freebsd-dev/sys/kern/kern_time.c

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/*-
1994-05-24 10:09:53 +00:00
* 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.
* 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_time.c 8.1 (Berkeley) 6/10/93
*/
2003-06-11 00:56:59 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
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#include <sys/param.h>
#include <sys/systm.h>
#include <sys/limits.h>
#include <sys/clock.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/sysproto.h>
#include <sys/eventhandler.h>
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#include <sys/resourcevar.h>
#include <sys/signalvar.h>
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#include <sys/kernel.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#include <sys/sysent.h>
#include <sys/priv.h>
1994-05-24 10:09:53 +00:00
#include <sys/proc.h>
#include <sys/posix4.h>
#include <sys/time.h>
#include <sys/timers.h>
#include <sys/timetc.h>
1994-05-24 10:09:53 +00:00
#include <sys/vnode.h>
#include <vm/vm.h>
#include <vm/vm_extern.h>
1994-05-24 10:09:53 +00:00
#define MAX_CLOCKS (CLOCK_MONOTONIC+1)
static struct kclock posix_clocks[MAX_CLOCKS];
static uma_zone_t itimer_zone = NULL;
1995-05-30 08:16:23 +00:00
/*
1994-05-24 10:09:53 +00:00
* 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.
*/
static int settime(struct thread *, struct timeval *);
2002-03-19 21:25:46 +00:00
static void timevalfix(struct timeval *);
static void no_lease_updatetime(int);
static void itimer_start(void);
static int itimer_init(void *, int, int);
static void itimer_fini(void *, int);
static void itimer_enter(struct itimer *);
static void itimer_leave(struct itimer *);
static struct itimer *itimer_find(struct proc *, int);
static void itimers_alloc(struct proc *);
static void itimers_event_hook_exec(void *arg, struct proc *p, struct image_params *imgp);
static void itimers_event_hook_exit(void *arg, struct proc *p);
static int realtimer_create(struct itimer *);
static int realtimer_gettime(struct itimer *, struct itimerspec *);
static int realtimer_settime(struct itimer *, int,
struct itimerspec *, struct itimerspec *);
static int realtimer_delete(struct itimer *);
static void realtimer_clocktime(clockid_t, struct timespec *);
static void realtimer_expire(void *);
static int kern_timer_create(struct thread *, clockid_t,
struct sigevent *, int *, int);
static int kern_timer_delete(struct thread *, int);
int register_posix_clock(int, struct kclock *);
void itimer_fire(struct itimer *it);
int itimespecfix(struct timespec *ts);
#define CLOCK_CALL(clock, call, arglist) \
((*posix_clocks[clock].call) arglist)
SYSINIT(posix_timer, SI_SUB_P1003_1B, SI_ORDER_FIRST+4, itimer_start, NULL);
1997-10-26 20:26:33 +00:00
static void
no_lease_updatetime(deltat)
int deltat;
{
}
2002-03-19 21:25:46 +00:00
void (*lease_updatetime)(int) = no_lease_updatetime;
1997-10-26 20:26:33 +00:00
static int
settime(struct thread *td, struct timeval *tv)
{
struct timeval delta, tv1, tv2;
static struct timeval maxtime, laststep;
struct timespec ts;
int s;
s = splclock();
microtime(&tv1);
delta = *tv;
timevalsub(&delta, &tv1);
/*
* If the system is secure, we do not allow the time to be
* set to a value earlier than 1 second less than the highest
* time we have yet seen. The worst a miscreant can do in
* this circumstance is "freeze" time. He couldn't go
* back to the past.
*
* We similarly do not allow the clock to be stepped more
* than one second, nor more than once per second. This allows
* a miscreant to make the clock march double-time, but no worse.
*/
if (securelevel_gt(td->td_ucred, 1) != 0) {
if (delta.tv_sec < 0 || delta.tv_usec < 0) {
/*
* Update maxtime to latest time we've seen.
*/
if (tv1.tv_sec > maxtime.tv_sec)
maxtime = tv1;
tv2 = *tv;
timevalsub(&tv2, &maxtime);
if (tv2.tv_sec < -1) {
tv->tv_sec = maxtime.tv_sec - 1;
printf("Time adjustment clamped to -1 second\n");
}
} else {
if (tv1.tv_sec == laststep.tv_sec) {
splx(s);
return (EPERM);
}
if (delta.tv_sec > 1) {
tv->tv_sec = tv1.tv_sec + 1;
printf("Time adjustment clamped to +1 second\n");
}
laststep = *tv;
}
}
ts.tv_sec = tv->tv_sec;
ts.tv_nsec = tv->tv_usec * 1000;
mtx_lock(&Giant);
tc_setclock(&ts);
(void) splsoftclock();
lease_updatetime(delta.tv_sec);
splx(s);
resettodr();
mtx_unlock(&Giant);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct clock_gettime_args {
clockid_t clock_id;
struct timespec *tp;
};
#endif
/* ARGSUSED */
int
clock_gettime(struct thread *td, struct clock_gettime_args *uap)
{
struct timespec ats;
int error;
error = kern_clock_gettime(td, uap->clock_id, &ats);
if (error == 0)
error = copyout(&ats, uap->tp, sizeof(ats));
return (error);
}
int
kern_clock_gettime(struct thread *td, clockid_t clock_id, struct timespec *ats)
{
struct timeval sys, user;
Rework how we store process times in the kernel such that we always store the raw values including for child process statistics and only compute the system and user timevals on demand. - Fix the various kern_wait() syscall wrappers to only pass in a rusage pointer if they are going to use the result. - Add a kern_getrusage() function for the ABI syscalls to use so that they don't have to play stackgap games to call getrusage(). - Fix the svr4_sys_times() syscall to just call calcru() to calculate the times it needs rather than calling getrusage() twice with associated stackgap, etc. - Add a new rusage_ext structure to store raw time stats such as tick counts for user, system, and interrupt time as well as a bintime of the total runtime. A new p_rux field in struct proc replaces the same inline fields from struct proc (i.e. p_[isu]ticks, p_[isu]u, and p_runtime). A new p_crux field in struct proc contains the "raw" child time usage statistics. ruadd() has been changed to handle adding the associated rusage_ext structures as well as the values in rusage. Effectively, the values in rusage_ext replace the ru_utime and ru_stime values in struct rusage. These two fields in struct rusage are no longer used in the kernel. - calcru() has been split into a static worker function calcru1() that calculates appropriate timevals for user and system time as well as updating the rux_[isu]u fields of a passed in rusage_ext structure. calcru() uses a copy of the process' p_rux structure to compute the timevals after updating the runtime appropriately if any of the threads in that process are currently executing. It also now only locks sched_lock internally while doing the rux_runtime fixup. calcru() now only requires the caller to hold the proc lock and calcru1() only requires the proc lock internally. calcru() also no longer allows callers to ask for an interrupt timeval since none of them actually did. - calcru() now correctly handles threads executing on other CPUs. - A new calccru() function computes the child system and user timevals by calling calcru1() on p_crux. Note that this means that any code that wants child times must now call this function rather than reading from p_cru directly. This function also requires the proc lock. - This finishes the locking for rusage and friends so some of the Giant locks in exit1() and kern_wait() are now gone. - The locking in ttyinfo() has been tweaked so that a shared lock of the proctree lock is used to protect the process group rather than the process group lock. By holding this lock until the end of the function we now ensure that the process/thread that we pick to dump info about will no longer vanish while we are trying to output its info to the console. Submitted by: bde (mostly) MFC after: 1 month
2004-10-05 18:51:11 +00:00
struct proc *p;
