1427 lines
36 KiB
C
1427 lines
36 KiB
C
/*-
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* Copyright (c) 1982, 1986, 1990, 1991, 1993
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* The Regents of the University of California. All rights reserved.
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* (c) UNIX System Laboratories, Inc.
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* All or some portions of this file are derived from material licensed
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* to the University of California by American Telephone and Telegraph
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* Co. or Unix System Laboratories, Inc. and are reproduced herein with
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* the permission of UNIX System Laboratories, Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "opt_hwpmc_hooks.h"
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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/kthread.h>
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#include <sys/mutex.h>
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#include <sys/proc.h>
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#include <sys/resourcevar.h>
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#include <sys/sched.h>
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#include <sys/smp.h>
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#include <sys/sysctl.h>
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#include <sys/sx.h>
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#include <sys/turnstile.h>
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#include <sys/umtx.h>
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#include <machine/pcb.h>
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#include <machine/smp.h>
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#ifdef HWPMC_HOOKS
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#include <sys/pmckern.h>
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#endif
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/*
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* INVERSE_ESTCPU_WEIGHT is only suitable for statclock() frequencies in
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* the range 100-256 Hz (approximately).
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*/
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#define ESTCPULIM(e) \
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min((e), INVERSE_ESTCPU_WEIGHT * (NICE_WEIGHT * (PRIO_MAX - PRIO_MIN) - \
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RQ_PPQ) + INVERSE_ESTCPU_WEIGHT - 1)
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#ifdef SMP
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#define INVERSE_ESTCPU_WEIGHT (8 * smp_cpus)
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#else
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#define INVERSE_ESTCPU_WEIGHT 8 /* 1 / (priorities per estcpu level). */
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#endif
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#define NICE_WEIGHT 1 /* Priorities per nice level. */
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/*
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* The schedulable entity that runs a context.
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* This is an extension to the thread structure and is tailored to
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* the requirements of this scheduler
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*/
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struct td_sched {
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TAILQ_ENTRY(td_sched) ts_procq; /* (j/z) Run queue. */
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struct thread *ts_thread; /* (*) Active associated thread. */
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fixpt_t ts_pctcpu; /* (j) %cpu during p_swtime. */
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u_char ts_rqindex; /* (j) Run queue index. */
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int ts_cpticks; /* (j) Ticks of cpu time. */
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struct runq *ts_runq; /* runq the thread is currently on */
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};
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/* flags kept in td_flags */
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#define TDF_DIDRUN TDF_SCHED0 /* thread actually ran. */
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#define TDF_EXIT TDF_SCHED1 /* thread is being killed. */
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#define TDF_BOUND TDF_SCHED2
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#define ts_flags ts_thread->td_flags
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#define TSF_DIDRUN TDF_DIDRUN /* thread actually ran. */
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#define TSF_EXIT TDF_EXIT /* thread is being killed. */
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#define TSF_BOUND TDF_BOUND /* stuck to one CPU */
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#define SKE_RUNQ_PCPU(ts) \
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((ts)->ts_runq != 0 && (ts)->ts_runq != &runq)
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static struct td_sched td_sched0;
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static int sched_tdcnt; /* Total runnable threads in the system. */
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static int sched_quantum; /* Roundrobin scheduling quantum in ticks. */
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#define SCHED_QUANTUM (hz / 10) /* Default sched quantum */
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static struct callout roundrobin_callout;
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static void setup_runqs(void);
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static void roundrobin(void *arg);
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static void schedcpu(void);
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static void schedcpu_thread(void);
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static void sched_priority(struct thread *td, u_char prio);
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static void sched_setup(void *dummy);
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static void maybe_resched(struct thread *td);
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static void updatepri(struct thread *td);
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static void resetpriority(struct thread *td);
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static void resetpriority_thread(struct thread *td);
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#ifdef SMP
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static int forward_wakeup(int cpunum);
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#endif
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static struct kproc_desc sched_kp = {
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"schedcpu",
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schedcpu_thread,
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NULL
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};
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SYSINIT(schedcpu, SI_SUB_RUN_SCHEDULER, SI_ORDER_FIRST, kproc_start, &sched_kp)
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SYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL)
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/*
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* Global run queue.
