/*
* Read the current hypervisor system uptime value from Xen.
*/
void
xen_fetch_uptime(struct timespec *ts)
{
shared_info_t *s = HYPERVISOR_shared_info;
struct vcpu_time_info *src;
struct shadow_time_info dst;
uint32_t pre_version, post_version;
src = &s->vcpu_info[smp_processor_id()].time;
spinlock_enter();
do {
pre_version = dst.version = src->version;
rmb();
dst.system_timestamp = src->system_time;
rmb();
post_version = src->version;
}
while ((pre_version & 1) | (pre_version ^ post_version));
spinlock_exit();
ts->tv_sec = dst.system_timestamp / 1000000000;
ts->tv_nsec = dst.system_timestamp % 1000000000;
}
void
_thread_lock(struct thread *td)
#endif
{
struct mtx *m;
uintptr_t tid, v;
tid = (uintptr_t)curthread;
spinlock_enter();
m = td->td_lock;
thread_lock_validate(m, 0, file, line);
v = MTX_READ_VALUE(m);
if (__predict_true(v == MTX_UNOWNED)) {
if (__predict_false(!_mtx_obtain_lock(m, tid)))
goto slowpath_unlocked;
} else if (v == tid) {
m->mtx_recurse++;
} else
goto slowpath_unlocked;
if (__predict_true(m == td->td_lock)) {
WITNESS_LOCK(&m->lock_object, LOP_EXCLUSIVE, file, line);
return;
}
if (m->mtx_recurse != 0)
m->mtx_recurse--;
else
_mtx_release_lock_quick(m);
slowpath_unlocked:
spinlock_exit();
thread_lock_flags_(td, 0, 0, 0);
}
static void
atpic_disable_source(struct intsrc *isrc, int eoi)
{
struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc;
struct atpic *ap = (struct atpic *)isrc->is_pic;
spinlock_enter();
if (ai->at_trigger != INTR_TRIGGER_EDGE) {
*ap->at_imen |= IMEN_MASK(ai);
outb(ap->at_ioaddr + ICU_IMR_OFFSET, *ap->at_imen);
}
/*
* Take care to call these functions directly instead of through
* a function pointer. All of the referenced variables should
* still be hot in the cache.
*/
if (eoi == PIC_EOI) {
if (isrc->is_pic == &atpics[MASTER].at_pic)
_atpic_eoi_master(isrc);
else
_atpic_eoi_slave(isrc);
}
spinlock_exit();
}
static void
atpic_eoi_slave(struct intsrc *isrc)
{
#ifndef AUTO_EOI_2
spinlock_enter();
_atpic_eoi_slave(isrc);
spinlock_exit();
#endif
}
static int
atpic_config_intr(struct intsrc *isrc, enum intr_trigger trig,
enum intr_polarity pol)
{
struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc;
u_int vector;
/* Map conforming values to edge/hi and sanity check the values. */
if (trig == INTR_TRIGGER_CONFORM)
trig = INTR_TRIGGER_EDGE;
if (pol == INTR_POLARITY_CONFORM)
pol = INTR_POLARITY_HIGH;
vector = atpic_vector(isrc);
if ((trig == INTR_TRIGGER_EDGE && pol == INTR_POLARITY_LOW) ||
(trig == INTR_TRIGGER_LEVEL && pol == INTR_POLARITY_HIGH)) {
printf(
"atpic: Mismatched config for IRQ%u: trigger %s, polarity %s\n",
vector, trig == INTR_TRIGGER_EDGE ? "edge" : "level",
pol == INTR_POLARITY_HIGH ? "high" : "low");
return (EINVAL);
}
/* If there is no change, just return. */
if (ai->at_trigger == trig)
return (0);
/*
* Certain IRQs can never be level/lo, so don't try to set them
* that way if asked. At least some ELCR registers ignore setting
* these bits as well.
