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FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //sys/kern/kern_clocksource.c |
/*-
* Copyright (c) 2010-2012 Alexander Motin <mav@FreeBSD.org>
* 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,
* without modification, immediately at the beginning of the file.
* 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 ``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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/sys/kern/kern_clocksource.c 234167 2012-04-12 06:29:02Z mav $");
/*
* Common routines to manage event timers hardware.
*/
#include "opt_device_polling.h"
#include "opt_kdtrace.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/lock.h>
#include <sys/kdb.h>
#include <sys/ktr.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/kernel.h>
#include <sys/sched.h>
#include <sys/smp.h>
#include <sys/sysctl.h>
#include <sys/timeet.h>
#include <sys/timetc.h>
#include <machine/atomic.h>
#include <machine/clock.h>
#include <machine/cpu.h>
#include <machine/smp.h>
#ifdef KDTRACE_HOOKS
#include <sys/dtrace_bsd.h>
cyclic_clock_func_t cyclic_clock_func = NULL;
#endif
int cpu_can_deep_sleep = 0; /* C3 state is available. */
int cpu_disable_deep_sleep = 0; /* Timer dies in C3. */
static void setuptimer(void);
static void loadtimer(struct bintime *now, int first);
static int doconfigtimer(void);
static void configtimer(int start);
static int round_freq(struct eventtimer *et, int freq);
static void getnextcpuevent(struct bintime *event, int idle);
static void getnextevent(struct bintime *event);
static int handleevents(struct bintime *now, int fake);
#ifdef SMP
static void cpu_new_callout(int cpu, int ticks);
#endif
static struct mtx et_hw_mtx;
#define ET_HW_LOCK(state) \
{ \
if (timer->et_flags & ET_FLAGS_PERCPU) \
mtx_lock_spin(&(state)->et_hw_mtx); \
else \
mtx_lock_spin(&et_hw_mtx); \
}
#define ET_HW_UNLOCK(state) \
{ \
if (timer->et_flags & ET_FLAGS_PERCPU) \
mtx_unlock_spin(&(state)->et_hw_mtx); \
else \
mtx_unlock_spin(&et_hw_mtx); \
}
static struct eventtimer *timer = NULL;
static struct bintime timerperiod; /* Timer period for periodic mode. */
static struct bintime hardperiod; /* hardclock() events period. */
static struct bintime statperiod; /* statclock() events period. */
static struct bintime profperiod; /* profclock() events period. */
static struct bintime nexttick; /* Next global timer tick time. */
static struct bintime nexthard; /* Next global hardlock() event. */
static u_int busy = 0; /* Reconfiguration is in progress. */
static int profiling = 0; /* Profiling events enabled. */
static char timername[32]; /* Wanted timer. */
TUNABLE_STR("kern.eventtimer.timer", timername, sizeof(timername));
static int singlemul = 0; /* Multiplier for periodic mode. */
TUNABLE_INT("kern.eventtimer.singlemul", &singlemul);
SYSCTL_INT(_kern_eventtimer, OID_AUTO, singlemul, CTLFLAG_RW, &singlemul,
0, "Multiplier for periodic mode");
static u_int idletick = 0; /* Run periodic events when idle. */
TUNABLE_INT("kern.eventtimer.idletick", &idletick);
SYSCTL_UINT(_kern_eventtimer, OID_AUTO, idletick, CTLFLAG_RW, &idletick,
0, "Run periodic events when idle");
static u_int activetick = 1; /* Run all periodic events when active. */
TUNABLE_INT("kern.eventtimer.activetick", &activetick);
SYSCTL_UINT(_kern_eventtimer, OID_AUTO, activetick, CTLFLAG_RW, &activetick,
0, "Run all periodic events when active");
static int periodic = 0; /* Periodic or one-shot mode. */
static int want_periodic = 0; /* What mode to prefer. */
TUNABLE_INT("kern.eventtimer.periodic", &want_periodic);
struct pcpu_state {
struct mtx et_hw_mtx; /* Per-CPU timer mutex. */
u_int action; /* Reconfiguration requests. */
u_int handle; /* Immediate handle resuests. */
struct bintime now; /* Last tick time. */
struct bintime nextevent; /* Next scheduled event on this CPU. */
struct bintime nexttick; /* Next timer tick time. */
struct bintime nexthard; /* Next hardlock() event. */
struct bintime nextstat; /* Next statclock() event. */
struct bintime nextprof; /* Next profclock() event. */
#ifdef KDTRACE_HOOKS
struct bintime nextcyc; /* Next OpenSolaris cyclics event. */
#endif
int ipi; /* This CPU needs IPI. */
int idle; /* This CPU is in idle mode. */
};
static DPCPU_DEFINE(struct pcpu_state, timerstate);
#define FREQ2BT(freq, bt) \
{ \
(bt)->sec = 0; \
(bt)->frac = ((uint64_t)0x8000000000000000 / (freq)) << 1; \
}
#define BT2FREQ(bt) \
(((uint64_t)0x8000000000000000 + ((bt)->frac >> 2)) / \
((bt)->frac >> 1))
/*
* Timer broadcast IPI handler.