Rework how we store process times in the kernel such that we always store the raw values including for child process statistics and only compute the system and user timevals on demand. - Fix the various kern_wait() syscall wrappers to only pass in a rusage pointer if they are going to use the result. - Add a kern_getrusage() function for the ABI syscalls to use so that they don't have to play stackgap games to call getrusage(). - Fix the svr4_sys_times() syscall to just call calcru() to calculate the times it needs rather than calling getrusage() twice with associated stackgap, etc. - Add a new rusage_ext structure to store raw time stats such as tick counts for user, system, and interrupt time as well as a bintime of the total runtime. A new p_rux field in struct proc replaces the same inline fields from struct proc (i.e. p_[isu]ticks, p_[isu]u, and p_runtime). A new p_crux field in struct proc contains the "raw" child time usage statistics. ruadd() has been changed to handle adding the associated rusage_ext structures as well as the values in rusage. Effectively, the values in rusage_ext replace the ru_utime and ru_stime values in struct rusage. These two fields in struct rusage are no longer used in the kernel. - calcru() has been split into a static worker function calcru1() that calculates appropriate timevals for user and system time as well as updating the rux_[isu]u fields of a passed in rusage_ext structure. calcru() uses a copy of the process' p_rux structure to compute the timevals after updating the runtime appropriately if any of the threads in that process are currently executing. It also now only locks sched_lock internally while doing the rux_runtime fixup. calcru() now only requires the caller to hold the proc lock and calcru1() only requires the proc lock internally. calcru() also no longer allows callers to ask for an interrupt timeval since none of them actually did. - calcru() now correctly handles threads executing on other CPUs. - A new calccru() function computes the child system and user timevals by calling calcru1() on p_crux. Note that this means that any code that wants child times must now call this function rather than reading from p_cru directly. This function also requires the proc lock. - This finishes the locking for rusage and friends so some of the Giant locks in exit1() and kern_wait() are now gone. - The locking in ttyinfo() has been tweaked so that a shared lock of the proctree lock is used to protect the process group rather than the process group lock. By holding this lock until the end of the function we now ensure that the process/thread that we pick to dump info about will no longer vanish while we are trying to output its info to the console. Submitted by: bde (mostly) MFC after: 1 month
2004-10-05 18:51:11 +00:00
p = td->td_proc;
switch (clock_id) {
Add several aliases for existing clockid_t names to indicate that the application wishes to request high precision time stamps be returned: Alias Existing CLOCK_REALTIME_PRECISE CLOCK_REALTIME CLOCK_MONOTONIC_PRECISE CLOCK_MONOTONIC CLOCK_UPTIME_PRECISE CLOCK_UPTIME Add experimental low-precision clockid_t names corresponding to these clocks, but implemented using cached timestamps in kernel rather than a full time counter query. This offers a minimum update rate of 1/HZ, but in practice will often be more frequent due to the frequency of time stamping in the kernel: New clockid_t name Approximates existing clockid_t CLOCK_REALTIME_FAST CLOCK_REALTIME CLOCK_MONOTONIC_FAST CLOCK_MONOTONIC CLOCK_UPTIME_FAST CLOCK_UPTIME Add one additional new clockid_t, CLOCK_SECOND, which returns the current second without performing a full time counter query or cache lookup overhead to make sure the cached timestamp is stable. This is intended to support very low granularity consumers, such as time(3). The names, visibility, and implementation of the above are subject to change, and will not be MFC'd any time soon. The goal is to expose lower quality time measurement to applications willing to sacrifice accuracy in performance critical paths, such as when taking time stamps for the purpose of rescheduling select() and poll() timeouts. Future changes might include retrofitting the time counter infrastructure to allow the "fast" time query mechanisms to use a different time counter, rather than a cached time counter (i.e., TSC). NOTE: With different underlying time mechanisms exposed, using different time query mechanisms in the same application may result in relative non-monoticity or the appearance of clock stalling for a single clockid_t, as a cached time stamp queried after a precision time stamp lookup may be "before" the time returned by the earlier live time counter query.
2005-11-27 00:55:18 +00:00
case CLOCK_REALTIME: /* Default to precise. */
case CLOCK_REALTIME_PRECISE:
nanotime(ats);
break;
Add several aliases for existing clockid_t names to indicate that the application wishes to request high precision time stamps be returned: Alias Existing CLOCK_REALTIME_PRECISE CLOCK_REALTIME CLOCK_MONOTONIC_PRECISE CLOCK_MONOTONIC CLOCK_UPTIME_PRECISE CLOCK_UPTIME Add experimental low-precision clockid_t names corresponding to these clocks, but implemented using cached timestamps in kernel rather than a full time counter query. This offers a minimum update rate of 1/HZ, but in practice will often be more frequent due to the frequency of time stamping in the kernel: New clockid_t name Approximates existing clockid_t CLOCK_REALTIME_FAST CLOCK_REALTIME CLOCK_MONOTONIC_FAST CLOCK_MONOTONIC CLOCK_UPTIME_FAST CLOCK_UPTIME Add one additional new clockid_t, CLOCK_SECOND, which returns the current second without performing a full time counter query or cache lookup overhead to make sure the cached timestamp is stable. This is intended to support very low granularity consumers, such as time(3). The names, visibility, and implementation of the above are subject to change, and will not be MFC'd any time soon. The goal is to expose lower quality time measurement to applications willing to sacrifice accuracy in performance critical paths, such as when taking time stamps for the purpose of rescheduling select() and poll() timeouts. Future changes might include retrofitting the time counter infrastructure to allow the "fast" time query mechanisms to use a different time counter, rather than a cached time counter (i.e., TSC). NOTE: With different underlying time mechanisms exposed, using different time query mechanisms in the same application may result in relative non-monoticity or the appearance of clock stalling for a single clockid_t, as a cached time stamp queried after a precision time stamp lookup may be "before" the time returned by the earlier live time counter query.
2005-11-27 00:55:18 +00:00
case CLOCK_REALTIME_FAST:
getnanotime(ats);
break;
case CLOCK_VIRTUAL:
Rework how we store process times in the kernel such that we always store the raw values including for child process statistics and only compute the system and user timevals on demand. - Fix the various kern_wait() syscall wrappers to only pass in a rusage pointer if they are going to use the result. - Add a kern_getrusage() function for the ABI syscalls to use so that they don't have to play stackgap games to call getrusage(). - Fix the svr4_sys_times() syscall to just call calcru() to calculate the times it needs rather than calling getrusage() twice with associated stackgap, etc. - Add a new rusage_ext structure to store raw time stats such as tick counts for user, system, and interrupt time as well as a bintime of the total runtime. A new p_rux field in struct proc replaces the same inline fields from struct proc (i.e. p_[isu]ticks, p_[isu]u, and p_runtime). A new p_crux field in struct proc contains the "raw" child time usage statistics. ruadd() has been changed to handle adding the associated rusage_ext structures as well as the values in rusage. Effectively, the values in rusage_ext replace the ru_utime and ru_stime values in struct rusage. These two fields in struct rusage are no longer used in the kernel. - calcru() has been split into a static worker function calcru1() that calculates appropriate timevals for user and system time as well as updating the rux_[isu]u fields of a passed in rusage_ext structure. calcru() uses a copy of the process' p_rux structure to compute the timevals after updating the runtime appropriately if any of the threads in that process are currently executing. It also now only locks sched_lock internally while doing the rux_runtime fixup. calcru() now only requires the caller to hold the proc lock and calcru1() only requires the proc lock internally. calcru() also no longer allows callers to ask for an interrupt timeval since none of them actually did. - calcru() now correctly handles threads executing on other CPUs. - A new calccru() function computes the child system and user timevals by calling calcru1() on p_crux. Note that this means that any code that wants child times must now call this function rather than reading from p_cru directly. This function also requires the proc lock. - This finishes the locking for rusage and friends so some of the Giant locks in exit1() and kern_wait() are now gone. - The locking in ttyinfo() has been tweaked so that a shared lock of the proctree lock is used to protect the process group rather than the process group lock. By holding this lock until the end of the function we now ensure that the process/thread that we pick to dump info about will no longer vanish while we are trying to output its info to the console. Submitted by: bde (mostly) MFC after: 1 month
2004-10-05 18:51:11 +00:00
PROC_LOCK(p);
calcru(p, &user, &sys);
PROC_UNLOCK(p);
TIMEVAL_TO_TIMESPEC(&user, ats);
break;
case CLOCK_PROF:
