauth)) != 0)
return (error);
break;
case CLOCK_MONOTONIC:
return (EINVAL); /* read-only clock */
default:
return (EINVAL);
}
return 0;
}
int
sys_clock_getres(struct lwp *l, const struct sys_clock_getres_args *uap,
register_t *retval)
{
/* {
syscallarg(clockid_t) clock_id;
syscallarg(struct timespec *) tp;
} */
clockid_t clock_id;
struct timespec ts;
int error = 0;
clock_id = SCARG(uap, clock_id);
switch (clock_id) {
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
ts.tv_sec = 0;
if (tc_getfrequency() > 1000000000)
ts.tv_nsec = 1;
else
ts.tv_nsec = 1000000000 / tc_getfrequency();
break;
default:
return (EINVAL);
}
if (SCARG(uap, tp))
error = copyout(&ts, SCARG(uap, tp), sizeof(ts));
return error;
}
/* ARGSUSED */
int
sys_nanosleep(struct lwp *l, const struct sys_nanosleep_args *uap,
register_t *retval)
{
/* {
syscallarg(struct timespec *) rqtp;
syscallarg(struct timespec *) rmtp;
} */
struct timespec rmt, rqt;
int error, error1;
error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec));
if (error)
return (error);
error = nanosleep1(l, &rqt, SCARG(uap, rmtp) ? &rmt : NULL);
if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR))
return error;
error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt));
return error1 ? error1 : error;
}
int
nanosleep1(struct lwp *l, struct timespec *rqt, struct timespec *rmt)
{
struct timespec rmtstart;
int error, timo;
if (itimespecfix(rqt))
return (EINVAL);
timo = tstohz(rqt);
/*
* Avoid inadvertantly sleeping forever
*/
if (timo == 0)
timo = 1;
getnanouptime(&rmtstart);
again:
error = kpause("nanoslp", true, timo, NULL);
if (rmt != NULL || error == 0) {
struct timespec rmtend;
struct timespec t0;
struct timespec *t;
getnanouptime(&rmtend);
t = (rmt != NULL) ? rmt : &t0;
timespecsub(&rmtend, &rmtstart, t);
timespecsub(rqt, t, t);
if (t->tv_sec < 0)
timespecclear(t);
if (error == 0) {
timo = tstohz(t);
if (timo > 0)
goto again;
}
}
if (error == ERESTART)
error = EINTR;
if (error == EWOULDBLOCK)
error = 0;
return error;
}
/* ARGSUSED */
int
sys_gettimeofday(struct lwp *l, const struct sys_gettimeofday_args *uap,
register_t *retval)
{
/* {
syscallarg(struct timeval *) tp;
syscallarg(void *) tzp; really "struct timezone *";
} */
struct timeval atv;
int error = 0;
struct timezone tzfake;
if (SCARG(uap, tp)) {
microtime(&atv);
error = copyout(&atv, SCARG(uap, tp), sizeof(atv));
if (error)
return (error);
}
if (SCARG(uap, tzp)) {
/*
* NetBSD has no kernel notion of time zone, so we just
* fake up a timezone struct and return it if demanded.
*/
tzfake.tz_minuteswest = 0;
tzfake.tz_dsttime = 0;
error = copyout(&tzfake, SCARG(uap, tzp), sizeof(tzfake));
}
return (error);
}
/* ARGSUSED */
int
sys_settimeofday(struct lwp *l, const struct sys_settimeofday_args *uap,
register_t *retval)
{
/* {
syscallarg(const struct timeval *) tv;
syscallarg(const void *) tzp; really "const struct timezone *";
} */
return settimeofday1(SCARG(uap, tv), true, SCARG(uap, tzp), l, true);
}
int
settimeofday1(const struct timeval *utv, bool userspace,
const void *utzp, struct lwp *l, bool check_kauth)
{
struct timeval atv;
struct timespec ts;
int error;
/* Verify all parameters before changing time. */
/*
* NetBSD has no kernel notion of time zone, and only an
* obsolete program would try to set it, so we log a warning.