*/
int
hardclockintr(void)
{
struct bintime now;
struct pcpu_state *state;
int done;
if (doconfigtimer() || busy)
return (FILTER_HANDLED);
state = DPCPU_PTR(timerstate);
now = state->now;
CTR4(KTR_SPARE2, "ipi at %d: now %d.%08x%08x",
curcpu, now.sec, (unsigned int)(now.frac >> 32),
(unsigned int)(now.frac & 0xffffffff));
done = handleevents(&now, 0);
return (done ? FILTER_HANDLED : FILTER_STRAY);
}
/*
* Handle all events for specified time on this CPU
*/
static int
handleevents(struct bintime *now, int fake)
{
struct bintime t;
struct trapframe *frame;
struct pcpu_state *state;
uintfptr_t pc;
int usermode;
int done, runs;
CTR4(KTR_SPARE2, "handle at %d: now %d.%08x%08x",
curcpu, now->sec, (unsigned int)(now->frac >> 32),
(unsigned int)(now->frac & 0xffffffff));
done = 0;
if (fake) {
frame = NULL;
usermode = 0;
pc = 0;
} else {
frame = curthread->td_intr_frame;
usermode = TRAPF_USERMODE(frame);
pc = TRAPF_PC(frame);
}
state = DPCPU_PTR(timerstate);
runs = 0;
while (bintime_cmp(now, &state->nexthard, >=)) {
bintime_add(&state->nexthard, &hardperiod);
runs++;
}
if ((timer->et_flags & ET_FLAGS_PERCPU) == 0 &&
bintime_cmp(&state->nexthard, &nexthard, >))
nexthard = state->nexthard;
if (runs && fake < 2) {
hardclock_cnt(runs, usermode);
done = 1;
}
runs = 0;
while (bintime_cmp(now, &state->nextstat, >=)) {
bintime_add(&state->nextstat, &statperiod);
runs++;
}
if (runs && fake < 2) {
statclock_cnt(runs, usermode);
done = 1;
}
if (profiling) {
runs = 0;
while (bintime_cmp(now, &state->nextprof, >=)) {
bintime_add(&state->nextprof, &profperiod);
runs++;
}
if (runs && !fake) {
profclock_cnt(runs, usermode, pc);
done = 1;
}
} else
state->nextprof = state->nextstat;
#ifdef KDTRACE_HOOKS
if (fake == 0 && cyclic_clock_func != NULL &&
state->nextcyc.sec != -1 &&
bintime_cmp(now, &state->nextcyc, >=)) {
state->nextcyc.sec = -1;
(*cyclic_clock_func)(frame);
}
#endif
getnextcpuevent(&t, 0);
if (fake == 2) {
state->nextevent = t;
return (done);
}
ET_HW_LOCK(state);
if (!busy) {
state->idle = 0;
state->nextevent = t;
loadtimer(now, 0);
}
ET_HW_UNLOCK(state);
return (done);
}
/*
* Schedule binuptime of the next event on current CPU.