Rework how we store process times in the kernel such that we always store the raw values including for child process statistics and only compute the system and user timevals on demand. - Fix the various kern_wait() syscall wrappers to only pass in a rusage pointer if they are going to use the result. - Add a kern_getrusage() function for the ABI syscalls to use so that they don't have to play stackgap games to call getrusage(). - Fix the svr4_sys_times() syscall to just call calcru() to calculate the times it needs rather than calling getrusage() twice with associated stackgap, etc. - Add a new rusage_ext structure to store raw time stats such as tick counts for user, system, and interrupt time as well as a bintime of the total runtime. A new p_rux field in struct proc replaces the same inline fields from struct proc (i.e. p_[isu]ticks, p_[isu]u, and p_runtime). A new p_crux field in struct proc contains the "raw" child time usage statistics. ruadd() has been changed to handle adding the associated rusage_ext structures as well as the values in rusage. Effectively, the values in rusage_ext replace the ru_utime and ru_stime values in struct rusage. These two fields in struct rusage are no longer used in the kernel. - calcru() has been split into a static worker function calcru1() that calculates appropriate timevals for user and system time as well as updating the rux_[isu]u fields of a passed in rusage_ext structure. calcru() uses a copy of the process' p_rux structure to compute the timevals after updating the runtime appropriately if any of the threads in that process are currently executing. It also now only locks sched_lock internally while doing the rux_runtime fixup. calcru() now only requires the caller to hold the proc lock and calcru1() only requires the proc lock internally. calcru() also no longer allows callers to ask for an interrupt timeval since none of them actually did. - calcru() now correctly handles threads executing on other CPUs. - A new calccru() function computes the child system and user timevals by calling calcru1() on p_crux. Note that this means that any code that wants child times must now call this function rather than reading from p_cru directly. This function also requires the proc lock. - This finishes the locking for rusage and friends so some of the Giant locks in exit1() and kern_wait() are now gone. - The locking in ttyinfo() has been tweaked so that a shared lock of the proctree lock is used to protect the process group rather than the process group lock. By holding this lock until the end of the function we now ensure that the process/thread that we pick to dump info about will no longer vanish while we are trying to output its info to the console. Submitted by: bde (mostly) MFC after: 1 month
2004-10-05 18:51:11 +00:00
PROC_LOCK(p);
calcru(p, &user, &sys);
PROC_UNLOCK(p);
timevaladd(&user, &sys);
TIMEVAL_TO_TIMESPEC(&user, ats);
break;
Add several aliases for existing clockid_t names to indicate that the application wishes to request high precision time stamps be returned: Alias Existing CLOCK_REALTIME_PRECISE CLOCK_REALTIME CLOCK_MONOTONIC_PRECISE CLOCK_MONOTONIC CLOCK_UPTIME_PRECISE CLOCK_UPTIME Add experimental low-precision clockid_t names corresponding to these clocks, but implemented using cached timestamps in kernel rather than a full time counter query. This offers a minimum update rate of 1/HZ, but in practice will often be more frequent due to the frequency of time stamping in the kernel: New clockid_t name Approximates existing clockid_t CLOCK_REALTIME_FAST CLOCK_REALTIME CLOCK_MONOTONIC_FAST CLOCK_MONOTONIC CLOCK_UPTIME_FAST CLOCK_UPTIME Add one additional new clockid_t, CLOCK_SECOND, which returns the current second without performing a full time counter query or cache lookup overhead to make sure the cached timestamp is stable. This is intended to support very low granularity consumers, such as time(3). The names, visibility, and implementation of the above are subject to change, and will not be MFC'd any time soon. The goal is to expose lower quality time measurement to applications willing to sacrifice accuracy in performance critical paths, such as when taking time stamps for the purpose of rescheduling select() and poll() timeouts. Future changes might include retrofitting the time counter infrastructure to allow the "fast" time query mechanisms to use a different time counter, rather than a cached time counter (i.e., TSC). NOTE: With different underlying time mechanisms exposed, using different time query mechanisms in the same application may result in relative non-monoticity or the appearance of clock stalling for a single clockid_t, as a cached time stamp queried after a precision time stamp lookup may be "before" the time returned by the earlier live time counter query.
2005-11-27 00:55:18 +00:00
case CLOCK_MONOTONIC: /* Default to precise. */
case CLOCK_MONOTONIC_PRECISE:
case CLOCK_UPTIME:
Add several aliases for existing clockid_t names to indicate that the application wishes to request high precision time stamps be returned: Alias Existing CLOCK_REALTIME_PRECISE CLOCK_REALTIME CLOCK_MONOTONIC_PRECISE CLOCK_MONOTONIC CLOCK_UPTIME_PRECISE CLOCK_UPTIME Add experimental low-precision clockid_t names corresponding to these clocks, but implemented using cached timestamps in kernel rather than a full time counter query. This offers a minimum update rate of 1/HZ, but in practice will often be more frequent due to the frequency of time stamping in the kernel: New clockid_t name Approximates existing clockid_t CLOCK_REALTIME_FAST CLOCK_REALTIME CLOCK_MONOTONIC_FAST CLOCK_MONOTONIC CLOCK_UPTIME_FAST CLOCK_UPTIME Add one additional new clockid_t, CLOCK_SECOND, which returns the current second without performing a full time counter query or cache lookup overhead to make sure the cached timestamp is stable. This is intended to support very low granularity consumers, such as time(3). The names, visibility, and implementation of the above are subject to change, and will not be MFC'd any time soon. The goal is to expose lower quality time measurement to applications willing to sacrifice accuracy in performance critical paths, such as when taking time stamps for the purpose of rescheduling select() and poll() timeouts. Future changes might include retrofitting the time counter infrastructure to allow the "fast" time query mechanisms to use a different time counter, rather than a cached time counter (i.e., TSC). NOTE: With different underlying time mechanisms exposed, using different time query mechanisms in the same application may result in relative non-monoticity or the appearance of clock stalling for a single clockid_t, as a cached time stamp queried after a precision time stamp lookup may be "before" the time returned by the earlier live time counter query.
2005-11-27 00:55:18 +00:00
case CLOCK_UPTIME_PRECISE:
nanouptime(ats);
break;
Add several aliases for existing clockid_t names to indicate that the application wishes to request high precision time stamps be returned: Alias Existing CLOCK_REALTIME_PRECISE CLOCK_REALTIME CLOCK_MONOTONIC_PRECISE CLOCK_MONOTONIC CLOCK_UPTIME_PRECISE CLOCK_UPTIME Add experimental low-precision clockid_t names corresponding to these clocks, but implemented using cached timestamps in kernel rather than a full time counter query. This offers a minimum update rate of 1/HZ, but in practice will often be more frequent due to the frequency of time stamping in the kernel: New clockid_t name Approximates existing clockid_t CLOCK_REALTIME_FAST CLOCK_REALTIME CLOCK_MONOTONIC_FAST CLOCK_MONOTONIC CLOCK_UPTIME_FAST CLOCK_UPTIME Add one additional new clockid_t, CLOCK_SECOND, which returns the current second without performing a full time counter query or cache lookup overhead to make sure the cached timestamp is stable. This is intended to support very low granularity consumers, such as time(3). The names, visibility, and implementation of the above are subject to change, and will not be MFC'd any time soon. The goal is to expose lower quality time measurement to applications willing to sacrifice accuracy in performance critical paths, such as when taking time stamps for the purpose of rescheduling select() and poll() timeouts. Future changes might include retrofitting the time counter infrastructure to allow the "fast" time query mechanisms to use a different time counter, rather than a cached time counter (i.e., TSC). NOTE: With different underlying time mechanisms exposed, using different time query mechanisms in the same application may result in relative non-monoticity or the appearance of clock stalling for a single clockid_t, as a cached time stamp queried after a precision time stamp lookup may be "before" the time returned by the earlier live time counter query.