*/
if ((vector == 0 || vector == 1 || vector == 2 || vector == 13) &&
trig == INTR_TRIGGER_LEVEL) {
if (bootverbose)
printf(
"atpic: Ignoring invalid level/low configuration for IRQ%u\n",
vector);
return (EINVAL);
}
if (!elcr_found) {
if (bootverbose)
printf("atpic: No ELCR to configure IRQ%u as %s\n",
vector, trig == INTR_TRIGGER_EDGE ? "edge/high" :
"level/low");
return (ENXIO);
}
if (bootverbose)
printf("atpic: Programming IRQ%u as %s\n", vector,
trig == INTR_TRIGGER_EDGE ? "edge/high" : "level/low");
spinlock_enter();
elcr_write_trigger(atpic_vector(isrc), trig);
ai->at_trigger = trig;
spinlock_exit();
return (0);
}
static void
atpic_enable_source(struct intsrc *isrc)
{
struct atpic_intsrc *ai = (struct atpic_intsrc *)isrc;
struct atpic *ap = (struct atpic *)isrc->is_pic;
spinlock_enter();
if (*ap->at_imen & IMEN_MASK(ai)) {
*ap->at_imen &= ~IMEN_MASK(ai);
outb(ap->at_ioaddr + ICU_IMR_OFFSET, *ap->at_imen);
}
spinlock_exit();
}
void
cpu_idle(int busy)
{
spinlock_enter();
if (!busy)
cpu_idleclock();
if (!sched_runnable())
__asm __volatile(
"dsb sy \n"
"wfi \n");
if (!busy)
cpu_activeclock();
spinlock_exit();
}
static void
i8259_init(struct atpic *pic, int slave)
{
int imr_addr;
/* Reset the PIC and program with next four bytes. */
spinlock_enter();
#ifdef DEV_MCA
/* MCA uses level triggered interrupts. */
if (MCA_system)
outb(pic->at_ioaddr, ICW1_RESET | ICW1_IC4 | ICW1_LTIM);
else
#endif
outb(pic->at_ioaddr, ICW1_RESET | ICW1_IC4);
imr_addr = pic->at_ioaddr + ICU_IMR_OFFSET;
/* Start vector. */
outb(imr_addr, pic->at_intbase);
/*
* Setup slave links. For the master pic, indicate what line
* the slave is configured on. For the slave indicate
* which line on the master we are connected to.
*/
if (slave)
outb(imr_addr, ICU_SLAVEID);
else
outb(imr_addr, IRQ_MASK(ICU_SLAVEID));
/* Set mode. */
if (slave)
outb(imr_addr, SLAVE_MODE);
else
outb(imr_addr, MASTER_MODE);
/* Set interrupt enable mask. */
outb(imr_addr, *pic->at_imen);
/* Reset is finished, default to IRR on read. */
outb(pic->at_ioaddr, OCW3_SEL | OCW3_RR);
#ifndef PC98
/* OCW2_L1 sets priority order to 3-7, 0-2 (com2 first). */
if (!slave)
outb(pic->at_ioaddr, OCW2_R | OCW2_SL | OCW2_L1);
#endif
spinlock_exit();
}
void
smp_rendezvous(void (*setup_func)(void *),
void (*action_func)(void *),
void (*teardown_func)(void *),
void *arg)
{
/* Look comments in the smp_rendezvous_cpus() case. */
spinlock_enter();
if (setup_func != NULL)
setup_func(arg);
if (action_func != NULL)
action_func(arg);
if (teardown_func != NULL)
teardown_func(arg);
spinlock_exit();
}
void
smp_rendezvous_cpus(cpuset_t map,
void (*setup_func)(void *),
void (*action_func)(void *),
void (*teardown_func)(void *),
void *arg)
{
/*
* In the !SMP case we just need to ensure the same initial conditions
* as the SMP case.
*/
spinlock_enter();
if (setup_func != NULL)
setup_func(arg);
if (action_func != NULL)
action_func(arg);
if (teardown_func != NULL)
teardown_func(arg);
spinlock_exit();
}
/*
* _mtx_lock_spin: the tougher part of acquiring an MTX_SPIN lock.
*
* This is only called if we need to actually spin for the lock. Recursion
* is handled inline.