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*/
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static struct runq runq;
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#ifdef SMP
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/*
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* Per-CPU run queues
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*/
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static struct runq runq_pcpu[MAXCPU];
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#endif
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static void
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setup_runqs(void)
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{
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#ifdef SMP
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int i;
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for (i = 0; i < MAXCPU; ++i)
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runq_init(&runq_pcpu[i]);
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#endif
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runq_init(&runq);
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}
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static int
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sysctl_kern_quantum(SYSCTL_HANDLER_ARGS)
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{
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int error, new_val;
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new_val = sched_quantum * tick;
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error = sysctl_handle_int(oidp, &new_val, 0, req);
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if (error != 0 || req->newptr == NULL)
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return (error);
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if (new_val < tick)
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return (EINVAL);
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sched_quantum = new_val / tick;
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hogticks = 2 * sched_quantum;
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return (0);
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}
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SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RD, 0, "Scheduler");
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SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, "4BSD", 0,
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"Scheduler name");
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SYSCTL_PROC(_kern_sched, OID_AUTO, quantum, CTLTYPE_INT | CTLFLAG_RW,
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0, sizeof sched_quantum, sysctl_kern_quantum, "I",
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"Roundrobin scheduling quantum in microseconds");
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#ifdef SMP
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/* Enable forwarding of wakeups to all other cpus */
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SYSCTL_NODE(_kern_sched, OID_AUTO, ipiwakeup, CTLFLAG_RD, NULL, "Kernel SMP");
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static int forward_wakeup_enabled = 1;
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SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, enabled, CTLFLAG_RW,
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&forward_wakeup_enabled, 0,
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"Forwarding of wakeup to idle CPUs");
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static int forward_wakeups_requested = 0;
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SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, requested, CTLFLAG_RD,
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&forward_wakeups_requested, 0,
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"Requests for Forwarding of wakeup to idle CPUs");
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static int forward_wakeups_delivered = 0;
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SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, delivered, CTLFLAG_RD,
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&forward_wakeups_delivered, 0,
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"Completed Forwarding of wakeup to idle CPUs");
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static int forward_wakeup_use_mask = 1;
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SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, usemask, CTLFLAG_RW,
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&forward_wakeup_use_mask, 0,
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"Use the mask of idle cpus");
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static int forward_wakeup_use_loop = 0;
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SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, useloop, CTLFLAG_RW,
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&forward_wakeup_use_loop, 0,
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"Use a loop to find idle cpus");
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static int forward_wakeup_use_single = 0;
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SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, onecpu, CTLFLAG_RW,
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&forward_wakeup_use_single, 0,
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"Only signal one idle cpu");
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static int forward_wakeup_use_htt = 0;
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SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, htt2, CTLFLAG_RW,
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&forward_wakeup_use_htt, 0,
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"account for htt");
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#endif
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#if 0
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static int sched_followon = 0;
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SYSCTL_INT(_kern_sched, OID_AUTO, followon, CTLFLAG_RW,
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&sched_followon, 0,
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"allow threads to share a quantum");
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#endif
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static __inline void
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sched_load_add(void)
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{
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sched_tdcnt++;
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CTR1(KTR_SCHED, "global load: %d", sched_tdcnt);
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}
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static __inline void
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sched_load_rem(void)
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{
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sched_tdcnt--;
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CTR1(KTR_SCHED, "global load: %d", sched_tdcnt);
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}
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/*
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* Arrange to reschedule if necessary, taking the priorities and
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* schedulers into account.
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*/
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static void
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maybe_resched(struct thread *td)
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{
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THREAD_LOCK_ASSERT(td, MA_OWNED);
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if (td->td_priority < curthread->td_priority)
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curthread->td_flags |= TDF_NEEDRESCHED;
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}
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/*
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* Force switch among equal priority processes every 100ms.
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* We don't actually need to force a context switch of the current process.
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* The act of firing the event triggers a context switch to softclock() and
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* then switching back out again which is equivalent to a preemption, thus
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* no further work is needed on the local CPU.
