856 lines
23 KiB
C
856 lines
23 KiB
C
/*
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* Copyright (c) 2001 Jake Burkholder <jake@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, 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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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* $FreeBSD$
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*/
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/***
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Here is the logic..
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If there are N processors, then there are at most N KSEs (kernel
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schedulable entities) working to process threads that belong to a
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KSEGOUP (kg). If there are X of these KSEs actually running at the
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moment in question, then there are at most M (N-X) of these KSEs on
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the run queue, as running KSEs are not on the queue.
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Runnable threads are queued off the KSEGROUP in priority order.
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If there are M or more threads runnable, the top M threads
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(by priority) are 'preassigned' to the M KSEs not running. The KSEs take
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their priority from those threads and are put on the run queue.
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The last thread that had a priority high enough to have a KSE associated
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with it, AND IS ON THE RUN QUEUE is pointed to by
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kg->kg_last_assigned. If no threads queued off the KSEGROUP have KSEs
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assigned as all the available KSEs are activly running, or because there
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are no threads queued, that pointer is NULL.
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When a KSE is removed from the run queue to become runnable, we know
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it was associated with the highest priority thread in the queue (at the head
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of the queue). If it is also the last assigned we know M was 1 and must
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now be 0. Since the thread is no longer queued that pointer must be
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removed from it. Since we know there were no more KSEs available,
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(M was 1 and is now 0) and since we are not FREEING our KSE
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but using it, we know there are STILL no more KSEs available, we can prove
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that the next thread in the ksegrp list will not have a KSE to assign to
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it, so we can show that the pointer must be made 'invalid' (NULL).
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The pointer exists so that when a new thread is made runnable, it can
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have its priority compared with the last assigned thread to see if
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it should 'steal' its KSE or not.. i.e. is it 'earlier'
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on the list than that thread or later.. If it's earlier, then the KSE is
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removed from the last assigned (which is now not assigned a KSE)
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and reassigned to the new thread, which is placed earlier in the list.
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The pointer is then backed up to the previous thread (which may or may not
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be the new thread).
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When a thread sleeps or is removed, the KSE becomes available and if there
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are queued threads that are not assigned KSEs, the highest priority one of
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them is assigned the KSE, which is then placed back on the run queue at
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the approipriate place, and the kg->kg_last_assigned pointer is adjusted down
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to point to it.
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The following diagram shows 2 KSEs and 3 threads from a single process.
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RUNQ: --->KSE---KSE--... (KSEs queued at priorities from threads)
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\ \____
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\ \
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KSEGROUP---thread--thread--thread (queued in priority order)
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\ /
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\_______________/
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(last_assigned)
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The result of this scheme is that the M available KSEs are always
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queued at the priorities they have inherrited from the M highest priority
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threads for that KSEGROUP. If this situation changes, the KSEs are
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reassigned to keep this true.
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*/
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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/ktr.h>
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#include <sys/lock.h>
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#include <sys/mutex.h>
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#include <sys/proc.h>
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#include <sys/queue.h>
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#include <sys/sched.h>
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#include <machine/critical.h>
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CTASSERT((RQB_BPW * RQB_LEN) == RQ_NQS);
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void panc(char *string1, char *string2);
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#if 0
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static void runq_readjust(struct runq *rq, struct kse *ke);
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#endif
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/************************************************************************
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* Functions that manipulate runnability from a thread perspective. *
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************************************************************************/
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/*
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* Select the KSE that will be run next. From that find the thread, and x
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* remove it from the KSEGRP's run queue. If there is thread clustering,
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* this will be what does it.
