e4bcd25517
to WITNESS_WARN().
669 lines
18 KiB
C
669 lines
18 KiB
C
/*-
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* Copyright (c) 1982, 1986, 1990, 1991, 1993
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* The Regents of the University of California. All rights reserved.
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* (c) UNIX System Laboratories, Inc.
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* All or some portions of this file are derived from material licensed
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* to the University of California by American Telephone and Telegraph
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* Co. or Unix System Laboratories, Inc. and are reproduced herein with
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* the permission of UNIX System Laboratories, Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)kern_synch.c 8.9 (Berkeley) 5/19/95
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* $FreeBSD$
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*/
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#include "opt_ddb.h"
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#include "opt_ktrace.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/condvar.h>
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#include <sys/kernel.h>
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#include <sys/ktr.h>
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#include <sys/lock.h>
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#include <sys/mutex.h>
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#include <sys/proc.h>
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#include <sys/resourcevar.h>
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#include <sys/sched.h>
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#include <sys/signalvar.h>
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#include <sys/smp.h>
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#include <sys/sx.h>
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#include <sys/sysctl.h>
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#include <sys/sysproto.h>
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#include <sys/vmmeter.h>
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#ifdef DDB
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#include <ddb/ddb.h>
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#endif
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#ifdef KTRACE
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#include <sys/uio.h>
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#include <sys/ktrace.h>
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#endif
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#include <machine/cpu.h>
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static void sched_setup(void *dummy);
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SYSINIT(sched_setup, SI_SUB_KICK_SCHEDULER, SI_ORDER_FIRST, sched_setup, NULL)
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int hogticks;
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int lbolt;
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static struct callout loadav_callout;
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static struct callout lbolt_callout;
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struct loadavg averunnable =
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{ {0, 0, 0}, FSCALE }; /* load average, of runnable procs */
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/*
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* Constants for averages over 1, 5, and 15 minutes
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* when sampling at 5 second intervals.
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*/
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static fixpt_t cexp[3] = {
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0.9200444146293232 * FSCALE, /* exp(-1/12) */
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0.9834714538216174 * FSCALE, /* exp(-1/60) */
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0.9944598480048967 * FSCALE, /* exp(-1/180) */
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};
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/* kernel uses `FSCALE', userland (SHOULD) use kern.fscale */
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static int fscale __unused = FSCALE;
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SYSCTL_INT(_kern, OID_AUTO, fscale, CTLFLAG_RD, 0, FSCALE, "");
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static void endtsleep(void *);
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static void loadav(void *arg);
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static void lboltcb(void *arg);
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/*
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* We're only looking at 7 bits of the address; everything is
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* aligned to 4, lots of things are aligned to greater powers
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* of 2. Shift right by 8, i.e. drop the bottom 256 worth.
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*/
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#define TABLESIZE 128
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static TAILQ_HEAD(slpquehead, thread) slpque[TABLESIZE];
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#define LOOKUP(x) (((intptr_t)(x) >> 8) & (TABLESIZE - 1))
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void
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sleepinit(void)
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{
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int i;
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hogticks = (hz / 10) * 2; /* Default only. */
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for (i = 0; i < TABLESIZE; i++)
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TAILQ_INIT(&slpque[i]);
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}
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/*
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* General sleep call. Suspends the current process until a wakeup is
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* performed on the specified identifier. The process will then be made
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* runnable with the specified priority. Sleeps at most timo/hz seconds
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* (0 means no timeout). If pri includes PCATCH flag, signals are checked
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* before and after sleeping, else signals are not checked. Returns 0 if
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* awakened, EWOULDBLOCK if the timeout expires. If PCATCH is set and a
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* signal needs to be delivered, ERESTART is returned if the current system
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* call should be restarted if possible, and EINTR is returned if the system
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* call should be interrupted by the signal (return EINTR).
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*
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* The mutex argument is exited before the caller is suspended, and
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* entered before msleep returns. If priority includes the PDROP
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* flag the mutex is not entered before returning.