*/
if (utzp)
log(LOG_WARNING, "pid %d attempted to set the "
"(obsolete) kernel time zone\n", l->l_proc->p_pid);
if (utv == NULL)
return 0;
if (userspace) {
if ((error = copyin(utv, &atv, sizeof(atv))) != 0)
return error;
utv = &atv;
}
TIMEVAL_TO_TIMESPEC(utv, &ts);
return settime1(l->l_proc, &ts, check_kauth);
}
int time_adjusted; /* set if an adjustment is made */
/* ARGSUSED */
int
sys_adjtime(struct lwp *l, const struct sys_adjtime_args *uap,
register_t *retval)
{
/* {
syscallarg(const struct timeval *) delta;
syscallarg(struct timeval *) olddelta;
} */
int error;
if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_TIME,
KAUTH_REQ_SYSTEM_TIME_ADJTIME, NULL, NULL, NULL)) != 0)
return (error);
return adjtime1(SCARG(uap, delta), SCARG(uap, olddelta), l->l_proc);
}
int
adjtime1(const struct timeval *delta, struct timeval *olddelta, struct proc *p)
{
struct timeval atv;
int error = 0;
extern int64_t time_adjtime; /* in kern_ntptime.c */
if (olddelta) {
mutex_spin_enter(&timecounter_lock);
atv.tv_sec = time_adjtime / 1000000;
atv.tv_usec = time_adjtime % 1000000;
mutex_spin_exit(&timecounter_lock);
if (atv.tv_usec < 0) {
atv.tv_usec += 1000000;
atv.tv_sec--;
}
error = copyout(&atv, olddelta, sizeof(struct timeval));
if (error)
return (error);
}
if (delta) {
error = copyin(delta, &atv, sizeof(struct timeval));
if (error)
return (error);
mutex_spin_enter(&timecounter_lock);
time_adjtime = (int64_t)atv.tv_sec * 1000000 +
atv.tv_usec;
if (time_adjtime) {
/* We need to save the system time during shutdown */
time_adjusted |= 1;
}
mutex_spin_exit(&timecounter_lock);
}
return error;
}
/*
* Interval timer support. Both the BSD getitimer() family and the POSIX
* timer_*() family of routines are supported.
*
* All timers are kept in an array pointed to by p_timers, which is
* allocated on demand - many processes don't use timers at all. The
* first three elements in this array are reserved for the BSD timers:
* element 0 is ITIMER_REAL, element 1 is ITIMER_VIRTUAL, and element
* 2 is ITIMER_PROF. The rest may be allocated by the timer_create()
* syscall.
*
* Realtime timers are kept in the ptimer structure as an absolute
* time; virtual time timers are kept as a linked list of deltas.
* Virtual time timers are processed in the hardclock() routine of
* kern_clock.c. The real time timer is processed by a callout
* routine, called from the softclock() routine. Since a callout may
* be delayed in real time due to interrupt processing in the system,
* it is possible for the real time timeout routine (realtimeexpire,
* given below), to be delayed in real time past when it is supposed
* to occur. It does not suffice, therefore, to reload the real timer
* .it_value from the real time timers .it_interval. Rather, we
* compute the next time in absolute time the timer should go off. */
/* Allocate a POSIX realtime timer. */
int
sys_timer_create(struct lwp *l, const struct sys_timer_create_args *uap,
register_t *retval)
{
/* {
syscallarg(clockid_t) clock_id;
syscallarg(struct sigevent *) evp;
syscallarg(timer_t *) timerid;
} */
return timer_create1(SCARG(uap, timerid), SCARG(uap, clock_id),
SCARG(uap, evp), copyin, l);
}
int
timer_create1(timer_t *tid, clockid_t id, struct sigevent *evp,
copyin_t fetch_event, struct lwp *l)
{
int error;
timer_t timerid;
struct ptimers *pts;
struct ptimer *pt;
struct proc *p;
p = l->l_proc;
if (id < CLOCK_REALTIME || id > CLOCK_PROF)
return (EINVAL);
if ((pts = p->p_timers) == NULL)
pts = timers_alloc(p);
pt = pool_get(&ptimer_pool, PR_WAITOK);
if (evp != NULL) {
if (((error =
(*fetch_event)(evp, &pt->pt_ev, sizeof(pt->pt_ev))) != 0) ||
((pt->pt_ev.sigev_notify < SIGEV_NONE) ||
(pt->pt_ev.sigev_notify > SIGEV_SA))) {
pool_put(&ptimer_pool, pt);
return (error ? error : EINVAL);
}
}
/* Find a free timer slot, skipping those reserved for setitimer(). */
mutex_spin_enter(&timer_lock);
