freebsd-nq/sys/kern/kern_thr.c
Julian Elischer 2630e4c90c Give setrunqueue() and sched_add() more of a clue as to
where they are coming from and what is expected from them.

MFC after:	2 days
2004-09-01 02:11:28 +00:00

315 lines
7.1 KiB
C

/*
* Copyright (c) 2003, Jeffrey Roberson <jeff@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 unmodified, this list of conditions, and the following
* disclaimer.
* 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("$FreeBSD$");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/sched.h>
#include <sys/sysent.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/signalvar.h>
#include <sys/ucontext.h>
#include <sys/thr.h>
#include <machine/frame.h>
/*
* Back end support functions.
*/
void
thr_exit1(void)
{
struct ksegrp *kg;
struct thread *td;
struct kse *ke;
struct proc *p;
td = curthread;
p = td->td_proc;
kg = td->td_ksegrp;
ke = td->td_kse;
mtx_assert(&sched_lock, MA_OWNED);
PROC_LOCK_ASSERT(p, MA_OWNED);
KASSERT(!mtx_owned(&Giant), ("dying thread owns giant"));
/*
* Shutting down last thread in the proc. This will actually
* call exit() in the trampoline when it returns.
*/
if (p->p_numthreads == 1) {
PROC_UNLOCK(p);
return;
}
/*
* XXX Undelivered process wide signals should be reposted to the
* proc.
*/
/* Clean up cpu resources. */
cpu_thread_exit(td);
/* Unlink the thread from the process and kseg. */
thread_unlink(td);
ke->ke_state = KES_UNQUEUED;
ke->ke_thread = NULL;
kse_unlink(ke);
sched_exit_kse(TAILQ_NEXT(ke, ke_kglist), td);
/*
* If we were stopped while waiting for all threads to exit and this
* is the last thread wakeup the exiting thread.
*/
if (P_SHOULDSTOP(p) == P_STOPPED_SINGLE)
if (p->p_numthreads == 1)
thread_unsuspend_one(p->p_singlethread);
PROC_UNLOCK(p);
td->td_kse = NULL;
td->td_state = TDS_INACTIVE;
#if 0
td->td_proc = NULL;
#endif
td->td_ksegrp = NULL;
td->td_last_kse = NULL;
sched_exit_thread(TAILQ_NEXT(td, td_kglist), td);
thread_stash(td);
cpu_throw(td, choosethread());
}
#define RANGEOF(type, start, end) (offsetof(type, end) - offsetof(type, start))
/*
* System call interface.
*/
int
thr_create(struct thread *td, struct thr_create_args *uap)
/* ucontext_t *ctx, long *id, int flags */
{
struct kse *ke0;
struct thread *td0;
ucontext_t ctx;
long id;
int error;
if ((error = copyin(uap->ctx, &ctx, sizeof(ctx))))
return (error);
/* Initialize our td. */
td0 = thread_alloc();
/*
* Try the copyout as soon as we allocate the td so we don't have to
* tear things down in a failure case below.
*/
id = td0->td_tid;
if ((error = copyout(&id, uap->id, sizeof(long)))) {
thread_free(td0);
return (error);
}
bzero(&td0->td_startzero,
(unsigned)RANGEOF(struct thread, td_startzero, td_endzero));
bcopy(&td->td_startcopy, &td0->td_startcopy,
(unsigned) RANGEOF(struct thread, td_startcopy, td_endcopy));
td0->td_proc = td->td_proc;
PROC_LOCK(td->td_proc);
td0->td_sigmask = td->td_sigmask;
PROC_UNLOCK(td->td_proc);