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*/
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struct thread *
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choosethread(void)
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{
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struct kse *ke;
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struct thread *td;
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struct ksegrp *kg;
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retry:
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if ((ke = sched_choose())) {
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td = ke->ke_thread;
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KASSERT((td->td_kse == ke), ("kse/thread mismatch"));
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kg = ke->ke_ksegrp;
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if (TD_IS_UNBOUND(td)) {
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TAILQ_REMOVE(&kg->kg_runq, td, td_runq);
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if (kg->kg_last_assigned == td) {
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kg->kg_last_assigned = TAILQ_PREV(td,
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threadqueue, td_runq);
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}
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}
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kg->kg_runnable--;
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CTR2(KTR_RUNQ, "choosethread: td=%p pri=%d",
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td, td->td_priority);
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} else {
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/* Simulate runq_choose() having returned the idle thread */
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td = PCPU_GET(idlethread);
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ke = td->td_kse;
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CTR1(KTR_RUNQ, "choosethread: td=%p (idle)", td);
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}
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ke->ke_flags |= KEF_DIDRUN;
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/*
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* Only allow non system threads to run in panic
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* if they are the one we are tracing. (I think.. [JRE])
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*/
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if (panicstr && ((td->td_proc->p_flag & P_SYSTEM) == 0 &&
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(td->td_flags & TDF_INPANIC) == 0))
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goto retry;
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TD_SET_RUNNING(td);
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return (td);
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}
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/*
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* Given a KSE (now surplus or at least loanable), either assign a new
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* runable thread to it (and put it in the run queue) or put it in
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* the ksegrp's idle KSE list.
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* Or maybe give it back to its owner if it's been loaned.
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* Assumes that the original thread is either not runnable or
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* already on the run queue
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*/
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void
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kse_reassign(struct kse *ke)
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{
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struct ksegrp *kg;
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struct thread *td;
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struct thread *owner;
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struct thread *original;
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int loaned;
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KASSERT((ke->ke_owner), ("reassigning KSE with no owner"));
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KASSERT((ke->ke_thread && TD_IS_INHIBITED(ke->ke_thread)),
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("reassigning KSE with no or runnable thread"));
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mtx_assert(&sched_lock, MA_OWNED);
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kg = ke->ke_ksegrp;
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owner = ke->ke_owner;
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loaned = TD_LENDER(owner);
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original = ke->ke_thread;
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if (TD_CAN_UNBIND(original) && (original->td_standin)) {
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KASSERT((owner == original),
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("Early thread borrowing?"));
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/*
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* The outgoing thread is "threaded" and has never
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* scheduled an upcall.
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* decide whether this is a short or long term event
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* and thus whether or not to schedule an upcall.
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* if it is a short term event, just suspend it in
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* a way that takes its KSE with it.
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* Select the events for which we want to schedule upcalls.
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* For now it's just sleep.
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* Other threads that still have not fired an upcall
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* are held to their KSE using the temorary Binding.
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*/
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if (TD_ON_SLEEPQ(original)) {
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/*
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* An bound thread that can still unbind itself
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* has been scheduled out.
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* If it is sleeping, then we need to schedule an
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* upcall.
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* XXXKSE eventually almost any inhibition could do.
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*/
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original->td_flags &= ~TDF_CAN_UNBIND;
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original->td_flags |= TDF_UNBOUND;
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thread_schedule_upcall(original, ke);
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owner = ke->ke_owner;
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loaned = 1;
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}
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}
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/*
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* If the current thread was borrowing, then make things consistent
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* by giving it back to the owner for the moment. The original thread
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* must be unbound and have already used its chance for
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* firing off an upcall. Threads that have not yet made an upcall
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* can not borrow KSEs.
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*/
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if (loaned) {
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TD_CLR_LOAN(owner);
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ke->ke_thread = owner;
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original->td_kse = NULL; /* give it amnesia */
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/*
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* Upcalling threads have lower priority than all
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* in-kernel threads, However threads that have loaned out
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* their KSE and are NOT upcalling have the priority that
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* they have. In other words, only look for other work if
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* the owner is not runnable, OR is upcalling.
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*/
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if (TD_CAN_RUN(owner) &&
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((owner->td_flags & TDF_UPCALLING) == 0)) {
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setrunnable(owner);
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CTR2(KTR_RUNQ, "kse_reassign: ke%p -> td%p (give back)",
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ke, owner);
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return;
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}
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}
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/*
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* Either the owner is not runnable, or is an upcall.
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* Find the first unassigned thread
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* If there is a 'last assigned' then see what's next.
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* otherwise look at what is first.
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*/
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if ((td = kg->kg_last_assigned)) {
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td = TAILQ_NEXT(td, td_runq);
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} else {
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td = TAILQ_FIRST(&kg->kg_runq);
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}
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/*
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* If we found one assign it the kse, otherwise idle the kse.
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*/
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if (td) {
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/*
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* Assign the new thread to the KSE.
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* and make the KSE runnable again,
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*/
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if (TD_IS_BOUND(owner)) {
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/*
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* If there is a reason to keep the previous
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* owner, do so.