for (timerid = 3; timerid < TIMER_MAX; timerid++)
if (pts->pts_timers[timerid] == NULL)
break;
if (timerid == TIMER_MAX) {
mutex_spin_exit(&timer_lock);
pool_put(&ptimer_pool, pt);
return EAGAIN;
}
if (evp == NULL) {
pt->pt_ev.sigev_notify = SIGEV_SIGNAL;
switch (id) {
case CLOCK_REALTIME:
pt->pt_ev.sigev_signo = SIGALRM;
break;
case CLOCK_VIRTUAL:
pt->pt_ev.sigev_signo = SIGVTALRM;
break;
case CLOCK_PROF:
pt->pt_ev.sigev_signo = SIGPROF;
break;
}
pt->pt_ev.sigev_value.sival_int = timerid;
}
pt->pt_info.ksi_signo = pt->pt_ev.sigev_signo;
pt->pt_info.ksi_errno = 0;
pt->pt_info.ksi_code = 0;
pt->pt_info.ksi_pid = p->p_pid;
pt->pt_info.ksi_uid = kauth_cred_getuid(l->l_cred);
pt->pt_info.ksi_value = pt->pt_ev.sigev_value;
pt->pt_type = id;
pt->pt_proc = p;
pt->pt_overruns = 0;
pt->pt_poverruns = 0;
pt->pt_entry = timerid;
pt->pt_queued = false;
timespecclear(&pt->pt_time.it_value);
if (id == CLOCK_REALTIME)
callout_init(&pt->pt_ch, 0);
else
pt->pt_active = 0;
pts->pts_timers[timerid] = pt;
mutex_spin_exit(&timer_lock);
return copyout(&timerid, tid, sizeof(timerid));
}
/* Delete a POSIX realtime timer */
int
sys_timer_delete(struct lwp *l, const struct sys_timer_delete_args *uap,
register_t *retval)
{
/* {
syscallarg(timer_t) timerid;
} */
struct proc *p = l->l_proc;
timer_t timerid;
struct ptimers *pts;
struct ptimer *pt, *ptn;
timerid = SCARG(uap, timerid);
pts = p->p_timers;
if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
return (EINVAL);
mutex_spin_enter(&timer_lock);
if ((pt = pts->pts_timers[timerid]) == NULL) {
mutex_spin_exit(&timer_lock);
return (EINVAL);
}
if (pt->pt_type != CLOCK_REALTIME) {
if (pt->pt_active) {
ptn = LIST_NEXT(pt, pt_list);
LIST_REMOVE(pt, pt_list);
for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list))
timespecadd(&pt->pt_time.it_value,
&ptn->pt_time.it_value,
&ptn->pt_time.it_value);
pt->pt_active = 0;
}
}
itimerfree(pts, timerid);
return (0);
}
/*
* Set up the given timer. The value in pt->pt_time.it_value is taken
* to be an absolute time for CLOCK_REALTIME timers and a relative
* time for virtual timers.
* Must be called at splclock().
*/
void
timer_settime(struct ptimer *pt)
{
struct ptimer *ptn, *pptn;
struct ptlist *ptl;
KASSERT(mutex_owned(&timer_lock));
if (pt->pt_type == CLOCK_REALTIME) {
callout_stop(&pt->pt_ch);
if (timespecisset(&pt->pt_time.it_value)) {
/*
* Don't need to check tshzto() return value, here.
* callout_reset() does it for us.
*/
callout_reset(&pt->pt_ch, tshzto(&pt->pt_time.it_value),
realtimerexpire, pt);
}
} else {
if (pt->pt_active) {
ptn = LIST_NEXT(pt, pt_list);
LIST_REMOVE(pt, pt_list);
for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list))
timespecadd(&pt->pt_time.it_value,
&ptn->pt_time.it_value,
&ptn->pt_time.it_value);
}
if (timespecisset(&pt->pt_time.it_value)) {
if (pt->pt_type == CLOCK_VIRTUAL)
ptl = &pt->pt_proc->p_timers->pts_virtual;
else
ptl = &pt->pt_proc->p_timers->pts_prof;
for (ptn = LIST_FIRST(ptl), pptn = NULL;
ptn && timespeccmp(&pt->pt_time.it_value,
&ptn->pt_time.it_value, >);
pptn = ptn, ptn = LIST_NEXT(ptn, pt_list))
timespecsub(&pt->pt_time.it_value,
&ptn->pt_time.it_value,
&pt->pt_time.it_value);
if (pptn)
LIST_INSERT_AFTER(pptn, pt, pt_list);
else
LIST_INSERT_HEAD(ptl, pt, pt_list);
for ( ; ptn ; ptn = LIST_NEXT(ptn, pt_list))
timespecsub(&ptn->pt_time.it_value,
&pt->pt_time.it_value,
&ptn->pt_time.it_value);
pt->pt_active = 1;
} else
pt->pt_active = 0;
}
}
void
timer_gettime(struct ptimer *pt, struct itimerspec *aits)
{
struct timespec now;
struct ptimer *ptn;
KASSERT(mutex_owned(&timer_lock));
*aits = pt->pt_time;
if (pt->pt_type == CLOCK_REALTIME) {
/*
* Convert from absolute to relative time in .it_value
* part of real time timer. If time for real time
* timer has passed return 0, else return difference
* between current time and time for the timer to go
* off.
