int
lwp_unpark(lwpid_t target, const void *hint)
{
sleepq_t *sq;
wchan_t wchan;
int swapin;
kmutex_t *mp;
proc_t *p;
lwp_t *t;
/*
* Easy case: search for the LWP on the sleep queue. If
* it's parked, remove it from the queue and set running.
*/
p = curproc;
wchan = lwp_park_wchan(p, hint);
sq = sleeptab_lookup(&lwp_park_tab, wchan, &mp);
TAILQ_FOREACH(t, sq, l_sleepchain)
if (t->l_proc == p && t->l_lid == target)
break;
if (__predict_true(t != NULL)) {
swapin = sleepq_remove(sq, t);
mutex_spin_exit(mp);
if (swapin)
uvm_kick_scheduler();
return 0;
}
/*
* The LWP hasn't parked yet. Take the hit and mark the
* operation as pending.
*/
mutex_spin_exit(mp);
mutex_enter(p->p_lock);
if ((t = lwp_find(p, target)) == NULL) {
mutex_exit(p->p_lock);
return ESRCH;
}
/*
* It may not have parked yet, we may have raced, or it
* is parked on a different user sync object.
*/
lwp_lock(t);
if (t->l_syncobj == &lwp_park_sobj) {
/* Releases the LWP lock. */
(void)lwp_unsleep(t, true);
} else {
/*
* Set the operation pending. The next call to _lwp_park
* will return early.
*/
t->l_flag |= LW_UNPARKED;
lwp_unlock(t);
}
mutex_exit(p->p_lock);
return 0;
}
int
sys__lwp_unpark_all(struct lwp *l, const struct sys__lwp_unpark_all_args *uap, register_t *retval)
{
/* {
syscallarg(const lwpid_t *) targets;
syscallarg(size_t) ntargets;
syscallarg(const void *) hint;
} */
struct proc *p;
struct lwp *t;
sleepq_t *sq;
wchan_t wchan;
lwpid_t targets[32], *tp, *tpp, *tmax, target;
int swapin, error;
kmutex_t *mp;
u_int ntargets;
size_t sz;
p = l->l_proc;
ntargets = SCARG(uap, ntargets);
if (SCARG(uap, targets) == NULL) {
/*
* Let the caller know how much we are willing to do, and
* let it unpark the LWPs in blocks.
*/
*retval = LWP_UNPARK_MAX;
return 0;
}
if (ntargets > LWP_UNPARK_MAX || ntargets == 0)
return EINVAL;
/*
* Copy in the target array. If it's a small number of LWPs, then
* place the numbers on the stack.
*/
sz = sizeof(target) * ntargets;
if (sz <= sizeof(targets))
tp = targets;
else {
tp = kmem_alloc(sz, KM_SLEEP);
if (tp == NULL)
return ENOMEM;
}
error = copyin(SCARG(uap, targets), tp, sz);
if (error != 0) {
if (tp != targets) {
kmem_free(tp, sz);
}
return error;
}
swapin = 0;
wchan = lwp_park_wchan(p, SCARG(uap, hint));
sq = sleeptab_lookup(&lwp_park_tab, wchan, &mp);
for (tmax = tp + ntargets, tpp = tp; tpp < tmax; tpp++) {
target = *tpp;
/*
* Easy case: search for the LWP on the sleep queue. If
* it's parked, remove it from the queue and set running.
*/
TAILQ_FOREACH(t, sq, l_sleepchain)
if (t->l_proc == p && t->l_lid == target)
break;
if (t != NULL) {
swapin |= sleepq_remove(sq, t);
continue;
}
/*
* The LWP hasn't parked yet. Take the hit and
* mark the operation as pending.
*/
mutex_spin_exit(mp);
mutex_enter(p->p_lock);
if ((t = lwp_find(p, target)) == NULL) {
mutex_exit(p->p_lock);
mutex_spin_enter(mp);
continue;
}
lwp_lock(t);
/*
* It may not have parked yet, we may have raced, or
* it is parked on a different user sync object.
*/
if (t->l_syncobj == &lwp_park_sobj) {
/* Releases the LWP lock. */
(void)lwp_unsleep(t, true);
} else {
/*
* Set the operation pending. The next call to
* _lwp_park will return early.