*/
void
_mtx_lock_spin(struct mtx *m, uintptr_t tid, int opts, const char *file,
int line)
{
int i = 0;
#ifdef LOCK_PROFILING
int contested = 0;
uint64_t waittime = 0;
#endif
if (LOCK_LOG_TEST(&m->lock_object, opts))
CTR1(KTR_LOCK, "_mtx_lock_spin: %p spinning", m);
lock_profile_obtain_lock_failed(&m->lock_object, &contested, &waittime);
while (!_obtain_lock(m, tid)) {
/* Give interrupts a chance while we spin. */
spinlock_exit();
while (m->mtx_lock != MTX_UNOWNED) {
if (i++ < 10000000) {
cpu_spinwait();
continue;
}
if (i < 60000000 || kdb_active || panicstr != NULL)
DELAY(1);
else
_mtx_lock_spin_failed(m);
cpu_spinwait();
}
spinlock_enter();
}
if (LOCK_LOG_TEST(&m->lock_object, opts))
CTR1(KTR_LOCK, "_mtx_lock_spin: %p spin done", m);
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(LS_MTX_SPIN_LOCK_ACQUIRE, m,
contested, waittime, (file), (line));
LOCKSTAT_RECORD1(LS_MTX_SPIN_LOCK_SPIN, m, i);
}
void
smp_rendezvous_cpus(cpuset_t map,
void (* setup_func)(void *),
void (* action_func)(void *),
void (* teardown_func)(void *),
void *arg)
{
int curcpumap, i, ncpus = 0;
/* Look comments in the !SMP case. */
if (!smp_started) {
spinlock_enter();
if (setup_func != NULL)
setup_func(arg);
if (action_func != NULL)
action_func(arg);
if (teardown_func != NULL)
teardown_func(arg);
spinlock_exit();
return;
}
CPU_FOREACH(i) {
if (CPU_ISSET(i, &map))
ncpus++;
}
if (ncpus == 0)
panic("ncpus is 0 with non-zero map");
mtx_lock_spin(&smp_ipi_mtx);
/* Pass rendezvous parameters via global variables. */
smp_rv_ncpus = ncpus;
smp_rv_setup_func = setup_func;
smp_rv_action_func = action_func;
smp_rv_teardown_func = teardown_func;
smp_rv_func_arg = arg;
smp_rv_waiters[1] = 0;
smp_rv_waiters[2] = 0;
smp_rv_waiters[3] = 0;
atomic_store_rel_int(&smp_rv_waiters[0], 0);
/*
* Signal other processors, which will enter the IPI with
* interrupts off.
*/
curcpumap = CPU_ISSET(curcpu, &map);
CPU_CLR(curcpu, &map);
ipi_selected(map, IPI_RENDEZVOUS);
/* Check if the current CPU is in the map */
if (curcpumap != 0)
smp_rendezvous_action();
/*
* Ensure that the master CPU waits for all the other
* CPUs to finish the rendezvous, so that smp_rv_*
* pseudo-structure and the arg are guaranteed to not
* be in use.
*/
while (atomic_load_acq_int(&smp_rv_waiters[3]) < ncpus)
cpu_spinwait();
mtx_unlock_spin(&smp_ipi_mtx);
}
void
thread_lock_flags_(struct thread *td, int opts, const char *file, int line)
{
struct mtx *m;
uintptr_t tid, v;
struct lock_delay_arg lda;
#ifdef LOCK_PROFILING
int contested = 0;
uint64_t waittime = 0;
#endif
#ifdef KDTRACE_HOOKS
int64_t spin_time = 0;
#endif
#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
int doing_lockprof = 1;
#endif
tid = (uintptr_t)curthread;
if (SCHEDULER_STOPPED()) {
/*
* Ensure that spinlock sections are balanced even when the
* scheduler is stopped, since we may otherwise inadvertently
* re-enable interrupts while dumping core.