*/
if (timespecisset(&aits->it_value)) {
getnanotime(&now);
if (timespeccmp(&aits->it_value, &now, <))
timespecclear(&aits->it_value);
else
timespecsub(&aits->it_value, &now,
&aits->it_value);
}
} else if (pt->pt_active) {
if (pt->pt_type == CLOCK_VIRTUAL)
ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_virtual);
else
ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_prof);
for ( ; ptn && ptn != pt; ptn = LIST_NEXT(ptn, pt_list))
timespecadd(&aits->it_value,
&ptn->pt_time.it_value, &aits->it_value);
KASSERT(ptn != NULL); /* pt should be findable on the list */
} else
timespecclear(&aits->it_value);
}
/* Set and arm a POSIX realtime timer */
int
sys_timer_settime(struct lwp *l, const struct sys_timer_settime_args *uap,
register_t *retval)
{
/* {
syscallarg(timer_t) timerid;
syscallarg(int) flags;
syscallarg(const struct itimerspec *) value;
syscallarg(struct itimerspec *) ovalue;
} */
int error;
struct itimerspec value, ovalue, *ovp = NULL;
if ((error = copyin(SCARG(uap, value), &value,
sizeof(struct itimerspec))) != 0)
return (error);
if (SCARG(uap, ovalue))
ovp = &ovalue;
if ((error = dotimer_settime(SCARG(uap, timerid), &value, ovp,
SCARG(uap, flags), l->l_proc)) != 0)
return error;
if (ovp)
return copyout(&ovalue, SCARG(uap, ovalue),
sizeof(struct itimerspec));
return 0;
}
int
dotimer_settime(int timerid, struct itimerspec *value,
struct itimerspec *ovalue, int flags, struct proc *p)
{
struct timespec now;
struct itimerspec val, oval;
struct ptimers *pts;
struct ptimer *pt;
pts = p->p_timers;
if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
return EINVAL;
val = *value;
if (itimespecfix(&val.it_value) || itimespecfix(&val.it_interval))
return EINVAL;
mutex_spin_enter(&timer_lock);
if ((pt = pts->pts_timers[timerid]) == NULL) {
mutex_spin_exit(&timer_lock);
return EINVAL;
}
oval = pt->pt_time;
pt->pt_time = val;
/*
* If we've been passed a relative time for a realtime timer,
* convert it to absolute; if an absolute time for a virtual
* timer, convert it to relative and make sure we don't set it
* to zero, which would cancel the timer, or let it go
* negative, which would confuse the comparison tests.
*/
if (timespecisset(&pt->pt_time.it_value)) {
if (pt->pt_type == CLOCK_REALTIME) {
if ((flags & TIMER_ABSTIME) == 0) {
getnanotime(&now);
timespecadd(&pt->pt_time.it_value, &now,
&pt->pt_time.it_value);
}
} else {
if ((flags & TIMER_ABSTIME) != 0) {
getnanotime(&now);
timespecsub(&pt->pt_time.it_value, &now,
&pt->pt_time.it_value);
if (!timespecisset(&pt->pt_time.it_value) ||
pt->pt_time.it_value.tv_sec < 0) {
pt->pt_time.it_value.tv_sec = 0;
pt->pt_time.it_value.tv_nsec = 1;
}
}
}
}
timer_settime(pt);
mutex_spin_exit(&timer_lock);
if (ovalue)
*ovalue = oval;
return (0);
}
/* Return the time remaining until a POSIX timer fires. */
int
sys_timer_gettime(struct lwp *l, const struct sys_timer_gettime_args *uap,
register_t *retval)
{
/* {
syscallarg(timer_t) timerid;
syscallarg(struct itimerspec *) value;
} */
struct itimerspec its;
int error;
if ((error = dotimer_gettime(SCARG(uap, timerid), l->l_proc,
&its)) != 0)
return error;
return copyout(&its, SCARG(uap, value), sizeof(its));
}
int
dotimer_gettime(int timerid, struct proc *p, struct itimerspec *its)
{
struct ptimer *pt;
struct ptimers *pts;
pts = p->p_timers;
if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
return (EINVAL);
mutex_spin_enter(&timer_lock);
if ((pt = pts->pts_timers[timerid]) == NULL) {
mutex_spin_exit(&timer_lock);
return (EINVAL);
}
timer_gettime(pt, its);
mutex_spin_exit(&timer_lock);
return 0;
}
/*
* Return the count of the number of times a periodic timer expired
* while a notification was already pending. The counter is reset when
* a timer expires and a notification can be posted.
