855 lines
19 KiB
C
855 lines
19 KiB
C
/* $NetBSD: kern_lwp.c,v 1.49 2006/11/03 19:46:03 ad Exp $ */
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/*-
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* Copyright (c) 2001 The NetBSD Foundation, Inc.
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* All rights reserved.
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*
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* This code is derived from software contributed to The NetBSD Foundation
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* by Nathan J. Williams.
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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 NetBSD
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* Foundation, Inc. and its contributors.
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* 4. Neither the name of The NetBSD Foundation nor the names of its
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* contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(0, "$NetBSD: kern_lwp.c,v 1.49 2006/11/03 19:46:03 ad Exp $");
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#include "opt_multiprocessor.h"
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#define _LWP_API_PRIVATE
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/pool.h>
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#include <sys/lock.h>
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#include <sys/proc.h>
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#include <sys/sa.h>
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#include <sys/savar.h>
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#include <sys/types.h>
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#include <sys/ucontext.h>
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#include <sys/resourcevar.h>
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#include <sys/mount.h>
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#include <sys/syscallargs.h>
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#include <sys/kauth.h>
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#include <uvm/uvm_extern.h>
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POOL_INIT(lwp_pool, sizeof(struct lwp), 0, 0, 0, "lwppl",
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&pool_allocator_nointr);
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POOL_INIT(lwp_uc_pool, sizeof(ucontext_t), 0, 0, 0, "lwpucpl",
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&pool_allocator_nointr);
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static specificdata_domain_t lwp_specificdata_domain;
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struct lwplist alllwp;
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#define LWP_DEBUG
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#ifdef LWP_DEBUG
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int lwp_debug = 0;
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#define DPRINTF(x) if (lwp_debug) printf x
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#else
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#define DPRINTF(x)
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#endif
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void
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lwpinit(void)
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{
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lwp_specificdata_domain = specificdata_domain_create();
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KASSERT(lwp_specificdata_domain != NULL);
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}
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/* ARGSUSED */
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int
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sys__lwp_create(struct lwp *l, void *v, register_t *retval)
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{
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struct sys__lwp_create_args /* {
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syscallarg(const ucontext_t *) ucp;
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syscallarg(u_long) flags;
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syscallarg(lwpid_t *) new_lwp;
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} */ *uap = v;
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struct proc *p = l->l_proc;
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struct lwp *l2;
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vaddr_t uaddr;
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boolean_t inmem;
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ucontext_t *newuc;
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int s, error;
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if (p->p_flag & P_SA)
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return EINVAL;
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newuc = pool_get(&lwp_uc_pool, PR_WAITOK);
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error = copyin(SCARG(uap, ucp), newuc,
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l->l_proc->p_emul->e_sa->sae_ucsize);
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if (error) {
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pool_put(&lwp_uc_pool, newuc);
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return (error);
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}
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/* XXX check against resource limits */
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inmem = uvm_uarea_alloc(&uaddr);
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if (__predict_false(uaddr == 0)) {
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pool_put(&lwp_uc_pool, newuc);
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return (ENOMEM);
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}
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/* XXX flags:
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* __LWP_ASLWP is probably needed for Solaris compat.
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*/
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newlwp(l, p, uaddr, inmem,
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SCARG(uap, flags) & LWP_DETACHED,
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NULL, 0, startlwp, newuc, &l2);
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if ((SCARG(uap, flags) & LWP_SUSPENDED) == 0) {
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SCHED_LOCK(s);
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l2->l_stat = LSRUN;
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setrunqueue(l2);
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p->p_nrlwps++;
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SCHED_UNLOCK(s);
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} else {
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l2->l_stat = LSSUSPENDED;
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}
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error = copyout(&l2->l_lid, SCARG(uap, new_lwp),
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sizeof(l2->l_lid));
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if (error) {
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/* XXX We should destroy the LWP. */
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return (error);
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}
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return (0);
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}
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int
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sys__lwp_exit(struct lwp *l, void *v, register_t *retval)
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{
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lwp_exit(l);
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/* NOTREACHED */
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return (0);
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}
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int
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sys__lwp_self(struct lwp *l, void *v, register_t *retval)
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{
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*retval = l->l_lid;
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return (0);
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}
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int
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sys__lwp_getprivate(struct lwp *l, void *v, register_t *retval)
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{
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*retval = (uintptr_t) l->l_private;
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return (0);
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}
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int
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sys__lwp_setprivate(struct lwp *l, void *v, register_t *retval)
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{
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struct sys__lwp_setprivate_args /* {
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syscallarg(void *) ptr;
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} */ *uap = v;
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l->l_private = SCARG(uap, ptr);
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return (0);
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}
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int
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sys__lwp_suspend(struct lwp *l, void *v, register_t *retval)
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{
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struct sys__lwp_suspend_args /* {
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syscallarg(lwpid_t) target;
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} */ *uap = v;
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int target_lid;
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struct proc *p = l->l_proc;
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struct lwp *t;
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struct lwp *t2;
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if (p->p_flag & P_SA)
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return EINVAL;
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target_lid = SCARG(uap, target);
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LIST_FOREACH(t, &p->p_lwps, l_sibling)
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if (t->l_lid == target_lid)
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break;
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if (t == NULL)
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return (ESRCH);
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if (t == l) {
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/*
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* Check for deadlock, which is only possible
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* when we're suspending ourself.