td0->td_ucred = crhold(td->td_ucred);
/* Initialize our kse structure. */
ke0 = kse_alloc();
bzero(&ke0->ke_startzero,
RANGEOF(struct kse, ke_startzero, ke_endzero));
/* Set up our machine context. */
cpu_set_upcall(td0, td);
error = set_mcontext(td0, &ctx.uc_mcontext);
if (error != 0) {
kse_free(ke0);
thread_free(td0);
goto out;
}
/* Link the thread and kse into the ksegrp and make it runnable. */
mtx_lock_spin(&sched_lock);
thread_link(td0, td->td_ksegrp);
kse_link(ke0, td->td_ksegrp);
/* Bind this thread and kse together. */
td0->td_kse = ke0;
ke0->ke_thread = td0;
sched_fork_kse(td, ke0);
sched_fork_thread(td, td0);
TD_SET_CAN_RUN(td0);
if ((uap->flags & THR_SUSPENDED) == 0)
setrunqueue(td0, SRQ_BORING);
mtx_unlock_spin(&sched_lock);
out:
return (error);
}
int
thr_self(struct thread *td, struct thr_self_args *uap)
/* long *id */
{
long id;
int error;
id = td->td_tid;
if ((error = copyout(&id, uap->id, sizeof(long))))
return (error);
return (0);
}
int
thr_exit(struct thread *td, struct thr_exit_args *uap)
/* NULL */
{
struct proc *p;
p = td->td_proc;
PROC_LOCK(p);
mtx_lock_spin(&sched_lock);
/*
* This unlocks proc and doesn't return unless this is the last
* thread.
*/
thr_exit1();
mtx_unlock_spin(&sched_lock);
return (0);
}
int
thr_kill(struct thread *td, struct thr_kill_args *uap)
/* long id, int sig */
{
struct thread *ttd;
struct proc *p;
int error;
p = td->td_proc;
error = 0;
PROC_LOCK(p);
FOREACH_THREAD_IN_PROC(p, ttd) {
if (ttd->td_tid == uap->id)
break;
}
if (ttd == NULL) {
error = ESRCH;
goto out;
}
if (uap->sig == 0)
goto out;
if (!_SIG_VALID(uap->sig)) {
error = EINVAL;
goto out;
}
tdsignal(ttd, uap->sig, SIGTARGET_TD);
out:
PROC_UNLOCK(p);
return (error);
}
int
thr_suspend(struct thread *td, struct thr_suspend_args *uap)
/* const struct timespec *timeout */
{
struct timespec ts;
struct timeval tv;
int error;
int hz;
hz = 0;
error = 0;
if (uap->timeout != NULL) {
error = copyin((const void *)uap->timeout, (void *)&ts,
sizeof(struct timespec));
if (error != 0)
return (error);
if (ts.tv_nsec < 0 || ts.tv_nsec > 1000000000)
return (EINVAL);
if (ts.tv_sec == 0 && ts.tv_nsec == 0)
return (ETIMEDOUT);
TIMESPEC_TO_TIMEVAL(&tv, &ts);
hz = tvtohz(&tv);
}
PROC_LOCK(td->td_proc);
if ((td->td_flags & TDF_THRWAKEUP) == 0)
error = msleep((void *)td, &td->td_proc->p_mtx,
td->td_priority | PCATCH, "lthr", hz);
mtx_lock_spin(&sched_lock);
td->td_flags &= ~TDF_THRWAKEUP;
mtx_unlock_spin(&sched_lock);
PROC_UNLOCK(td->td_proc);
return (error == EWOULDBLOCK ? ETIMEDOUT : error);
}
int
thr_wake(struct thread *td, struct thr_wake_args *uap)
/* long id */
{
struct thread *ttd;
PROC_LOCK(td->td_proc);
FOREACH_THREAD_IN_PROC(td->td_proc, ttd) {
if (ttd->td_tid == uap->id)
break;
}
if (ttd == NULL) {
PROC_UNLOCK(td->td_proc);
return (ESRCH);
}
mtx_lock_spin(&sched_lock);
ttd->td_flags |= TDF_THRWAKEUP;
mtx_unlock_spin(&sched_lock);
wakeup_one((void *)ttd);
PROC_UNLOCK(td->td_proc);
return (0);
}