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*/
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int
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msleep(ident, mtx, priority, wmesg, timo)
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void *ident;
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struct mtx *mtx;
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int priority, timo;
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const char *wmesg;
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{
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struct thread *td = curthread;
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struct proc *p = td->td_proc;
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int sig, catch = priority & PCATCH;
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int rval = 0;
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WITNESS_SAVE_DECL(mtx);
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#ifdef KTRACE
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if (KTRPOINT(td, KTR_CSW))
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ktrcsw(1, 0);
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#endif
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WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, &mtx->mtx_object,
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"Sleeping on \"%s\"", wmesg);
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KASSERT(timo != 0 || mtx_owned(&Giant) || mtx != NULL,
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("sleeping without a mutex"));
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/*
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* If we are capable of async syscalls and there isn't already
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* another one ready to return, start a new thread
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* and queue it as ready to run. Note that there is danger here
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* because we need to make sure that we don't sleep allocating
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* the thread (recursion here might be bad).
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* Hence the TDF_INMSLEEP flag.
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*/
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if (p->p_flag & P_THREADED) {
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/*
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* Just don't bother if we are exiting
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* and not the exiting thread or thread was marked as
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* interrupted.
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*/
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if (catch &&
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(((p->p_flag & P_WEXIT) && (p->p_singlethread != td)) ||
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(td->td_flags & TDF_INTERRUPT))) {
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td->td_flags &= ~TDF_INTERRUPT;
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return (EINTR);
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}
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}
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mtx_lock_spin(&sched_lock);
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if (cold ) {
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/*
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* During autoconfiguration, just give interrupts
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* a chance, then just return.
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* Don't run any other procs or panic below,
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* in case this is the idle process and already asleep.
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*/
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if (mtx != NULL && priority & PDROP)
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mtx_unlock(mtx);
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mtx_unlock_spin(&sched_lock);
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return (0);
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}
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DROP_GIANT();
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if (mtx != NULL) {
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mtx_assert(mtx, MA_OWNED | MA_NOTRECURSED);
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WITNESS_SAVE(&mtx->mtx_object, mtx);
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mtx_unlock(mtx);
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if (priority & PDROP)
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mtx = NULL;
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}
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KASSERT(p != NULL, ("msleep1"));
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KASSERT(ident != NULL && TD_IS_RUNNING(td), ("msleep"));
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CTR5(KTR_PROC, "msleep: thread %p (pid %d, %s) on %s (%p)",
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td, p->p_pid, p->p_comm, wmesg, ident);
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td->td_wchan = ident;
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td->td_wmesg = wmesg;
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TAILQ_INSERT_TAIL(&slpque[LOOKUP(ident)], td, td_slpq);
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TD_SET_ON_SLEEPQ(td);
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if (timo)
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callout_reset(&td->td_slpcallout, timo, endtsleep, td);
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/*
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* We put ourselves on the sleep queue and start our timeout
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* before calling thread_suspend_check, as we could stop there, and
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* a wakeup or a SIGCONT (or both) could occur while we were stopped.
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* without resuming us, thus we must be ready for sleep
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* when cursig is called. If the wakeup happens while we're
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* stopped, td->td_wchan will be 0 upon return from cursig.
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*/
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if (catch) {
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CTR3(KTR_PROC, "msleep caught: thread %p (pid %d, %s)", td,
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p->p_pid, p->p_comm);
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td->td_flags |= TDF_SINTR;
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mtx_unlock_spin(&sched_lock);
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PROC_LOCK(p);
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sig = cursig(td);
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if (sig == 0 && thread_suspend_check(1))
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sig = SIGSTOP;
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mtx_lock_spin(&sched_lock);
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PROC_UNLOCK(p);
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if (sig != 0) {
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if (TD_ON_SLEEPQ(td))
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unsleep(td);
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} else if (!TD_ON_SLEEPQ(td))
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catch = 0;
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} else
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sig = 0;
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/*
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* Let the scheduler know we're about to voluntarily go to sleep.