*/
int
sys_timer_getoverrun(struct lwp *l, const struct sys_timer_getoverrun_args *uap,
register_t *retval)
{
/* {
syscallarg(timer_t) timerid;
} */
struct proc *p = l->l_proc;
struct ptimers *pts;
int timerid;
struct ptimer *pt;
timerid = SCARG(uap, timerid);
pts = p->p_timers;
if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
return (EINVAL);
mutex_spin_enter(&timer_lock);
if ((pt = pts->pts_timers[timerid]) == NULL) {
mutex_spin_exit(&timer_lock);
return (EINVAL);
}
*retval = pt->pt_poverruns;
mutex_spin_exit(&timer_lock);
return (0);
}
#ifdef KERN_SA
/* Glue function that triggers an upcall; called from userret(). */
void
timerupcall(struct lwp *l)
{
struct ptimers *pt = l->l_proc->p_timers;
struct proc *p = l->l_proc;
unsigned int i, fired, done;
KDASSERT(l->l_proc->p_sa);
/* Bail out if we do not own the virtual processor */
if (l->l_savp->savp_lwp != l)
return ;
mutex_enter(p->p_lock);
fired = pt->pts_fired;
done = 0;
while ((i = ffs(fired)) != 0) {
siginfo_t *si;
int mask = 1 << --i;
int f;
f = ~l->l_pflag & LP_SA_NOBLOCK;
l->l_pflag |= LP_SA_NOBLOCK;
si = siginfo_alloc(PR_WAITOK);
si->_info = pt->pts_timers[i]->pt_info.ksi_info;
if (sa_upcall(l, SA_UPCALL_SIGEV | SA_UPCALL_DEFER, NULL, l,
sizeof(*si), si, siginfo_free) != 0) {
siginfo_free(si);
/* XXX What do we do here?? */
} else
done |= mask;
fired &= ~mask;
l->l_pflag ^= f;
}
pt->pts_fired &= ~done;
if (pt->pts_fired == 0)
l->l_proc->p_timerpend = 0;
mutex_exit(p->p_lock);
}
#endif /* KERN_SA */
/*
* Real interval timer expired:
* send process whose timer expired an alarm signal.
* If time is not set up to reload, then just return.
* Else compute next time timer should go off which is > current time.
* This is where delay in processing this timeout causes multiple
* SIGALRM calls to be compressed into one.
*/
void
realtimerexpire(void *arg)
{
uint64_t last_val, next_val, interval, now_ms;
struct timespec now, next;
struct ptimer *pt;
int backwards;
pt = arg;
mutex_spin_enter(&timer_lock);
itimerfire(pt);
if (!timespecisset(&pt->pt_time.it_interval)) {
timespecclear(&pt->pt_time.it_value);
mutex_spin_exit(&timer_lock);
return;
}
getnanotime(&now);
backwards = (timespeccmp(&pt->pt_time.it_value, &now, >));
timespecadd(&pt->pt_time.it_value, &pt->pt_time.it_interval, &next);
/* Handle the easy case of non-overflown timers first. */
if (!backwards && timespeccmp(&next, &now, >)) {
pt->pt_time.it_value = next;
} else {
now_ms = timespec2ns(&now);
last_val = timespec2ns(&pt->pt_time.it_value);
interval = timespec2ns(&pt->pt_time.it_interval);
next_val = now_ms +
(now_ms - last_val + interval - 1) % interval;
if (backwards)
next_val += interval;
else
pt->pt_overruns += (now_ms - last_val) / interval;
pt->pt_time.it_value.tv_sec = next_val / 1000000000;
pt->pt_time.it_value.tv_nsec = next_val % 1000000000;
}
/*
* Don't need to check tshzto() return value, here.
* callout_reset() does it for us.