*/
static void
getnextcpuevent(struct bintime *event, int idle)
{
struct bintime tmp;
struct pcpu_state *state;
int skip;
state = DPCPU_PTR(timerstate);
/* Handle hardclock() events. */
*event = state->nexthard;
if (idle || (!activetick && !profiling &&
(timer->et_flags & ET_FLAGS_PERCPU) == 0)) {
skip = idle ? 4 : (stathz / 2);
if (curcpu == CPU_FIRST() && tc_min_ticktock_freq > skip)
skip = tc_min_ticktock_freq;
skip = callout_tickstofirst(hz / skip) - 1;
CTR2(KTR_SPARE2, "skip at %d: %d", curcpu, skip);
tmp = hardperiod;
bintime_mul(&tmp, skip);
bintime_add(event, &tmp);
}
if (!idle) { /* If CPU is active - handle other types of events. */
if (bintime_cmp(event, &state->nextstat, >))
*event = state->nextstat;
if (profiling && bintime_cmp(event, &state->nextprof, >))
*event = state->nextprof;
}
#ifdef KDTRACE_HOOKS
if (state->nextcyc.sec != -1 && bintime_cmp(event, &state->nextcyc, >))
*event = state->nextcyc;
#endif
}
/*
* Schedule binuptime of the next event on all CPUs.
*/
static void
getnextevent(struct bintime *event)
{
struct pcpu_state *state;
#ifdef SMP
int cpu;
#endif
int c, nonidle;
state = DPCPU_PTR(timerstate);
*event = state->nextevent;
c = curcpu;
nonidle = !state->idle;
if ((timer->et_flags & ET_FLAGS_PERCPU) == 0) {
#ifdef SMP
CPU_FOREACH(cpu) {
if (curcpu == cpu)
continue;
state = DPCPU_ID_PTR(cpu, timerstate);
nonidle += !state->idle;
if (bintime_cmp(event, &state->nextevent, >)) {
*event = state->nextevent;
c = cpu;
}
}
#endif
if (nonidle != 0 && bintime_cmp(event, &nexthard, >))
*event = nexthard;
}
CTR5(KTR_SPARE2, "next at %d: next %d.%08x%08x by %d",
curcpu, event->sec, (unsigned int)(event->frac >> 32),
(unsigned int)(event->frac & 0xffffffff), c);
}
/* Hardware timer callback function. */
static void
timercb(struct eventtimer *et, void *arg)
{
struct bintime now;
struct bintime *next;
struct pcpu_state *state;
#ifdef SMP
int cpu, bcast;
#endif
/* Do not touch anything if somebody reconfiguring timers. */
if (busy)
return;
/* Update present and next tick times. */
state = DPCPU_PTR(timerstate);
if (et->et_flags & ET_FLAGS_PERCPU) {
next = &state->nexttick;
} else
next = &nexttick;
if (periodic) {
now = *next; /* Ex-next tick time becomes present time. */
bintime_add(next, &timerperiod); /* Next tick in 1 period. */
} else {
binuptime(&now); /* Get present time from hardware. */
next->sec = -1; /* Next tick is not scheduled yet. */
}
state->now = now;
CTR4(KTR_SPARE2, "intr at %d: now %d.%08x%08x",
curcpu, now.sec, (unsigned int)(now.frac >> 32),
(unsigned int)(now.frac & 0xffffffff));
#ifdef SMP
/* Prepare broadcasting to other CPUs for non-per-CPU timers. */
bcast = 0;
if ((et->et_flags & ET_FLAGS_PERCPU) == 0 && smp_started) {
CPU_FOREACH(cpu) {
state = DPCPU_ID_PTR(cpu, timerstate);
ET_HW_LOCK(state);
state->now = now;
if (bintime_cmp(&now, &state->nextevent, >=)) {
state->nextevent.sec++;
if (curcpu != cpu) {
state->ipi = 1;
bcast = 1;
}
}
ET_HW_UNLOCK(state);
}
}
#endif
/* Handle events for this time on this CPU. */
handleevents(&now, 0);
#ifdef SMP
/* Broadcast interrupt to other CPUs for non-per-CPU timers. */
if (bcast) {
CPU_FOREACH(cpu) {
if (curcpu == cpu)
continue;
state = DPCPU_ID_PTR(cpu, timerstate);
if (state->ipi) {
state->ipi = 0;
ipi_cpu(cpu, IPI_HARDCLOCK);
}
}
}
#endif
}
/*
* Load new value into hardware timer.