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*/
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/* ARGSUSED */
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static void
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roundrobin(void *arg)
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{
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#ifdef SMP
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mtx_lock_spin(&sched_lock);
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forward_roundrobin();
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mtx_unlock_spin(&sched_lock);
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#endif
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callout_reset(&roundrobin_callout, sched_quantum, roundrobin, NULL);
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}
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/*
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* Constants for digital decay and forget:
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* 90% of (td_estcpu) usage in 5 * loadav time
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* 95% of (ts_pctcpu) usage in 60 seconds (load insensitive)
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* Note that, as ps(1) mentions, this can let percentages
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* total over 100% (I've seen 137.9% for 3 processes).
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*
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* Note that schedclock() updates td_estcpu and p_cpticks asynchronously.
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*
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* We wish to decay away 90% of td_estcpu in (5 * loadavg) seconds.
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* That is, the system wants to compute a value of decay such
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* that the following for loop:
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* for (i = 0; i < (5 * loadavg); i++)
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* td_estcpu *= decay;
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* will compute
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* td_estcpu *= 0.1;
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* for all values of loadavg:
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*
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* Mathematically this loop can be expressed by saying:
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* decay ** (5 * loadavg) ~= .1
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*
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* The system computes decay as:
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* decay = (2 * loadavg) / (2 * loadavg + 1)
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*
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* We wish to prove that the system's computation of decay
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* will always fulfill the equation:
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* decay ** (5 * loadavg) ~= .1
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*
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* If we compute b as:
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* b = 2 * loadavg
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* then
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* decay = b / (b + 1)
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*
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* We now need to prove two things:
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* 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1)
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* 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg)
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*
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* Facts:
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* For x close to zero, exp(x) =~ 1 + x, since
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* exp(x) = 0! + x**1/1! + x**2/2! + ... .
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* therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b.
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* For x close to zero, ln(1+x) =~ x, since
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* ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1
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* therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1).
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* ln(.1) =~ -2.30
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*
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* Proof of (1):
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* Solve (factor)**(power) =~ .1 given power (5*loadav):
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* solving for factor,
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* ln(factor) =~ (-2.30/5*loadav), or
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* factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) =
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* exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED
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*
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* Proof of (2):
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* Solve (factor)**(power) =~ .1 given factor == (b/(b+1)):
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* solving for power,
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* power*ln(b/(b+1)) =~ -2.30, or
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* power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED
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*
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* Actual power values for the implemented algorithm are as follows:
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* loadav: 1 2 3 4
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* power: 5.68 10.32 14.94 19.55
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*/
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/* calculations for digital decay to forget 90% of usage in 5*loadav sec */
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#define loadfactor(loadav) (2 * (loadav))
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#define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE))
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/* decay 95% of `ts_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */
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static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */
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SYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, "");
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/*
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* If `ccpu' is not equal to `exp(-1/20)' and you still want to use the
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* faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below
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* and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT).
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*
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* To estimate CCPU_SHIFT for exp(-1/20), the following formula was used:
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* 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits).
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*
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* If you don't want to bother with the faster/more-accurate formula, you
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* can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate
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* (more general) method of calculating the %age of CPU used by a process.
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*/
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#define CCPU_SHIFT 11
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/*
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* Recompute process priorities, every hz ticks.
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* MP-safe, called without the Giant mutex.
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*/
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/* ARGSUSED */
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static void
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schedcpu(void)
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{
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register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]);
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struct thread *td;
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struct proc *p;
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struct td_sched *ts;
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int awake, realstathz;
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realstathz = stathz ? stathz : hz;
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sx_slock(&allproc_lock);
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FOREACH_PROC_IN_SYSTEM(p) {
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PROC_SLOCK(p);
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/*
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* Increment time in/out of memory. We ignore overflow; with
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* 16-bit int's (remember them?) overflow takes 45 days.
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*/
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p->p_swtime++;
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FOREACH_THREAD_IN_PROC(p, td) {
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awake = 0;
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thread_lock(td);
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ts = td->td_sched;
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/*
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* Increment sleep time (if sleeping). We
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* ignore overflow, as above.