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*/
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LIST_FOREACH(t2, &p->p_lwps, l_sibling) {
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if ((t2 != l) && (t2->l_stat != LSSUSPENDED))
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break;
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}
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if (t2 == NULL) /* All other LWPs are suspended */
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return (EDEADLK);
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}
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return lwp_suspend(l, t);
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}
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inline int
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lwp_suspend(struct lwp *l, struct lwp *t)
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{
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struct proc *p = t->l_proc;
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int s;
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if (t == l) {
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SCHED_LOCK(s);
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KASSERT(l->l_stat == LSONPROC);
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l->l_stat = LSSUSPENDED;
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p->p_nrlwps--;
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/* XXX NJWLWP check if this makes sense here: */
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p->p_stats->p_ru.ru_nvcsw++;
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mi_switch(l, NULL);
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SCHED_ASSERT_UNLOCKED();
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splx(s);
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} else {
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switch (t->l_stat) {
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case LSSUSPENDED:
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return (0); /* _lwp_suspend() is idempotent */
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case LSRUN:
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SCHED_LOCK(s);
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remrunqueue(t);
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t->l_stat = LSSUSPENDED;
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p->p_nrlwps--;
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SCHED_UNLOCK(s);
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break;
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case LSSLEEP:
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t->l_stat = LSSUSPENDED;
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break;
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case LSIDL:
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case LSZOMB:
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return (EINTR); /* It's what Solaris does..... */
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case LSSTOP:
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panic("_lwp_suspend: Stopped LWP in running process!");
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break;
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case LSONPROC:
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/* XXX multiprocessor LWPs? Implement me! */
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return (EINVAL);
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}
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}
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return (0);
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}
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int
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sys__lwp_continue(struct lwp *l, void *v, register_t *retval)
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{
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struct sys__lwp_continue_args /* {
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syscallarg(lwpid_t) target;
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} */ *uap = v;
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int s, target_lid;
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struct proc *p = l->l_proc;
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struct lwp *t;
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if (p->p_flag & P_SA)
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return EINVAL;
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target_lid = SCARG(uap, target);
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LIST_FOREACH(t, &p->p_lwps, l_sibling)
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if (t->l_lid == target_lid)
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break;
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if (t == NULL)
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return (ESRCH);
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SCHED_LOCK(s);
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lwp_continue(t);
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SCHED_UNLOCK(s);
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return (0);
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}
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void
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lwp_continue(struct lwp *l)
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{
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DPRINTF(("lwp_continue of %d.%d (%s), state %d, wchan %p\n",
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l->l_proc->p_pid, l->l_lid, l->l_proc->p_comm, l->l_stat,
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l->l_wchan));
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if (l->l_stat != LSSUSPENDED)
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return;
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if (l->l_wchan == 0) {
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/* LWP was runnable before being suspended. */
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setrunnable(l);
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} else {
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/* LWP was sleeping before being suspended. */
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l->l_stat = LSSLEEP;
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}
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}
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int
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sys__lwp_wakeup(struct lwp *l, void *v, register_t *retval)
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{
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struct sys__lwp_wakeup_args /* {
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syscallarg(lwpid_t) target;
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} */ *uap = v;
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lwpid_t target_lid;
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struct lwp *t;
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struct proc *p;
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int error;
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int s;
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p = l->l_proc;
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target_lid = SCARG(uap, target);
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SCHED_LOCK(s);
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LIST_FOREACH(t, &p->p_lwps, l_sibling)
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if (t->l_lid == target_lid)
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break;
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if (t == NULL) {
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error = ESRCH;
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goto exit;
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}
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if (t->l_stat != LSSLEEP) {
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error = ENODEV;
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goto exit;
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}
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if ((t->l_flag & L_SINTR) == 0) {
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error = EBUSY;
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goto exit;
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}
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/*
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* Tell ltsleep to wakeup.
