/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <sys/fm/protocol.h>
#include <signal.h>
#include <limits.h>
#include <time.h>
#include <fmd_time.h>
#include <fmd_alloc.h>
#include <fmd_error.h>
#include <fmd_subr.h>
#include <fmd.h>
void
fmd_time_gettimeofday(struct timeval *tvp)
{
if (fmd.d_clockops->fto_gettimeofday(tvp, NULL) != 0)
fmd_panic("failed to read time-of-day clock");
}
hrtime_t
fmd_time_gethrtime(void)
{
return (fmd.d_clockops->fto_gethrtime());
}
void
fmd_time_addhrtime(hrtime_t delta)
{
fmd.d_clockops->fto_addhrtime(delta);
}
void
fmd_time_waithrtime(hrtime_t delta)
{
fmd.d_clockops->fto_waithrtime(delta);
}
void
fmd_time_waitcancel(pthread_t tid)
{
fmd.d_clockops->fto_waitcancel(tid);
}
/*
* To synchronize TOD with a gethrtime() source, we repeatedly sample TOD in
* between two calls to gethrtime(), which places a reasonably tight bound on
* the high-resolution time that matches the TOD value we sampled. We repeat
* this process several times and ultimately select the sample where the two
* values of gethrtime() were closest. We then assign the average of those
* two high-resolution times to be the gethrtime() associated with that TOD.
*/
void
fmd_time_sync(fmd_timeval_t *ftv, hrtime_t *hrp, uint_t samples)
{
const fmd_timeops_t *ftop = fmd.d_clockops;
hrtime_t hrtbase, hrtmin = INT64_MAX;
struct timeval todbase;
uint_t i;
for (i = 0; i < samples; i++) {
hrtime_t t0, t1, delta;
struct timeval tod;
t0 = ftop->fto_gethrtime();
(void) ftop->fto_gettimeofday(&tod, NULL);
t1 = ftop->fto_gethrtime();
delta = t1 - t0;
if (delta < hrtmin) {
hrtmin = delta;
hrtbase = t0 + delta / 2;
todbase = tod;
}
}
if (ftv != NULL) {
ftv->ftv_sec = todbase.tv_sec;
ftv->ftv_nsec = todbase.tv_usec * (NANOSEC / MICROSEC);
}
if (hrp != NULL)
*hrp = hrtbase;
}
/*
* Convert a high-resolution timestamp into 64-bit seconds and nanoseconds.
* For efficiency, the multiplication and division are expanded using the
* clever algorithm originally designed for the kernel in hrt2ts(). Refer to
* the comments in uts/common/os/timers.c for an explanation of how it works.
*/
static void
fmd_time_hrt2ftv(hrtime_t hrt, fmd_timeval_t *ftv)
{
uint32_t sec, nsec, tmp;
tmp = (uint32_t)(hrt >> 30);
sec = tmp - (tmp >> 2);
sec = tmp - (sec >> 5);
sec = tmp + (sec >> 1);
sec = tmp - (sec >> 6) + 7;
sec = tmp - (sec >> 3);
sec = tmp + (sec >> 1);
sec = tmp + (sec >> 3);
sec = tmp + (sec >> 4);
tmp = (sec << 7) - sec - sec - sec;
tmp = (tmp << 7) - tmp - tmp - tmp;
tmp = (tmp << 7) - tmp - tmp - tmp;
nsec = (uint32_t)hrt - (tmp << 9);
while (nsec >= NANOSEC) {
nsec -= NANOSEC;
sec++;
}
ftv->ftv_sec = sec;
ftv->ftv_nsec = nsec;
}
/*
* Convert a high-resolution time from gethrtime() to a TOD (fmd_timeval_t).
* We convert 'tod_base' to nanoseconds, adjust it based on the difference
* between the corresponding 'hrt_base' and the event high-res time 'hrt',
* and then repack the result into ftv_sec and ftv_nsec for our output.
*/
void
fmd_time_hrt2tod(hrtime_t hrt_base, const fmd_timeval_t *tod_base,
hrtime_t hrt, fmd_timeval_t *ftv)
{
fmd_time_hrt2ftv(tod_base->ftv_sec * NANOSEC +
tod_base->ftv_nsec + (hrt - hrt_base), ftv);
}
/*
* Convert a TOD (fmd_timeval_t) to a high-resolution time from gethrtime().