2005-11-27 00:55:18 +00:00
case CLOCK_UPTIME_FAST:
case CLOCK_MONOTONIC_FAST:
getnanouptime(ats);
break;
case CLOCK_SECOND:
ats->tv_sec = time_second;
ats->tv_nsec = 0;
break;
default:
return (EINVAL);
}
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct clock_settime_args {
clockid_t clock_id;
const struct timespec *tp;
};
#endif
/* ARGSUSED */
int
clock_settime(struct thread *td, struct clock_settime_args *uap)
{
struct timespec ats;
int error;
if ((error = copyin(uap->tp, &ats, sizeof(ats))) != 0)
return (error);
return (kern_clock_settime(td, uap->clock_id, &ats));
}
int
kern_clock_settime(struct thread *td, clockid_t clock_id, struct timespec *ats)
{
struct timeval atv;
int error;
if ((error = priv_check(td, PRIV_CLOCK_SETTIME)) != 0)
return (error);
if (clock_id != CLOCK_REALTIME)
return (EINVAL);
if (ats->tv_nsec < 0 || ats->tv_nsec >= 1000000000)
return (EINVAL);
/* XXX Don't convert nsec->usec and back */
TIMESPEC_TO_TIMEVAL(&atv, ats);
error = settime(td, &atv);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct clock_getres_args {
clockid_t clock_id;
struct timespec *tp;
};
#endif
int
clock_getres(struct thread *td, struct clock_getres_args *uap)
{
struct timespec ts;
int error;
if (uap->tp == NULL)
return (0);
error = kern_clock_getres(td, uap->clock_id, &ts);
if (error == 0)
error = copyout(&ts, uap->tp, sizeof(ts));
return (error);
}
int
kern_clock_getres(struct thread *td, clockid_t clock_id, struct timespec *ts)
{
ts->tv_sec = 0;
switch (clock_id) {
case CLOCK_REALTIME:
Add several aliases for existing clockid_t names to indicate that the application wishes to request high precision time stamps be returned: Alias Existing CLOCK_REALTIME_PRECISE CLOCK_REALTIME CLOCK_MONOTONIC_PRECISE CLOCK_MONOTONIC CLOCK_UPTIME_PRECISE CLOCK_UPTIME Add experimental low-precision clockid_t names corresponding to these clocks, but implemented using cached timestamps in kernel rather than a full time counter query. This offers a minimum update rate of 1/HZ, but in practice will often be more frequent due to the frequency of time stamping in the kernel: New clockid_t name Approximates existing clockid_t CLOCK_REALTIME_FAST CLOCK_REALTIME CLOCK_MONOTONIC_FAST CLOCK_MONOTONIC CLOCK_UPTIME_FAST CLOCK_UPTIME Add one additional new clockid_t, CLOCK_SECOND, which returns the current second without performing a full time counter query or cache lookup overhead to make sure the cached timestamp is stable. This is intended to support very low granularity consumers, such as time(3). The names, visibility, and implementation of the above are subject to change, and will not be MFC'd any time soon. The goal is to expose lower quality time measurement to applications willing to sacrifice accuracy in performance critical paths, such as when taking time stamps for the purpose of rescheduling select() and poll() timeouts. Future changes might include retrofitting the time counter infrastructure to allow the "fast" time query mechanisms to use a different time counter, rather than a cached time counter (i.e., TSC). NOTE: With different underlying time mechanisms exposed, using different time query mechanisms in the same application may result in relative non-monoticity or the appearance of clock stalling for a single clockid_t, as a cached time stamp queried after a precision time stamp lookup may be "before" the time returned by the earlier live time counter query.
2005-11-27 00:55:18 +00:00
case CLOCK_REALTIME_FAST:
case CLOCK_REALTIME_PRECISE:
case CLOCK_MONOTONIC:
Add several aliases for existing clockid_t names to indicate that the application wishes to request high precision time stamps be returned: Alias Existing CLOCK_REALTIME_PRECISE CLOCK_REALTIME CLOCK_MONOTONIC_PRECISE CLOCK_MONOTONIC CLOCK_UPTIME_PRECISE CLOCK_UPTIME Add experimental low-precision clockid_t names corresponding to these clocks, but implemented using cached timestamps in kernel rather than a full time counter query. This offers a minimum update rate of 1/HZ, but in practice will often be more frequent due to the frequency of time stamping in the kernel: New clockid_t name Approximates existing clockid_t CLOCK_REALTIME_FAST CLOCK_REALTIME CLOCK_MONOTONIC_FAST CLOCK_MONOTONIC CLOCK_UPTIME_FAST CLOCK_UPTIME Add one additional new clockid_t, CLOCK_SECOND, which returns the current second without performing a full time counter query or cache lookup overhead to make sure the cached timestamp is stable. This is intended to support very low granularity consumers, such as time(3). The names, visibility, and implementation of the above are subject to change, and will not be MFC'd any time soon. The goal is to expose lower quality time measurement to applications willing to sacrifice accuracy in performance critical paths, such as when taking time stamps for the purpose of rescheduling select() and poll() timeouts. Future changes might include retrofitting the time counter infrastructure to allow the "fast" time query mechanisms to use a different time counter, rather than a cached time counter (i.e., TSC). NOTE: With different underlying time mechanisms exposed, using different time query mechanisms in the same application may result in relative non-monoticity or the appearance of clock stalling for a single clockid_t, as a cached time stamp queried after a precision time stamp lookup may be "before" the time returned by the earlier live time counter query.
2005-11-27 00:55:18 +00:00
case CLOCK_MONOTONIC_FAST:
case CLOCK_MONOTONIC_PRECISE:
case CLOCK_UPTIME:
Add several aliases for existing clockid_t names to indicate that the application wishes to request high precision time stamps be returned: Alias Existing CLOCK_REALTIME_PRECISE CLOCK_REALTIME CLOCK_MONOTONIC_PRECISE CLOCK_MONOTONIC CLOCK_UPTIME_PRECISE CLOCK_UPTIME Add experimental low-precision clockid_t names corresponding to these clocks, but implemented using cached timestamps in kernel rather than a full time counter query. This offers a minimum update rate of 1/HZ, but in practice will often be more frequent due to the frequency of time stamping in the kernel: New clockid_t name Approximates existing clockid_t CLOCK_REALTIME_FAST CLOCK_REALTIME CLOCK_MONOTONIC_FAST CLOCK_MONOTONIC CLOCK_UPTIME_FAST CLOCK_UPTIME Add one additional new clockid_t, CLOCK_SECOND, which returns the current second without performing a full time counter query or cache lookup overhead to make sure the cached timestamp is stable. This is intended to support very low granularity consumers, such as time(3). The names, visibility, and implementation of the above are subject to change, and will not be MFC'd any time soon. The goal is to expose lower quality time measurement to applications willing to sacrifice accuracy in performance critical paths, such as when taking time stamps for the purpose of rescheduling select() and poll() timeouts. Future changes might include retrofitting the time counter infrastructure to allow the "fast" time query mechanisms to use a different time counter, rather than a cached time counter (i.e., TSC). NOTE: With different underlying time mechanisms exposed, using different time query mechanisms in the same application may result in relative non-monoticity or the appearance of clock stalling for a single clockid_t, as a cached time stamp queried after a precision time stamp lookup may be "before" the time returned by the earlier live time counter query.
2005-11-27 00:55:18 +00:00
case CLOCK_UPTIME_FAST:
case CLOCK_UPTIME_PRECISE:
/*
* Round up the result of the division cheaply by adding 1.
* Rounding up is especially important if rounding down
* would give 0. Perfect rounding is unimportant.
*/
ts->tv_nsec = 1000000000 / tc_getfrequency() + 1;
break;
case CLOCK_VIRTUAL:
case CLOCK_PROF:
/* Accurately round up here because we can do so cheaply. */
ts->tv_nsec = (1000000000 + hz - 1) / hz;
break;
Add several aliases for existing clockid_t names to indicate that the application wishes to request high precision time stamps be returned: Alias Existing CLOCK_REALTIME_PRECISE CLOCK_REALTIME CLOCK_MONOTONIC_PRECISE CLOCK_MONOTONIC CLOCK_UPTIME_PRECISE CLOCK_UPTIME Add experimental low-precision clockid_t names corresponding to these clocks, but implemented using cached timestamps in kernel rather than a full time counter query. This offers a minimum update rate of 1/HZ, but in practice will often be more frequent due to the frequency of time stamping in the kernel: New clockid_t name Approximates existing clockid_t CLOCK_REALTIME_FAST CLOCK_REALTIME CLOCK_MONOTONIC_FAST CLOCK_MONOTONIC CLOCK_UPTIME_FAST CLOCK_UPTIME Add one additional new clockid_t, CLOCK_SECOND, which returns the current second without performing a full time counter query or cache lookup overhead to make sure the cached timestamp is stable. This is intended to support very low granularity consumers, such as time(3). The names, visibility, and implementation of the above are subject to change, and will not be MFC'd any time soon. The goal is to expose lower quality time measurement to applications willing to sacrifice accuracy in performance critical paths, such as when taking time stamps for the purpose of rescheduling select() and poll() timeouts. Future changes might include retrofitting the time counter infrastructure to allow the "fast" time query mechanisms to use a different time counter, rather than a cached time counter (i.e., TSC). NOTE: With different underlying time mechanisms exposed, using different time query mechanisms in the same application may result in relative non-monoticity or the appearance of clock stalling for a single clockid_t, as a cached time stamp queried after a precision time stamp lookup may be "before" the time returned by the earlier live time counter query.