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*/
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t->l_flag |= L_CANCELLED;
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setrunnable(t);
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error = 0;
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exit:
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SCHED_UNLOCK(s);
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return error;
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}
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int
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sys__lwp_wait(struct lwp *l, void *v, register_t *retval)
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{
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struct sys__lwp_wait_args /* {
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syscallarg(lwpid_t) wait_for;
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syscallarg(lwpid_t *) departed;
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} */ *uap = v;
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int error;
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lwpid_t dep;
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error = lwp_wait1(l, SCARG(uap, wait_for), &dep, 0);
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if (error)
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return (error);
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if (SCARG(uap, departed)) {
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error = copyout(&dep, SCARG(uap, departed),
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sizeof(dep));
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if (error)
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return (error);
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}
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return (0);
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}
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int
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lwp_wait1(struct lwp *l, lwpid_t lid, lwpid_t *departed, int flags)
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{
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struct proc *p = l->l_proc;
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struct lwp *l2, *l3;
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int nfound, error, wpri;
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static const char waitstr1[] = "lwpwait";
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static const char waitstr2[] = "lwpwait2";
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DPRINTF(("lwp_wait1: %d.%d waiting for %d.\n",
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p->p_pid, l->l_lid, lid));
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if (lid == l->l_lid)
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return (EDEADLK); /* Waiting for ourselves makes no sense. */
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wpri = PWAIT |
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((flags & LWPWAIT_EXITCONTROL) ? PNOEXITERR : PCATCH);
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loop:
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nfound = 0;
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LIST_FOREACH(l2, &p->p_lwps, l_sibling) {
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if ((l2 == l) || (l2->l_flag & L_DETACHED) ||
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((lid != 0) && (lid != l2->l_lid)))
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continue;
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nfound++;
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if (l2->l_stat == LSZOMB) {
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if (departed)
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*departed = l2->l_lid;
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simple_lock(&p->p_lock);
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LIST_REMOVE(l2, l_sibling);
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p->p_nlwps--;
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p->p_nzlwps--;
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simple_unlock(&p->p_lock);
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/* XXX decrement limits */
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pool_put(&lwp_pool, l2);
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return (0);
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} else if (l2->l_stat == LSSLEEP ||
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l2->l_stat == LSSUSPENDED) {
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/* Deadlock checks.
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* 1. If all other LWPs are waiting for exits
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* or suspended, we would deadlock.
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*/
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LIST_FOREACH(l3, &p->p_lwps, l_sibling) {
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if (l3 != l && (l3->l_stat != LSSUSPENDED) &&
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!(l3->l_stat == LSSLEEP &&
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l3->l_wchan == (caddr_t) &p->p_nlwps))
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break;
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}
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if (l3 == NULL) /* Everyone else is waiting. */
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return (EDEADLK);
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/* XXX we'd like to check for a cycle of waiting
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* LWPs (specific LID waits, not any-LWP waits)
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* and detect that sort of deadlock, but we don't
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* have a good place to store the lwp that is
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* being waited for. wchan is already filled with
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* &p->p_nlwps, and putting the lwp address in
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* there for deadlock tracing would require
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* exiting LWPs to call wakeup on both their
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* own address and &p->p_nlwps, to get threads
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* sleeping on any LWP exiting.
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*
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* Revisit later. Maybe another auxillary
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* storage location associated with sleeping
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* is in order.