*/
callout_reset(&pt->pt_ch, tshzto(&pt->pt_time.it_value),
realtimerexpire, pt);
mutex_spin_exit(&timer_lock);
}
/* BSD routine to get the value of an interval timer. */
/* ARGSUSED */
int
sys_getitimer(struct lwp *l, const struct sys_getitimer_args *uap,
register_t *retval)
{
/* {
syscallarg(int) which;
syscallarg(struct itimerval *) itv;
} */
struct proc *p = l->l_proc;
struct itimerval aitv;
int error;
error = dogetitimer(p, SCARG(uap, which), &aitv);
if (error)
return error;
return (copyout(&aitv, SCARG(uap, itv), sizeof(struct itimerval)));
}
int
dogetitimer(struct proc *p, int which, struct itimerval *itvp)
{
struct ptimers *pts;
struct ptimer *pt;
struct itimerspec its;
if ((u_int)which > ITIMER_PROF)
return (EINVAL);
mutex_spin_enter(&timer_lock);
pts = p->p_timers;
if (pts == NULL || (pt = pts->pts_timers[which]) == NULL) {
timerclear(&itvp->it_value);
timerclear(&itvp->it_interval);
} else {
timer_gettime(pt, &its);
TIMESPEC_TO_TIMEVAL(&itvp->it_value, &its.it_value);
TIMESPEC_TO_TIMEVAL(&itvp->it_interval, &its.it_interval);
}
mutex_spin_exit(&timer_lock);
return 0;
}
/* BSD routine to set/arm an interval timer. */
/* ARGSUSED */
int
sys_setitimer(struct lwp *l, const struct sys_setitimer_args *uap,
register_t *retval)
{
/* {
syscallarg(int) which;
syscallarg(const struct itimerval *) itv;
syscallarg(struct itimerval *) oitv;
} */
struct proc *p = l->l_proc;
int which = SCARG(uap, which);
struct sys_getitimer_args getargs;
const struct itimerval *itvp;
struct itimerval aitv;
int error;
if ((u_int)which > ITIMER_PROF)
return (EINVAL);
itvp = SCARG(uap, itv);
if (itvp &&
(error = copyin(itvp, &aitv, sizeof(struct itimerval)) != 0))
return (error);
if (SCARG(uap, oitv) != NULL) {
SCARG(&getargs, which) = which;
SCARG(&getargs, itv) = SCARG(uap, oitv);
if ((error = sys_getitimer(l, &getargs, retval)) != 0)
return (error);
}
if (itvp == 0)
return (0);
return dosetitimer(p, which, &aitv);
}
int
dosetitimer(struct proc *p, int which, struct itimerval *itvp)
{
struct timespec now;
struct ptimers *pts;
struct ptimer *pt, *spare;
if (itimerfix(&itvp->it_value) || itimerfix(&itvp->it_interval))
return (EINVAL);
/*
* Don't bother allocating data structures if the process just
* wants to clear the timer.
*/
spare = NULL;
pts = p->p_timers;
retry:
if (!timerisset(&itvp->it_value) && (pts == NULL ||
pts->pts_timers[which] == NULL))
return (0);
if (pts == NULL)
pts = timers_alloc(p);
mutex_spin_enter(&timer_lock);
pt = pts->pts_timers[which];
if (pt == NULL) {
if (spare == NULL) {
mutex_spin_exit(&timer_lock);
spare = pool_get(&ptimer_pool, PR_WAITOK);
goto retry;
}
pt = spare;
spare = NULL;
pt->pt_ev.sigev_notify = SIGEV_SIGNAL;
pt->pt_ev.sigev_value.sival_int = which;
pt->pt_overruns = 0;
pt->pt_proc = p;
pt->pt_type = which;
pt->pt_entry = which;
pt->pt_queued = false;
if (pt->pt_type == CLOCK_REALTIME)
callout_init(&pt->pt_ch, CALLOUT_MPSAFE);
else
pt->pt_active = 0;
switch (which) {
case ITIMER_REAL:
pt->pt_ev.sigev_signo = SIGALRM;
break;
case ITIMER_VIRTUAL:
pt->pt_ev.sigev_signo = SIGVTALRM;
break;
case ITIMER_PROF:
pt->pt_ev.sigev_signo = SIGPROF;
break;
}
pts->pts_timers[which] = pt;
}
TIMEVAL_TO_TIMESPEC(&itvp->it_value, &pt->pt_time.it_value);
TIMEVAL_TO_TIMESPEC(&itvp->it_interval, &pt->pt_time.it_interval);
if ((which == ITIMER_REAL) && timespecisset(&pt->pt_time.it_value)) {
/* Convert to absolute time */
/* XXX need to wrap in splclock for timecounters case? */
getnanotime(&now);
timespecadd(&pt->pt_time.it_value, &now, &pt->pt_time.it_value);
}
timer_settime(pt);
mutex_spin_exit(&timer_lock);
if (spare != NULL)
pool_put(&ptimer_pool, spare);
return (0);
}
/* Utility routines to manage the array of pointers to timers. */
struct ptimers *
timers_alloc(struct proc *p)
{
struct ptimers *pts;
int i;
pts = pool_get(&ptimers_pool, PR_WAITOK);
LIST_INIT(&pts->pts_virtual);
LIST_INIT(&pts->pts_prof);
for (i = 0; i < TIMER_MAX; i++)
pts->pts_timers[i] = NULL;
pts->pts_fired = 0;
mutex_spin_enter(&timer_lock);
if (p->p_timers == NULL) {
p->p_timers = pts;
mutex_spin_exit(&timer_lock);
return pts;
}
mutex_spin_exit(&timer_lock);
pool_put(&ptimers_pool, pts);
return p->p_timers;
}
/*
* Clean up the per-process timers. If "which" is set to TIMERS_ALL,
* then clean up all timers and free all the data structures. If
* "which" is set to TIMERS_POSIX, only clean up the timers allocated
* by timer_create(), not the BSD setitimer() timers, and only free the
* structure if none of those remain.