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*/
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/*
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* The td_sched slptimes are not touched in wakeup
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* because the thread may not HAVE everything in
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* memory? XXX I think this is out of date.
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*/
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if (TD_ON_RUNQ(td)) {
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awake = 1;
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ts->ts_flags &= ~TSF_DIDRUN;
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} else if (TD_IS_RUNNING(td)) {
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awake = 1;
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/* Do not clear TSF_DIDRUN */
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} else if (ts->ts_flags & TSF_DIDRUN) {
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awake = 1;
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ts->ts_flags &= ~TSF_DIDRUN;
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}
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/*
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* ts_pctcpu is only for ps and ttyinfo().
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* Do it per td_sched, and add them up at the end?
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* XXXKSE
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*/
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ts->ts_pctcpu = (ts->ts_pctcpu * ccpu) >> FSHIFT;
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/*
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* If the td_sched has been idle the entire second,
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* stop recalculating its priority until
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* it wakes up.
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*/
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if (ts->ts_cpticks != 0) {
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#if (FSHIFT >= CCPU_SHIFT)
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ts->ts_pctcpu += (realstathz == 100)
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? ((fixpt_t) ts->ts_cpticks) <<
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(FSHIFT - CCPU_SHIFT) :
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100 * (((fixpt_t) ts->ts_cpticks)
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<< (FSHIFT - CCPU_SHIFT)) / realstathz;
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#else
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ts->ts_pctcpu += ((FSCALE - ccpu) *
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(ts->ts_cpticks *
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FSCALE / realstathz)) >> FSHIFT;
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#endif
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ts->ts_cpticks = 0;
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}
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/*
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* If there are ANY running threads in this process,
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* then don't count it as sleeping.
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XXX this is broken
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*/
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if (awake) {
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if (td->td_slptime > 1) {
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/*
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* In an ideal world, this should not
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* happen, because whoever woke us
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* up from the long sleep should have
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* unwound the slptime and reset our
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* priority before we run at the stale
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* priority. Should KASSERT at some
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* point when all the cases are fixed.
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*/
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updatepri(td);
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}
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td->td_slptime = 0;
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} else
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td->td_slptime++;
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if (td->td_slptime > 1) {
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thread_unlock(td);
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continue;
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}
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td->td_estcpu = decay_cpu(loadfac, td->td_estcpu);
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resetpriority(td);
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resetpriority_thread(td);
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thread_unlock(td);
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} /* end of thread loop */
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PROC_SUNLOCK(p);
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} /* end of process loop */
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sx_sunlock(&allproc_lock);
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}
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|
|
/*
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|
* Main loop for a kthread that executes schedcpu once a second.
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|
*/
|
|
static void
|
|
schedcpu_thread(void)
|
|
{
|
|
|
|
for (;;) {
|
|
schedcpu();
|
|
pause("-", hz);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Recalculate the priority of a process after it has slept for a while.
|
|
* For all load averages >= 1 and max td_estcpu of 255, sleeping for at
|
|
* least six times the loadfactor will decay td_estcpu to zero.
|
|
*/
|
|
static void
|
|
updatepri(struct thread *td)
|
|
{
|
|
register fixpt_t loadfac;
|
|
register unsigned int newcpu;
|
|
|
|
loadfac = loadfactor(averunnable.ldavg[0]);
|
|
if (td->td_slptime > 5 * loadfac)
|
|
td->td_estcpu = 0;
|
|
else {
|
|
newcpu = td->td_estcpu;
|
|
td->td_slptime--; /* was incremented in schedcpu() */
|
|
while (newcpu && --td->td_slptime)
|
|
newcpu = decay_cpu(loadfac, newcpu);
|
|
td->td_estcpu = newcpu;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Compute the priority of a process when running in user mode.
|
|
* Arrange to reschedule if the resulting priority is better
|
|
* than that of the current process.
|
|
*/
|
|
static void
|
|
resetpriority(struct thread *td)
|
|
{
|
|
register unsigned int newpriority;
|
|
|
|
if (td->td_pri_class == PRI_TIMESHARE) {
|
|
newpriority = PUSER + td->td_estcpu / INVERSE_ESTCPU_WEIGHT +
|
|
NICE_WEIGHT * (td->td_proc->p_nice - PRIO_MIN);
|
|
newpriority = min(max(newpriority, PRI_MIN_TIMESHARE),
|
|
PRI_MAX_TIMESHARE);
|
|
sched_user_prio(td, newpriority);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Update the thread's priority when the associated process's user
|
|
* priority changes.
