Now that the private parts of timecounters are no longer being fingered

by other bits of code, split struct timecounter into two.

struct timecounter contains just the bits which pertains to the hardware
counter and the reading of it.

struct timehands (as in "the hands on a clock") contains all the ugly bit
fidling stuff.  Statically compile ten timehands.

This commit is the functional part.  A later cosmetic patch will rename
various variables and fieldnames.
This commit is contained in:
Poul-Henning Kamp 2002-04-26 21:51:08 +00:00
parent b4a1d0deb1
commit 62efba6a0c
3 changed files with 113 additions and 156 deletions

View File

@ -13,7 +13,6 @@
#include <sys/param.h>
#include <sys/timetc.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
@ -21,14 +20,58 @@
#include <sys/timepps.h>
/*
* Number of timecounters used to implement stable storage
* Implement a dummy timecounter which we can use until we get a real one
* in the air. This allows the console and other early stuff to use
* timeservices.
*/
#ifndef NTIMECOUNTER
#define NTIMECOUNTER hz
#endif
static MALLOC_DEFINE(M_TIMECOUNTER, "timecounter",
"Timecounter stable storage");
static unsigned
dummy_get_timecount(struct timecounter *tc)
{
static unsigned now;
return (++now);
}
static struct timecounter dummy_timecounter = {
dummy_get_timecount,
0,
~0u,
1000000,
"dummy"
};
struct timehands {
/* These fields must be initialized by the driver. */
struct timecounter *tc_counter;
int64_t tc_adjustment;
u_int64_t tc_scale;
unsigned tc_offset_count;
struct bintime tc_offset;
struct timeval tc_microtime;
struct timespec tc_nanotime;
/* Fields not to be copied in tc_windup start with tc_generation */
volatile unsigned tc_generation;
struct timehands *tc_next;
};
extern struct timehands th0;
static struct timehands th9 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th0};
static struct timehands th8 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th9};
static struct timehands th7 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th8};
static struct timehands th6 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th7};
static struct timehands th5 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th6};
static struct timehands th4 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th5};
static struct timehands th3 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th4};
static struct timehands th2 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th3};
static struct timehands th1 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th2};
static struct timehands th0 =
{ &dummy_timecounter, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 1, &th1};
static struct timehands *volatile timehands = &th0;
struct timecounter *timecounter = &dummy_timecounter;
static struct timecounter *timecounters = &dummy_timecounter;
time_t time_second;
@ -52,49 +95,24 @@ TC_STATS(ngetbintime); TC_STATS(ngetnanotime); TC_STATS(ngetmicrotime);
static void tc_windup(void);
/*
* Implement a dummy timecounter which we can use until we get a real one
* in the air. This allows the console and other early stuff to use
* timeservices.
*/
static unsigned