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*/
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sched_sleep(td, priority & PRIMASK);
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if (TD_ON_SLEEPQ(td)) {
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p->p_stats->p_ru.ru_nvcsw++;
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TD_SET_SLEEPING(td);
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mi_switch();
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}
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/*
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* We're awake from voluntary sleep.
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*/
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CTR3(KTR_PROC, "msleep resume: thread %p (pid %d, %s)", td, p->p_pid,
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p->p_comm);
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KASSERT(TD_IS_RUNNING(td), ("running but not TDS_RUNNING"));
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td->td_flags &= ~TDF_SINTR;
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if (td->td_flags & TDF_TIMEOUT) {
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td->td_flags &= ~TDF_TIMEOUT;
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if (sig == 0)
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rval = EWOULDBLOCK;
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} else if (td->td_flags & TDF_TIMOFAIL) {
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td->td_flags &= ~TDF_TIMOFAIL;
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} else if (timo && callout_stop(&td->td_slpcallout) == 0) {
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/*
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* This isn't supposed to be pretty. If we are here, then
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* the endtsleep() callout is currently executing on another
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* CPU and is either spinning on the sched_lock or will be
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* soon. If we don't synchronize here, there is a chance
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* that this process may msleep() again before the callout
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* has a chance to run and the callout may end up waking up
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* the wrong msleep(). Yuck.
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*/
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TD_SET_SLEEPING(td);
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p->p_stats->p_ru.ru_nivcsw++;
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mi_switch();
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td->td_flags &= ~TDF_TIMOFAIL;
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}
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if ((td->td_flags & TDF_INTERRUPT) && (priority & PCATCH) &&
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(rval == 0)) {
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td->td_flags &= ~TDF_INTERRUPT;
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rval = EINTR;
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}
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mtx_unlock_spin(&sched_lock);
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if (rval == 0 && catch) {
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PROC_LOCK(p);
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/* XXX: shouldn't we always be calling cursig() */
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if (sig != 0 || (sig = cursig(td))) {
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if (SIGISMEMBER(p->p_sigacts->ps_sigintr, sig))
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rval = EINTR;
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else
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|
rval = ERESTART;
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}
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|
PROC_UNLOCK(p);
|
|
}
|
|
#ifdef KTRACE
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if (KTRPOINT(td, KTR_CSW))
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ktrcsw(0, 0);
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#endif
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PICKUP_GIANT();
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if (mtx != NULL) {
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mtx_lock(mtx);
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WITNESS_RESTORE(&mtx->mtx_object, mtx);
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}
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return (rval);
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}
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|
|
/*
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|
* Implement timeout for msleep()
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*
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* If process hasn't been awakened (wchan non-zero),
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* set timeout flag and undo the sleep. If proc
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* is stopped, just unsleep so it will remain stopped.
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* MP-safe, called without the Giant mutex.
|
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*/
|
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static void
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endtsleep(arg)
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void *arg;
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{
|
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register struct thread *td = arg;
|
|
|
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CTR3(KTR_PROC, "endtsleep: thread %p (pid %d, %s)",
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td, td->td_proc->p_pid, td->td_proc->p_comm);
|
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mtx_lock_spin(&sched_lock);
|
|
/*
|
|
* This is the other half of the synchronization with msleep()
|
|
* described above. If the TDS_TIMEOUT flag is set, we lost the
|
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* race and just need to put the process back on the runqueue.
|
|
*/
|
|
if (TD_ON_SLEEPQ(td)) {
|
|
TAILQ_REMOVE(&slpque[LOOKUP(td->td_wchan)], td, td_slpq);
|
|
TD_CLR_ON_SLEEPQ(td);
|
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td->td_flags |= TDF_TIMEOUT;
|
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td->td_wmesg = NULL;
|
|
} else {
|
|
td->td_flags |= TDF_TIMOFAIL;
|
|
}
|
|
TD_CLR_SLEEPING(td);
|
|
setrunnable(td);
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
|
|
/*
|
|
* Abort a thread, as if an interrupt had occured. Only abort
|
|
* interruptable waits (unfortunatly it isn't only safe to abort others).