|
|
*/
|
|
static void
|
|
resetpriority_thread(struct thread *td)
|
|
{
|
|
|
|
/* Only change threads with a time sharing user priority. */
|
|
if (td->td_priority < PRI_MIN_TIMESHARE ||
|
|
td->td_priority > PRI_MAX_TIMESHARE)
|
|
return;
|
|
|
|
/* XXX the whole needresched thing is broken, but not silly. */
|
|
maybe_resched(td);
|
|
|
|
sched_prio(td, td->td_user_pri);
|
|
}
|
|
|
|
/* ARGSUSED */
|
|
static void
|
|
sched_setup(void *dummy)
|
|
{
|
|
setup_runqs();
|
|
|
|
if (sched_quantum == 0)
|
|
sched_quantum = SCHED_QUANTUM;
|
|
hogticks = 2 * sched_quantum;
|
|
|
|
callout_init(&roundrobin_callout, CALLOUT_MPSAFE);
|
|
|
|
/* Kick off timeout driven events by calling first time. */
|
|
roundrobin(NULL);
|
|
|
|
/* Account for thread0. */
|
|
sched_load_add();
|
|
}
|
|
|
|
/* External interfaces start here */
|
|
/*
|
|
* Very early in the boot some setup of scheduler-specific
|
|
* parts of proc0 and of some scheduler resources needs to be done.
|
|
* Called from:
|
|
* proc0_init()
|
|
*/
|
|
void
|
|
schedinit(void)
|
|
{
|
|
/*
|
|
* Set up the scheduler specific parts of proc0.
|
|
*/
|
|
proc0.p_sched = NULL; /* XXX */
|
|
thread0.td_sched = &td_sched0;
|
|
thread0.td_lock = &sched_lock;
|
|
td_sched0.ts_thread = &thread0;
|
|
}
|
|
|
|
int
|
|
sched_runnable(void)
|
|
{
|
|
#ifdef SMP
|
|
return runq_check(&runq) + runq_check(&runq_pcpu[PCPU_GET(cpuid)]);
|
|
#else
|
|
return runq_check(&runq);
|
|
#endif
|
|
}
|
|
|
|
int
|
|
sched_rr_interval(void)
|
|
{
|
|
if (sched_quantum == 0)
|
|
sched_quantum = SCHED_QUANTUM;
|
|
return (sched_quantum);
|
|
}
|
|
|
|
/*
|
|
* We adjust the priority of the current process. The priority of
|
|
* a process gets worse as it accumulates CPU time. The cpu usage
|
|
* estimator (td_estcpu) is increased here. resetpriority() will
|
|
* compute a different priority each time td_estcpu increases by
|
|
* INVERSE_ESTCPU_WEIGHT
|
|
* (until MAXPRI is reached). The cpu usage estimator ramps up
|
|
* quite quickly when the process is running (linearly), and decays
|
|
* away exponentially, at a rate which is proportionally slower when
|
|
* the system is busy. The basic principle is that the system will
|
|
* 90% forget that the process used a lot of CPU time in 5 * loadav
|
|
* seconds. This causes the system to favor processes which haven't
|
|
* run much recently, and to round-robin among other processes.
|
|
*/
|
|
void
|
|
sched_clock(struct thread *td)
|
|
{
|
|
struct td_sched *ts;
|
|
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
ts = td->td_sched;
|
|
|
|
ts->ts_cpticks++;
|
|
td->td_estcpu = ESTCPULIM(td->td_estcpu + 1);
|
|
if ((td->td_estcpu % INVERSE_ESTCPU_WEIGHT) == 0) {
|
|
resetpriority(td);
|
|
resetpriority_thread(td);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* charge childs scheduling cpu usage to parent.
