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21fc316430
in other codes. Add cpu_set_user_tls, use it to tweak user register and setup user TLS. I ever wanted to merge it into cpu_set_kse_upcall, but since cpu_set_kse_upcall is also used by M:N threads which may not need this feature, so I wrote a separated cpu_set_user_tls.
1477 lines
37 KiB
C
1477 lines
37 KiB
C
/*-
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* Copyright (C) 2001 Julian Elischer <julian@freebsd.org>.
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* All rights reserved.
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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(s), this list of conditions and the following disclaimer as
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* the first lines of this file unmodified other than the possible
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* addition of one or more copyright notices.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice(s), 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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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
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* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY
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* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* 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 SUCH
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* DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/kernel.h>
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#include <sys/imgact.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/ptrace.h>
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#include <sys/smp.h>
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#include <sys/syscallsubr.h>
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#include <sys/sysproto.h>
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#include <sys/sched.h>
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#include <sys/signalvar.h>
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#include <sys/sleepqueue.h>
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#include <sys/kse.h>
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#include <sys/ktr.h>
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#include <vm/uma.h>
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/*
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* KSEGRP related storage.
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*/
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static uma_zone_t upcall_zone;
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/* DEBUG ONLY */
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extern int virtual_cpu;
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extern int thread_debug;
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extern int max_threads_per_proc;
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extern int max_groups_per_proc;
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extern int max_threads_hits;
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extern struct mtx kse_zombie_lock;
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TAILQ_HEAD(, kse_upcall) zombie_upcalls =
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TAILQ_HEAD_INITIALIZER(zombie_upcalls);
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static int thread_update_usr_ticks(struct thread *td);
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static void thread_alloc_spare(struct thread *td);
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struct kse_upcall *
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upcall_alloc(void)
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{
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struct kse_upcall *ku;
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ku = uma_zalloc(upcall_zone, M_WAITOK | M_ZERO);
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return (ku);
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}
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void
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upcall_free(struct kse_upcall *ku)
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{
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uma_zfree(upcall_zone, ku);
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}
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void
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upcall_link(struct kse_upcall *ku, struct ksegrp *kg)
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{
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mtx_assert(&sched_lock, MA_OWNED);
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TAILQ_INSERT_TAIL(&kg->kg_upcalls, ku, ku_link);
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ku->ku_ksegrp = kg;
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kg->kg_numupcalls++;
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}
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void
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upcall_unlink(struct kse_upcall *ku)
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{
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struct ksegrp *kg = ku->ku_ksegrp;
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mtx_assert(&sched_lock, MA_OWNED);
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KASSERT(ku->ku_owner == NULL, ("%s: have owner", __func__));
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TAILQ_REMOVE(&kg->kg_upcalls, ku, ku_link);
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kg->kg_numupcalls--;
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upcall_stash(ku);
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}
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void
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upcall_remove(struct thread *td)
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{
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mtx_assert(&sched_lock, MA_OWNED);
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if (td->td_upcall != NULL) {
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td->td_upcall->ku_owner = NULL;
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upcall_unlink(td->td_upcall);
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td->td_upcall = NULL;
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}
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}
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#ifndef _SYS_SYSPROTO_H_
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struct kse_switchin_args {
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struct kse_thr_mailbox *tmbx;
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int flags;
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};
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#endif
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int
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kse_switchin(struct thread *td, struct kse_switchin_args *uap)
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{
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struct kse_thr_mailbox tmbx;
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struct kse_upcall *ku;
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int error;
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if ((ku = td->td_upcall) == NULL || TD_CAN_UNBIND(td))
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return (EINVAL);
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error = (uap->tmbx == NULL) ? EINVAL : 0;
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if (!error)
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error = copyin(uap->tmbx, &tmbx, sizeof(tmbx));
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if (!error && (uap->flags & KSE_SWITCHIN_SETTMBX))
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error = (suword(&ku->ku_mailbox->km_curthread,
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(long)uap->tmbx) != 0 ? EINVAL : 0);
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if (!error)
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error = set_mcontext(td, &tmbx.tm_context.uc_mcontext);
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if (!error) {
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suword32(&uap->tmbx->tm_lwp, td->td_tid);
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if (uap->flags & KSE_SWITCHIN_SETTMBX) {
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td->td_mailbox = uap->tmbx;
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td->td_pflags |= TDP_CAN_UNBIND;
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}
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if (td->td_proc->p_flag & P_TRACED) {
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if (tmbx.tm_dflags & TMDF_SSTEP)
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ptrace_single_step(td);
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else
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ptrace_clear_single_step(td);
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if (tmbx.tm_dflags & TMDF_SUSPEND) {
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mtx_lock_spin(&sched_lock);
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/* fuword can block, check again */
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if (td->td_upcall)
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ku->ku_flags |= KUF_DOUPCALL;
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mtx_unlock_spin(&sched_lock);
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}
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}
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}
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return ((error == 0) ? EJUSTRETURN : error);
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}
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/*
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struct kse_thr_interrupt_args {
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struct kse_thr_mailbox * tmbx;
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int cmd;
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long data;
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};
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*/
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int
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kse_thr_interrupt(struct thread *td, struct kse_thr_interrupt_args *uap)
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{
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struct kse_execve_args args;
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struct image_args iargs;
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struct proc *p;
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struct thread *td2;
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struct kse_upcall *ku;
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struct kse_thr_mailbox *tmbx;
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uint32_t flags;
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int error;
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p = td->td_proc;
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if (!(p->p_flag & P_SA))
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return (EINVAL);
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switch (uap->cmd) {
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case KSE_INTR_SENDSIG:
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if (uap->data < 0 || uap->data > _SIG_MAXSIG)
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return (EINVAL);
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case KSE_INTR_INTERRUPT:
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case KSE_INTR_RESTART:
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PROC_LOCK(p);
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mtx_lock_spin(&sched_lock);
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FOREACH_THREAD_IN_PROC(p, td2) {
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if (td2->td_mailbox == uap->tmbx)
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break;
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}
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if (td2 == NULL) {
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mtx_unlock_spin(&sched_lock);
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PROC_UNLOCK(p);
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return (ESRCH);
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}
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if (uap->cmd == KSE_INTR_SENDSIG) {