* Note that since TOD occurred in the past, the resulting value may be a
* negative number according the current gethrtime() clock value.
*/
void
fmd_time_tod2hrt(hrtime_t hrt_base, const fmd_timeval_t *tod_base,
const fmd_timeval_t *ftv, hrtime_t *hrtp)
{
hrtime_t tod_hrt = tod_base->ftv_sec * NANOSEC + tod_base->ftv_nsec;
hrtime_t ftv_hrt = ftv->ftv_sec * NANOSEC + ftv->ftv_nsec;
*hrtp = hrt_base - (tod_hrt - ftv_hrt);
}
/*
* Adjust a high-resolution time based on the low bits of time stored in ENA.
* The assumption here in that ENA won't wrap between the time it is computed
* and the time the error is queued (when we capture a full 64-bits of hrtime).
* We extract the relevant ENA time bits as 't0' and subtract the difference
* between these bits and the corresponding low bits of 'hrt' from 'hrt'.
*
* Under xVM dom0, the UE ereport is prepared after panic, therefore
* the full 64-bit hrtime of 't0' can be bigger than 'hrt'. In such case,
* we should just return 'hrt'.
*
* 't0' contains only the low bits of 64bit hrtime. It is tricky to tell
* whether 'hrt' or 't0' happened first. We assume there should be short
* period between 'hrt' and 't0', therefore to check which one came first, we
* test their subtraction against the highest bit of mask, if the bit is not
* set, then 't0' is earlier. This is equivalent to
* ((hrt - t0) & mask) < ((mask + 1) / 2)
*/
hrtime_t
fmd_time_ena2hrt(hrtime_t hrt, uint64_t ena)
{
hrtime_t t0, mask;
switch (ENA_FORMAT(ena)) {
case FM_ENA_FMT1:
t0 = (ena & ENA_FMT1_TIME_MASK) >> ENA_FMT1_TIME_SHFT;
mask = ENA_FMT1_TIME_MASK >> ENA_FMT1_TIME_SHFT;
if (((hrt - t0) & ((mask + 1) >> 1)) == 0)
hrt -= (hrt - t0) & mask;
break;
case FM_ENA_FMT2:
t0 = (ena & ENA_FMT2_TIME_MASK) >> ENA_FMT2_TIME_SHFT;
mask = ENA_FMT2_TIME_MASK >> ENA_FMT2_TIME_SHFT;
if (((hrt - t0) & ((mask + 1) >> 1)) == 0)
hrt -= (hrt - t0) & mask;
break;
}
return (hrt);
}
/*
* To implement a simulated clock, we keep track of an hrtime_t value which
* starts at zero and is incremented only by fmd_time_addhrtime() (i.e. when
* the driver of the simulation requests that the clock advance). We sample
* the native time-of-day clock once at the start of the simulation and then
* return subsequent time-of-day values by adjusting TOD using the hrtime_t
* clock setting. Simulated nanosleep (fmd_time_waithrtime() entry point) is
* implemented by waiting on fts->fts_cv for the hrtime_t to increment.
*/
static void *
fmd_simulator_init(void)
{
fmd_timesim_t *fts = fmd_alloc(sizeof (fmd_timesim_t), FMD_SLEEP);
struct timeval tv;
(void) pthread_mutex_init(&fts->fts_lock, NULL);
(void) pthread_cond_init(&fts->fts_cv, NULL);
(void) gettimeofday(&tv, NULL);
fts->fts_tod = (hrtime_t)tv.tv_sec * NANOSEC +
(hrtime_t)tv.tv_usec * (NANOSEC / MICROSEC);
fts->fts_hrt = 0;
fts->fts_cancel = 0;
fmd_dprintf(FMD_DBG_TMR, "simulator tod base tv_sec=%lx hrt=%llx\n",
tv.tv_sec, fts->fts_tod);
return (fts);
}
static void
fmd_simulator_fini(void *fts)
{
if (fts != NULL)
fmd_free(fts, sizeof (fmd_timesim_t));
}
/*ARGSUSED*/
static int
fmd_simulator_tod(struct timeval *tvp, void *tzp)
{
fmd_timesim_t *fts = fmd.d_clockptr;
hrtime_t tod, hrt, sec, rem;