*/
static void
loadtimer(struct bintime *now, int start)
{
struct pcpu_state *state;
struct bintime new;
struct bintime *next;
uint64_t tmp;
int eq;
if (timer->et_flags & ET_FLAGS_PERCPU) {
state = DPCPU_PTR(timerstate);
next = &state->nexttick;
} else
next = &nexttick;
if (periodic) {
if (start) {
/*
* Try to start all periodic timers aligned
* to period to make events synchronous.
*/
tmp = ((uint64_t)now->sec << 36) + (now->frac >> 28);
tmp = (tmp % (timerperiod.frac >> 28)) << 28;
new.sec = 0;
new.frac = timerperiod.frac - tmp;
if (new.frac < tmp) /* Left less then passed. */
bintime_add(&new, &timerperiod);
CTR5(KTR_SPARE2, "load p at %d: now %d.%08x first in %d.%08x",
curcpu, now->sec, (unsigned int)(now->frac >> 32),
new.sec, (unsigned int)(new.frac >> 32));
*next = new;
bintime_add(next, now);
et_start(timer, &new, &timerperiod);
}
} else {
getnextevent(&new);
eq = bintime_cmp(&new, next, ==);
CTR5(KTR_SPARE2, "load at %d: next %d.%08x%08x eq %d",
curcpu, new.sec, (unsigned int)(new.frac >> 32),
(unsigned int)(new.frac & 0xffffffff),
eq);
if (!eq) {
*next = new;
bintime_sub(&new, now);
et_start(timer, &new, NULL);
}
}
}
/*
* Prepare event timer parameters after configuration changes.
*/
static void
setuptimer(void)
{
int freq;
if (periodic && (timer->et_flags & ET_FLAGS_PERIODIC) == 0)
periodic = 0;
else if (!periodic && (timer->et_flags & ET_FLAGS_ONESHOT) == 0)
periodic = 1;
singlemul = MIN(MAX(singlemul, 1), 20);
freq = hz * singlemul;
while (freq < (profiling ? profhz : stathz))
freq += hz;
freq = round_freq(timer, freq);
FREQ2BT(freq, &timerperiod);
}
/*
* Reconfigure specified per-CPU timer on other CPU. Called from IPI handler.
*/
static int
doconfigtimer(void)
{
struct bintime now;
struct pcpu_state *state;
state = DPCPU_PTR(timerstate);
switch (atomic_load_acq_int(&state->action)) {
case 1:
binuptime(&now);
ET_HW_LOCK(state);
loadtimer(&now, 1);
ET_HW_UNLOCK(state);
state->handle = 0;
atomic_store_rel_int(&state->action, 0);
return (1);
case 2:
ET_HW_LOCK(state);
et_stop(timer);
ET_HW_UNLOCK(state);
state->handle = 0;
atomic_store_rel_int(&state->action, 0);
return (1);
}
if (atomic_readandclear_int(&state->handle) && !busy) {
binuptime(&now);
handleevents(&now, 0);
return (1);
}
return (0);
}
/*
* Reconfigure specified timer.
* For per-CPU timers use IPI to make other CPUs to reconfigure.