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*/
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}
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}
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if (nfound == 0)
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return (ESRCH);
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if ((error = tsleep((caddr_t) &p->p_nlwps, wpri,
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(lid != 0) ? waitstr1 : waitstr2, 0)) != 0)
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return (error);
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goto loop;
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}
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int
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newlwp(struct lwp *l1, struct proc *p2, vaddr_t uaddr, boolean_t inmem,
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int flags, void *stack, size_t stacksize,
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void (*func)(void *), void *arg, struct lwp **rnewlwpp)
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{
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struct lwp *l2;
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int s;
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l2 = pool_get(&lwp_pool, PR_WAITOK);
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l2->l_stat = LSIDL;
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l2->l_forw = l2->l_back = NULL;
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l2->l_proc = p2;
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lwp_initspecific(l2);
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memset(&l2->l_startzero, 0,
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(unsigned) ((caddr_t)&l2->l_endzero -
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(caddr_t)&l2->l_startzero));
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memcpy(&l2->l_startcopy, &l1->l_startcopy,
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(unsigned) ((caddr_t)&l2->l_endcopy -
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(caddr_t)&l2->l_startcopy));
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#if !defined(MULTIPROCESSOR)
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/*
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* In the single-processor case, all processes will always run
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* on the same CPU. So, initialize the child's CPU to the parent's
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* now. In the multiprocessor case, the child's CPU will be
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* initialized in the low-level context switch code when the
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* process runs.
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*/
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KASSERT(l1->l_cpu != NULL);
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l2->l_cpu = l1->l_cpu;
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#else
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/*
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* zero child's CPU pointer so we don't get trash.
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*/
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l2->l_cpu = NULL;
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#endif /* ! MULTIPROCESSOR */
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l2->l_flag = inmem ? L_INMEM : 0;
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l2->l_flag |= (flags & LWP_DETACHED) ? L_DETACHED : 0;
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lwp_update_creds(l2);
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callout_init(&l2->l_tsleep_ch);
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if (rnewlwpp != NULL)
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*rnewlwpp = l2;
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|
|
l2->l_addr = UAREA_TO_USER(uaddr);
|
|
uvm_lwp_fork(l1, l2, stack, stacksize, func,
|
|
(arg != NULL) ? arg : l2);
|
|
|
|
simple_lock(&p2->p_lock);
|
|
l2->l_lid = ++p2->p_nlwpid;
|
|
LIST_INSERT_HEAD(&p2->p_lwps, l2, l_sibling);
|
|
p2->p_nlwps++;
|
|
simple_unlock(&p2->p_lock);
|
|
|
|
/* XXX should be locked differently... */
|
|
s = proclist_lock_write();
|
|
LIST_INSERT_HEAD(&alllwp, l2, l_list);
|
|
proclist_unlock_write(s);
|
|
|
|
if (p2->p_emul->e_lwp_fork)
|
|
(*p2->p_emul->e_lwp_fork)(l1, l2);
|
|
|
|
return (0);
|
|
}
|
|
|
|
|
|
/*
|
|
* Quit the process. This will call cpu_exit, which will call cpu_switch,
|
|
* so this can only be used meaningfully if you're willing to switch away.
|
|
* Calling with l!=curlwp would be weird.
|
|
*/
|
|
void
|
|
lwp_exit(struct lwp *l)
|
|
{
|
|
struct proc *p = l->l_proc;
|
|
int s;
|
|
|
|
DPRINTF(("lwp_exit: %d.%d exiting.\n", p->p_pid, l->l_lid));
|
|
DPRINTF((" nlwps: %d nrlwps %d nzlwps: %d\n",
|
|
p->p_nlwps, p->p_nrlwps, p->p_nzlwps));
|
|
|
|
if (p->p_emul->e_lwp_exit)
|
|
(*p->p_emul->e_lwp_exit)(l);
|
|
|
|
/*
|
|
* If we are the last live LWP in a process, we need to exit
|
|
* the entire process (if that's not already going on). We do
|
|
* so with an exit status of zero, because it's a "controlled"
|
|
* exit, and because that's what Solaris does.
|
|
*
|
|
* Note: the last LWP's specificdata will be deleted here.
|
|
*/
|
|
if (((p->p_nlwps - p->p_nzlwps) == 1) && ((p->p_flag & P_WEXIT) == 0)) {
|
|
DPRINTF(("lwp_exit: %d.%d calling exit1()\n",
|
|
p->p_pid, l->l_lid));
|
|
exit1(l, 0);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
/* Delete the specificdata while it's still safe to sleep. */
|
|
specificdata_fini(lwp_specificdata_domain, &l->l_specdataref);
|
|
|
|
s = proclist_lock_write();
|
|
LIST_REMOVE(l, l_list);
|
|
proclist_unlock_write(s);
|
|
|
|
/*
|
|
* Release our cached credentials, and collate accounting flags.