*/
spinlock_enter();
return;
}
lock_delay_arg_init(&lda, &mtx_spin_delay);
#ifdef LOCK_PROFILING
doing_lockprof = 1;
#elif defined(KDTRACE_HOOKS)
doing_lockprof = lockstat_enabled;
if (__predict_false(doing_lockprof))
spin_time -= lockstat_nsecs(&td->td_lock->lock_object);
#endif
for (;;) {
retry:
v = MTX_UNOWNED;
spinlock_enter();
m = td->td_lock;
thread_lock_validate(m, opts, file, line);
for (;;) {
if (_mtx_obtain_lock_fetch(m, &v, tid))
break;
if (v == MTX_UNOWNED)
continue;
if (v == tid) {
m->mtx_recurse++;
break;
}
#ifdef HWPMC_HOOKS
PMC_SOFT_CALL( , , lock, failed);
#endif
lock_profile_obtain_lock_failed(&m->lock_object,
&contested, &waittime);
/* Give interrupts a chance while we spin. */
spinlock_exit();
do {
if (lda.spin_cnt < 10000000) {
lock_delay(&lda);
} else {
lda.spin_cnt++;
if (lda.spin_cnt < 60000000 ||
kdb_active || panicstr != NULL)
DELAY(1);
else
_mtx_lock_spin_failed(m);
cpu_spinwait();
}
if (m != td->td_lock)
goto retry;
v = MTX_READ_VALUE(m);
} while (v != MTX_UNOWNED);
spinlock_enter();
}
if (m == td->td_lock)
break;
__mtx_unlock_spin(m); /* does spinlock_exit() */
}
LOCK_LOG_LOCK("LOCK", &m->lock_object, opts, m->mtx_recurse, file,
line);
WITNESS_LOCK(&m->lock_object, opts | LOP_EXCLUSIVE, file, line);
#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
if (__predict_true(!doing_lockprof))
return;
#endif
#ifdef KDTRACE_HOOKS
spin_time += lockstat_nsecs(&m->lock_object);
#endif
if (m->mtx_recurse == 0)
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(spin__acquire, m,
contested, waittime, file, line);
#ifdef KDTRACE_HOOKS
if (lda.spin_cnt != 0)
LOCKSTAT_RECORD1(thread__spin, m, spin_time);
#endif
}
/*
* _mtx_lock_spin_cookie: the tougher part of acquiring an MTX_SPIN lock.
*
* This is only called if we need to actually spin for the lock. Recursion
* is handled inline.
*/
void
_mtx_lock_spin_cookie(volatile uintptr_t *c, uintptr_t tid, int opts,
const char *file, int line)
{
struct mtx *m;
struct lock_delay_arg lda;
#ifdef LOCK_PROFILING
int contested = 0;
uint64_t waittime = 0;
#endif
#ifdef KDTRACE_HOOKS
int64_t spin_time = 0;
#endif
if (SCHEDULER_STOPPED())
return;
lock_delay_arg_init(&lda, &mtx_spin_delay);
m = mtxlock2mtx(c);
if (LOCK_LOG_TEST(&m->lock_object, opts))
CTR1(KTR_LOCK, "_mtx_lock_spin: %p spinning", m);
KTR_STATE1(KTR_SCHED, "thread", sched_tdname((struct thread *)tid),
"spinning", "lockname:\"%s\"", m->lock_object.lo_name);
#ifdef HWPMC_HOOKS
PMC_SOFT_CALL( , , lock, failed);
#endif
lock_profile_obtain_lock_failed(&m->lock_object, &contested, &waittime);
#ifdef KDTRACE_HOOKS
spin_time -= lockstat_nsecs(&m->lock_object);
#endif
for (;;) {
if (m->mtx_lock == MTX_UNOWNED && _mtx_obtain_lock(m, tid))
break;
/* Give interrupts a chance while we spin. */
spinlock_exit();
while (m->mtx_lock != MTX_UNOWNED) {
if (lda.spin_cnt < 10000000) {
lock_delay(&lda);
continue;
}
lda.spin_cnt++;
if (lda.spin_cnt < 60000000 || kdb_active ||
panicstr != NULL)
DELAY(1);
else
_mtx_lock_spin_failed(m);
cpu_spinwait();
}
spinlock_enter();
}
#ifdef KDTRACE_HOOKS
spin_time += lockstat_nsecs(&m->lock_object);
#endif
if (LOCK_LOG_TEST(&m->lock_object, opts))
CTR1(KTR_LOCK, "_mtx_lock_spin: %p spin done", m);
KTR_STATE0(KTR_SCHED, "thread", sched_tdname((struct thread *)tid),