*/
static void
configtimer(int start)
{
struct bintime now, next;
struct pcpu_state *state;
int cpu;
if (start) {
setuptimer();
binuptime(&now);
}
critical_enter();
ET_HW_LOCK(DPCPU_PTR(timerstate));
if (start) {
/* Initialize time machine parameters. */
next = now;
bintime_add(&next, &timerperiod);
if (periodic)
nexttick = next;
else
nexttick.sec = -1;
CPU_FOREACH(cpu) {
state = DPCPU_ID_PTR(cpu, timerstate);
state->now = now;
state->nextevent = next;
if (periodic)
state->nexttick = next;
else
state->nexttick.sec = -1;
state->nexthard = next;
state->nextstat = next;
state->nextprof = next;
hardclock_sync(cpu);
}
busy = 0;
/* Start global timer or per-CPU timer of this CPU. */
loadtimer(&now, 1);
} else {
busy = 1;
/* Stop global timer or per-CPU timer of this CPU. */
et_stop(timer);
}
ET_HW_UNLOCK(DPCPU_PTR(timerstate));
#ifdef SMP
/* If timer is global or there is no other CPUs yet - we are done. */
if ((timer->et_flags & ET_FLAGS_PERCPU) == 0 || !smp_started) {
critical_exit();
return;
}
/* Set reconfigure flags for other CPUs. */
CPU_FOREACH(cpu) {
state = DPCPU_ID_PTR(cpu, timerstate);
atomic_store_rel_int(&state->action,
(cpu == curcpu) ? 0 : ( start ? 1 : 2));
}
/* Broadcast reconfigure IPI. */
ipi_all_but_self(IPI_HARDCLOCK);
/* Wait for reconfiguration completed. */
restart:
cpu_spinwait();
CPU_FOREACH(cpu) {
if (cpu == curcpu)
continue;
state = DPCPU_ID_PTR(cpu, timerstate);
if (atomic_load_acq_int(&state->action))
goto restart;
}
#endif
critical_exit();
}
/*
* Calculate nearest frequency supported by hardware timer.
*/
static int
round_freq(struct eventtimer *et, int freq)
{
uint64_t div;
if (et->et_frequency != 0) {
div = lmax((et->et_frequency + freq / 2) / freq, 1);
if (et->et_flags & ET_FLAGS_POW2DIV)
div = 1 << (flsl(div + div / 2) - 1);
freq = (et->et_frequency + div / 2) / div;
}
if (et->et_min_period.sec > 0)
freq = 0;
else if (et->et_min_period.frac != 0)
freq = min(freq, BT2FREQ(&et->et_min_period));
if (et->et_max_period.sec == 0 && et->et_max_period.frac != 0)
freq = max(freq, BT2FREQ(&et->et_max_period));
return (freq);
}
/*
* Configure and start event timers (BSP part).
*/
void
cpu_initclocks_bsp(void)
{
struct pcpu_state *state;
int base, div, cpu;
mtx_init(&et_hw_mtx, "et_hw_mtx", NULL, MTX_SPIN);
CPU_FOREACH(cpu) {
state = DPCPU_ID_PTR(cpu, timerstate);
mtx_init(&state->et_hw_mtx, "et_hw_mtx", NULL, MTX_SPIN);
#ifdef KDTRACE_HOOKS
state->nextcyc.sec = -1;
#endif
}
#ifdef SMP
callout_new_inserted = cpu_new_callout;
#endif
periodic = want_periodic;
/* Grab requested timer or the best of present. */
if (timername[0])
timer = et_find(timername, 0, 0);
if (timer == NULL && periodic) {
timer = et_find(NULL,
ET_FLAGS_PERIODIC, ET_FLAGS_PERIODIC);
}
if (timer == NULL) {
timer = et_find(NULL,
ET_FLAGS_ONESHOT, ET_FLAGS_ONESHOT);
}
if (timer == NULL && !periodic) {
timer = et_find(NULL,
ET_FLAGS_PERIODIC, ET_FLAGS_PERIODIC);
}
if (timer == NULL)
panic("No usable event timer found!");
et_init(timer, timercb, NULL, NULL);
/* Adapt to timer capabilities. */
if (periodic && (timer->et_flags & ET_FLAGS_PERIODIC) == 0)
periodic = 0;
else if (!periodic && (timer->et_flags & ET_FLAGS_ONESHOT) == 0)
periodic = 1;
if (timer->et_flags & ET_FLAGS_C3STOP)
cpu_disable_deep_sleep++;
/*
* We honor the requested 'hz' value.
* We want to run stathz in the neighborhood of 128hz.
* We would like profhz to run as often as possible.