|
|
*/
|
|
kauth_cred_free(l->l_cred);
|
|
simple_lock(&p->p_lock);
|
|
p->p_acflag |= l->l_acflag;
|
|
simple_unlock(&p->p_lock);
|
|
|
|
/* Free MD LWP resources */
|
|
#ifndef __NO_CPU_LWP_FREE
|
|
cpu_lwp_free(l, 0);
|
|
#endif
|
|
|
|
pmap_deactivate(l);
|
|
|
|
if (l->l_flag & L_DETACHED) {
|
|
simple_lock(&p->p_lock);
|
|
LIST_REMOVE(l, l_sibling);
|
|
p->p_nlwps--;
|
|
simple_unlock(&p->p_lock);
|
|
|
|
curlwp = NULL;
|
|
l->l_proc = NULL;
|
|
}
|
|
|
|
SCHED_LOCK(s);
|
|
p->p_nrlwps--;
|
|
l->l_stat = LSDEAD;
|
|
SCHED_UNLOCK(s);
|
|
|
|
/* This LWP no longer needs to hold the kernel lock. */
|
|
KERNEL_PROC_UNLOCK(l);
|
|
|
|
/* cpu_exit() will not return */
|
|
cpu_exit(l);
|
|
}
|
|
|
|
/*
|
|
* We are called from cpu_exit() once it is safe to schedule the
|
|
* dead process's resources to be freed (i.e., once we've switched to
|
|
* the idle PCB for the current CPU).
|
|
*
|
|
* NOTE: One must be careful with locking in this routine. It's
|
|
* called from a critical section in machine-dependent code, so
|
|
* we should refrain from changing any interrupt state.
|
|
*/
|
|
void
|
|
lwp_exit2(struct lwp *l)
|
|
{
|
|
struct proc *p;
|
|
|
|
KERNEL_LOCK(LK_EXCLUSIVE);
|
|
/*
|
|
* Free the VM resources we're still holding on to.
|
|
*/
|
|
uvm_lwp_exit(l);
|
|
|
|
if (l->l_flag & L_DETACHED) {
|
|
/* Nobody waits for detached LWPs. */
|
|
pool_put(&lwp_pool, l);
|
|
KERNEL_UNLOCK();
|
|
} else {
|
|
l->l_stat = LSZOMB;
|
|
p = l->l_proc;
|
|
p->p_nzlwps++;
|
|
wakeup(&p->p_nlwps);
|
|
KERNEL_UNLOCK();
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Pick a LWP to represent the process for those operations which
|
|
* want information about a "process" that is actually associated
|
|
* with a LWP.
|
|
*/
|
|
struct lwp *
|
|
proc_representative_lwp(struct proc *p)
|
|
{
|
|
struct lwp *l, *onproc, *running, *sleeping, *stopped, *suspended;
|
|
struct lwp *signalled;
|
|
|
|
/* Trivial case: only one LWP */
|
|
if (p->p_nlwps == 1)
|
|
return (LIST_FIRST(&p->p_lwps));
|
|
|
|
switch (p->p_stat) {
|
|
case SSTOP:
|
|
case SACTIVE:
|
|
/* Pick the most live LWP */
|
|
onproc = running = sleeping = stopped = suspended = NULL;
|
|
signalled = NULL;
|
|
LIST_FOREACH(l, &p->p_lwps, l_sibling) {
|
|
if (l->l_lid == p->p_sigctx.ps_lwp)
|
|
signalled = l;
|
|
switch (l->l_stat) {
|
|
case LSONPROC:
|
|
onproc = l;
|
|
break;
|
|
case LSRUN:
|
|
running = l;
|
|
break;
|
|
case LSSLEEP:
|
|
sleeping = l;
|
|
break;
|
|
case LSSTOP:
|
|
stopped = l;
|
|
break;
|
|
case LSSUSPENDED:
|
|
suspended = l;
|
|
break;
|
|
}
|
|
}
|
|
if (signalled)
|
|
return signalled;
|
|
if (onproc)
|
|
return onproc;
|
|
if (running)
|
|
return running;
|
|
if (sleeping)
|
|
return sleeping;
|
|
if (stopped)
|
|
return stopped;
|
|
if (suspended)
|
|
return suspended;
|
|
break;
|
|
case SZOMB:
|
|
/* Doesn't really matter... */
|
|
return (LIST_FIRST(&p->p_lwps));
|
|
#ifdef DIAGNOSTIC
|
|
case SIDL:
|
|
/* We have more than one LWP and we're in SIDL?
|
|
* How'd that happen?