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if (uap->data > 0) {
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td2->td_flags &= ~TDF_INTERRUPT;
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mtx_unlock_spin(&sched_lock);
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tdsignal(td2, (int)uap->data, SIGTARGET_TD);
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} else {
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mtx_unlock_spin(&sched_lock);
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}
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} else {
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td2->td_flags |= TDF_INTERRUPT | TDF_ASTPENDING;
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if (TD_CAN_UNBIND(td2))
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td2->td_upcall->ku_flags |= KUF_DOUPCALL;
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if (uap->cmd == KSE_INTR_INTERRUPT)
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td2->td_intrval = EINTR;
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else
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td2->td_intrval = ERESTART;
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if (TD_ON_SLEEPQ(td2) && (td2->td_flags & TDF_SINTR))
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sleepq_abort(td2);
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mtx_unlock_spin(&sched_lock);
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}
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PROC_UNLOCK(p);
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break;
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case KSE_INTR_SIGEXIT:
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if (uap->data < 1 || uap->data > _SIG_MAXSIG)
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return (EINVAL);
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PROC_LOCK(p);
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sigexit(td, (int)uap->data);
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break;
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case KSE_INTR_DBSUSPEND:
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/* this sub-function is only for bound thread */
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if (td->td_pflags & TDP_SA)
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return (EINVAL);
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ku = td->td_upcall;
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tmbx = (void *)fuword((void *)&ku->ku_mailbox->km_curthread);
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if (tmbx == NULL || tmbx == (void *)-1)
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return (EINVAL);
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flags = 0;
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while ((p->p_flag & P_TRACED) && !(p->p_flag & P_SINGLE_EXIT)) {
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flags = fuword32(&tmbx->tm_dflags);
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if (!(flags & TMDF_SUSPEND))
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break;
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PROC_LOCK(p);
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mtx_lock_spin(&sched_lock);
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thread_stopped(p);
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thread_suspend_one(td);
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PROC_UNLOCK(p);
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mi_switch(SW_VOL, NULL);
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mtx_unlock_spin(&sched_lock);
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}
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return (0);
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case KSE_INTR_EXECVE:
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error = copyin((void *)uap->data, &args, sizeof(args));
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if (error)
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return (error);
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error = exec_copyin_args(&iargs, args.path, UIO_USERSPACE,
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args.argv, args.envp);
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if (error == 0)
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error = kern_execve(td, &iargs, NULL);
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exec_free_args(&iargs);
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if (error == 0) {
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PROC_LOCK(p);
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SIGSETOR(td->td_siglist, args.sigpend);
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PROC_UNLOCK(p);
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kern_sigprocmask(td, SIG_SETMASK, &args.sigmask, NULL,
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0);
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}
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return (error);
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default:
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return (EINVAL);
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}
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return (0);
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}
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/*
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struct kse_exit_args {
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register_t dummy;
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};
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*/
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int
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kse_exit(struct thread *td, struct kse_exit_args *uap)
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{
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struct proc *p;
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struct ksegrp *kg;
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struct kse_upcall *ku, *ku2;
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int error, count;
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p = td->td_proc;
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/*
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* Ensure that this is only called from the UTS
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*/
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if ((ku = td->td_upcall) == NULL || TD_CAN_UNBIND(td))
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return (EINVAL);
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kg = td->td_ksegrp;
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count = 0;
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/*
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* Calculate the existing non-exiting upcalls in this ksegroup.
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* If we are the last upcall but there are still other threads,
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* then do not exit. We need the other threads to be able to
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* complete whatever they are doing.
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* XXX This relies on the userland knowing what to do if we return.
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* It may be a better choice to convert ourselves into a kse_release
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* ( or similar) and wait in the kernel to be needed.
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*/
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PROC_LOCK(p);
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mtx_lock_spin(&sched_lock);
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FOREACH_UPCALL_IN_GROUP(kg, ku2) {
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if (ku2->ku_flags & KUF_EXITING)
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count++;
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}
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if ((kg->kg_numupcalls - count) == 1 &&
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(kg->kg_numthreads > 1)) {
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mtx_unlock_spin(&sched_lock);
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PROC_UNLOCK(p);
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return (EDEADLK);
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}
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ku->ku_flags |= KUF_EXITING;
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mtx_unlock_spin(&sched_lock);
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PROC_UNLOCK(p);
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/*
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* Mark the UTS mailbox as having been finished with.
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* If that fails then just go for a segfault.
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* XXX need to check it that can be deliverred without a mailbox.
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*/
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error = suword32(&ku->ku_mailbox->km_flags, ku->ku_mflags|KMF_DONE);
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if (!(td->td_pflags & TDP_SA))
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if (suword32(&td->td_mailbox->tm_lwp, 0))
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error = EFAULT;
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PROC_LOCK(p);
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if (error)
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psignal(p, SIGSEGV);
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mtx_lock_spin(&sched_lock);
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upcall_remove(td);
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if (p->p_numthreads != 1) {
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/*
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* If we are not the last thread, but we are the last
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* thread in this ksegrp, then by definition this is not
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* the last group and we need to clean it up as well.
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* thread_exit will clean up the kseg as needed.
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*/
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thread_stopped(p);
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thread_exit();
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/* NOTREACHED */
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}
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/*
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* This is the last thread. Just return to the user.
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* We know that there is only one ksegrp too, as any others
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* would have been discarded in previous calls to thread_exit().
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* Effectively we have left threading mode..
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* The only real thing left to do is ensure that the
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* scheduler sets out concurrency back to 1 as that may be a
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* resource leak otherwise.
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* This is an A[PB]I issue.. what SHOULD we do?
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* One possibility is to return to the user. It may not cope well.
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* The other possibility would be to let the process exit.
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*/
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thread_unthread(td);
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mtx_unlock_spin(&sched_lock);
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PROC_UNLOCK(p);
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#if 1
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return (0);
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#else
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exit1(td, 0);
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#endif
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}
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/*
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* Either becomes an upcall or waits for an awakening event and
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* then becomes an upcall. Only error cases return.