dummy_get_timecount(struct timecounter *tc)
{
static unsigned now;
if (tc->tc_generation == 0)
tc->tc_generation = 1;
return (++now);
}
static struct timecounter dummy_timecounter = {
dummy_get_timecount,
0,
~0u,
1000000,
"dummy"
};
struct timecounter *volatile timecounter = &dummy_timecounter;
static __inline unsigned
tc_delta(struct timecounter *tc)
tc_delta(struct timehands *tc)
{
return ((tc->tc_get_timecount(tc) - tc->tc_offset_count) &
tc->tc_counter_mask);
return ((tc->tc_counter->tc_get_timecount(tc->tc_counter) -
tc->tc_offset_count) & tc->tc_counter->tc_counter_mask);
}
void
binuptime(struct bintime *bt)
{
struct timecounter *tc;
struct timehands *tc;
unsigned gen;
nbinuptime++;
do {
tc = timecounter;
tc = timehands;
gen = tc->tc_generation;
*bt = tc->tc_offset;
bintime_addx(bt, tc->tc_scale * tc_delta(tc));
@ -153,12 +171,12 @@ microtime(struct timeval *tv)
void
getbinuptime(struct bintime *bt)
{
struct timecounter *tc;
struct timehands *tc;
unsigned gen;
ngetbinuptime++;
do {
tc = timecounter;
tc = timehands;
gen = tc->tc_generation;
*bt = tc->tc_offset;
} while (gen == 0 || gen != tc->tc_generation);
@ -167,12 +185,12 @@ getbinuptime(struct bintime *bt)
void
getnanouptime(struct timespec *tsp)
{
struct timecounter *tc;
struct timehands *tc;
unsigned gen;
ngetnanouptime++;
do {
tc = timecounter;
tc = timehands;
gen = tc->tc_generation;
bintime2timespec(&tc->tc_offset, tsp);
} while (gen == 0 || gen != tc->tc_generation);
@ -181,12 +199,12 @@ getnanouptime(struct timespec *tsp)
void
getmicrouptime(struct timeval *tvp)
{
struct timecounter *tc;
struct timehands *tc;
unsigned gen;
ngetmicrouptime++;
do {
tc = timecounter;
tc = timehands;
gen = tc->tc_generation;
bintime2timeval(&tc->tc_offset, tvp);
} while (gen == 0 || gen != tc->tc_generation);
@ -195,12 +213,12 @@ getmicrouptime(struct timeval *tvp)
void
getbintime(struct bintime *bt)
{
struct timecounter *tc;
struct timehands *tc;
unsigned gen;
ngetbintime++;
do {
tc = timecounter;
tc = timehands;
gen = tc->tc_generation;
*bt = tc->tc_offset;
} while (gen == 0 || gen != tc->tc_generation);
@ -210,12 +228,12 @@ getbintime(struct bintime *bt)
void
getnanotime(struct timespec *tsp)
{
struct timecounter *tc;
struct timehands *tc;
unsigned gen;
ngetnanotime++;
do {
tc = timecounter;
tc = timehands;
gen = tc->tc_generation;
*tsp = tc->tc_nanotime;
} while (gen == 0 || gen != tc->tc_generation);
@ -224,19 +242,19 @@ getnanotime(struct timespec *tsp)
void
getmicrotime(struct timeval *tvp)
{
struct timecounter *tc;
struct timehands *tc;
unsigned gen;
ngetmicrotime++;
do {
tc = timecounter;
tc = timehands;
gen = tc->tc_generation;
*tvp = tc->tc_microtime;
} while (gen == 0 || gen != tc->tc_generation);
}
static void
tc_setscales(struct timecounter *tc)
tc_setscales(struct timehands *tc)
{
u_int64_t scale;
@ -250,49 +268,26 @@ tc_setscales(struct timecounter *tc)
* Divide by 2 times 512 to match the temporary lower precision.
*/
scale += (tc->tc_adjustment / 1024) * 2199;
scale /= tc->tc_tweak->tc_frequency;
scale /= tc->tc_counter->tc_frequency;
tc->tc_scale = scale * 2;
}
void
tc_init(struct timecounter *tc)
{
struct timecounter *t1, *t2, *t3;
int i;
tc->tc_adjustment = 0;