|
|
* This is about identical to cv_abort().
|
|
* Think about merging them?
|
|
* Also, whatever the signal code does...
|
|
*/
|
|
void
|
|
abortsleep(struct thread *td)
|
|
{
|
|
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
/*
|
|
* If the TDF_TIMEOUT flag is set, just leave. A
|
|
* timeout is scheduled anyhow.
|
|
*/
|
|
if ((td->td_flags & (TDF_TIMEOUT | TDF_SINTR)) == TDF_SINTR) {
|
|
if (TD_ON_SLEEPQ(td)) {
|
|
unsleep(td);
|
|
TD_CLR_SLEEPING(td);
|
|
setrunnable(td);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Remove a process from its wait queue
|
|
*/
|
|
void
|
|
unsleep(struct thread *td)
|
|
{
|
|
|
|
mtx_lock_spin(&sched_lock);
|
|
if (TD_ON_SLEEPQ(td)) {
|
|
TAILQ_REMOVE(&slpque[LOOKUP(td->td_wchan)], td, td_slpq);
|
|
TD_CLR_ON_SLEEPQ(td);
|
|
td->td_wmesg = NULL;
|
|
}
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
|
|
/*
|
|
* Make all processes sleeping on the specified identifier runnable.
|
|
*/
|
|
void
|
|
wakeup(ident)
|
|
register void *ident;
|
|
{
|
|
register struct slpquehead *qp;
|
|
register struct thread *td;
|
|
struct thread *ntd;
|
|
struct proc *p;
|
|
|
|
mtx_lock_spin(&sched_lock);
|
|
qp = &slpque[LOOKUP(ident)];
|
|
restart:
|
|
for (td = TAILQ_FIRST(qp); td != NULL; td = ntd) {
|
|
ntd = TAILQ_NEXT(td, td_slpq);
|
|
if (td->td_wchan == ident) {
|
|
unsleep(td);
|
|
TD_CLR_SLEEPING(td);
|
|
setrunnable(td);
|
|
p = td->td_proc;
|
|
CTR3(KTR_PROC,"wakeup: thread %p (pid %d, %s)",
|
|
td, p->p_pid, p->p_comm);
|
|
goto restart;
|
|
}
|
|
}
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
|
|
/*
|
|
* Make a process sleeping on the specified identifier runnable.
|
|
* May wake more than one process if a target process is currently
|
|
* swapped out.
|
|
*/
|
|
void
|
|
wakeup_one(ident)
|
|
register void *ident;
|
|
{
|
|
register struct slpquehead *qp;
|
|
register struct thread *td;
|
|
register struct proc *p;
|
|
struct thread *ntd;
|
|
|
|
mtx_lock_spin(&sched_lock);
|
|
qp = &slpque[LOOKUP(ident)];
|
|
for (td = TAILQ_FIRST(qp); td != NULL; td = ntd) {
|
|
ntd = TAILQ_NEXT(td, td_slpq);
|
|
if (td->td_wchan == ident) {
|
|
unsleep(td);
|
|
TD_CLR_SLEEPING(td);
|
|
setrunnable(td);
|
|
p = td->td_proc;
|
|
CTR3(KTR_PROC,"wakeup1: thread %p (pid %d, %s)",
|
|
td, p->p_pid, p->p_comm);
|
|
break;
|
|
}
|
|
}
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
|
|
/*
|
|
* The machine independent parts of mi_switch().