"running");
#ifdef KDTRACE_HOOKS
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(spin__acquire, m,
contested, waittime, file, line);
if (spin_time != 0)
LOCKSTAT_RECORD1(spin__spin, m, spin_time);
#endif
}
void
_mtx_lock_spin_cookie(volatile uintptr_t *c, uintptr_t v)
#endif
{
struct mtx *m;
struct lock_delay_arg lda;
uintptr_t tid;
#ifdef LOCK_PROFILING
int contested = 0;
uint64_t waittime = 0;
#endif
#ifdef KDTRACE_HOOKS
int64_t spin_time = 0;
#endif
#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
int doing_lockprof;
#endif
tid = (uintptr_t)curthread;
m = mtxlock2mtx(c);
if (__predict_false(v == MTX_UNOWNED))
v = MTX_READ_VALUE(m);
if (__predict_false(v == tid)) {
m->mtx_recurse++;
return;
}
if (SCHEDULER_STOPPED())
return;
lock_delay_arg_init(&lda, &mtx_spin_delay);
if (LOCK_LOG_TEST(&m->lock_object, opts))
CTR1(KTR_LOCK, "_mtx_lock_spin: %p spinning", m);
KTR_STATE1(KTR_SCHED, "thread", sched_tdname((struct thread *)tid),
"spinning", "lockname:\"%s\"", m->lock_object.lo_name);
#ifdef HWPMC_HOOKS
PMC_SOFT_CALL( , , lock, failed);
#endif
lock_profile_obtain_lock_failed(&m->lock_object, &contested, &waittime);
#ifdef LOCK_PROFILING
doing_lockprof = 1;
#elif defined(KDTRACE_HOOKS)
doing_lockprof = lockstat_enabled;
if (__predict_false(doing_lockprof))
spin_time -= lockstat_nsecs(&m->lock_object);
#endif
for (;;) {
if (v == MTX_UNOWNED) {
if (_mtx_obtain_lock_fetch(m, &v, tid))
break;
continue;
}
/* Give interrupts a chance while we spin. */
spinlock_exit();
do {
if (lda.spin_cnt < 10000000) {
lock_delay(&lda);
} else {
lda.spin_cnt++;
if (lda.spin_cnt < 60000000 || kdb_active ||
panicstr != NULL)
DELAY(1);
else
_mtx_lock_spin_failed(m);
cpu_spinwait();
}
v = MTX_READ_VALUE(m);
} while (v != MTX_UNOWNED);
spinlock_enter();
}
if (LOCK_LOG_TEST(&m->lock_object, opts))
CTR1(KTR_LOCK, "_mtx_lock_spin: %p spin done", m);
KTR_STATE0(KTR_SCHED, "thread", sched_tdname((struct thread *)tid),
"running");
#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
if (__predict_true(!doing_lockprof))
return;
#endif
#ifdef KDTRACE_HOOKS
spin_time += lockstat_nsecs(&m->lock_object);
#endif
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(spin__acquire, m,
contested, waittime, file, line);
#ifdef KDTRACE_HOOKS
if (lda.spin_cnt != 0)
LOCKSTAT_RECORD1(spin__spin, m, spin_time);
#endif
}
void
_thread_lock_flags(struct thread *td, int opts, const char *file, int line)
{
struct mtx *m;
uintptr_t tid;
int i;
#ifdef LOCK_PROFILING
int contested = 0;
uint64_t waittime = 0;
#endif
#ifdef KDTRACE_HOOKS
uint64_t spin_cnt = 0;
#endif
i = 0;
tid = (uintptr_t)curthread;
for (;;) {
retry:
spinlock_enter();
m = td->td_lock;
KASSERT(m->mtx_lock != MTX_DESTROYED,
("thread_lock() of destroyed mutex @ %s:%d", file, line));
KASSERT(LOCK_CLASS(&m->lock_object) == &lock_class_mtx_spin,
("thread_lock() of sleep mutex %s @ %s:%d",
m->lock_object.lo_name, file, line));
if (mtx_owned(m))
KASSERT((m->lock_object.lo_flags & LO_RECURSABLE) != 0,
("thread_lock: recursed on non-recursive mutex %s @ %s:%d\n",
m->lock_object.lo_name, file, line));
WITNESS_CHECKORDER(&m->lock_object,
opts | LOP_NEWORDER | LOP_EXCLUSIVE, file, line, NULL);
while (!_obtain_lock(m, tid)) {