(void) pthread_mutex_lock(&fts->fts_lock);
tod = fts->fts_tod;
hrt = fts->fts_hrt;
(void) pthread_mutex_unlock(&fts->fts_lock);
sec = tod / NANOSEC + hrt / NANOSEC;
rem = tod % NANOSEC + hrt % NANOSEC;
tvp->tv_sec = sec + rem / NANOSEC;
tvp->tv_usec = (rem % NANOSEC) / (NANOSEC / MICROSEC);
return (0);
}
static hrtime_t
fmd_simulator_hrt(void)
{
fmd_timesim_t *fts = fmd.d_clockptr;
hrtime_t hrt;
(void) pthread_mutex_lock(&fts->fts_lock);
hrt = fts->fts_hrt;
(void) pthread_mutex_unlock(&fts->fts_lock);
return (hrt);
}
static void
fmd_simulator_add(hrtime_t delta)
{
fmd_timesim_t *fts = fmd.d_clockptr;
(void) pthread_mutex_lock(&fts->fts_lock);
if (fts->fts_hrt + delta < fts->fts_hrt)
fts->fts_hrt = INT64_MAX; /* do not increment past apocalypse */
else
fts->fts_hrt += delta;
TRACE((FMD_DBG_TMR, "hrt clock set %llx", fts->fts_hrt));
fmd_dprintf(FMD_DBG_TMR, "hrt clock set %llx\n", fts->fts_hrt);
(void) pthread_cond_broadcast(&fts->fts_cv);
(void) pthread_mutex_unlock(&fts->fts_lock);
}
static void
fmd_simulator_wait(hrtime_t delta)
{
fmd_timesim_t *fts = fmd.d_clockptr;
uint64_t hrt;
(void) pthread_mutex_lock(&fts->fts_lock);
/*
* If the delta causes time to wrap because we've reached the simulated
* apocalypse, then wait forever. We make 'hrt' unsigned so that the
* while-loop comparison fts_hrt < UINT64_MAX will always return true.
*/
if (fts->fts_hrt + delta < fts->fts_hrt)
hrt = UINT64_MAX;
else
hrt = fts->fts_hrt + delta;
while (fts->fts_hrt < hrt && fts->fts_cancel == 0)
(void) pthread_cond_wait(&fts->fts_cv, &fts->fts_lock);
if (fts->fts_cancel != 0)
fts->fts_cancel--; /* cancel has been processed */
(void) pthread_mutex_unlock(&fts->fts_lock);
}
/*ARGSUSED*/
static void
fmd_simulator_cancel(pthread_t tid)
{
fmd_timesim_t *fts = fmd.d_clockptr;
(void) pthread_mutex_lock(&fts->fts_lock);
fts->fts_cancel++;
(void) pthread_cond_signal(&fts->fts_cv);
(void) pthread_mutex_unlock(&fts->fts_lock);
}
/*
* Native time is implemented by calls to gethrtime() and gettimeofday(), which
* are stored directly in the native time ops-vector defined below. To wait on
* the native clock we use nanosleep(), which we can abort using a signal. The
* implementation assumes that callers will have a SIGALRM handler installed.
*/
static void
fmd_native_wait(hrtime_t delta)
{
timespec_t tv;
tv.tv_sec = delta / NANOSEC;
tv.tv_nsec = delta % NANOSEC;
(void) nanosleep(&tv, NULL);
}
static void
fmd_native_cancel(pthread_t tid)
{
(void) pthread_kill(tid, SIGALRM);
}
static void *
fmd_time_nop(void)
{
return (NULL);
}
const fmd_timeops_t fmd_timeops_native = {
(void *(*)())fmd_time_nop, /* fto_init */
(void (*)())fmd_time_nop, /* fto_fini */
gettimeofday, /* fto_gettimeofday */
gethrtime, /* fto_gethrtime */
(void (*)())fmd_time_nop, /* fto_addhrtime */
fmd_native_wait, /* fto_waithrtime */
fmd_native_cancel, /* fto_waitcancel */
};
const fmd_timeops_t fmd_timeops_simulated = {
fmd_simulator_init, /* fto_init */
fmd_simulator_fini, /* fto_fini */
fmd_simulator_tod, /* fto_gettimeofday */
fmd_simulator_hrt, /* fto_gethrtime */
fmd_simulator_add, /* fto_addhrtime */
fmd_simulator_wait, /* fto_waithrtime */
fmd_simulator_cancel, /* fto_waitcancel */
};