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*/
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/*
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struct kse_release_args {
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struct timespec *timeout;
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};
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*/
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int
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kse_release(struct thread *td, struct kse_release_args *uap)
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{
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struct proc *p;
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struct ksegrp *kg;
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struct kse_upcall *ku;
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struct timespec timeout;
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struct timeval tv;
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sigset_t sigset;
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int error;
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p = td->td_proc;
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kg = td->td_ksegrp;
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if ((ku = td->td_upcall) == NULL || TD_CAN_UNBIND(td))
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return (EINVAL);
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if (uap->timeout != NULL) {
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if ((error = copyin(uap->timeout, &timeout, sizeof(timeout))))
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return (error);
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TIMESPEC_TO_TIMEVAL(&tv, &timeout);
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}
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if (td->td_pflags & TDP_SA)
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td->td_pflags |= TDP_UPCALLING;
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else {
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ku->ku_mflags = fuword32(&ku->ku_mailbox->km_flags);
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if (ku->ku_mflags == -1) {
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PROC_LOCK(p);
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sigexit(td, SIGSEGV);
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}
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}
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PROC_LOCK(p);
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if (ku->ku_mflags & KMF_WAITSIGEVENT) {
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/* UTS wants to wait for signal event */
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if (!(p->p_flag & P_SIGEVENT) &&
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!(ku->ku_flags & KUF_DOUPCALL)) {
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td->td_kflags |= TDK_KSERELSIG;
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error = msleep(&p->p_siglist, &p->p_mtx, PPAUSE|PCATCH,
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"ksesigwait", (uap->timeout ? tvtohz(&tv) : 0));
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td->td_kflags &= ~(TDK_KSERELSIG | TDK_WAKEUP);
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}
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p->p_flag &= ~P_SIGEVENT;
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sigset = p->p_siglist;
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PROC_UNLOCK(p);
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error = copyout(&sigset, &ku->ku_mailbox->km_sigscaught,
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sizeof(sigset));
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} else {
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if ((ku->ku_flags & KUF_DOUPCALL) == 0 &&
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((ku->ku_mflags & KMF_NOCOMPLETED) ||
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(kg->kg_completed == NULL))) {
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kg->kg_upsleeps++;
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td->td_kflags |= TDK_KSEREL;
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error = msleep(&kg->kg_completed, &p->p_mtx,
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PPAUSE|PCATCH, "kserel",
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(uap->timeout ? tvtohz(&tv) : 0));
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td->td_kflags &= ~(TDK_KSEREL | TDK_WAKEUP);
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kg->kg_upsleeps--;
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}
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PROC_UNLOCK(p);
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}
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if (ku->ku_flags & KUF_DOUPCALL) {
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mtx_lock_spin(&sched_lock);
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ku->ku_flags &= ~KUF_DOUPCALL;
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mtx_unlock_spin(&sched_lock);
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}
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return (0);
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}
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|
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/* struct kse_wakeup_args {
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struct kse_mailbox *mbx;
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}; */
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|
int
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kse_wakeup(struct thread *td, struct kse_wakeup_args *uap)
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{
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struct proc *p;
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struct ksegrp *kg;
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struct kse_upcall *ku;
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struct thread *td2;
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p = td->td_proc;
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td2 = NULL;
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ku = NULL;
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/* KSE-enabled processes only, please. */
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if (!(p->p_flag & P_SA))
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return (EINVAL);
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PROC_LOCK(p);
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mtx_lock_spin(&sched_lock);
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if (uap->mbx) {
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FOREACH_KSEGRP_IN_PROC(p, kg) {
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FOREACH_UPCALL_IN_GROUP(kg, ku) {
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if (ku->ku_mailbox == uap->mbx)
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break;
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}
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if (ku)
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break;
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}
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} else {
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kg = td->td_ksegrp;
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if (kg->kg_upsleeps) {
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mtx_unlock_spin(&sched_lock);
|
|
wakeup(&kg->kg_completed);
|
|
PROC_UNLOCK(p);
|
|
return (0);
|
|
}
|
|
ku = TAILQ_FIRST(&kg->kg_upcalls);
|
|
}
|
|
if (ku == NULL) {
|
|
mtx_unlock_spin(&sched_lock);
|
|
PROC_UNLOCK(p);
|
|
return (ESRCH);
|
|
}
|
|
if ((td2 = ku->ku_owner) == NULL) {
|
|
mtx_unlock_spin(&sched_lock);
|
|
panic("%s: no owner", __func__);
|
|
} else if (td2->td_kflags & (TDK_KSEREL | TDK_KSERELSIG)) {
|
|
mtx_unlock_spin(&sched_lock);
|
|
if (!(td2->td_kflags & TDK_WAKEUP)) {
|
|
td2->td_kflags |= TDK_WAKEUP;
|
|
if (td2->td_kflags & TDK_KSEREL)
|
|
sleepq_remove(td2, &kg->kg_completed);
|
|
else
|
|
sleepq_remove(td2, &p->p_siglist);
|
|
}
|
|
} else {
|
|
ku->ku_flags |= KUF_DOUPCALL;
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
PROC_UNLOCK(p);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* No new KSEG: first call: use current KSE, don't schedule an upcall
|
|
* All other situations, do allocate max new KSEs and schedule an upcall.
|
|
*
|
|
* XXX should be changed so that 'first' behaviour lasts for as long
|
|
* as you have not made a kse in this ksegrp. i.e. as long as we do not have
|
|
* a mailbox..
|
|
*/
|
|
/* struct kse_create_args {
|
|
struct kse_mailbox *mbx;
|
|
int newgroup;
|
|
}; */
|
|
int
|
|
kse_create(struct thread *td, struct kse_create_args *uap)
|
|
{
|
|
struct ksegrp *newkg;
|
|
struct ksegrp *kg;
|
|
struct proc *p;
|
|
struct kse_mailbox mbx;
|
|
struct kse_upcall *newku;
|
|
int err, ncpus, sa = 0, first = 0;
|
|
struct thread *newtd;
|
|
|
|
p = td->td_proc;
|
|
kg = td->td_ksegrp;
|
|
if ((err = copyin(uap->mbx, &mbx, sizeof(mbx))))
|
|
return (err);
|
|
|
|
ncpus = mp_ncpus;
|
|
if (virtual_cpu != 0)
|
|
ncpus = virtual_cpu;
|
|
/*
|
|
* If the new UTS mailbox says that this
|
|
* will be a BOUND lwp, then it had better
|
|
* have its thread mailbox already there.
|
|
* In addition, this ksegrp will be limited to
|
|
* a concurrency of 1. There is more on this later.
|
|
*/
|
|
if (mbx.km_flags & KMF_BOUND) {
|
|
if (mbx.km_curthread == NULL)
|
|
return (EINVAL);
|
|
ncpus = 1;
|
|
} else {
|
|
sa = TDP_SA;
|
|
}
|
|
|
|
PROC_LOCK(p);
|
|
/*
|
|
* Processes using the other threading model can't
|
|
* suddenly start calling this one
|
|
*/
|
|
if ((p->p_flag & (P_SA|P_HADTHREADS)) == P_HADTHREADS) {
|
|
PROC_UNLOCK(p);
|
|
return (EINVAL);
|
|
}
|
|
|
|
/*
|
|
* Limit it to NCPU upcall contexts per ksegrp in any case.
|
|
* There is a small race here as we don't hold proclock
|
|
* until we inc the ksegrp count, but it's not really a big problem
|
|
* if we get one too many, but we save a proc lock.
|
|
*/
|
|
if ((!uap->newgroup) && (kg->kg_numupcalls >= ncpus)) {
|
|
PROC_UNLOCK(p);
|
|
return (EPROCLIM);
|
|
}
|
|
|
|
if (!(p->p_flag & P_SA)) {
|
|
first = 1;
|
|
p->p_flag |= P_SA|P_HADTHREADS;
|
|
}
|
|
|
|
PROC_UNLOCK(p);
|
|
/*
|
|
* Now pay attention!