*/
t->l_flag |= LW_UNPARKED;
lwp_unlock(t);
}
mutex_exit(p->p_lock);
mutex_spin_enter(mp);
}
mutex_spin_exit(mp);
if (tp != targets)
kmem_free(tp, sz);
if (swapin)
uvm_kick_scheduler();
return 0;
}
void
sleepq_enqueue(sleepq_t *sq, wchan_t wchan, const char *wmesg, syncobj_t *sobj)
{
struct lwp *l = curlwp;
#ifndef T2EX
if (__predict_false(sobj != &sleep_syncobj || strcmp(wemsg, "callout"))) {
#else
if (__predict_false(sobj != &sleep_syncobj || (strcmp(wmesg, "callout") != 0 && strcmp(wmesg, "select") != 0 && strcmp(wmesg, "pollsock") != 0))) {
#endif
panic("sleepq: unsupported enqueue");
}
/*
* Remove an LWP from a sleep queue if the LWP was deleted while in
* the waiting state.
*/
if ( l->l_sleepq != NULL && (l->l_stat & LSSLEEP) != 0 ) {
sleepq_remove(l->l_sleepq, l);
}
#ifndef T2EX
l->l_syncobj = sobj;
#endif
l->l_wchan = wchan;
l->l_sleepq = sq;
#ifndef T2EX
l->l_wmesg = wmesg;
l->l_slptime = 0;
#endif
l->l_stat = LSSLEEP;
#ifndef T2EX
l->l_sleeperr = 0;
#endif
TAILQ_INSERT_TAIL(sq, l, l_sleepchain);
}
int
sleepq_block(int timo, bool hatch)
{
struct lwp *l = curlwp;
int error = 0;
//KASSERT(timo == 0 && !hatch);
if (timo != 0) {
callout_schedule(&l->l_timeout_ch, timo);
}
#ifdef T2EX
if ( l->l_mutex != NULL ) {
mutex_exit(l->l_mutex);
}
#endif
mutex_enter(&sq_mtx);
while (l->l_wchan) {
if ( hatch ) {
error = cv_timedwait_sig( &sq_cv, &sq_mtx, timo );
}
else {
error = cv_timedwait( &sq_cv, &sq_mtx, timo );
}
if (error == EINTR) {
if (l->l_wchan) {
TAILQ_REMOVE(l->l_sleepq, l, l_sleepchain);
l->l_wchan = NULL;
l->l_sleepq = NULL;
}
}
}
mutex_exit(&sq_mtx);
#ifdef T2EX
l->l_mutex = &spc_lock;
#endif
if (timo != 0) {
/*
* Even if the callout appears to have fired, we need to
* stop it in order to synchronise with other CPUs.
*/
if (callout_halt(&l->l_timeout_ch, NULL)) {
error = EWOULDBLOCK;
}
}
return error;
}
#ifdef T2EX
lwp_t *
sleepq_wake(sleepq_t *sq, wchan_t wchan, u_int expected, kmutex_t *mp)
{
struct lwp *l;
bool found = false;
TAILQ_FOREACH(l, sq, l_sleepchain) {
if (l->l_wchan == wchan) {
found = true;
l->l_wchan = NULL;
}
}
if (found)
cv_broadcast(&sq_cv);
mutex_spin_exit(mp);
return NULL;
}
#else
/*
* sleepq_wake:
*
* Wake zero or more LWPs blocked on a single wait channel.
*/
lwp_t *
sleepq_wake(sleepq_t *sq, wchan_t wchan, u_int expected, kmutex_t *mp)
{
lwp_t *l, *next;
int swapin = 0;
KASSERT(mutex_owned(mp));
for (l = TAILQ_FIRST(sq); l != NULL; l = next) {
KASSERT(l->l_sleepq == sq);
KASSERT(l->l_mutex == mp);
next = TAILQ_NEXT(l, l_sleepchain);
if (l->l_wchan != wchan)
continue;
swapin |= sleepq_remove(sq, l);
if (--expected == 0)
break;
}
mutex_spin_exit(mp);
#if 0
/*
* If there are newly awakend threads that need to be swapped in,
* then kick the swapper into action.
*/
if (swapin)
uvm_kick_scheduler();
#endif
return l;
}
