258 lines
6.4 KiB
C
258 lines
6.4 KiB
C
/*-
|
|
* Copyright (c) 2014 Poul-Henning Kamp
|
|
* 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
*
|
|
* UNIX timebase
|
|
* =============
|
|
*
|
|
* Implement the timebase functions on top of a modern UNIX kernel which
|
|
* has the some version of the Mills/Kamp kernel PLL code and either
|
|
* [gs]ettimeofday(2) or better: clock_[gs]ettime(2) API.
|
|
*
|
|
*/
|
|
|
|
#include "ntimed_platform.h"
|
|
#include "ntimed.h"
|
|
|
|
static double adj_offset = 0;
|
|
static double adj_duration = 0;
|
|
static double adj_freq = 0;
|
|
|
|
static uintptr_t ticker;
|
|
static struct todolist *kt_tdl;
|
|
|
|
// #undef CLOCK_REALTIME /* Test old unix code */
|
|
|
|
/**********************************************************************
|
|
* The NTP-pll in UNIX kernels apply the offset correction in an
|
|
* exponential-decay fashion for historical and wrong reasons.
|
|
*
|
|
* The short explanation is that this ends up confusing all PLLs I have
|
|
* ever seen, by introducing mainly odd harmonics of the PLL update period
|
|
* into all time-measurements in the system.
|
|
*
|
|
* A much more sane mode would be to tell the kernel "I want this much
|
|
* offset accumulated over this many seconds", giving a constant frequency
|
|
* over the PLL update period while still falling back to the frequency
|
|
* estimate should the time-steering userland process fail.
|
|
*
|
|
* I will add such a mode to the FreeBSD kernel as a reference implementation
|
|
* at a later date, in the mean time this code implements it by updating the
|
|
* kernel frequency from userland as needed.
|
|
*
|
|
* XXX: Optimise to only wake up when truly needed, rather than every second.
|
|
* XXX: Requires TODO cancellation.
|
|
*/
|
|
|
|
static void
|
|
kt_setfreq(struct ocx *ocx, double frequency)
|
|
{
|
|
/*
|
|
struct timex tx;
|
|
int i;
|
|
|
|
assert(isfinite(frequency));
|
|
|
|
memset(&tx, 0, sizeof tx);
|
|
tx.modes = MOD_STATUS;
|
|
#if defined(MOD_NANO)
|
|
tx.modes |= MOD_NANO;
|
|
#elif defined(MOD_MICRO)
|
|
tx.modes |= MOD_MICRO;
|
|
#endif
|
|
|
|
tx.status = STA_PLL | STA_FREQHOLD;
|
|
tx.modes = MOD_FREQUENCY;
|
|
tx.freq = (long)floor(frequency * (65536 * 1e6));
|
|
errno = 0;
|
|
i = ntp_adjtime(&tx);
|
|
*/
|
|
Put(ocx, OCX_TRACE, "KERNPLL %.6e %d\n", frequency, 0);
|
|
/* XXX: what is the correct error test here ? */
|
|
// assert(i >= 0);
|
|
}
|
|
|
|
static enum todo_e __match_proto__(todo_f)
|
|
kt_ticker(struct ocx *ocx, struct todolist *tdl, void *priv)
|
|
{
|
|
|
|
(void)ocx;
|
|
AN(tdl);
|
|
AZ(priv);
|
|
kt_setfreq(ocx, adj_freq);
|
|
ticker = 0;
|
|
return (TODO_OK);
|
|
}
|
|
|
|
static void __match_proto__(tb_adjust_f)
|
|
kt_adjust(struct ocx *ocx, double offset, double duration, double frequency)
|
|
{
|
|
double freq;
|
|
|
|
(void)ocx;
|
|
assert(duration >= 0.0);
|
|
|
|
if (ticker)
|
|
TODO_Cancel(kt_tdl, &ticker);
|
|
|
|
adj_offset = offset;
|
|
adj_duration = floor(duration);
|
|
if (adj_offset > 0.0 && adj_duration == 0.0)
|
|
adj_duration = 1.0;