|
|
* If we are going to be bound, then we need to be either
|
|
* a new group, or the first call ever. In either
|
|
* case we will be creating (or be) the only thread in a group.
|
|
* and the concurrency will be set to 1.
|
|
* This is not quite right, as we may still make ourself
|
|
* bound after making other ksegrps but it will do for now.
|
|
* The library will only try do this much.
|
|
*/
|
|
if (!sa && !(uap->newgroup || first))
|
|
return (EINVAL);
|
|
|
|
if (uap->newgroup) {
|
|
newkg = ksegrp_alloc();
|
|
bzero(&newkg->kg_startzero,
|
|
__rangeof(struct ksegrp, kg_startzero, kg_endzero));
|
|
bcopy(&kg->kg_startcopy, &newkg->kg_startcopy,
|
|
__rangeof(struct ksegrp, kg_startcopy, kg_endcopy));
|
|
sched_init_concurrency(newkg);
|
|
PROC_LOCK(p);
|
|
if (p->p_numksegrps >= max_groups_per_proc) {
|
|
PROC_UNLOCK(p);
|
|
ksegrp_free(newkg);
|
|
return (EPROCLIM);
|
|
}
|
|
ksegrp_link(newkg, p);
|
|
mtx_lock_spin(&sched_lock);
|
|
sched_fork_ksegrp(td, newkg);
|
|
mtx_unlock_spin(&sched_lock);
|
|
PROC_UNLOCK(p);
|
|
} else {
|
|
/*
|
|
* We want to make a thread in our own ksegrp.
|
|
* If we are just the first call, either kind
|
|
* is ok, but if not then either we must be
|
|
* already an upcallable thread to make another,
|
|
* or a bound thread to make one of those.
|
|
* Once again, not quite right but good enough for now.. XXXKSE
|
|
*/
|
|
if (!first && ((td->td_pflags & TDP_SA) != sa))
|
|
return (EINVAL);
|
|
|
|
newkg = kg;
|
|
}
|
|
|
|
/*
|
|
* This test is a bit "indirect".
|
|
* It might simplify things if we made a direct way of testing
|
|
* if a ksegrp has been worked on before.
|
|
* In the case of a bound request and the concurrency being set to
|
|
* one, the concurrency will already be 1 so it's just inefficient
|
|
* but not dangerous to call this again. XXX
|
|
*/
|
|
if (newkg->kg_numupcalls == 0) {
|
|
/*
|
|
* Initialize KSE group with the appropriate
|
|
* concurrency.
|
|
*
|
|
* For a multiplexed group, create as as much concurrency
|
|
* as the number of physical cpus.
|
|
* This increases concurrency in the kernel even if the
|
|
* userland is not MP safe and can only run on a single CPU.
|
|
* In an ideal world, every physical cpu should execute a
|
|
* thread. If there is enough concurrency, threads in the
|
|
* kernel can be executed parallel on different cpus at
|
|
* full speed without being restricted by the number of
|
|
* upcalls the userland provides.
|
|
* Adding more upcall structures only increases concurrency
|
|
* in userland.
|
|
*
|
|
* For a bound thread group, because there is only one thread
|
|
* in the group, we only set the concurrency for the group
|
|
* to 1. A thread in this kind of group will never schedule
|
|
* an upcall when blocked. This simulates pthread system
|
|
* scope thread behaviour.
|
|
*/
|
|
sched_set_concurrency(newkg, ncpus);
|
|
}
|
|
/*
|
|
* Even bound LWPs get a mailbox and an upcall to hold it.
|
|
*/
|
|
newku = upcall_alloc();
|
|
newku->ku_mailbox = uap->mbx;
|
|
newku->ku_func = mbx.km_func;
|
|
bcopy(&mbx.km_stack, &newku->ku_stack, sizeof(stack_t));
|
|
|
|
/*
|
|
* For the first call this may not have been set.
|
|
* Of course nor may it actually be needed.
|
|
*/
|
|
if (td->td_standin == NULL)
|
|
thread_alloc_spare(td);
|
|
|
|
PROC_LOCK(p);
|
|
mtx_lock_spin(&sched_lock);
|
|
if (newkg->kg_numupcalls >= ncpus) {
|
|
mtx_unlock_spin(&sched_lock);
|
|
PROC_UNLOCK(p);
|
|
upcall_free(newku);
|
|
return (EPROCLIM);
|
|
}
|
|
|
|
/*
|
|
* If we are the first time, and a normal thread,
|
|
* then transfer all the signals back to the 'process'.
|
|
* SA threading will make a special thread to handle them.
|
|
*/
|
|
if (first && sa) {
|
|
SIGSETOR(p->p_siglist, td->td_siglist);
|
|
SIGEMPTYSET(td->td_siglist);
|
|
SIGFILLSET(td->td_sigmask);
|
|
SIG_CANTMASK(td->td_sigmask);
|
|
}
|
|
|
|
/*
|
|
* Make the new upcall available to the ksegrp.
|
|
* It may or may not use it, but it's available.
|
|
*/
|
|
PROC_UNLOCK(p);
|
|
upcall_link(newku, newkg);
|
|
if (mbx.km_quantum)
|
|
newkg->kg_upquantum = max(1, mbx.km_quantum / tick);
|
|
|
|
/*
|
|
* Each upcall structure has an owner thread, find which
|
|
* one owns it.
|
|
*/
|
|
if (uap->newgroup) {
|
|
/*
|
|
* Because the new ksegrp hasn't a thread,
|
|
* create an initial upcall thread to own it.
|
|
*/
|
|
newtd = thread_schedule_upcall(td, newku);
|
|
} else {
|
|
/*
|
|
* If the current thread hasn't an upcall structure,
|
|
* just assign the upcall to it.
|
|
* It'll just return.
|
|
*/
|
|
if (td->td_upcall == NULL) {
|
|
newku->ku_owner = td;
|
|
td->td_upcall = newku;
|
|
newtd = td;
|
|
} else {
|
|
/*
|
|
* Create a new upcall thread to own it.
|
|
*/
|
|
newtd = thread_schedule_upcall(td, newku);
|
|
}
|
|
}
|
|
mtx_unlock_spin(&sched_lock);
|
|
|
|
/*
|
|
* Let the UTS instance know its LWPID.
|
|
* It doesn't really care. But the debugger will.
|
|
*/
|
|
suword32(&newku->ku_mailbox->km_lwp, newtd->td_tid);
|
|
|
|
/*
|
|
* In the same manner, if the UTS has a current user thread,
|
|
* then it is also running on this LWP so set it as well.
|
|
* The library could do that of course.. but why not..