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case CLOCK_SECOND:
ts->tv_sec = 1;
ts->tv_nsec = 0;
break;
default:
return (EINVAL);
}
return (0);
}
static int nanowait;
int
kern_nanosleep(struct thread *td, struct timespec *rqt, struct timespec *rmt)
{
struct timespec ts, ts2, ts3;
struct timeval tv;
int error;
if (rqt->tv_nsec < 0 || rqt->tv_nsec >= 1000000000)
return (EINVAL);
if (rqt->tv_sec < 0 || (rqt->tv_sec == 0 && rqt->tv_nsec == 0))
return (0);
getnanouptime(&ts);
timespecadd(&ts, rqt);
TIMESPEC_TO_TIMEVAL(&tv, rqt);
for (;;) {
error = tsleep(&nanowait, PWAIT | PCATCH, "nanslp",
tvtohz(&tv));
getnanouptime(&ts2);
if (error != EWOULDBLOCK) {
if (error == ERESTART)
error = EINTR;
if (rmt != NULL) {
timespecsub(&ts, &ts2);
if (ts.tv_sec < 0)
timespecclear(&ts);
*rmt = ts;
}
return (error);
}
if (timespeccmp(&ts2, &ts, >=))
return (0);
ts3 = ts;
timespecsub(&ts3, &ts2);
TIMESPEC_TO_TIMEVAL(&tv, &ts3);
}
}
#ifndef _SYS_SYSPROTO_H_
struct nanosleep_args {
struct timespec *rqtp;
struct timespec *rmtp;
};
#endif
/* ARGSUSED */
int
nanosleep(struct thread *td, struct nanosleep_args *uap)
{
struct timespec rmt, rqt;
int error;
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error = copyin(uap->rqtp, &rqt, sizeof(rqt));
if (error)
return (error);
if (uap->rmtp &&
!useracc((caddr_t)uap->rmtp, sizeof(rmt), VM_PROT_WRITE))
return (EFAULT);
error = kern_nanosleep(td, &rqt, &rmt);
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if (error && uap->rmtp) {
int error2;
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error2 = copyout(&rmt, uap->rmtp, sizeof(rmt));
if (error2)
error = error2;
}
return (error);
}
#ifndef _SYS_SYSPROTO_H_
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struct gettimeofday_args {
struct timeval *tp;
struct timezone *tzp;
};
#endif
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/* ARGSUSED */
int
gettimeofday(struct thread *td, struct gettimeofday_args *uap)
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{
struct timeval atv;
struct timezone rtz;
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int error = 0;
if (uap->tp) {
microtime(&atv);
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error = copyout(&atv, uap->tp, sizeof (atv));
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}
if (error == 0 && uap->tzp != NULL) {
rtz.tz_minuteswest = tz_minuteswest;
rtz.tz_dsttime = tz_dsttime;
error = copyout(&rtz, uap->tzp, sizeof (rtz));
}
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return (error);
}
#ifndef _SYS_SYSPROTO_H_
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struct settimeofday_args {
struct timeval *tv;
struct timezone *tzp;
};
#endif
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/* ARGSUSED */
int
settimeofday(struct thread *td, struct settimeofday_args *uap)
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{
struct timeval atv, *tvp;
struct timezone atz, *tzp;
int error;
if (uap->tv) {
error = copyin(uap->tv, &atv, sizeof(atv));
if (error)
return (error);
tvp = &atv;
} else
tvp = NULL;
if (uap->tzp) {
error = copyin(uap->tzp, &atz, sizeof(atz));
if (error)
return (error);
tzp = &atz;
} else
tzp = NULL;
return (kern_settimeofday(td, tvp, tzp));
}
int
kern_settimeofday(struct thread *td, struct timeval *tv, struct timezone *tzp)
{
int error;
error = priv_check(td, PRIV_SETTIMEOFDAY);
if (error)
return (error);
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/* Verify all parameters before changing time. */
if (tv) {
if (tv->tv_usec < 0 || tv->tv_usec >= 1000000)
return (EINVAL);
error = settime(td, tv);
}
if (tzp && error == 0) {
tz_minuteswest = tzp->tz_minuteswest;
tz_dsttime = tzp->tz_dsttime;
}
return (error);
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}
1994-05-24 10:09:53 +00:00
/*
* Get value of an interval timer. The process virtual and profiling virtual
* time timers are kept in the p_stats area, since they can be swapped out.
* These are kept internally in the way they are specified externally: in
* time until they expire.
1994-05-24 10:09:53 +00:00
*
* The real time interval timer is kept in the process table slot for the
* process, and its value (it_value) is kept as an absolute time rather than
* as a delta, so that it is easy to keep periodic real-time signals from
* drifting.
1994-05-24 10:09:53 +00:00
*
* Virtual time timers are processed in the hardclock() routine of
* kern_clock.c. The real time timer is processed by a timeout 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 (realitexpire, 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.
1994-05-24 10:09:53 +00:00
*/
#ifndef _SYS_SYSPROTO_H_
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struct getitimer_args {
u_int which;
struct itimerval *itv;
};
#endif
int
getitimer(struct thread *td, struct getitimer_args *uap)
{
struct itimerval aitv;
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int error;
error = kern_getitimer(td, uap->which, &aitv);
if (error != 0)
return (error);
return (copyout(&aitv, uap->itv, sizeof (struct itimerval)));
}
int
kern_getitimer(struct thread *td, u_int which, struct itimerval *aitv)
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{
struct proc *p = td->td_proc;
struct timeval ctv;
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if (which > ITIMER_PROF)
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return (EINVAL);
if (which == ITIMER_REAL) {
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/*
* Convert from absolute to relative time in .it_value
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* 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.
*/
PROC_LOCK(p);
*aitv = p->p_realtimer;
PROC_UNLOCK(p);
if (timevalisset(&aitv->it_value)) {
getmicrouptime(&ctv);
if (timevalcmp(&aitv->it_value, &ctv, <))
timevalclear(&aitv->it_value);
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else
timevalsub(&aitv->it_value, &ctv);
}
} else {
mtx_lock_spin(&sched_lock);
*aitv = p->p_stats->p_timer[which];
mtx_unlock_spin(&sched_lock);
}
return (0);
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}
#ifndef _SYS_SYSPROTO_H_
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struct setitimer_args {
u_int which;
struct itimerval *itv, *oitv;
};
#endif
int
setitimer(struct thread *td, struct setitimer_args *uap)
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{
struct itimerval aitv, oitv;
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int error;
if (uap->itv == NULL) {
uap->itv = uap->oitv;
return (getitimer(td, (struct getitimer_args *)uap));
}
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if ((error = copyin(uap->itv, &aitv, sizeof(struct itimerval))))
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return (error);
error = kern_setitimer(td, uap->which, &aitv, &oitv);
if (error != 0 || uap->oitv == NULL)
return (error);
return (copyout(&oitv, uap->oitv, sizeof(struct itimerval)));
}
int
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kern_setitimer(struct thread *td, u_int which, struct itimerval *aitv,
struct itimerval *oitv)
{
struct proc *p = td->td_proc;
struct timeval ctv;
if (aitv == NULL)
return (kern_getitimer(td, which, oitv));
if (which > ITIMER_PROF)
return (EINVAL);
if (itimerfix(&aitv->it_value))
return (EINVAL);
if (!timevalisset(&aitv->it_value))
timevalclear(&aitv->it_interval);
else if (itimerfix(&aitv->it_interval))
return (EINVAL);
if (which == ITIMER_REAL) {
PROC_LOCK(p);
if (timevalisset(&p->p_realtimer.it_value))
callout_stop(&p->p_itcallout);
getmicrouptime(&ctv);
if (timevalisset(&aitv->it_value)) {
callout_reset(&p->p_itcallout, tvtohz(&aitv->it_value),
realitexpire, p);
timevaladd(&aitv->it_value, &ctv);
}
*oitv = p->p_realtimer;
p->p_realtimer = *aitv;
PROC_UNLOCK(p);
if (timevalisset(&oitv->it_value)) {
if (timevalcmp(&oitv->it_value, &ctv, <))
timevalclear(&oitv->it_value);
else
timevalsub(&oitv->it_value, &ctv);
}
} else {
mtx_lock_spin(&sched_lock);
*oitv = p->p_stats->p_timer[which];
p->p_stats->p_timer[which] = *aitv;
mtx_unlock_spin(&sched_lock);
}
return (0);
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}
/*
* 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.