*/
if (singlemul <= 0 || singlemul > 20) {
if (hz >= 1500 || (hz % 128) == 0)
singlemul = 1;
else if (hz >= 750)
singlemul = 2;
else
singlemul = 4;
}
if (periodic) {
base = round_freq(timer, hz * singlemul);
singlemul = max((base + hz / 2) / hz, 1);
hz = (base + singlemul / 2) / singlemul;
if (base <= 128)
stathz = base;
else {
div = base / 128;
if (div >= singlemul && (div % singlemul) == 0)
div++;
stathz = base / div;
}
profhz = stathz;
while ((profhz + stathz) <= 128 * 64)
profhz += stathz;
profhz = round_freq(timer, profhz);
} else {
hz = round_freq(timer, hz);
stathz = round_freq(timer, 127);
profhz = round_freq(timer, stathz * 64);
}
tick = 1000000 / hz;
FREQ2BT(hz, &hardperiod);
FREQ2BT(stathz, &statperiod);
FREQ2BT(profhz, &profperiod);
ET_LOCK();
configtimer(1);
ET_UNLOCK();
}
/*
* Start per-CPU event timers on APs.
*/
void
cpu_initclocks_ap(void)
{
struct bintime now;
struct pcpu_state *state;
state = DPCPU_PTR(timerstate);
binuptime(&now);
ET_HW_LOCK(state);
if ((timer->et_flags & ET_FLAGS_PERCPU) == 0 && periodic) {
state->now = nexttick;
bintime_sub(&state->now, &timerperiod);
} else
state->now = now;
hardclock_sync(curcpu);
handleevents(&state->now, 2);
if (timer->et_flags & ET_FLAGS_PERCPU)
loadtimer(&now, 1);
ET_HW_UNLOCK(state);
}
/*
* Switch to profiling clock rates.
*/
void
cpu_startprofclock(void)
{
ET_LOCK();
if (periodic) {
configtimer(0);
profiling = 1;
configtimer(1);
} else
profiling = 1;
ET_UNLOCK();
}
/*
* Switch to regular clock rates.
*/
void
cpu_stopprofclock(void)
{
ET_LOCK();
if (periodic) {
configtimer(0);
profiling = 0;
configtimer(1);
} else
profiling = 0;
ET_UNLOCK();
}
/*
* Switch to idle mode (all ticks handled).
*/
void
cpu_idleclock(void)
{
struct bintime now, t;
struct pcpu_state *state;
if (idletick || busy ||
(periodic && (timer->et_flags & ET_FLAGS_PERCPU))
#ifdef DEVICE_POLLING
|| curcpu == CPU_FIRST()
#endif
)
return;
state = DPCPU_PTR(timerstate);
if (periodic)
now = state->now;
else
binuptime(&now);
CTR4(KTR_SPARE2, "idle at %d: now %d.%08x%08x",
curcpu, now.sec, (unsigned int)(now.frac >> 32),
(unsigned int)(now.frac & 0xffffffff));
getnextcpuevent(&t, 1);
ET_HW_LOCK(state);
state->idle = 1;
state->nextevent = t;
if (!periodic)
loadtimer(&now, 0);
ET_HW_UNLOCK(state);
}
/*
* Switch to active mode (skip empty ticks).
*/
void
cpu_activeclock(void)
{
struct bintime now;
struct pcpu_state *state;
struct thread *td;
state = DPCPU_PTR(timerstate);
if (state->idle == 0 || busy)
return;
if (periodic)
now = state->now;
else
binuptime(&now);
CTR4(KTR_SPARE2, "active at %d: now %d.%08x%08x",
curcpu, now.sec, (unsigned int)(now.frac >> 32),
(unsigned int)(now.frac & 0xffffffff));
spinlock_enter();
td = curthread;
td->td_intr_nesting_level++;
handleevents(&now, 1);
td->td_intr_nesting_level--;
spinlock_exit();
}
#ifdef KDTRACE_HOOKS
void
clocksource_cyc_set(const struct bintime *t)
{
struct bintime now;
struct pcpu_state *state;
state = DPCPU_PTR(timerstate);
if (periodic)
now = state->now;
else
binuptime(&now);
CTR4(KTR_SPARE2, "set_cyc at %d: now %d.%08x%08x",
curcpu, now.sec, (unsigned int)(now.frac >> 32),
(unsigned int)(now.frac & 0xffffffff));
CTR4(KTR_SPARE2, "set_cyc at %d: t %d.%08x%08x",
curcpu, t->sec, (unsigned int)(t->frac >> 32),
(unsigned int)(t->frac & 0xffffffff));
ET_HW_LOCK(state);
if (bintime_cmp(t, &state->nextcyc, ==)) {
ET_HW_UNLOCK(state);
return;
}
state->nextcyc = *t;
if (bintime_cmp(&state->nextcyc, &state->nextevent, >=)) {
ET_HW_UNLOCK(state);
return;
}
state->nextevent = state->nextcyc;
if (!periodic)
loadtimer(&now, 0);
ET_HW_UNLOCK(state);
}
#endif
#ifdef SMP
static void
cpu_new_callout(int cpu, int ticks)
{
struct bintime tmp;
struct pcpu_state *state;
CTR3(KTR_SPARE2, "new co at %d: on %d in %d",
curcpu, cpu, ticks);
state = DPCPU_ID_PTR(cpu, timerstate);
ET_HW_LOCK(state);
if (state->idle == 0 || busy) {
ET_HW_UNLOCK(state);
return;
}
/*
* If timer is periodic - just update next event time for target CPU.