|
|
*/
|
|
if (mbx.km_curthread)
|
|
suword32(&mbx.km_curthread->tm_lwp, newtd->td_tid);
|
|
|
|
|
|
if (sa) {
|
|
newtd->td_pflags |= TDP_SA;
|
|
} else {
|
|
newtd->td_pflags &= ~TDP_SA;
|
|
|
|
/*
|
|
* Since a library will use the mailbox pointer to
|
|
* identify even a bound thread, and the mailbox pointer
|
|
* will never be allowed to change after this syscall
|
|
* for a bound thread, set it here so the library can
|
|
* find the thread after the syscall returns.
|
|
*/
|
|
newtd->td_mailbox = mbx.km_curthread;
|
|
|
|
if (newtd != td) {
|
|
/*
|
|
* If we did create a new thread then
|
|
* make sure it goes to the right place
|
|
* when it starts up, and make sure that it runs
|
|
* at full speed when it gets there.
|
|
* thread_schedule_upcall() copies all cpu state
|
|
* to the new thread, so we should clear single step
|
|
* flag here.
|
|
*/
|
|
cpu_set_upcall_kse(newtd, newku->ku_func,
|
|
newku->ku_mailbox, &newku->ku_stack);
|
|
if (p->p_flag & P_TRACED)
|
|
ptrace_clear_single_step(newtd);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we are starting a new thread, kick it off.
|
|
*/
|
|
if (newtd != td) {
|
|
mtx_lock_spin(&sched_lock);
|
|
setrunqueue(newtd, SRQ_BORING);
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Initialize global thread allocation resources.
|
|
*/
|
|
void
|
|
kseinit(void)
|
|
{
|
|
|
|
upcall_zone = uma_zcreate("UPCALL", sizeof(struct kse_upcall),
|
|
NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
|
|
}
|
|
|
|
/*
|
|
* Stash an embarasingly extra upcall into the zombie upcall queue.
|
|
*/
|
|
|
|
void
|
|
upcall_stash(struct kse_upcall *ku)
|
|
{
|
|
mtx_lock_spin(&kse_zombie_lock);
|
|
TAILQ_INSERT_HEAD(&zombie_upcalls, ku, ku_link);
|
|
mtx_unlock_spin(&kse_zombie_lock);
|
|
}
|
|
|
|
/*
|
|
* Reap zombie kse resource.
|
|
*/
|
|
void
|
|
kse_GC(void)
|
|
{
|
|
struct kse_upcall *ku_first, *ku_next;
|
|
|
|
/*
|
|
* Don't even bother to lock if none at this instant,
|
|
* we really don't care about the next instant..
|
|
*/
|
|
if (!TAILQ_EMPTY(&zombie_upcalls)) {
|
|
mtx_lock_spin(&kse_zombie_lock);
|
|
ku_first = TAILQ_FIRST(&zombie_upcalls);
|
|
if (ku_first)
|
|
TAILQ_INIT(&zombie_upcalls);
|
|
mtx_unlock_spin(&kse_zombie_lock);
|
|
while (ku_first) {
|
|
ku_next = TAILQ_NEXT(ku_first, ku_link);
|
|
upcall_free(ku_first);
|
|
ku_first = ku_next;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Store the thread context in the UTS's mailbox.
|
|
* then add the mailbox at the head of a list we are building in user space.
|
|
* The list is anchored in the ksegrp structure.
|
|
*/
|
|
int
|
|
thread_export_context(struct thread *td, int willexit)
|
|
{
|
|
struct proc *p;
|
|
struct ksegrp *kg;
|
|
uintptr_t mbx;
|
|
void *addr;
|
|
int error = 0, sig;
|
|
mcontext_t mc;
|
|
|
|
p = td->td_proc;
|
|
kg = td->td_ksegrp;
|
|
|
|
/*
|
|
* Post sync signal, or process SIGKILL and SIGSTOP.
|
|
* For sync signal, it is only possible when the signal is not
|
|
* caught by userland or process is being debugged.
|
|
*/
|
|
PROC_LOCK(p);
|
|
if (td->td_flags & TDF_NEEDSIGCHK) {
|
|
mtx_lock_spin(&sched_lock);
|
|
td->td_flags &= ~TDF_NEEDSIGCHK;
|
|
mtx_unlock_spin(&sched_lock);
|
|
mtx_lock(&p->p_sigacts->ps_mtx);
|
|
while ((sig = cursig(td)) != 0)
|
|
postsig(sig);
|
|
mtx_unlock(&p->p_sigacts->ps_mtx);
|
|
}
|
|
if (willexit)
|
|
SIGFILLSET(td->td_sigmask);
|
|
PROC_UNLOCK(p);
|
|
|
|
/* Export the user/machine context. */
|
|
get_mcontext(td, &mc, 0);
|
|
addr = (void *)(&td->td_mailbox->tm_context.uc_mcontext);
|
|
error = copyout(&mc, addr, sizeof(mcontext_t));
|
|
if (error)
|
|
goto bad;
|
|
|
|
addr = (caddr_t)(&td->td_mailbox->tm_lwp);
|
|
if (suword32(addr, 0)) {
|
|
error = EFAULT;
|
|
goto bad;
|
|
}
|
|
|
|
/* Get address in latest mbox of list pointer */
|
|
addr = (void *)(&td->td_mailbox->tm_next);
|
|
/*
|
|
* Put the saved address of the previous first
|
|
* entry into this one
|
|
*/
|
|
for (;;) {
|
|
mbx = (uintptr_t)kg->kg_completed;
|
|
if (suword(addr, mbx)) {
|
|
error = EFAULT;
|
|
goto bad;
|
|
}
|
|
PROC_LOCK(p);
|
|
if (mbx == (uintptr_t)kg->kg_completed) {
|
|
kg->kg_completed = td->td_mailbox;
|
|
/*
|
|
* The thread context may be taken away by
|
|
* other upcall threads when we unlock
|
|
* process lock. it's no longer valid to
|
|
* use it again in any other places.
|
|
*/
|
|
td->td_mailbox = NULL;
|
|
PROC_UNLOCK(p);
|
|
break;
|
|
}
|
|
PROC_UNLOCK(p);
|
|
}
|
|
td->td_usticks = 0;
|
|
return (0);
|
|
|
|
bad:
|
|
PROC_LOCK(p);
|
|
sigexit(td, SIGILL);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Take the list of completed mailboxes for this KSEGRP and put them on this
|
|
* upcall's mailbox as it's the next one going up.