|
|
adj_freq = frequency;
|
|
|
|
freq = adj_freq;
|
|
if (adj_duration > 0.0)
|
|
freq += adj_offset / adj_duration;
|
|
kt_setfreq(ocx, freq);
|
|
if (adj_duration > 0.0)
|
|
ticker = TODO_ScheduleRel(kt_tdl, kt_ticker, NULL,
|
|
adj_duration, 0.0, "KT_TICK");
|
|
}
|
|
|
|
/**********************************************************************/
|
|
|
|
#ifdef CLOCK_REALTIME
|
|
|
|
static void __match_proto__(tb_step_f)
|
|
kt_step(struct ocx *ocx, double offset)
|
|
{
|
|
double d;
|
|
struct timespec ts;
|
|
|
|
Put(ocx, OCX_TRACE, "KERNTIME_STEP %.3e\n", offset);
|
|
d = floor(offset);
|
|
offset -= d;
|
|
|
|
AZ(clock_gettime(CLOCK_REALTIME, &ts));
|
|
ts.tv_sec += (long)d;
|
|
ts.tv_nsec += (long)floor(offset * 1e9);
|
|
if (ts.tv_nsec < 0) {
|
|
ts.tv_sec -= 1;
|
|
ts.tv_nsec += 1000000000;
|
|
} else if (ts.tv_nsec >= 1000000000) {
|
|
ts.tv_sec += 1;
|
|
ts.tv_nsec -= 1000000000;
|
|
}
|
|
AZ(clock_settime(CLOCK_REALTIME, &ts));
|
|
TB_generation++;
|
|
}
|
|
|
|
#else
|
|
|
|
static void __match_proto__(tb_step_f)
|
|
kt_step(struct ocx *ocx, double offset)
|
|
{
|
|
double d;
|
|
struct timeval tv;
|
|
|
|
Put(ocx, OCX_TRACE, "KERNTIME_STEP %.3e\n", offset);
|
|
d = floor(offset);
|
|
offset -= d;
|
|
|
|
AZ(gettimeofday(&tv, NULL));
|
|
tv.tv_sec += (long)d;
|
|
tv.tv_usec += (long)floor(offset * 1e6);
|
|
if (tv.tv_usec < 0) {
|
|
tv.tv_sec -= 1;
|
|
tv.tv_usec += 1000000;
|
|
} else if (tv.tv_usec >= 1000000) {
|
|
tv.tv_sec += 1;
|
|
tv.tv_usec -= 1000000;
|
|
}
|
|
AZ(settimeofday(&tv, NULL));
|
|
TB_generation++;
|
|
}
|
|
|
|
#endif
|
|
|
|
/**********************************************************************/
|
|
|
|
#if defined (CLOCK_REALTIME)
|
|
|
|
static struct timestamp * __match_proto__(tb_now_f)
|
|
kt_now(struct timestamp *storage)
|
|
{
|
|
struct timespec ts;
|
|
|
|
AZ(clock_gettime(CLOCK_REALTIME, &ts));
|
|
return (TS_Nanosec(storage, ts.tv_sec, ts.tv_nsec));
|
|
}
|
|
|
|
#else
|
|
|
|
static struct timestamp * __match_proto__(tb_now_f)
|
|
kt_now(struct timestamp *storage)
|
|
{
|
|
struct timeval tv;
|
|
|
|
AZ(gettimeofday(&tv, NULL));
|
|
return (TS_Nanosec(storage, tv.tv_sec, tv.tv_usec * 1000LL));
|
|
}
|
|
|
|
#endif
|
|
|
|
/**********************************************************************/
|
|
|
|
static int __match_proto__(tb_sleep_f)
|
|
kt_sleep(double dur)
|
|
{
|
|
struct pollfd fds[1];
|
|
int i;
|
|
|
|
i = poll(fds, 0, (int)floor(dur * 1e3));
|
|
if (i < 0 && errno == EINTR)
|
|
return (1);
|
|
AZ(i);
|
|
return (0);
|
|
}
|
|
|
|
/**********************************************************************/
|
|
|
|
void
|
|
Time_Unix(struct todolist *tdl)
|
|
{
|
|
|
|
AN(tdl);
|
|
TB_Step = kt_step;
|
|
TB_Adjust = kt_adjust;
|
|
TB_Sleep = kt_sleep;
|
|
TB_Now = kt_now;
|
|
kt_tdl = tdl;
|
|
|
|
/* XXX: test if we have perms */
|
|
}
|
|
|
|
/**********************************************************************
|
|
* Non-tweaking subset.
|
|
*/
|
|
|
|
void
|
|
Time_Unix_Passive(void)
|
|
{
|
|
|
|
TB_Sleep = kt_sleep;
|
|
TB_Now = kt_now;
|
|
}
|