#ifdef KDTRACE_HOOKS
spin_cnt++;
#endif
if (m->mtx_lock == tid) {
m->mtx_recurse++;
break;
}
lock_profile_obtain_lock_failed(&m->lock_object,
&contested, &waittime);
/* Give interrupts a chance while we spin. */
spinlock_exit();
while (m->mtx_lock != MTX_UNOWNED) {
if (i++ < 10000000)
cpu_spinwait();
else if (i < 60000000 ||
kdb_active || panicstr != NULL)
DELAY(1);
else
_mtx_lock_spin_failed(m);
cpu_spinwait();
if (m != td->td_lock)
goto retry;
}
spinlock_enter();
}
if (m == td->td_lock)
break;
_rel_spin_lock(m); /* does spinlock_exit() */
#ifdef KDTRACE_HOOKS
spin_cnt++;
#endif
}
if (m->mtx_recurse == 0)
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(LS_MTX_SPIN_LOCK_ACQUIRE,
m, contested, waittime, (file), (line));
LOCK_LOG_LOCK("LOCK", &m->lock_object, opts, m->mtx_recurse, file,
line);
WITNESS_LOCK(&m->lock_object, opts | LOP_EXCLUSIVE, file, line);
LOCKSTAT_RECORD1(LS_THREAD_LOCK_SPIN, m, spin_cnt);
}
void
thread_lock_flags_(struct thread *td, int opts, const char *file, int line)
{
struct mtx *m;
uintptr_t tid;
struct lock_delay_arg lda;
#ifdef LOCK_PROFILING
int contested = 0;
uint64_t waittime = 0;
#endif
#ifdef KDTRACE_HOOKS
int64_t spin_time = 0;
#endif
tid = (uintptr_t)curthread;
if (SCHEDULER_STOPPED()) {
/*
* Ensure that spinlock sections are balanced even when the
* scheduler is stopped, since we may otherwise inadvertently
* re-enable interrupts while dumping core.
*/
spinlock_enter();
return;
}
lock_delay_arg_init(&lda, &mtx_spin_delay);
#ifdef KDTRACE_HOOKS
spin_time -= lockstat_nsecs(&td->td_lock->lock_object);
#endif
for (;;) {
retry:
spinlock_enter();
m = td->td_lock;
KASSERT(m->mtx_lock != MTX_DESTROYED,
("thread_lock() of destroyed mutex @ %s:%d", file, line));
KASSERT(LOCK_CLASS(&m->lock_object) == &lock_class_mtx_spin,
("thread_lock() of sleep mutex %s @ %s:%d",
m->lock_object.lo_name, file, line));
if (mtx_owned(m))
KASSERT((m->lock_object.lo_flags & LO_RECURSABLE) != 0,
("thread_lock: recursed on non-recursive mutex %s @ %s:%d\n",
m->lock_object.lo_name, file, line));
WITNESS_CHECKORDER(&m->lock_object,
opts | LOP_NEWORDER | LOP_EXCLUSIVE, file, line, NULL);
for (;;) {
if (m->mtx_lock == MTX_UNOWNED && _mtx_obtain_lock(m, tid))
break;
if (m->mtx_lock == tid) {
m->mtx_recurse++;
break;
}
#ifdef HWPMC_HOOKS
PMC_SOFT_CALL( , , lock, failed);
#endif
lock_profile_obtain_lock_failed(&m->lock_object,
&contested, &waittime);
/* Give interrupts a chance while we spin. */
spinlock_exit();
while (m->mtx_lock != MTX_UNOWNED) {
if (lda.spin_cnt < 10000000) {
lock_delay(&lda);
} else {
lda.spin_cnt++;
if (lda.spin_cnt < 60000000 ||
kdb_active || panicstr != NULL)
DELAY(1);
else
_mtx_lock_spin_failed(m);
cpu_spinwait();
}
if (m != td->td_lock)
goto retry;
}
spinlock_enter();
}
if (m == td->td_lock)
break;
__mtx_unlock_spin(m); /* does spinlock_exit() */
}
#ifdef KDTRACE_HOOKS
spin_time += lockstat_nsecs(&m->lock_object);
#endif
if (m->mtx_recurse == 0)
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(spin__acquire, m,
contested, waittime, file, line);
LOCK_LOG_LOCK("LOCK", &m->lock_object, opts, m->mtx_recurse, file,
line);
WITNESS_LOCK(&m->lock_object, opts | LOP_EXCLUSIVE, file, line);
#ifdef KDTRACE_HOOKS
if (spin_time != 0)
LOCKSTAT_RECORD1(thread__spin, m, spin_time);