|
|
*/
|
|
static int
|
|
thread_link_mboxes(struct ksegrp *kg, struct kse_upcall *ku)
|
|
{
|
|
struct proc *p = kg->kg_proc;
|
|
void *addr;
|
|
uintptr_t mbx;
|
|
|
|
addr = (void *)(&ku->ku_mailbox->km_completed);
|
|
for (;;) {
|
|
mbx = (uintptr_t)kg->kg_completed;
|
|
if (suword(addr, mbx)) {
|
|
PROC_LOCK(p);
|
|
psignal(p, SIGSEGV);
|
|
PROC_UNLOCK(p);
|
|
return (EFAULT);
|
|
}
|
|
PROC_LOCK(p);
|
|
if (mbx == (uintptr_t)kg->kg_completed) {
|
|
kg->kg_completed = NULL;
|
|
PROC_UNLOCK(p);
|
|
break;
|
|
}
|
|
PROC_UNLOCK(p);
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* This function should be called at statclock interrupt time
|
|
*/
|
|
int
|
|
thread_statclock(int user)
|
|
{
|
|
struct thread *td = curthread;
|
|
|
|
if (!(td->td_pflags & TDP_SA))
|
|
return (0);
|
|
if (user) {
|
|
/* Current always do via ast() */
|
|
mtx_lock_spin(&sched_lock);
|
|
td->td_flags |= TDF_ASTPENDING;
|
|
mtx_unlock_spin(&sched_lock);
|
|
td->td_uuticks++;
|
|
} else if (td->td_mailbox != NULL)
|
|
td->td_usticks++;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Export state clock ticks for userland
|
|
*/
|
|
static int
|
|
thread_update_usr_ticks(struct thread *td)
|
|
{
|
|
struct proc *p = td->td_proc;
|
|
caddr_t addr;
|
|
u_int uticks;
|
|
|
|
if (td->td_mailbox == NULL)
|
|
return (-1);
|
|
|
|
if ((uticks = td->td_uuticks) != 0) {
|
|
td->td_uuticks = 0;
|
|
addr = (caddr_t)&td->td_mailbox->tm_uticks;
|
|
if (suword32(addr, uticks+fuword32(addr)))
|
|
goto error;
|
|
}
|
|
if ((uticks = td->td_usticks) != 0) {
|
|
td->td_usticks = 0;
|
|
addr = (caddr_t)&td->td_mailbox->tm_sticks;
|
|
if (suword32(addr, uticks+fuword32(addr)))
|
|
goto error;
|
|
}
|
|
return (0);
|
|
|
|
error:
|
|
PROC_LOCK(p);
|
|
psignal(p, SIGSEGV);
|
|
PROC_UNLOCK(p);
|
|
return (-2);
|
|
}
|
|
|
|
/*
|
|
* This function is intended to be used to initialize a spare thread
|
|
* for upcall. Initialize thread's large data area outside sched_lock
|
|
* for thread_schedule_upcall(). The crhold is also here to get it out
|
|
* from the schedlock as it has a mutex op itself.
|
|
* XXX BUG.. we need to get the cr ref after the thread has
|
|
* checked and chenged its own, not 6 months before...
|
|
*/
|
|
void
|
|
thread_alloc_spare(struct thread *td)
|
|
{
|
|
struct thread *spare;
|
|
|
|
if (td->td_standin)
|
|
return;
|
|
spare = thread_alloc();
|
|
td->td_standin = spare;
|
|
bzero(&spare->td_startzero,
|
|
__rangeof(struct thread, td_startzero, td_endzero));
|
|
spare->td_proc = td->td_proc;
|
|
spare->td_ucred = crhold(td->td_ucred);
|
|
}
|
|
|
|
/*
|
|
* Create a thread and schedule it for upcall on the KSE given.
|
|
* Use our thread's standin so that we don't have to allocate one.
|
|
*/
|
|
struct thread *
|
|
thread_schedule_upcall(struct thread *td, struct kse_upcall *ku)
|
|
{
|
|
struct thread *td2;
|
|
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
|
|
/*
|
|
* Schedule an upcall thread on specified kse_upcall,
|
|
* the kse_upcall must be free.
|
|
* td must have a spare thread.
|
|
*/
|
|
KASSERT(ku->ku_owner == NULL, ("%s: upcall has owner", __func__));
|
|
if ((td2 = td->td_standin) != NULL) {
|
|
td->td_standin = NULL;
|
|
} else {
|
|
panic("no reserve thread when scheduling an upcall");
|
|
return (NULL);
|
|
}
|
|
CTR3(KTR_PROC, "thread_schedule_upcall: thread %p (pid %d, %s)",
|
|
td2, td->td_proc->p_pid, td->td_proc->p_comm);
|
|
/*
|
|
* Bzero already done in thread_alloc_spare() because we can't
|
|
* do the crhold here because we are in schedlock already.
|
|
*/
|
|
bcopy(&td->td_startcopy, &td2->td_startcopy,
|
|
__rangeof(struct thread, td_startcopy, td_endcopy));
|
|
thread_link(td2, ku->ku_ksegrp);
|
|
/* inherit parts of blocked thread's context as a good template */
|
|
cpu_set_upcall(td2, td);
|
|
/* Let the new thread become owner of the upcall */
|
|
ku->ku_owner = td2;
|
|
td2->td_upcall = ku;
|
|
td2->td_flags = 0;
|
|
td2->td_pflags = TDP_SA|TDP_UPCALLING;
|
|
td2->td_state = TDS_CAN_RUN;
|
|
td2->td_inhibitors = 0;
|
|
SIGFILLSET(td2->td_sigmask);
|
|
SIG_CANTMASK(td2->td_sigmask);
|
|
sched_fork_thread(td, td2);
|
|
return (td2); /* bogus.. should be a void function */
|
|
}
|
|
|
|
/*
|
|
* It is only used when thread generated a trap and process is being
|
|
* debugged.
|
|
*/
|
|
void
|
|
thread_signal_add(struct thread *td, int sig)
|
|
{
|
|
struct proc *p;
|
|
siginfo_t siginfo;
|
|
struct sigacts *ps;
|
|
int error;
|
|
|
|
p = td->td_proc;
|
|
PROC_LOCK_ASSERT(p, MA_OWNED);
|
|
ps = p->p_sigacts;
|
|
mtx_assert(&ps->ps_mtx, MA_OWNED);
|
|
|
|
cpu_thread_siginfo(sig, 0, &siginfo);
|
|
mtx_unlock(&ps->ps_mtx);
|
|
SIGADDSET(td->td_sigmask, sig);
|
|
PROC_UNLOCK(p);
|
|
error = copyout(&siginfo, &td->td_mailbox->tm_syncsig, sizeof(siginfo));
|
|
if (error) {
|
|
PROC_LOCK(p);
|
|
sigexit(td, SIGSEGV);
|
|
}
|
|
PROC_LOCK(p);
|
|
mtx_lock(&ps->ps_mtx);
|
|
}
|
|
#include "opt_sched.h"
|
|
struct thread *
|
|
thread_switchout(struct thread *td, int flags, struct thread *nextthread)
|
|
{
|
|
struct kse_upcall *ku;
|
|
struct thread *td2;
|
|
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
|
|
/*
|
|
* If the outgoing thread is in threaded group and has never
|
|
* scheduled an upcall, decide whether this is a short
|
|
* or long term event and thus whether or not to schedule
|
|
* an upcall.