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*/
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TD_SET_LOAN(owner);
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} else {
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/* otherwise, cut it free */
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ke->ke_owner = td;
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owner->td_kse = NULL;
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}
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kg->kg_last_assigned = td;
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td->td_kse = ke;
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ke->ke_thread = td;
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sched_add(ke);
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CTR2(KTR_RUNQ, "kse_reassign: ke%p -> td%p", ke, td);
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return;
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}
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/*
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* Now handle any waiting upcall.
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* Since we didn't make them runnable before.
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*/
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if (TD_CAN_RUN(owner)) {
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setrunnable(owner);
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CTR2(KTR_RUNQ, "kse_reassign: ke%p -> td%p (give back)",
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ke, owner);
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return;
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}
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/*
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* It is possible that this is the last thread in the group
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* because the KSE is being shut down or the process
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* is exiting.
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*/
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if (TD_IS_EXITING(owner) || (ke->ke_flags & KEF_EXIT)) {
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ke->ke_thread = NULL;
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owner->td_kse = NULL;
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kse_unlink(ke);
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return;
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}
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/*
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* At this stage all we know is that the owner
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* is the same as the 'active' thread in the KSE
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* and that it is
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* Presently NOT loaned out.
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* Put it on the loanable queue. Make it fifo
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* so that long term sleepers donate their KSE's first.
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*/
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KASSERT((TD_IS_BOUND(owner)), ("kse_reassign: UNBOUND lender"));
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ke->ke_state = KES_THREAD;
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ke->ke_flags |= KEF_ONLOANQ;
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TAILQ_INSERT_TAIL(&kg->kg_lq, ke, ke_kgrlist);
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kg->kg_loan_kses++;
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CTR1(KTR_RUNQ, "kse_reassign: ke%p on loan queue", ke);
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return;
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}
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#if 0
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/*
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* Remove a thread from its KSEGRP's run queue.
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* This in turn may remove it from a KSE if it was already assigned
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* to one, possibly causing a new thread to be assigned to the KSE
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* and the KSE getting a new priority (unless it's a BOUND thread/KSE pair).
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*/
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static void
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remrunqueue(struct thread *td)
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{
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struct thread *td2, *td3;
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struct ksegrp *kg;
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struct kse *ke;
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mtx_assert(&sched_lock, MA_OWNED);
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KASSERT ((TD_ON_RUNQ(td)), ("remrunqueue: Bad state on run queue"));
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kg = td->td_ksegrp;
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ke = td->td_kse;
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/*
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* If it's a bound thread/KSE pair, take the shortcut. All non-KSE
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* threads are BOUND.
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*/
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CTR1(KTR_RUNQ, "remrunqueue: td%p", td);
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kg->kg_runnable--;
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TD_SET_CAN_RUN(td);
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if (TD_IS_BOUND(td)) {
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/* Bring its kse with it, leave the thread attached */
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sched_rem(ke);
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ke->ke_state = KES_THREAD;
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return;
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}
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td3 = TAILQ_PREV(td, threadqueue, td_runq);
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TAILQ_REMOVE(&kg->kg_runq, td, td_runq);
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if (ke) {
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/*
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* This thread has been assigned to a KSE.
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* We need to dissociate it and try assign the
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* KSE to the next available thread. Then, we should
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* see if we need to move the KSE in the run queues.
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*/
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sched_rem(ke);
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ke->ke_state = KES_THREAD;
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td2 = kg->kg_last_assigned;
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KASSERT((td2 != NULL), ("last assigned has wrong value "));
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if (td2 == td)
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kg->kg_last_assigned = td3;
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kse_reassign(ke);
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}
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}
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#endif
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/*
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* Change the priority of a thread that is on the run queue.
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*/
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void
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adjustrunqueue( struct thread *td, int newpri)
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{
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struct ksegrp *kg;
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struct kse *ke;
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mtx_assert(&sched_lock, MA_OWNED);
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KASSERT ((TD_ON_RUNQ(td)), ("adjustrunqueue: Bad state on run queue"));
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/*
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* If it's a bound thread/KSE pair, take the shortcut. All non-KSE
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* threads are BOUND.