* If timer is global - there is chance it is already programmed.
*/
if (periodic || (timer->et_flags & ET_FLAGS_PERCPU) == 0) {
tmp = hardperiod;
bintime_mul(&tmp, ticks - 1);
bintime_add(&tmp, &state->nexthard);
if (bintime_cmp(&tmp, &state->nextevent, <))
state->nextevent = tmp;
if (periodic ||
bintime_cmp(&state->nextevent, &nexttick, >=)) {
ET_HW_UNLOCK(state);
return;
}
}
/*
* Otherwise we have to wake that CPU up, as we can't get present
* bintime to reprogram global timer from here. If timer is per-CPU,
* we by definition can't do it from here.
*/
ET_HW_UNLOCK(state);
if (timer->et_flags & ET_FLAGS_PERCPU) {
state->handle = 1;
ipi_cpu(cpu, IPI_HARDCLOCK);
} else {
if (!cpu_idle_wakeup(cpu))
ipi_cpu(cpu, IPI_AST);
}
}
#endif
/*
* Report or change the active event timers hardware.
*/
static int
sysctl_kern_eventtimer_timer(SYSCTL_HANDLER_ARGS)
{
char buf[32];
struct eventtimer *et;
int error;
ET_LOCK();
et = timer;
snprintf(buf, sizeof(buf), "%s", et->et_name);
ET_UNLOCK();
error = sysctl_handle_string(oidp, buf, sizeof(buf), req);
ET_LOCK();
et = timer;
if (error != 0 || req->newptr == NULL ||
strcasecmp(buf, et->et_name) == 0) {
ET_UNLOCK();
return (error);
}
et = et_find(buf, 0, 0);
if (et == NULL) {
ET_UNLOCK();
return (ENOENT);
}
configtimer(0);
et_free(timer);
if (et->et_flags & ET_FLAGS_C3STOP)
cpu_disable_deep_sleep++;
if (timer->et_flags & ET_FLAGS_C3STOP)
cpu_disable_deep_sleep--;
periodic = want_periodic;
timer = et;
et_init(timer, timercb, NULL, NULL);
configtimer(1);
ET_UNLOCK();
return (error);
}
SYSCTL_PROC(_kern_eventtimer, OID_AUTO, timer,
CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_MPSAFE,
0, 0, sysctl_kern_eventtimer_timer, "A", "Chosen event timer");
/*
* Report or change the active event timer periodicity.
*/
static int
sysctl_kern_eventtimer_periodic(SYSCTL_HANDLER_ARGS)
{
int error, val;
val = periodic;
error = sysctl_handle_int(oidp, &val, 0, req);
if (error != 0 || req->newptr == NULL)
return (error);
ET_LOCK();
configtimer(0);
periodic = want_periodic = val;
configtimer(1);
ET_UNLOCK();
return (error);
}
SYSCTL_PROC(_kern_eventtimer, OID_AUTO, periodic,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
0, 0, sysctl_kern_eventtimer_periodic, "I", "Enable event timer periodic mode");