|
|
*/
|
|
void
|
|
mi_switch(void)
|
|
{
|
|
struct bintime new_switchtime;
|
|
struct thread *td = curthread; /* XXX */
|
|
struct proc *p = td->td_proc; /* XXX */
|
|
u_int sched_nest;
|
|
|
|
mtx_assert(&sched_lock, MA_OWNED | MA_NOTRECURSED);
|
|
|
|
KASSERT(!TD_ON_RUNQ(td), ("mi_switch: called by old code"));
|
|
#ifdef INVARIANTS
|
|
if (!TD_ON_LOCK(td) &&
|
|
!TD_ON_RUNQ(td) &&
|
|
!TD_IS_RUNNING(td))
|
|
mtx_assert(&Giant, MA_NOTOWNED);
|
|
#endif
|
|
KASSERT(td->td_critnest == 1,
|
|
("mi_switch: switch in a critical section"));
|
|
|
|
/*
|
|
* Compute the amount of time during which the current
|
|
* process was running, and add that to its total so far.
|
|
*/
|
|
binuptime(&new_switchtime);
|
|
bintime_add(&p->p_runtime, &new_switchtime);
|
|
bintime_sub(&p->p_runtime, PCPU_PTR(switchtime));
|
|
|
|
#ifdef DDB
|
|
/*
|
|
* Don't perform context switches from the debugger.
|
|
*/
|
|
if (db_active) {
|
|
mtx_unlock_spin(&sched_lock);
|
|
db_print_backtrace();
|
|
db_error("Context switches not allowed in the debugger.");
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Check if the process exceeds its cpu resource allocation. If
|
|
* over max, arrange to kill the process in ast().
|
|
*/
|
|
if (p->p_cpulimit != RLIM_INFINITY &&
|
|
p->p_runtime.sec > p->p_cpulimit) {
|
|
p->p_sflag |= PS_XCPU;
|
|
td->td_flags |= TDF_ASTPENDING;
|
|
}
|
|
|
|
/*
|
|
* Finish up stats for outgoing thread.
|
|
*/
|
|
cnt.v_swtch++;
|
|
PCPU_SET(switchtime, new_switchtime);
|
|
CTR3(KTR_PROC, "mi_switch: old thread %p (pid %d, %s)", td, p->p_pid,
|
|
p->p_comm);
|
|
|
|
sched_nest = sched_lock.mtx_recurse;
|
|
sched_switchout(td);
|
|
|
|
cpu_switch(); /* SHAZAM!!*/
|
|
|
|
sched_lock.mtx_recurse = sched_nest;
|
|
sched_lock.mtx_lock = (uintptr_t)td;
|
|
sched_switchin(td);
|
|
|
|
/*
|
|
* Start setting up stats etc. for the incoming thread.
|
|
* Similar code in fork_exit() is returned to by cpu_switch()
|
|
* in the case of a new thread/process.
|
|
*/
|
|
CTR3(KTR_PROC, "mi_switch: new thread %p (pid %d, %s)", td, p->p_pid,
|
|
p->p_comm);
|
|
if (PCPU_GET(switchtime.sec) == 0)
|
|
binuptime(PCPU_PTR(switchtime));
|
|
PCPU_SET(switchticks, ticks);
|
|
|
|
/*
|
|
* Call the switchin function while still holding the scheduler lock
|
|
* (used by the idlezero code and the general page-zeroing code)
|
|
*/
|
|
if (td->td_switchin)
|
|
td->td_switchin();
|
|
|
|
/*
|
|
* If the last thread was exiting, finish cleaning it up.
|
|
*/
|
|
if ((td = PCPU_GET(deadthread))) {
|
|
PCPU_SET(deadthread, NULL);
|
|
thread_stash(td);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Change process state to be runnable,
|
|
* placing it on the run queue if it is in memory,
|
|
* and awakening the swapper if it isn't in memory.
|
|
*/
|
|
void
|
|
setrunnable(struct thread *td)
|
|
{
|
|
struct proc *p = td->td_proc;
|
|
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
switch (p->p_state) {
|
|
case PRS_ZOMBIE:
|
|
panic("setrunnable(1)");
|
|
default:
|
|
break;
|
|
}
|
|
switch (td->td_state) {
|
|
case TDS_RUNNING:
|
|
case TDS_RUNQ:
|
|
return;
|
|
case TDS_INHIBITED:
|
|
/*
|
|
* If we are only inhibited because we are swapped out
|
|
* then arange to swap in this process. Otherwise just return.