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*/
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ke = td->td_kse;
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CTR1(KTR_RUNQ, "adjustrunqueue: td%p", td);
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if (TD_IS_BOUND(td)) {
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/* We only care about the kse in the run queue. */
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td->td_priority = newpri;
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if (ke->ke_rqindex != (newpri / RQ_PPQ)) {
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sched_rem(ke);
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sched_add(ke);
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}
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return;
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}
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/*
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* An unbound thread. This is not optimised yet.
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*/
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kg = td->td_ksegrp;
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kg->kg_runnable--;
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TD_SET_CAN_RUN(td);
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if (ke) {
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if (kg->kg_last_assigned == td) {
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kg->kg_last_assigned =
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TAILQ_PREV(td, threadqueue, td_runq);
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}
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sched_rem(ke);
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}
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TAILQ_REMOVE(&kg->kg_runq, td, td_runq);
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td->td_priority = newpri;
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setrunqueue(td);
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}
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void
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setrunqueue(struct thread *td)
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{
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struct kse *ke;
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struct ksegrp *kg;
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struct thread *td2;
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struct thread *tda;
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CTR1(KTR_RUNQ, "setrunqueue: td%p", td);
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mtx_assert(&sched_lock, MA_OWNED);
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KASSERT((TD_CAN_RUN(td) || TD_IS_RUNNING(td)),
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("setrunqueue: bad thread state"));
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TD_SET_RUNQ(td);
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kg = td->td_ksegrp;
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kg->kg_runnable++;
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if ((td->td_proc->p_flag & P_KSES) == 0) {
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/*
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* Common path optimisation: Only one of everything
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* and the KSE is always already attached.
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* Totally ignore the ksegrp run queue.
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*/
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sched_add(td->td_kse);
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return;
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}
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/*
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* If the process is threaded but the thread is bound then
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* there is still a little extra to do re. KSE loaning.
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*/
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if (TD_IS_BOUND(td)) {
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KASSERT((td->td_kse != NULL),
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("queueing BAD thread to run queue"));
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ke = td->td_kse;
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KASSERT((ke->ke_owner == ke->ke_thread),
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("setrunqueue: Hey KSE loaned out"));
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if (ke->ke_flags & KEF_ONLOANQ) {
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ke->ke_flags &= ~KEF_ONLOANQ;
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TAILQ_REMOVE(&kg->kg_lq, ke, ke_kgrlist);
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kg->kg_loan_kses--;
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}
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sched_add(td->td_kse);
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return;
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}
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/*
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* Ok, so we are threading with this thread.
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* We don't have a KSE, see if we can get one..
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*/
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tda = kg->kg_last_assigned;
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if ((ke = td->td_kse) == NULL) {
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/*
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* We will need a KSE, see if there is one..
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* First look for a free one, before getting desperate.
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* If we can't get one, our priority is not high enough..
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* that's ok..
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*/
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if (kg->kg_loan_kses) {
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/*
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* Failing that see if we can borrow one.
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*/
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ke = TAILQ_FIRST(&kg->kg_lq);
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TAILQ_REMOVE(&kg->kg_lq, ke, ke_kgrlist);
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ke->ke_flags &= ~KEF_ONLOANQ;
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ke->ke_state = KES_THREAD;
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TD_SET_LOAN(ke->ke_owner);
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ke->ke_thread = NULL;
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kg->kg_loan_kses--;
|
|
} else if (tda && (tda->td_priority > td->td_priority)) {
|
|
/*
|
|
* None free, but there is one we can commandeer.
|
|
*/
|
|
ke = tda->td_kse;
|
|
tda->td_kse = NULL;
|
|
ke->ke_thread = NULL;
|
|
tda = kg->kg_last_assigned =
|
|
TAILQ_PREV(tda, threadqueue, td_runq);
|
|
sched_rem(ke);
|
|
}
|
|
} else {
|
|
/*
|
|
* Temporarily disassociate so it looks like the other cases.
|
|
* If the owner wasn't lending before, then it is now..
|
|
*/
|
|
if (!TD_LENDER(ke->ke_owner)) {
|
|
TD_SET_LOAN(ke->ke_owner);
|
|
}
|
|
ke->ke_thread = NULL;
|
|
td->td_kse = NULL;
|
|
}
|
|
|
|
/*
|
|
* Add the thread to the ksegrp's run queue at
|
|
* the appropriate place.