*/
void
timers_free(struct proc *p, int which)
{
struct ptimers *pts;
struct ptimer *ptn;
struct timespec ts;
int i;
if (p->p_timers == NULL)
return;
pts = p->p_timers;
mutex_spin_enter(&timer_lock);
if (which == TIMERS_ALL) {
p->p_timers = NULL;
i = 0;
} else {
timespecclear(&ts);
for (ptn = LIST_FIRST(&pts->pts_virtual);
ptn && ptn != pts->pts_timers[ITIMER_VIRTUAL];
ptn = LIST_NEXT(ptn, pt_list)) {
KASSERT(ptn->pt_type != CLOCK_REALTIME);
timespecadd(&ts, &ptn->pt_time.it_value, &ts);
}
LIST_FIRST(&pts->pts_virtual) = NULL;
if (ptn) {
KASSERT(ptn->pt_type != CLOCK_REALTIME);
timespecadd(&ts, &ptn->pt_time.it_value,
&ptn->pt_time.it_value);
LIST_INSERT_HEAD(&pts->pts_virtual, ptn, pt_list);
}
timespecclear(&ts);
for (ptn = LIST_FIRST(&pts->pts_prof);
ptn && ptn != pts->pts_timers[ITIMER_PROF];
ptn = LIST_NEXT(ptn, pt_list)) {
KASSERT(ptn->pt_type != CLOCK_REALTIME);
timespecadd(&ts, &ptn->pt_time.it_value, &ts);
}
LIST_FIRST(&pts->pts_prof) = NULL;
if (ptn) {
KASSERT(ptn->pt_type != CLOCK_REALTIME);
timespecadd(&ts, &ptn->pt_time.it_value,
&ptn->pt_time.it_value);
LIST_INSERT_HEAD(&pts->pts_prof, ptn, pt_list);
}
i = 3;
}
for ( ; i < TIMER_MAX; i++) {
if (pts->pts_timers[i] != NULL) {
itimerfree(pts, i);
mutex_spin_enter(&timer_lock);
}
}
if (pts->pts_timers[0] == NULL && pts->pts_timers[1] == NULL &&
pts->pts_timers[2] == NULL) {
p->p_timers = NULL;
mutex_spin_exit(&timer_lock);
pool_put(&ptimers_pool, pts);
} else
mutex_spin_exit(&timer_lock);
}
static void
itimerfree(struct ptimers *pts, int index)
{
struct ptimer *pt;
KASSERT(mutex_owned(&timer_lock));
pt = pts->pts_timers[index];
pts->pts_timers[index] = NULL;
if (pt->pt_type == CLOCK_REALTIME)
callout_halt(&pt->pt_ch, &timer_lock);
else if (pt->pt_queued)
TAILQ_REMOVE(&timer_queue, pt, pt_chain);
mutex_spin_exit(&timer_lock);
if (pt->pt_type == CLOCK_REALTIME)
callout_destroy(&pt->pt_ch);
pool_put(&ptimer_pool, pt);
}
/*
* Decrement an interval timer by a specified number
* of nanoseconds, which must be less than a second,
* i.e. < 1000000000. If the timer expires, then reload
* it. In this case, carry over (nsec - old value) to
* reduce the value reloaded into the timer so that
* the timer does not drift. This routine assumes
* that it is called in a context where the timers
* on which it is operating cannot change in value.
*/
static int
itimerdecr(struct ptimer *pt, int nsec)
{
struct itimerspec *itp;
KASSERT(mutex_owned(&timer_lock));
itp = &pt->pt_time;
if (itp->it_value.tv_nsec < nsec) {
if (itp->it_value.tv_sec == 0) {
/* expired, and already in next interval */
nsec -= itp->it_value.tv_nsec;
goto expire;
}
itp->it_value.tv_nsec += 1000000000;
itp->it_value.tv_sec--;
}
itp->it_value.tv_nsec -= nsec;
nsec = 0;
if (timespecisset(&itp->it_value))
return (1);
/* expired, exactly at end of interval */
expire:
if (timespecisset(&itp->it_interval)) {
itp->it_value = itp->it_interval;
itp->it_value.tv_nsec -= nsec;
if (itp->it_value.tv_nsec < 0) {
itp->it_value.tv_nsec += 1000000000;
itp->it_value.tv_sec--;
}
timer_settime(pt);
} else
itp->it_value.tv_nsec = 0; /* sec is already 0 */
return (0);
}
static void
itimerfire(struct ptimer *pt)
{
KASSERT(mutex_owned(&timer_lock));
/*
* XXX Can overrun, but we don't do signal queueing yet, anyway.