|
|
*/
|
|
if (td->td_inhibitors != TDI_SWAPPED)
|
|
return;
|
|
case TDS_CAN_RUN:
|
|
break;
|
|
default:
|
|
printf("state is 0x%x", td->td_state);
|
|
panic("setrunnable(2)");
|
|
}
|
|
if ((p->p_sflag & PS_INMEM) == 0) {
|
|
if ((p->p_sflag & PS_SWAPPINGIN) == 0) {
|
|
p->p_sflag |= PS_SWAPINREQ;
|
|
wakeup(&proc0);
|
|
}
|
|
} else
|
|
sched_wakeup(td);
|
|
}
|
|
|
|
/*
|
|
* Compute a tenex style load average of a quantity on
|
|
* 1, 5 and 15 minute intervals.
|
|
* XXXKSE Needs complete rewrite when correct info is available.
|
|
* Completely Bogus.. only works with 1:1 (but compiles ok now :-)
|
|
*/
|
|
static void
|
|
loadav(void *arg)
|
|
{
|
|
int i, nrun;
|
|
struct loadavg *avg;
|
|
struct proc *p;
|
|
struct thread *td;
|
|
|
|
avg = &averunnable;
|
|
sx_slock(&allproc_lock);
|
|
nrun = 0;
|
|
FOREACH_PROC_IN_SYSTEM(p) {
|
|
FOREACH_THREAD_IN_PROC(p, td) {
|
|
switch (td->td_state) {
|
|
case TDS_RUNQ:
|
|
case TDS_RUNNING:
|
|
if ((p->p_flag & P_NOLOAD) != 0)
|
|
goto nextproc;
|
|
nrun++; /* XXXKSE */
|
|
default:
|
|
break;
|
|
}
|
|
nextproc:
|
|
continue;
|
|
}
|
|
}
|
|
sx_sunlock(&allproc_lock);
|
|
for (i = 0; i < 3; i++)
|
|
avg->ldavg[i] = (cexp[i] * avg->ldavg[i] +
|
|
nrun * FSCALE * (FSCALE - cexp[i])) >> FSHIFT;
|
|
|
|
/*
|
|
* Schedule the next update to occur after 5 seconds, but add a
|
|
* random variation to avoid synchronisation with processes that
|
|
* run at regular intervals.
|
|
*/
|
|
callout_reset(&loadav_callout, hz * 4 + (int)(random() % (hz * 2 + 1)),
|
|
loadav, NULL);
|
|
}
|
|
|
|
static void
|
|
lboltcb(void *arg)
|
|
{
|
|
wakeup(&lbolt);
|
|
callout_reset(&lbolt_callout, hz, lboltcb, NULL);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static void
|
|
sched_setup(dummy)
|
|
void *dummy;
|
|
{
|
|
callout_init(&loadav_callout, 0);
|
|
callout_init(&lbolt_callout, 1);
|
|
|
|
/* Kick off timeout driven events by calling first time. */
|
|
loadav(NULL);
|
|
lboltcb(NULL);
|
|
}
|
|
|
|
/*
|
|
* General purpose yield system call
|
|
*/
|
|
int
|
|
yield(struct thread *td, struct yield_args *uap)
|
|
{
|
|
struct ksegrp *kg = td->td_ksegrp;
|
|
|
|
mtx_assert(&Giant, MA_NOTOWNED);
|
|
mtx_lock_spin(&sched_lock);
|
|
kg->kg_proc->p_stats->p_ru.ru_nvcsw++;
|
|
sched_prio(td, PRI_MAX_TIMESHARE);
|
|
mi_switch();
|
|
mtx_unlock_spin(&sched_lock);
|
|
td->td_retval[0] = 0;
|
|
|
|
return (0);
|
|
}
|
|
|