|
|
* If it is a short term event, just suspend it in
|
|
* a way that takes its KSE with it.
|
|
* Select the events for which we want to schedule upcalls.
|
|
* For now it's just sleep or if thread is suspended but
|
|
* process wide suspending flag is not set (debugger
|
|
* suspends thread).
|
|
* XXXKSE eventually almost any inhibition could do.
|
|
*/
|
|
if (TD_CAN_UNBIND(td) && (td->td_standin) &&
|
|
(TD_ON_SLEEPQ(td) || (TD_IS_SUSPENDED(td) &&
|
|
!P_SHOULDSTOP(td->td_proc)))) {
|
|
/*
|
|
* Release ownership of upcall, and schedule an upcall
|
|
* thread, this new upcall thread becomes the owner of
|
|
* the upcall structure. It will be ahead of us in the
|
|
* run queue, so as we are stopping, it should either
|
|
* start up immediatly, or at least before us if
|
|
* we release our slot.
|
|
*/
|
|
ku = td->td_upcall;
|
|
ku->ku_owner = NULL;
|
|
td->td_upcall = NULL;
|
|
td->td_pflags &= ~TDP_CAN_UNBIND;
|
|
td2 = thread_schedule_upcall(td, ku);
|
|
if (flags & SW_INVOL || nextthread) {
|
|
setrunqueue(td2, SRQ_YIELDING);
|
|
} else {
|
|
/* Keep up with reality.. we have one extra thread
|
|
* in the picture.. and it's 'running'.
|
|
*/
|
|
return td2;
|
|
}
|
|
}
|
|
return (nextthread);
|
|
}
|
|
|
|
/*
|
|
* Setup done on the thread when it enters the kernel.
|
|
*/
|
|
void
|
|
thread_user_enter(struct thread *td)
|
|
{
|
|
struct proc *p = td->td_proc;
|
|
struct ksegrp *kg;
|
|
struct kse_upcall *ku;
|
|
struct kse_thr_mailbox *tmbx;
|
|
uint32_t flags;
|
|
|
|
/*
|
|
* First check that we shouldn't just abort. we
|
|
* can suspend it here or just exit.
|
|
*/
|
|
if (__predict_false(P_SHOULDSTOP(p))) {
|
|
PROC_LOCK(p);
|
|
thread_suspend_check(0);
|
|
PROC_UNLOCK(p);
|
|
}
|
|
|
|
if (!(td->td_pflags & TDP_SA))
|
|
return;
|
|
|
|
/*
|
|
* If we are doing a syscall in a KSE environment,
|
|
* note where our mailbox is.
|
|
*/
|
|
|
|
kg = td->td_ksegrp;
|
|
ku = td->td_upcall;
|
|
|
|
KASSERT(ku != NULL, ("no upcall owned"));
|
|
KASSERT(ku->ku_owner == td, ("wrong owner"));
|
|
KASSERT(!TD_CAN_UNBIND(td), ("can unbind"));
|
|
|
|
if (td->td_standin == NULL)
|
|
thread_alloc_spare(td);
|
|
ku->ku_mflags = fuword32((void *)&ku->ku_mailbox->km_flags);
|
|
tmbx = (void *)fuword((void *)&ku->ku_mailbox->km_curthread);
|
|
if ((tmbx == NULL) || (tmbx == (void *)-1L) ||
|
|
(ku->ku_mflags & KMF_NOUPCALL)) {
|
|
td->td_mailbox = NULL;
|
|
} else {
|
|
flags = fuword32(&tmbx->tm_flags);
|
|
/*
|
|
* On some architectures, TP register points to thread
|
|
* mailbox but not points to kse mailbox, and userland
|
|
* can not atomically clear km_curthread, but can
|
|
* use TP register, and set TMF_NOUPCALL in thread
|
|
* flag to indicate a critical region.
|
|
*/
|
|
if (flags & TMF_NOUPCALL) {
|
|
td->td_mailbox = NULL;
|
|
} else {
|
|
td->td_mailbox = tmbx;
|
|
td->td_pflags |= TDP_CAN_UNBIND;
|
|
if (__predict_false(p->p_flag & P_TRACED)) {
|
|
flags = fuword32(&tmbx->tm_dflags);
|
|
if (flags & TMDF_SUSPEND) {
|
|
mtx_lock_spin(&sched_lock);
|
|
/* fuword can block, check again */
|
|
if (td->td_upcall)
|
|
ku->ku_flags |= KUF_DOUPCALL;
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* The extra work we go through if we are a threaded process when we
|
|
* return to userland.
|
|
*
|
|
* If we are a KSE process and returning to user mode, check for
|
|
* extra work to do before we return (e.g. for more syscalls
|
|
* to complete first). If we were in a critical section, we should
|
|
* just return to let it finish. Same if we were in the UTS (in
|
|
* which case the mailbox's context's busy indicator will be set).
|
|
* The only traps we suport will have set the mailbox.
|
|
* We will clear it here.
|
|
*/
|
|
int
|
|
thread_userret(struct thread *td, struct trapframe *frame)
|
|
{
|
|
struct kse_upcall *ku;
|
|
struct ksegrp *kg, *kg2;
|
|
struct proc *p;
|
|
struct timespec ts;
|
|
int error = 0, upcalls, uts_crit;
|
|
|
|
/* Nothing to do with bound thread */
|
|
if (!(td->td_pflags & TDP_SA))
|
|
return (0);
|
|
|
|
/*
|
|
* Update stat clock count for userland
|
|
*/
|
|
if (td->td_mailbox != NULL) {
|
|
thread_update_usr_ticks(td);
|
|
uts_crit = 0;
|
|
} else {
|
|
uts_crit = 1;
|
|
}
|
|
|
|
p = td->td_proc;
|
|
kg = td->td_ksegrp;
|
|
ku = td->td_upcall;
|
|
|
|
/*
|
|
* Optimisation:
|
|
* This thread has not started any upcall.
|
|
* If there is no work to report other than ourself,
|
|
* then it can return direct to userland.
|
|
*/
|
|
if (TD_CAN_UNBIND(td)) {
|
|
td->td_pflags &= ~TDP_CAN_UNBIND;
|
|
if ((td->td_flags & TDF_NEEDSIGCHK) == 0 &&
|
|
(kg->kg_completed == NULL) &&
|
|
(ku->ku_flags & KUF_DOUPCALL) == 0 &&
|
|
(kg->kg_upquantum && ticks < kg->kg_nextupcall)) {
|
|
nanotime(&ts);
|
|
error = copyout(&ts,
|
|
(caddr_t)&ku->ku_mailbox->km_timeofday,
|
|
sizeof(ts));
|
|
td->td_mailbox = 0;
|
|
ku->ku_mflags = 0;
|
|
if (error)
|
|
goto out;
|
|
return (0);
|
|
}
|
|
thread_export_context(td, 0);
|
|
/*
|
|
* There is something to report, and we own an upcall
|
|
* strucuture, we can go to userland.