* XXX Relying on the clock interrupt is stupid.
*/
if ((pt->pt_ev.sigev_notify == SIGEV_SA && pt->pt_proc->p_sa == NULL) ||
(pt->pt_ev.sigev_notify != SIGEV_SIGNAL &&
pt->pt_ev.sigev_notify != SIGEV_SA) || pt->pt_queued)
return;
TAILQ_INSERT_TAIL(&timer_queue, pt, pt_chain);
pt->pt_queued = true;
softint_schedule(timer_sih);
}
void
timer_tick(lwp_t *l, bool user)
{
struct ptimers *pts;
struct ptimer *pt;
proc_t *p;
p = l->l_proc;
if (p->p_timers == NULL)
return;
mutex_spin_enter(&timer_lock);
if ((pts = l->l_proc->p_timers) != NULL) {
/*
* Run current process's virtual and profile time, as needed.
*/
if (user && (pt = LIST_FIRST(&pts->pts_virtual)) != NULL)
if (itimerdecr(pt, tick * 1000) == 0)
itimerfire(pt);
if ((pt = LIST_FIRST(&pts->pts_prof)) != NULL)
if (itimerdecr(pt, tick * 1000) == 0)
itimerfire(pt);
}
mutex_spin_exit(&timer_lock);
}
#ifdef KERN_SA
/*
* timer_sa_intr:
*
* SIGEV_SA handling for timer_intr(). We are called (and return)
* with the timer lock held. We know that the process had SA enabled
* when this timer was enqueued. As timer_intr() is a soft interrupt
* handler, SA should still be enabled by the time we get here.
*/
static void
timer_sa_intr(struct ptimer *pt, proc_t *p)
{
unsigned int i;
struct sadata *sa;
struct sadata_vp *vp;
/* Cause the process to generate an upcall when it returns. */
if (!p->p_timerpend) {
/*
* XXX stop signals can be processed inside tsleep,
* which can be inside sa_yield's inner loop, which
* makes testing for sa_idle alone insuffucent to
* determine if we really should call setrunnable.
*/
pt->pt_poverruns = pt->pt_overruns;
pt->pt_overruns = 0;
i = 1 << pt->pt_entry;
p->p_timers->pts_fired = i;
p->p_timerpend = 1;
sa = p->p_sa;
mutex_enter(&sa->sa_mutex);
SLIST_FOREACH(vp, &sa->sa_vps, savp_next) {
struct lwp *vp_lwp = vp->savp_lwp;
lwp_lock(vp_lwp);
lwp_need_userret(vp_lwp);
if (vp_lwp->l_flag & LW_SA_IDLE) {
vp_lwp->l_flag &= ~LW_SA_IDLE;
lwp_unsleep(vp_lwp, true);
break;
}
lwp_unlock(vp_lwp);
}
mutex_exit(&sa->sa_mutex);
} else {
i = 1 << pt->pt_entry;
if ((p->p_timers->pts_fired & i) == 0) {
pt->pt_poverruns = pt->pt_overruns;
pt->pt_overruns = 0;
p->p_timers->pts_fired |= i;
} else
pt->pt_overruns++;
}
}
#endif /* KERN_SA */
static void
timer_intr(void *cookie)
{
ksiginfo_t ksi;
struct ptimer *pt;
proc_t *p;
mutex_spin_enter(&timer_lock);
while ((pt = TAILQ_FIRST(&timer_queue)) != NULL) {
TAILQ_REMOVE(&timer_queue, pt, pt_chain);
KASSERT(pt->pt_queued);
pt->pt_queued = false;
if (pt->pt_proc->p_timers == NULL) {
/* Process is dying. */
continue;
}
p = pt->pt_proc;
#ifdef KERN_SA
if (pt->pt_ev.sigev_notify == SIGEV_SA) {
timer_sa_intr(pt, p);
continue;
}
#endif /* KERN_SA */
if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL)
continue;
if (sigismember(&p->p_sigpend.sp_set, pt->pt_ev.sigev_signo)) {
pt->pt_overruns++;
continue;
}
KSI_INIT(&ksi);
ksi.ksi_signo = pt->pt_ev.sigev_signo;
ksi.ksi_code = SI_TIMER;
ksi.ksi_value = pt->pt_ev.sigev_value;
pt->pt_poverruns = pt->pt_overruns;
pt->pt_overruns = 0;
mutex_spin_exit(&timer_lock);
mutex_enter(proc_lock);
kpsignal(p, &ksi, NULL);
mutex_exit(proc_lock);
mutex_spin_enter(&timer_lock);
}
mutex_spin_exit(&timer_lock);
}
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