* tvtohz() always adds 1 to allow for the time until the next clock
* interrupt being strictly less than 1 clock tick, but we don't want
* that here since we want to appear to be in sync with the clock
* interrupt even when we're delayed.
1994-05-24 10:09:53 +00:00
*/
void
realitexpire(void *arg)
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{
struct proc *p;
struct timeval ctv, ntv;
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p = (struct proc *)arg;
PROC_LOCK(p);
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psignal(p, SIGALRM);
if (!timevalisset(&p->p_realtimer.it_interval)) {
timevalclear(&p->p_realtimer.it_value);
if (p->p_flag & P_WEXIT)
wakeup(&p->p_itcallout);
PROC_UNLOCK(p);
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return;
}
for (;;) {
timevaladd(&p->p_realtimer.it_value,
&p->p_realtimer.it_interval);
getmicrouptime(&ctv);
if (timevalcmp(&p->p_realtimer.it_value, &ctv, >)) {
ntv = p->p_realtimer.it_value;
timevalsub(&ntv, &ctv);
callout_reset(&p->p_itcallout, tvtohz(&ntv) - 1,
realitexpire, p);
PROC_UNLOCK(p);
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return;
}
}
/*NOTREACHED*/
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}
/*
* Check that a proposed value to load into the .it_value or
* .it_interval part of an interval timer is acceptable, and
* fix it to have at least minimal value (i.e. if it is less
* than the resolution of the clock, round it up.)
*/
int
itimerfix(struct timeval *tv)
1994-05-24 10:09:53 +00:00
{
if (tv->tv_sec < 0 || tv->tv_usec < 0 || tv->tv_usec >= 1000000)
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return (EINVAL);
if (tv->tv_sec == 0 && tv->tv_usec != 0 && tv->tv_usec < tick)
tv->tv_usec = tick;
return (0);
}
/*
* Decrement an interval timer by a specified number
* of microseconds, which must be less than a second,
* i.e. < 1000000. If the timer expires, then reload
* it. In this case, carry over (usec - 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.
*/
int
itimerdecr(struct itimerval *itp, int usec)
1994-05-24 10:09:53 +00:00
{
if (itp->it_value.tv_usec < usec) {
if (itp->it_value.tv_sec == 0) {
/* expired, and already in next interval */
usec -= itp->it_value.tv_usec;
goto expire;
}
itp->it_value.tv_usec += 1000000;
itp->it_value.tv_sec--;
}
itp->it_value.tv_usec -= usec;
usec = 0;
if (timevalisset(&itp->it_value))
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return (1);
/* expired, exactly at end of interval */
expire:
if (timevalisset(&itp->it_interval)) {
1994-05-24 10:09:53 +00:00
itp->it_value = itp->it_interval;
itp->it_value.tv_usec -= usec;
if (itp->it_value.tv_usec < 0) {
itp->it_value.tv_usec += 1000000;
itp->it_value.tv_sec--;
}
} else
itp->it_value.tv_usec = 0; /* sec is already 0 */
return (0);
}
/*
* Add and subtract routines for timevals.
* N.B.: subtract routine doesn't deal with
* results which are before the beginning,
* it just gets very confused in this case.
* Caveat emptor.
*/
void
timevaladd(struct timeval *t1, const struct timeval *t2)
1994-05-24 10:09:53 +00:00
{
t1->tv_sec += t2->tv_sec;
t1->tv_usec += t2->tv_usec;
timevalfix(t1);
}
void
timevalsub(struct timeval *t1, const struct timeval *t2)
1994-05-24 10:09:53 +00:00
{
t1->tv_sec -= t2->tv_sec;
t1->tv_usec -= t2->tv_usec;
timevalfix(t1);
}
static void
timevalfix(struct timeval *t1)
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{
if (t1->tv_usec < 0) {
t1->tv_sec--;
t1->tv_usec += 1000000;
}
if (t1->tv_usec >= 1000000) {
t1->tv_sec++;
t1->tv_usec -= 1000000;
}
}
/*
* ratecheck(): simple time-based rate-limit checking.
*/
int
ratecheck(struct timeval *lasttime, const struct timeval *mininterval)
{
struct timeval tv, delta;
int rv = 0;
getmicrouptime(&tv); /* NB: 10ms precision */
delta = tv;
timevalsub(&delta, lasttime);
/*
* check for 0,0 is so that the message will be seen at least once,
* even if interval is huge.
*/
if (timevalcmp(&delta, mininterval, >=) ||
(lasttime->tv_sec == 0 && lasttime->tv_usec == 0)) {
*lasttime = tv;
rv = 1;
}
return (rv);
}
/*
* ppsratecheck(): packets (or events) per second limitation.
*
* Return 0 if the limit is to be enforced (e.g. the caller
* should drop a packet because of the rate limitation).
*
* maxpps of 0 always causes zero to be returned. maxpps of -1
* always causes 1 to be returned; this effectively defeats rate
* limiting.
*
* Note that we maintain the struct timeval for compatibility
* with other bsd systems. We reuse the storage and just monitor
* clock ticks for minimal overhead.
*/
int
ppsratecheck(struct timeval *lasttime, int *curpps, int maxpps)
{
int now;
/*
* Reset the last time and counter if this is the first call
* or more than a second has passed since the last update of
* lasttime.