|
|
* Turn ourself into an upcall thread.
|
|
*/
|
|
td->td_pflags |= TDP_UPCALLING;
|
|
} else if (td->td_mailbox && (ku == NULL)) {
|
|
thread_export_context(td, 1);
|
|
PROC_LOCK(p);
|
|
if (kg->kg_upsleeps)
|
|
wakeup(&kg->kg_completed);
|
|
mtx_lock_spin(&sched_lock);
|
|
thread_stopped(p);
|
|
thread_exit();
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
KASSERT(ku != NULL, ("upcall is NULL"));
|
|
KASSERT(TD_CAN_UNBIND(td) == 0, ("can unbind"));
|
|
|
|
if (p->p_numthreads > max_threads_per_proc) {
|
|
max_threads_hits++;
|
|
PROC_LOCK(p);
|
|
mtx_lock_spin(&sched_lock);
|
|
p->p_maxthrwaits++;
|
|
while (p->p_numthreads > max_threads_per_proc) {
|
|
upcalls = 0;
|
|
FOREACH_KSEGRP_IN_PROC(p, kg2) {
|
|
if (kg2->kg_numupcalls == 0)
|
|
upcalls++;
|
|
else
|
|
upcalls += kg2->kg_numupcalls;
|
|
}
|
|
if (upcalls >= max_threads_per_proc)
|
|
break;
|
|
mtx_unlock_spin(&sched_lock);
|
|
if (msleep(&p->p_numthreads, &p->p_mtx, PPAUSE|PCATCH,
|
|
"maxthreads", 0)) {
|
|
mtx_lock_spin(&sched_lock);
|
|
break;
|
|
} else {
|
|
mtx_lock_spin(&sched_lock);
|
|
}
|
|
}
|
|
p->p_maxthrwaits--;
|
|
mtx_unlock_spin(&sched_lock);
|
|
PROC_UNLOCK(p);
|
|
}
|
|
|
|
if (td->td_pflags & TDP_UPCALLING) {
|
|
uts_crit = 0;
|
|
kg->kg_nextupcall = ticks + kg->kg_upquantum;
|
|
/*
|
|
* There is no more work to do and we are going to ride
|
|
* this thread up to userland as an upcall.
|
|
* Do the last parts of the setup needed for the upcall.
|
|
*/
|
|
CTR3(KTR_PROC, "userret: upcall thread %p (pid %d, %s)",
|
|
td, td->td_proc->p_pid, td->td_proc->p_comm);
|
|
|
|
td->td_pflags &= ~TDP_UPCALLING;
|
|
if (ku->ku_flags & KUF_DOUPCALL) {
|
|
mtx_lock_spin(&sched_lock);
|
|
ku->ku_flags &= ~KUF_DOUPCALL;
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
/*
|
|
* Set user context to the UTS
|
|
*/
|
|
if (!(ku->ku_mflags & KMF_NOUPCALL)) {
|
|
cpu_set_upcall_kse(td, ku->ku_func, ku->ku_mailbox,
|
|
&ku->ku_stack);
|
|
if (p->p_flag & P_TRACED)
|
|
ptrace_clear_single_step(td);
|
|
error = suword32(&ku->ku_mailbox->km_lwp,
|
|
td->td_tid);
|
|
if (error)
|
|
goto out;
|
|
error = suword(&ku->ku_mailbox->km_curthread, 0);
|
|
if (error)
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Unhook the list of completed threads.
|
|
* anything that completes after this gets to
|
|
* come in next time.
|
|
* Put the list of completed thread mailboxes on
|
|
* this KSE's mailbox.
|
|
*/
|
|
if (!(ku->ku_mflags & KMF_NOCOMPLETED) &&
|
|
(error = thread_link_mboxes(kg, ku)) != 0)
|
|
goto out;
|
|
}
|
|
if (!uts_crit) {
|
|
nanotime(&ts);
|
|
error = copyout(&ts, &ku->ku_mailbox->km_timeofday, sizeof(ts));
|
|
}
|
|
|
|
out:
|
|
if (error) {
|
|
/*
|
|
* Things are going to be so screwed we should just kill
|
|
* the process.
|
|
* how do we do that?
|
|
*/
|
|
PROC_LOCK(p);
|
|
psignal(p, SIGSEGV);
|
|
PROC_UNLOCK(p);
|
|
} else {
|
|
/*
|
|
* Optimisation:
|
|
* Ensure that we have a spare thread available,
|
|
* for when we re-enter the kernel.
|
|
*/
|
|
if (td->td_standin == NULL)
|
|
thread_alloc_spare(td);
|
|
}
|
|
|
|
ku->ku_mflags = 0;
|
|
td->td_mailbox = NULL;
|
|
td->td_usticks = 0;
|
|
return (error); /* go sync */
|
|
}
|
|
|
|
int
|
|
thread_upcall_check(struct thread *td)
|
|
{
|
|
PROC_LOCK_ASSERT(td->td_proc, MA_OWNED);
|
|
if (td->td_kflags & TDK_WAKEUP)
|
|
return (1);
|
|
else
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* called after ptrace resumed a process, force all
|
|
* virtual CPUs to schedule upcall for SA process,
|
|
* because debugger may have changed something in userland,
|
|
* we should notice UTS as soon as possible.
|
|
*/
|
|
void
|
|
thread_continued(struct proc *p)
|
|
{
|
|
struct ksegrp *kg;
|
|
struct kse_upcall *ku;
|
|
struct thread *td;
|
|
|
|
PROC_LOCK_ASSERT(p, MA_OWNED);
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
|
|
if (!(p->p_flag & P_SA))
|
|
return;
|
|
|
|
if (p->p_flag & P_TRACED) {
|
|
FOREACH_KSEGRP_IN_PROC(p, kg) {
|
|
td = TAILQ_FIRST(&kg->kg_threads);
|
|
if (td == NULL)
|
|
continue;
|
|
/* not a SA group, nothing to do */
|
|
if (!(td->td_pflags & TDP_SA))
|
|
continue;
|
|
FOREACH_UPCALL_IN_GROUP(kg, ku) {
|
|
ku->ku_flags |= KUF_DOUPCALL;
|
|
wakeup(&kg->kg_completed);
|
|
if (TD_IS_SUSPENDED(ku->ku_owner)) {
|
|
thread_unsuspend_one(ku->ku_owner);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|