tc->tc_tweak = tc;
tc_setscales(tc);
tc->tc_offset_count = tc->tc_get_timecount(tc);
if (timecounter == &dummy_timecounter)
tc->tc_avail = tc;
else {
tc->tc_avail = timecounter->tc_tweak->tc_avail;
timecounter->tc_tweak->tc_avail = tc;
}
MALLOC(t1, struct timecounter *, sizeof *t1, M_TIMECOUNTER, M_WAITOK | M_ZERO);
tc->tc_next = t1;
*t1 = *tc;
t2 = t1;
t3 = NULL;
for (i = 1; i < NTIMECOUNTER; i++) {
MALLOC(t3, struct timecounter *, sizeof *t3,
M_TIMECOUNTER, M_WAITOK | M_ZERO);
*t3 = *tc;
t3->tc_next = t2;
t2 = t3;
}
t1->tc_next = t3;
tc = t1;
tc->tc_next = timecounters;
timecounters = tc;
printf("Timecounter \"%s\" frequency %lu Hz\n",
tc->tc_name, (u_long)tc->tc_frequency);
/* XXX: For now always start using the counter. */
tc->tc_offset_count = tc->tc_get_timecount(tc);
binuptime(&tc->tc_offset);
timecounter = tc;
tc_windup();
}
u_int32_t
tc_getfrequency(void)
{
return (timehands->tc_counter->tc_frequency);
}
void
@ -312,51 +307,25 @@ tc_setclock(struct timespec *ts)
tc_windup();
}
u_int32_t
tc_getfrequency(void)
{
return (timecounter->tc_frequency);
}
static void
switch_timecounter(struct timecounter *newtc)
{
int s;
struct timecounter *tc;
s = splclock();
tc = timecounter;
if (newtc->tc_tweak == tc->tc_tweak) {
splx(s);
return;
}
newtc = newtc->tc_tweak->tc_next;
binuptime(&newtc->tc_offset);
newtc->tc_offset_count = newtc->tc_get_timecount(newtc);
tc_setscales(newtc);
newtc->tc_generation = 0;
timecounter = newtc;
tc_windup();
splx(s);
}
static void
tc_windup(void)
{
struct timecounter *tc, *tco;
struct timehands *tc, *tco;
struct bintime bt;
unsigned ogen, delta;
unsigned ogen, delta, ncount;
int i;
tco = timecounter;
ncount = 0; /* GCC is lame */
tco = timehands;
tc = tco->tc_next;
ogen = tc->tc_generation;
tc->tc_generation = 0;
bcopy(tco, tc, __offsetof(struct timecounter, tc_generation));
bcopy(tco, tc, __offsetof(struct timehands, tc_generation));
delta = tc_delta(tc);
if (tc->tc_counter != timecounter)
ncount = timecounter->tc_get_timecount(timecounter);
tc->tc_offset_count += delta;
tc->tc_offset_count &= tc->tc_counter_mask;
tc->tc_offset_count &= tc->tc_counter->tc_counter_mask;
bintime_addx(&tc->tc_offset, tc->tc_scale * delta);
/*
* We may be inducing a tiny error here, the tc_poll_pps() may
@ -367,8 +336,8 @@ tc_windup(void)
* going to be only a few weenieseconds (as Dave Mills would
* say), so lets just not talk more about it, OK ?
*/
if (tco->tc_poll_pps)
tco->tc_poll_pps(tco);
if (tco->tc_counter->tc_poll_pps)
tco->tc_counter->tc_poll_pps(tco->tc_counter);
for (i = tc->tc_offset.sec - tco->tc_offset.sec; i > 0; i--)
ntp_update_second(&tc->tc_adjustment, &tc->tc_offset.sec);
tc_setscales(tc);
@ -382,7 +351,7 @@ tc_windup(void)
ogen++;
tc->tc_generation = ogen;
time_second = tc->tc_microtime.tv_sec;
timecounter = tc;
timehands = tc;
}
static int
@ -392,24 +361,21 @@ sysctl_kern_timecounter_hardware(SYSCTL_HANDLER_ARGS)
struct timecounter *newtc, *tc;
int error;
tc = timecounter->tc_tweak;
tc = timecounter;
strncpy(newname, tc->tc_name, sizeof(newname));
error = sysctl_handle_string(oidp, &newname[0], sizeof(newname), req);
if (error == 0 && req->newptr != NULL &&
strcmp(newname, tc->tc_name) != 0) {