*/
now = ticks;
if (lasttime->tv_sec == 0 || (u_int)(now - lasttime->tv_sec) >= hz) {
lasttime->tv_sec = now;
*curpps = 1;
return (maxpps != 0);
} else {
(*curpps)++; /* NB: ignore potential overflow */
return (maxpps < 0 || *curpps < maxpps);
}
}
static void
itimer_start(void)
{
struct kclock rt_clock = {
.timer_create = realtimer_create,
.timer_delete = realtimer_delete,
.timer_settime = realtimer_settime,
.timer_gettime = realtimer_gettime,
.event_hook = NULL
};
itimer_zone = uma_zcreate("itimer", sizeof(struct itimer),
NULL, NULL, itimer_init, itimer_fini, UMA_ALIGN_PTR, 0);
register_posix_clock(CLOCK_REALTIME, &rt_clock);
register_posix_clock(CLOCK_MONOTONIC, &rt_clock);
p31b_setcfg(CTL_P1003_1B_TIMERS, 200112L);
p31b_setcfg(CTL_P1003_1B_DELAYTIMER_MAX, INT_MAX);
p31b_setcfg(CTL_P1003_1B_TIMER_MAX, TIMER_MAX);
EVENTHANDLER_REGISTER(process_exit, itimers_event_hook_exit,
(void *)ITIMER_EV_EXIT, EVENTHANDLER_PRI_ANY);
EVENTHANDLER_REGISTER(process_exec, itimers_event_hook_exec,
(void *)ITIMER_EV_EXEC, EVENTHANDLER_PRI_ANY);
}
int
register_posix_clock(int clockid, struct kclock *clk)
{
if ((unsigned)clockid >= MAX_CLOCKS) {
printf("%s: invalid clockid\n", __func__);
return (0);
}
posix_clocks[clockid] = *clk;
return (1);
}
static int
itimer_init(void *mem, int size, int flags)
{
struct itimer *it;
it = (struct itimer *)mem;
mtx_init(&it->it_mtx, "itimer lock", NULL, MTX_DEF);
return (0);
}
static void
itimer_fini(void *mem, int size)
{
struct itimer *it;
it = (struct itimer *)mem;
mtx_destroy(&it->it_mtx);
}
static void
itimer_enter(struct itimer *it)
{
mtx_assert(&it->it_mtx, MA_OWNED);
it->it_usecount++;
}
static void
itimer_leave(struct itimer *it)
{
mtx_assert(&it->it_mtx, MA_OWNED);
KASSERT(it->it_usecount > 0, ("invalid it_usecount"));
if (--it->it_usecount == 0 && (it->it_flags & ITF_WANTED) != 0)
wakeup(it);
}
#ifndef _SYS_SYSPROTO_H_
struct ktimer_create_args {
clockid_t clock_id;
struct sigevent * evp;
int * timerid;
};
#endif
int
ktimer_create(struct thread *td, struct ktimer_create_args *uap)
{
struct sigevent *evp1, ev;
int id;
int error;
if (uap->evp != NULL) {
error = copyin(uap->evp, &ev, sizeof(ev));
if (error != 0)
return (error);
evp1 = &ev;
} else
evp1 = NULL;
error = kern_timer_create(td, uap->clock_id, evp1, &id, -1);
if (error == 0) {
error = copyout(&id, uap->timerid, sizeof(int));
if (error != 0)
kern_timer_delete(td, id);
}
return (error);
}
static int
kern_timer_create(struct thread *td, clockid_t clock_id,
struct sigevent *evp, int *timerid, int preset_id)
{
struct proc *p = td->td_proc;
struct itimer *it;
int id;
int error;
if (clock_id < 0 || clock_id >= MAX_CLOCKS)
return (EINVAL);
if (posix_clocks[clock_id].timer_create == NULL)
return (EINVAL);
if (evp != NULL) {
if (evp->sigev_notify != SIGEV_NONE &&
evp->sigev_notify != SIGEV_SIGNAL &&
evp->sigev_notify != SIGEV_THREAD_ID)
return (EINVAL);
if ((evp->sigev_notify == SIGEV_SIGNAL ||
evp->sigev_notify == SIGEV_THREAD_ID) &&
!_SIG_VALID(evp->sigev_signo))
return (EINVAL);
}
if (p->p_itimers == NULL)
itimers_alloc(p);
it = uma_zalloc(itimer_zone, M_WAITOK);
it->it_flags = 0;
it->it_usecount = 0;
it->it_active = 0;
timespecclear(&it->it_time.it_value);
timespecclear(&it->it_time.it_interval);
it->it_overrun = 0;
it->it_overrun_last = 0;
it->it_clockid = clock_id;
it->it_timerid = -1;
it->it_proc = p;
ksiginfo_init(&it->it_ksi);
it->it_ksi.ksi_flags |= KSI_INS | KSI_EXT;
error = CLOCK_CALL(clock_id, timer_create, (it));
if (error != 0)
goto out;
PROC_LOCK(p);
if (preset_id != -1) {
KASSERT(preset_id >= 0 && preset_id < 3, ("invalid preset_id"));
id = preset_id;
if (p->p_itimers->its_timers[id] != NULL) {
PROC_UNLOCK(p);
error = 0;
goto out;
}
} else {
/*
* Find a free timer slot, skipping those reserved
* for setitimer().
*/
for (id = 3; id < TIMER_MAX; id++)
if (p->p_itimers->its_timers[id] == NULL)
break;
if (id == TIMER_MAX) {
PROC_UNLOCK(p);
error = EAGAIN;
goto out;
}
}
it->it_timerid = id;
p->p_itimers->its_timers[id] = it;
if (evp != NULL)
it->it_sigev = *evp;
else {
it->it_sigev.sigev_notify = SIGEV_SIGNAL;
switch (clock_id) {
default:
case CLOCK_REALTIME:
it->it_sigev.sigev_signo = SIGALRM;
break;
case CLOCK_VIRTUAL:
it->it_sigev.sigev_signo = SIGVTALRM;
break;
case CLOCK_PROF:
it->it_sigev.sigev_signo = SIGPROF;
break;
}
it->it_sigev.sigev_value.sival_int = id;
}
if (it->it_sigev.sigev_notify == SIGEV_SIGNAL ||
it->it_sigev.sigev_notify == SIGEV_THREAD_ID) {
it->it_ksi.ksi_signo = it->it_sigev.sigev_signo;
it->it_ksi.ksi_code = SI_TIMER;
it->it_ksi.ksi_value = it->it_sigev.sigev_value;
it->it_ksi.ksi_timerid = id;
}
PROC_UNLOCK(p);
*timerid = id;
return (0);
out:
ITIMER_LOCK(it);
CLOCK_CALL(it->it_clockid, timer_delete, (it));
ITIMER_UNLOCK(it);
uma_zfree(itimer_zone, it);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct ktimer_delete_args {
int timerid;
};
#endif
int
ktimer_delete(struct thread *td, struct ktimer_delete_args *uap)
{
return (kern_timer_delete(td, uap->timerid));
}
static struct itimer *
itimer_find(struct proc *p, int timerid)
{
struct itimer *it;
PROC_LOCK_ASSERT(p, MA_OWNED);
if ((p->p_itimers == NULL) || (timerid >= TIMER_MAX) ||
(it = p->p_itimers->its_timers[timerid]) == NULL) {
return (NULL);
}
ITIMER_LOCK(it);
if ((it->it_flags & ITF_DELETING) != 0) {
ITIMER_UNLOCK(it);
it = NULL;
}
return (it);
}
static int
kern_timer_delete(struct thread *td, int timerid)
{
struct proc *p = td->td_proc;
struct itimer *it;
PROC_LOCK(p);
it = itimer_find(p, timerid);
if (it == NULL) {
PROC_UNLOCK(p);
return (EINVAL);
}
PROC_UNLOCK(p);
it->it_flags |= ITF_DELETING;
while (it->it_usecount > 0) {
it->it_flags |= ITF_WANTED;
msleep(it, &it->it_mtx, PPAUSE, "itimer", 0);
}
it->it_flags &= ~ITF_WANTED;
CLOCK_CALL(it->it_clockid, timer_delete, (it));
ITIMER_UNLOCK(it);
PROC_LOCK(p);
if (KSI_ONQ(&it->it_ksi))
sigqueue_take(&it->it_ksi);
p->p_itimers->its_timers[timerid] = NULL;
PROC_UNLOCK(p);
uma_zfree(itimer_zone, it);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct ktimer_settime_args {
int timerid;
int flags;
const struct itimerspec * value;
struct itimerspec * ovalue;
};
#endif
int
ktimer_settime(struct thread *td, struct ktimer_settime_args *uap)
{
struct proc *p = td->td_proc;
struct itimer *it;
struct itimerspec val, oval, *ovalp;
int error;
error = copyin(uap->value, &val, sizeof(val));
if (error != 0)
return (error);
if (uap->ovalue != NULL)
ovalp = &oval;
else
ovalp = NULL;
PROC_LOCK(p);
if (uap->timerid < 3 ||
(it = itimer_find(p, uap->timerid)) == NULL) {
PROC_UNLOCK(p);
error = EINVAL;
} else {
PROC_UNLOCK(p);
itimer_enter(it);
error = CLOCK_CALL(it->it_clockid, timer_settime,
(it, uap->flags, &val, ovalp));
itimer_leave(it);
ITIMER_UNLOCK(it);
}
if (error == 0 && uap->ovalue != NULL)
error = copyout(ovalp, uap->ovalue, sizeof(*ovalp));
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct ktimer_gettime_args {
int timerid;
struct itimerspec * value;
};
#endif
int
ktimer_gettime(struct thread *td, struct ktimer_gettime_args *uap)
{
struct proc *p = td->td_proc;
struct itimer *it;
struct itimerspec val;
int error;
PROC_LOCK(p);
if (uap->timerid < 3 ||
(it = itimer_find(p, uap->timerid)) == NULL) {
PROC_UNLOCK(p);
error = EINVAL;
} else {
PROC_UNLOCK(p);
itimer_enter(it);
error = CLOCK_CALL(it->it_clockid, timer_gettime,
(it, &val));
itimer_leave(it);
ITIMER_UNLOCK(it);
}
if (error == 0)
error = copyout(&val, uap->value, sizeof(val));
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct timer_getoverrun_args {
int timerid;
};
#endif
int
ktimer_getoverrun(struct thread *td, struct ktimer_getoverrun_args *uap)
{
struct proc *p = td->td_proc;
struct itimer *it;
int error ;
PROC_LOCK(p);
if (uap->timerid < 3 ||
(it = itimer_find(p, uap->timerid)) == NULL) {
PROC_UNLOCK(p);
error = EINVAL;
} else {
td->td_retval[0] = it->it_overrun_last;
ITIMER_UNLOCK(it);
PROC_UNLOCK(p);
error = 0;
}
return (error);
}
static int
realtimer_create(struct itimer *it)
{
callout_init_mtx(&it->it_callout, &it->it_mtx, 0);
return (0);
}
static int
realtimer_delete(struct itimer *it)
{
mtx_assert(&it->it_mtx, MA_OWNED);
ITIMER_UNLOCK(it);
callout_drain(&it->it_callout);
ITIMER_LOCK(it);
return (0);
}
static int
realtimer_gettime(struct itimer *it, struct itimerspec *ovalue)
{
struct timespec cts;
mtx_assert(&it->it_mtx, MA_OWNED);
realtimer_clocktime(it->it_clockid, &cts);
*ovalue = it->it_time;
if (ovalue->it_value.tv_sec != 0 || ovalue->it_value.tv_nsec != 0) {
timespecsub(&ovalue->it_value, &cts);
if (ovalue->it_value.tv_sec < 0 ||
(ovalue->it_value.tv_sec == 0 &&
ovalue->it_value.tv_nsec == 0)) {
ovalue->it_value.tv_sec = 0;
ovalue->it_value.tv_nsec = 1;
}
}
return (0);
}
static int
realtimer_settime(struct itimer *it, int flags,
struct itimerspec *value, struct itimerspec *ovalue)
{
struct timespec cts, ts;
struct timeval tv;
struct itimerspec val;
mtx_assert(&it->it_mtx, MA_OWNED);
val = *value;
if (itimespecfix(&val.it_value))
return (EINVAL);
if (timespecisset(&val.it_value)) {
if (itimespecfix(&val.it_interval))
return (EINVAL);
} else {
timespecclear(&val.it_interval);
}
if (ovalue != NULL)
realtimer_gettime(it, ovalue);
it->it_time = val;
if (timespecisset(&val.it_value)) {
realtimer_clocktime(it->it_clockid, &cts);
ts = val.it_value;
if ((flags & TIMER_ABSTIME) == 0) {
/* Convert to absolute time. */
timespecadd(&it->it_time.it_value, &cts);
} else {
timespecsub(&ts, &cts);
/*
* We don't care if ts is negative, tztohz will
* fix it.