|
|
*/
|
|
TAILQ_FOREACH(td2, &kg->kg_runq, td_runq) {
|
|
if (td2->td_priority > td->td_priority) {
|
|
TAILQ_INSERT_BEFORE(td2, td, td_runq);
|
|
break;
|
|
}
|
|
}
|
|
if (td2 == NULL) {
|
|
/* We ran off the end of the TAILQ or it was empty. */
|
|
TAILQ_INSERT_TAIL(&kg->kg_runq, td, td_runq);
|
|
}
|
|
|
|
/*
|
|
* If we have a ke to use, then put it on the run queue and
|
|
* If needed, readjust the last_assigned pointer.
|
|
*/
|
|
if (ke) {
|
|
if (tda == NULL) {
|
|
/*
|
|
* No pre-existing last assigned so whoever is first
|
|
* gets the KSE we brought in.. (maybe us)
|
|
*/
|
|
td2 = TAILQ_FIRST(&kg->kg_runq);
|
|
KASSERT((td2->td_kse == NULL),
|
|
("unexpected ke present"));
|
|
td2->td_kse = ke;
|
|
ke->ke_thread = td2;
|
|
kg->kg_last_assigned = td2;
|
|
} else if (tda->td_priority > td->td_priority) {
|
|
/*
|
|
* It's ours, grab it, but last_assigned is past us
|
|
* so don't change it.
|
|
*/
|
|
td->td_kse = ke;
|
|
ke->ke_thread = td;
|
|
} else {
|
|
/*
|
|
* We are past last_assigned, so
|
|
* put the new kse on whatever is next,
|
|
* which may or may not be us.
|
|
*/
|
|
td2 = TAILQ_NEXT(tda, td_runq);
|
|
kg->kg_last_assigned = td2;
|
|
td2->td_kse = ke;
|
|
ke->ke_thread = td2;
|
|
}
|
|
sched_add(ke);
|
|
}
|
|
}
|
|
|
|
/************************************************************************
|
|
* Critical section marker functions *
|
|
************************************************************************/
|
|
/* Critical sections that prevent preemption. */
|
|
void
|
|
critical_enter(void)
|
|
{
|
|
struct thread *td;
|
|
|
|
td = curthread;
|
|
if (td->td_critnest == 0)
|
|
cpu_critical_enter();
|
|
td->td_critnest++;
|
|
}
|
|
|
|
void
|
|
critical_exit(void)
|
|
{
|
|
struct thread *td;
|
|
|
|
td = curthread;
|
|
if (td->td_critnest == 1) {
|
|
td->td_critnest = 0;
|
|
cpu_critical_exit();
|
|
} else {
|
|
td->td_critnest--;
|
|
}
|
|
}
|
|
|
|
|
|
/************************************************************************
|
|
* SYSTEM RUN QUEUE manipulations and tests *
|
|
************************************************************************/
|
|
/*
|
|
* Initialize a run structure.
|
|
*/
|
|
void
|
|
runq_init(struct runq *rq)
|
|
{
|
|
int i;
|
|
|
|
bzero(rq, sizeof *rq);
|
|
for (i = 0; i < RQ_NQS; i++)
|
|
TAILQ_INIT(&rq->rq_queues[i]);
|
|
}
|
|
|
|
/*
|
|
* Clear the status bit of the queue corresponding to priority level pri,
|
|
* indicating that it is empty.
|
|
*/
|
|
static __inline void
|
|
runq_clrbit(struct runq *rq, int pri)
|
|
{
|
|
struct rqbits *rqb;
|
|
|
|
rqb = &rq->rq_status;
|
|
CTR4(KTR_RUNQ, "runq_clrbit: bits=%#x %#x bit=%#x word=%d",
|
|
rqb->rqb_bits[RQB_WORD(pri)],
|
|
rqb->rqb_bits[RQB_WORD(pri)] & ~RQB_BIT(pri),
|
|
RQB_BIT(pri), RQB_WORD(pri));
|
|
rqb->rqb_bits[RQB_WORD(pri)] &= ~RQB_BIT(pri);
|
|
}
|
|
|
|
/*
|
|
* Find the index of the first non-empty run queue. This is done by
|
|
* scanning the status bits, a set bit indicates a non-empty queue.