#endif
}
void
smp_init_secondary(u_int32_t cpuid)
{
if (cpuid >= MAXCPU)
panic ("cpu id exceeds MAXCPU\n");
/* tlb init */
R4K_SetWIRED(0);
R4K_TLBFlush(num_tlbentries);
R4K_SetWIRED(VMWIRED_ENTRIES);
MachSetPID(0);
Mips_SyncCache();
mips_cp0_status_write(0);
while (!aps_ready)
;
mips_sync(); mips_sync();
/* Initialize curthread. */
KASSERT(PCPU_GET(idlethread) != NULL, ("no idle thread"));
PCPU_SET(curthread, PCPU_GET(idlethread));
mtx_lock_spin(&ap_boot_mtx);
smp_cpus++;
CTR1(KTR_SMP, "SMP: AP CPU #%d Launched", PCPU_GET(cpuid));
/* Build our map of 'other' CPUs. */
PCPU_SET(other_cpus, all_cpus & ~PCPU_GET(cpumask));
printf("SMP: AP CPU #%d Launched!\n", PCPU_GET(cpuid));
if (smp_cpus == mp_ncpus) {
smp_started = 1;
smp_active = 1;
}
mtx_unlock_spin(&ap_boot_mtx);
while (smp_started == 0)
; /* nothing */
/* Enable Interrupt */
mips_cp0_status_write(SR_INT_ENAB);
/* ok, now grab sched_lock and enter the scheduler */
mtx_lock_spin(&sched_lock);
/*
* Correct spinlock nesting. The idle thread context that we are
* borrowing was created so that it would start out with a single
* spin lock (sched_lock) held in fork_trampoline(). Since we've
* explicitly acquired locks in this function, the nesting count
* is now 2 rather than 1. Since we are nested, calling
* spinlock_exit() will simply adjust the counts without allowing
* spin lock using code to interrupt us.
*/
spinlock_exit();
KASSERT(curthread->td_md.md_spinlock_count == 1, ("invalid count"));
binuptime(PCPU_PTR(switchtime));
PCPU_SET(switchticks, ticks);
/* kick off the clock on this cpu */
mips_start_timer();
cpu_throw(NULL, choosethread()); /* doesn't return */
panic("scheduler returned us to %s", __func__);
}
/*
* This function is called when a thread is about to be put on run queue
* because it has been made runnable or its priority has been adjusted. It
* determines if the new thread should be immediately preempted to. If so,
* it switches to it and eventually returns true. If not, it returns false
* so that the caller may place the thread on an appropriate run queue.
*/
int
maybe_preempt(struct thread *td)
{
#ifdef PREEMPTION
struct thread *ctd;
int cpri, pri;
/*
* The new thread should not preempt the current thread if any of the
* following conditions are true:
*
* - The kernel is in the throes of crashing (panicstr).
* - The current thread has a higher (numerically lower) or
* equivalent priority. Note that this prevents curthread from
* trying to preempt to itself.
* - It is too early in the boot for context switches (cold is set).
* - The current thread has an inhibitor set or is in the process of
* exiting. In this case, the current thread is about to switch
* out anyways, so there's no point in preempting. If we did,
* the current thread would not be properly resumed as well, so
* just avoid that whole landmine.
* - If the new thread's priority is not a realtime priority and
* the current thread's priority is not an idle priority and
* FULL_PREEMPTION is disabled.
*
* If all of these conditions are false, but the current thread is in
* a nested critical section, then we have to defer the preemption
* until we exit the critical section. Otherwise, switch immediately
* to the new thread.