*/
}
TIMESPEC_TO_TIMEVAL(&tv, &ts);
callout_reset(&it->it_callout, tvtohz(&tv),
realtimer_expire, it);
} else {
callout_stop(&it->it_callout);
}
return (0);
}
static void
realtimer_clocktime(clockid_t id, struct timespec *ts)
{
if (id == CLOCK_REALTIME)
getnanotime(ts);
else /* CLOCK_MONOTONIC */
getnanouptime(ts);
}
int
itimer_accept(struct proc *p, int timerid, ksiginfo_t *ksi)
{
struct itimer *it;
PROC_LOCK_ASSERT(p, MA_OWNED);
it = itimer_find(p, timerid);
if (it != NULL) {
ksi->ksi_overrun = it->it_overrun;
it->it_overrun_last = it->it_overrun;
it->it_overrun = 0;
ITIMER_UNLOCK(it);
return (0);
}
return (EINVAL);
}
int
itimespecfix(struct timespec *ts)
{
if (ts->tv_sec < 0 || ts->tv_nsec < 0 || ts->tv_nsec >= 1000000000)
return (EINVAL);
if (ts->tv_sec == 0 && ts->tv_nsec != 0 && ts->tv_nsec < tick * 1000)
ts->tv_nsec = tick * 1000;
return (0);
}
/* Timeout callback for realtime timer */
static void
realtimer_expire(void *arg)
{
struct timespec cts, ts;
struct timeval tv;
struct itimer *it;
struct proc *p;
it = (struct itimer *)arg;
p = it->it_proc;
realtimer_clocktime(it->it_clockid, &cts);
/* Only fire if time is reached. */
if (timespeccmp(&cts, &it->it_time.it_value, >=)) {
if (timespecisset(&it->it_time.it_interval)) {
timespecadd(&it->it_time.it_value,
&it->it_time.it_interval);
while (timespeccmp(&cts, &it->it_time.it_value, >=)) {
if (it->it_overrun < INT_MAX)
it->it_overrun++;
else
it->it_ksi.ksi_errno = ERANGE;
timespecadd(&it->it_time.it_value,
&it->it_time.it_interval);
}
} else {
/* single shot timer ? */
timespecclear(&it->it_time.it_value);
}
if (timespecisset(&it->it_time.it_value)) {
ts = it->it_time.it_value;
timespecsub(&ts, &cts);
TIMESPEC_TO_TIMEVAL(&tv, &ts);
callout_reset(&it->it_callout, tvtohz(&tv),
realtimer_expire, it);
}
ITIMER_UNLOCK(it);
itimer_fire(it);
ITIMER_LOCK(it);
} else if (timespecisset(&it->it_time.it_value)) {
ts = it->it_time.it_value;
timespecsub(&ts, &cts);
TIMESPEC_TO_TIMEVAL(&tv, &ts);
callout_reset(&it->it_callout, tvtohz(&tv), realtimer_expire,
it);
}
}
void
itimer_fire(struct itimer *it)
{
struct proc *p = it->it_proc;
int ret;
if (it->it_sigev.sigev_notify == SIGEV_SIGNAL ||
it->it_sigev.sigev_notify == SIGEV_THREAD_ID) {
PROC_LOCK(p);
if (!KSI_ONQ(&it->it_ksi)) {
it->it_ksi.ksi_errno = 0;
ret = psignal_event(p, &it->it_sigev, &it->it_ksi);
if (__predict_false(ret != 0)) {
it->it_overrun++;
/*
* Broken userland code, thread went
* away, disarm the timer.
*/
if (ret == ESRCH) {
ITIMER_LOCK(it);
timespecclear(&it->it_time.it_value);
timespecclear(&it->it_time.it_interval);
callout_stop(&it->it_callout);
ITIMER_UNLOCK(it);
}
}
} else {
if (it->it_overrun < INT_MAX)
it->it_overrun++;
else
it->it_ksi.ksi_errno = ERANGE;
}
PROC_UNLOCK(p);
}
}
static void
itimers_alloc(struct proc *p)
{
struct itimers *its;
int i;
its = malloc(sizeof (struct itimers), M_SUBPROC, M_WAITOK | M_ZERO);
LIST_INIT(&its->its_virtual);
LIST_INIT(&its->its_prof);
TAILQ_INIT(&its->its_worklist);
for (i = 0; i < TIMER_MAX; i++)
its->its_timers[i] = NULL;
PROC_LOCK(p);
if (p->p_itimers == NULL) {
p->p_itimers = its;
PROC_UNLOCK(p);
}
else {
PROC_UNLOCK(p);
free(its, M_SUBPROC);
}
}
static void
itimers_event_hook_exec(void *arg, struct proc *p, struct image_params *imgp __unused)
{
itimers_event_hook_exit(arg, p);
}
/* Clean up timers when some process events are being triggered. */
static void
itimers_event_hook_exit(void *arg, struct proc *p)
{
struct itimers *its;
struct itimer *it;
int event = (int)(intptr_t)arg;
int i;
if (p->p_itimers != NULL) {
its = p->p_itimers;
for (i = 0; i < MAX_CLOCKS; ++i) {
if (posix_clocks[i].event_hook != NULL)
CLOCK_CALL(i, event_hook, (p, i, event));
}
/*
* According to susv3, XSI interval timers should be inherited
* by new image.
*/
if (event == ITIMER_EV_EXEC)
i = 3;
else if (event == ITIMER_EV_EXIT)
i = 0;
else
panic("unhandled event");
for (; i < TIMER_MAX; ++i) {
if ((it = its->its_timers[i]) != NULL)
kern_timer_delete(curthread, i);
}
if (its->its_timers[0] == NULL &&
its->its_timers[1] == NULL &&
its->its_timers[2] == NULL) {
free(its, M_SUBPROC);
p->p_itimers = NULL;
}
}
}