|
|
*/
|
|
static __inline int
|
|
runq_findbit(struct runq *rq)
|
|
{
|
|
struct rqbits *rqb;
|
|
int pri;
|
|
int i;
|
|
|
|
rqb = &rq->rq_status;
|
|
for (i = 0; i < RQB_LEN; i++)
|
|
if (rqb->rqb_bits[i]) {
|
|
pri = RQB_FFS(rqb->rqb_bits[i]) + (i << RQB_L2BPW);
|
|
CTR3(KTR_RUNQ, "runq_findbit: bits=%#x i=%d pri=%d",
|
|
rqb->rqb_bits[i], i, pri);
|
|
return (pri);
|
|
}
|
|
|
|
return (-1);
|
|
}
|
|
|
|
/*
|
|
* Set the status bit of the queue corresponding to priority level pri,
|
|
* indicating that it is non-empty.
|
|
*/
|
|
static __inline void
|
|
runq_setbit(struct runq *rq, int pri)
|
|
{
|
|
struct rqbits *rqb;
|
|
|
|
rqb = &rq->rq_status;
|
|
CTR4(KTR_RUNQ, "runq_setbit: bits=%#x %#x bit=%#x word=%d",
|
|
rqb->rqb_bits[RQB_WORD(pri)],
|
|
rqb->rqb_bits[RQB_WORD(pri)] | RQB_BIT(pri),
|
|
RQB_BIT(pri), RQB_WORD(pri));
|
|
rqb->rqb_bits[RQB_WORD(pri)] |= RQB_BIT(pri);
|
|
}
|
|
|
|
/*
|
|
* Add the KSE to the queue specified by its priority, and set the
|
|
* corresponding status bit.
|
|
*/
|
|
void
|
|
runq_add(struct runq *rq, struct kse *ke)
|
|
{
|
|
struct rqhead *rqh;
|
|
int pri;
|
|
|
|
pri = ke->ke_thread->td_priority / RQ_PPQ;
|
|
ke->ke_rqindex = pri;
|
|
runq_setbit(rq, pri);
|
|
rqh = &rq->rq_queues[pri];
|
|
CTR4(KTR_RUNQ, "runq_add: p=%p pri=%d %d rqh=%p",
|
|
ke->ke_proc, ke->ke_thread->td_priority, pri, rqh);
|
|
TAILQ_INSERT_TAIL(rqh, ke, ke_procq);
|
|
}
|
|
|
|
/*
|
|
* Return true if there are runnable processes of any priority on the run
|
|
* queue, false otherwise. Has no side effects, does not modify the run
|
|
* queue structure.
|
|
*/
|
|
int
|
|
runq_check(struct runq *rq)
|
|
{
|
|
struct rqbits *rqb;
|
|
int i;
|
|
|
|
rqb = &rq->rq_status;
|
|
for (i = 0; i < RQB_LEN; i++)
|
|
if (rqb->rqb_bits[i]) {
|
|
CTR2(KTR_RUNQ, "runq_check: bits=%#x i=%d",
|
|
rqb->rqb_bits[i], i);
|
|
return (1);
|
|
}
|
|
CTR0(KTR_RUNQ, "runq_check: empty");
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Find the highest priority process on the run queue.
|
|
*/
|
|
struct kse *
|
|
runq_choose(struct runq *rq)
|
|
{
|
|
struct rqhead *rqh;
|
|
struct kse *ke;
|
|
int pri;
|
|
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
while ((pri = runq_findbit(rq)) != -1) {
|
|
rqh = &rq->rq_queues[pri];
|
|
ke = TAILQ_FIRST(rqh);
|
|
KASSERT(ke != NULL, ("runq_choose: no proc on busy queue"));
|
|
CTR3(KTR_RUNQ,
|
|
"runq_choose: pri=%d kse=%p rqh=%p", pri, ke, rqh);
|
|
return (ke);
|
|
}
|
|
CTR1(KTR_RUNQ, "runq_choose: idleproc pri=%d", pri);
|
|
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* Remove the KSE from the queue specified by its priority, and clear the
|
|
* corresponding status bit if the queue becomes empty.
|
|
* Caller must set ke->ke_state afterwards.