|
|
*/
|
|
panic("Too many LWPs (%d) in SIDL process %d (%s)",
|
|
p->p_nrlwps, p->p_pid, p->p_comm);
|
|
default:
|
|
panic("Process %d (%s) in unknown state %d",
|
|
p->p_pid, p->p_comm, p->p_stat);
|
|
#endif
|
|
}
|
|
|
|
panic("proc_representative_lwp: couldn't find a lwp for process"
|
|
" %d (%s)", p->p_pid, p->p_comm);
|
|
/* NOTREACHED */
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Update an LWP's cached credentials to mirror the process' master copy.
|
|
*
|
|
* This happens early in the syscall path, on user trap, and on LWP
|
|
* creation. A long-running LWP can also voluntarily choose to update
|
|
* it's credentials by calling this routine. This may be called from
|
|
* LWP_CACHE_CREDS(), which checks l->l_cred != p->p_cred beforehand.
|
|
*/
|
|
void
|
|
lwp_update_creds(struct lwp *l)
|
|
{
|
|
kauth_cred_t oc;
|
|
struct proc *p;
|
|
|
|
p = l->l_proc;
|
|
oc = l->l_cred;
|
|
|
|
simple_lock(&p->p_lock);
|
|
kauth_cred_hold(p->p_cred);
|
|
l->l_cred = p->p_cred;
|
|
simple_unlock(&p->p_lock);
|
|
if (oc != NULL)
|
|
kauth_cred_free(oc);
|
|
}
|
|
|
|
/*
|
|
* lwp_specific_key_create --
|
|
* Create a key for subsystem lwp-specific data.
|
|
*/
|
|
int
|
|
lwp_specific_key_create(specificdata_key_t *keyp, specificdata_dtor_t dtor)
|
|
{
|
|
|
|
return (specificdata_key_create(lwp_specificdata_domain, keyp, dtor));
|
|
}
|
|
|
|
/*
|
|
* lwp_specific_key_delete --
|
|
* Delete a key for subsystem lwp-specific data.
|
|
*/
|
|
void
|
|
lwp_specific_key_delete(specificdata_key_t key)
|
|
{
|
|
|
|
specificdata_key_delete(lwp_specificdata_domain, key);
|
|
}
|
|
|
|
/*
|
|
* lwp_initspecific --
|
|
* Initialize an LWP's specificdata container.
|
|
*/
|
|
void
|
|
lwp_initspecific(struct lwp *l)
|
|
{
|
|
int error;
|
|
|
|
error = specificdata_init(lwp_specificdata_domain, &l->l_specdataref);
|
|
KASSERT(error == 0);
|
|
}
|
|
|
|
/*
|
|
* lwp_finispecific --
|
|
* Finalize an LWP's specificdata container.
|
|
*/
|
|
void
|
|
lwp_finispecific(struct lwp *l)
|
|
{
|
|
|
|
specificdata_fini(lwp_specificdata_domain, &l->l_specdataref);
|
|
}
|
|
|
|
/*
|
|
* lwp_getspecific --
|
|
* Return lwp-specific data corresponding to the specified key.
|
|
*
|
|
* Note: LWP specific data is NOT INTERLOCKED. An LWP should access
|
|
* only its OWN SPECIFIC DATA. If it is necessary to access another
|
|
* LWP's specifc data, care must be taken to ensure that doing so
|
|
* would not cause internal data structure inconsistency (i.e. caller
|
|
* can guarantee that the target LWP is not inside an lwp_getspecific()
|
|
* or lwp_setspecific() call).
|
|
*/
|
|
void *
|
|
lwp_getspecific(specificdata_key_t key)
|
|
{
|
|
|
|
return (specificdata_getspecific_unlocked(lwp_specificdata_domain,
|
|
&curlwp->l_specdataref, key));
|
|
}
|
|
|
|
void *
|
|
_lwp_getspecific_by_lwp(struct lwp *l, specificdata_key_t key)
|
|
{
|
|
|
|
return (specificdata_getspecific_unlocked(lwp_specificdata_domain,
|
|
&l->l_specdataref, key));
|
|
}
|
|
|
|
/*
|
|
* lwp_setspecific --
|
|
* Set lwp-specific data corresponding to the specified key.
|
|
*/
|
|
void
|
|
lwp_setspecific(specificdata_key_t key, void *data)
|
|
{
|
|
|
|
specificdata_setspecific(lwp_specificdata_domain,
|
|
&curlwp->l_specdataref, key, data);
|
|
}
|