*/
ctd = curthread;
THREAD_LOCK_ASSERT(td, MA_OWNED);
KASSERT((td->td_inhibitors == 0),
("maybe_preempt: trying to run inhibited thread"));
pri = td->td_priority;
cpri = ctd->td_priority;
if (panicstr != NULL || pri >= cpri || cold /* || dumping */ ||
TD_IS_INHIBITED(ctd))
return (0);
#ifndef FULL_PREEMPTION
if (pri > PRI_MAX_ITHD && cpri < PRI_MIN_IDLE)
return (0);
#endif
if (ctd->td_critnest > 1) {
CTR1(KTR_PROC, "maybe_preempt: in critical section %d",
ctd->td_critnest);
ctd->td_owepreempt = 1;
return (0);
}
/*
* Thread is runnable but not yet put on system run queue.
*/
MPASS(ctd->td_lock == td->td_lock);
MPASS(TD_ON_RUNQ(td));
TD_SET_RUNNING(td);
CTR3(KTR_PROC, "preempting to thread %p (pid %d, %s)\n", td,
td->td_proc->p_pid, td->td_name);
mi_switch(SW_INVOL | SW_PREEMPT | SWT_PREEMPT, td);
/*
* td's lock pointer may have changed. We have to return with it
* locked.
*/
spinlock_enter();
thread_unlock(ctd);
thread_lock(td);
spinlock_exit();
return (1);
#else
return (0);
#endif
}
void
thread_lock_flags_(struct thread *td, int opts, const char *file, int line)
{
struct mtx *m;
uintptr_t tid;
int i;
#ifdef LOCK_PROFILING
int contested = 0;
uint64_t waittime = 0;
#endif
#ifdef KDTRACE_HOOKS
int64_t spin_time = 0;
#endif
i = 0;
tid = (uintptr_t)curthread;
if (SCHEDULER_STOPPED())
return;
#ifdef KDTRACE_HOOKS
spin_time -= lockstat_nsecs(&td->td_lock->lock_object);
#endif
for (;;) {
retry:
spinlock_enter();
m = td->td_lock;
KASSERT(m->mtx_lock != MTX_DESTROYED,
("thread_lock() of destroyed mutex @ %s:%d", file, line));
KASSERT(LOCK_CLASS(&m->lock_object) == &lock_class_mtx_spin,
("thread_lock() of sleep mutex %s @ %s:%d",
m->lock_object.lo_name, file, line));
if (mtx_owned(m))
KASSERT((m->lock_object.lo_flags & LO_RECURSABLE) != 0,
("thread_lock: recursed on non-recursive mutex %s @ %s:%d\n",
m->lock_object.lo_name, file, line));
WITNESS_CHECKORDER(&m->lock_object,
opts | LOP_NEWORDER | LOP_EXCLUSIVE, file, line, NULL);
while (!_mtx_obtain_lock(m, tid)) {
if (m->mtx_lock == tid) {
m->mtx_recurse++;
break;
}
#ifdef HWPMC_HOOKS
PMC_SOFT_CALL( , , lock, failed);
#endif
lock_profile_obtain_lock_failed(&m->lock_object,
&contested, &waittime);
/* Give interrupts a chance while we spin. */
spinlock_exit();
while (m->mtx_lock != MTX_UNOWNED) {
if (i++ < 10000000)
cpu_spinwait();
else if (i < 60000000 ||
kdb_active || panicstr != NULL)
DELAY(1);
else
_mtx_lock_spin_failed(m);
cpu_spinwait();
if (m != td->td_lock)
goto retry;
}
spinlock_enter();
}
if (m == td->td_lock)
break;
__mtx_unlock_spin(m); /* does spinlock_exit() */
}
#ifdef KDTRACE_HOOKS
spin_time += lockstat_nsecs(&m->lock_object);
#endif
if (m->mtx_recurse == 0)
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(spin__acquire, m,
contested, waittime, file, line);
LOCK_LOG_LOCK("LOCK", &m->lock_object, opts, m->mtx_recurse, file,
line);
WITNESS_LOCK(&m->lock_object, opts | LOP_EXCLUSIVE, file, line);
LOCKSTAT_RECORD1(thread__spin, m, spin_time);
}