|
|
*/
|
|
void
|
|
runq_remove(struct runq *rq, struct kse *ke)
|
|
{
|
|
struct rqhead *rqh;
|
|
int pri;
|
|
|
|
KASSERT(ke->ke_proc->p_sflag & PS_INMEM,
|
|
("runq_remove: process swapped out"));
|
|
pri = ke->ke_rqindex;
|
|
rqh = &rq->rq_queues[pri];
|
|
CTR4(KTR_RUNQ, "runq_remove: p=%p pri=%d %d rqh=%p",
|
|
ke, ke->ke_thread->td_priority, pri, rqh);
|
|
KASSERT(ke != NULL, ("runq_remove: no proc on busy queue"));
|
|
TAILQ_REMOVE(rqh, ke, ke_procq);
|
|
if (TAILQ_EMPTY(rqh)) {
|
|
CTR0(KTR_RUNQ, "runq_remove: empty");
|
|
runq_clrbit(rq, pri);
|
|
}
|
|
}
|
|
|
|
#if 0
|
|
void
|
|
panc(char *string1, char *string2)
|
|
{
|
|
printf("%s", string1);
|
|
Debugger(string2);
|
|
}
|
|
|
|
void
|
|
thread_sanity_check(struct thread *td, char *string)
|
|
{
|
|
struct proc *p;
|
|
struct ksegrp *kg;
|
|
struct kse *ke;
|
|
struct thread *td2 = NULL;
|
|
unsigned int prevpri;
|
|
int saw_lastassigned = 0;
|
|
int unassigned = 0;
|
|
int assigned = 0;
|
|
|
|
p = td->td_proc;
|
|
kg = td->td_ksegrp;
|
|
ke = td->td_kse;
|
|
|
|
|
|
if (ke) {
|
|
if (p != ke->ke_proc) {
|
|
panc(string, "wrong proc");
|
|
}
|
|
if (ke->ke_thread != td) {
|
|
panc(string, "wrong thread");
|
|
}
|
|
}
|
|
|
|
if ((p->p_flag & P_KSES) == 0) {
|
|
if (ke == NULL) {
|
|
panc(string, "non KSE thread lost kse");
|
|
}
|
|
} else {
|
|
prevpri = 0;
|
|
saw_lastassigned = 0;
|
|
unassigned = 0;
|
|
assigned = 0;
|
|
TAILQ_FOREACH(td2, &kg->kg_runq, td_runq) {
|
|
if (td2->td_priority < prevpri) {
|
|
panc(string, "thread runqueue unosorted");
|
|
}
|
|
if ((td2->td_state == TDS_RUNQ) &&
|
|
td2->td_kse &&
|
|
(td2->td_kse->ke_state != KES_ONRUNQ)) {
|
|
panc(string, "KSE wrong state");
|
|
}
|
|
prevpri = td2->td_priority;
|
|
if (td2->td_kse) {
|
|
assigned++;
|
|
if (unassigned) {
|
|
panc(string, "unassigned before assigned");
|
|
}
|
|
if (kg->kg_last_assigned == NULL) {
|
|
panc(string, "lastassigned corrupt");
|
|
}
|
|
if (saw_lastassigned) {
|
|
panc(string, "last assigned not last");
|
|
}
|
|
if (td2->td_kse->ke_thread != td2) {
|
|
panc(string, "mismatched kse/thread");
|
|
}
|
|
} else {
|
|
unassigned++;
|
|
}
|
|
if (td2 == kg->kg_last_assigned) {
|
|
saw_lastassigned = 1;
|
|
if (td2->td_kse == NULL) {
|
|
panc(string, "last assigned not assigned");
|
|
}
|
|
}
|
|
}
|
|
if (kg->kg_last_assigned && (saw_lastassigned == 0)) {
|
|
panc(string, "where on earth does lastassigned point?");
|
|
}
|
|
FOREACH_THREAD_IN_GROUP(kg, td2) {
|
|
if (((td2->td_flags & TDF_UNBOUND) == 0) &&
|
|
(TD_ON_RUNQ(td2))) {
|
|
assigned++;
|
|
if (td2->td_kse == NULL) {
|
|
panc(string, "BOUND thread with no KSE");
|
|
}
|
|
}
|
|
}
|
|
#if 0
|
|
if ((unassigned + assigned) != kg->kg_runnable) {
|
|
panc(string, "wrong number in runnable");
|
|
}
|
|
#endif
|
|
}
|
|
if (assigned == 12345) {
|
|
printf("%p %p %p %p %p %d, %d",
|
|
td, td2, ke, kg, p, assigned, saw_lastassigned);
|
|
}
|
|
}
|
|
#endif
|
|
|