for (newtc = tc->tc_avail; newtc != tc;
newtc = newtc->tc_avail) {
if (strcmp(newname, newtc->tc_name) == 0) {
/* Warm up new timecounter. */
(void)newtc->tc_get_timecount(newtc);
switch_timecounter(newtc);
return (0);
}
}
return (EINVAL);
if (error != 0 && req->newptr == NULL && !strcmp(newname, tc->tc_name))
return(error);
for (newtc = timecounters; newtc != NULL; newtc = newtc->tc_next) {
if (strcmp(newname, newtc->tc_name))
continue;
/* Warm up new timecounter. */
(void)newtc->tc_get_timecount(newtc);
(void)newtc->tc_get_timecount(newtc);
timecounter = newtc;
return (0);
}
return (error);
return (EINVAL);
}
SYSCTL_PROC(_kern_timecounter, OID_AUTO, hardware, CTLTYPE_STRING | CTLFLAG_RW,
@ -486,12 +452,12 @@ pps_init(struct pps_state *pps)
void
pps_capture(struct pps_state *pps)
{
struct timecounter *tc;
struct timehands *tc;
tc = timecounter;
tc = timehands;
pps->captc = tc;
pps->capgen = tc->tc_generation;
pps->capcount = tc->tc_get_timecount(tc);
pps->capcount = tc->tc_counter->tc_get_timecount(tc->tc_counter);
}
void
@ -526,9 +492,9 @@ pps_event(struct pps_state *pps, int event)
/* The timecounter changed: bail */
if (!pps->ppstc ||
pps->ppstc->tc_name != pps->captc->tc_name ||
pps->captc->tc_name != timecounter->tc_name) {
pps->ppstc = pps->captc;
pps->ppstc != pps->captc->tc_counter ||
pps->captc->tc_counter != timehands->tc_counter) {
pps->ppstc = pps->captc->tc_counter;
*pcount = pps->capcount;
#ifdef PPS_SYNC
pps->ppscount[2] = pps->capcount;
@ -542,7 +508,7 @@ pps_event(struct pps_state *pps, int event)
/* Convert the count to timespec */
tcount = pps->capcount - pps->captc->tc_offset_count;
tcount &= pps->captc->tc_counter_mask;
tcount &= pps->captc->tc_counter->tc_counter_mask;
bt = pps->captc->tc_offset;
bintime_addx(&bt, pps->captc->tc_scale * tcount);
bintime2timespec(&bt, &ts);
@ -567,7 +533,7 @@ pps_event(struct pps_state *pps, int event)
/* magic, at its best... */
tcount = pps->capcount - pps->ppscount[2];
pps->ppscount[2] = pps->capcount;
tcount &= pps->captc->tc_counter_mask;
tcount &= pps->captc->tc_counter->tc_counter_mask;
bt.sec = 0;
bt.frac = 0;
bintime_addx(&bt, pps->captc->tc_scale * tcount);

View File

@ -103,9 +103,11 @@ struct pps_kcbind_args {
#define PPS_IOC_KCBIND _IOW('1', 7, struct pps_kcbind_args)
#ifdef _KERNEL
struct timehands;
struct timecounter;
struct pps_state {
/* capture information */
struct timecounter *captc;
struct timehands *captc;
u_int capgen;
u_int capcount;
/* state information */

View File

@ -76,22 +76,11 @@ struct timecounter {
u_int32_t tc_frequency;
char *tc_name;
void *tc_priv;
/* These fields will be managed by the generic code. */
int64_t tc_adjustment;
u_int64_t tc_scale;
unsigned tc_offset_count;
struct bintime tc_offset;
struct timeval tc_microtime;
struct timespec tc_nanotime;
struct timecounter *tc_avail;
struct timecounter *tc_tweak;
/* Fields not to be copied in tc_windup start with tc_generation */
volatile unsigned tc_generation;
struct timecounter *tc_next;
};
#ifdef _KERNEL
extern struct timecounter *volatile timecounter;
extern struct timecounter *timecounter;
u_int32_t tc_getfrequency(void);
void tc_init(struct timecounter *tc);