|
|
*/
|
|
void
|
|
sched_exit(struct proc *p, struct thread *td)
|
|
{
|
|
|
|
CTR3(KTR_SCHED, "sched_exit: %p(%s) prio %d",
|
|
td, td->td_proc->p_comm, td->td_priority);
|
|
PROC_SLOCK_ASSERT(p, MA_OWNED);
|
|
sched_exit_thread(FIRST_THREAD_IN_PROC(p), td);
|
|
}
|
|
|
|
void
|
|
sched_exit_thread(struct thread *td, struct thread *child)
|
|
{
|
|
|
|
CTR3(KTR_SCHED, "sched_exit_thread: %p(%s) prio %d",
|
|
child, child->td_proc->p_comm, child->td_priority);
|
|
thread_lock(td);
|
|
td->td_estcpu = ESTCPULIM(td->td_estcpu + child->td_estcpu);
|
|
thread_unlock(td);
|
|
mtx_lock_spin(&sched_lock);
|
|
if ((child->td_proc->p_flag & P_NOLOAD) == 0)
|
|
sched_load_rem();
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
|
|
void
|
|
sched_fork(struct thread *td, struct thread *childtd)
|
|
{
|
|
sched_fork_thread(td, childtd);
|
|
}
|
|
|
|
void
|
|
sched_fork_thread(struct thread *td, struct thread *childtd)
|
|
{
|
|
childtd->td_estcpu = td->td_estcpu;
|
|
childtd->td_lock = &sched_lock;
|
|
sched_newthread(childtd);
|
|
}
|
|
|
|
void
|
|
sched_nice(struct proc *p, int nice)
|
|
{
|
|
struct thread *td;
|
|
|
|
PROC_LOCK_ASSERT(p, MA_OWNED);
|
|
PROC_SLOCK_ASSERT(p, MA_OWNED);
|
|
p->p_nice = nice;
|
|
FOREACH_THREAD_IN_PROC(p, td) {
|
|
thread_lock(td);
|
|
resetpriority(td);
|
|
resetpriority_thread(td);
|
|
thread_unlock(td);
|
|
}
|
|
}
|
|
|
|
void
|
|
sched_class(struct thread *td, int class)
|
|
{
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
td->td_pri_class = class;
|
|
}
|
|
|
|
/*
|
|
* Adjust the priority of a thread.
|
|
*/
|
|
static void
|
|
sched_priority(struct thread *td, u_char prio)
|
|
{
|
|
CTR6(KTR_SCHED, "sched_prio: %p(%s) prio %d newprio %d by %p(%s)",
|
|
td, td->td_proc->p_comm, td->td_priority, prio, curthread,
|
|
curthread->td_proc->p_comm);
|
|
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
if (td->td_priority == prio)
|
|
return;
|
|
td->td_priority = prio;
|
|
if (TD_ON_RUNQ(td) &&
|
|
td->td_sched->ts_rqindex != (prio / RQ_PPQ)) {
|
|
sched_rem(td);
|
|
sched_add(td, SRQ_BORING);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Update a thread's priority when it is lent another thread's
|
|
* priority.
|
|
*/
|
|
void
|
|
sched_lend_prio(struct thread *td, u_char prio)
|
|
{
|
|
|
|
td->td_flags |= TDF_BORROWING;
|
|
sched_priority(td, prio);
|
|
}
|
|
|
|
/*
|
|
* Restore a thread's priority when priority propagation is
|
|
* over. The prio argument is the minimum priority the thread
|
|
* needs to have to satisfy other possible priority lending
|
|
* requests. If the thread's regulary priority is less
|
|
* important than prio the thread will keep a priority boost
|
|
* of prio.
|
|
*/
|
|
void
|
|
sched_unlend_prio(struct thread *td, u_char prio)
|
|
{
|
|
u_char base_pri;
|
|
|
|
if (td->td_base_pri >= PRI_MIN_TIMESHARE &&
|
|
td->td_base_pri <= PRI_MAX_TIMESHARE)
|
|
base_pri = td->td_user_pri;
|
|
else
|
|
base_pri = td->td_base_pri;
|
|
if (prio >= base_pri) {
|
|
td->td_flags &= ~TDF_BORROWING;
|
|
sched_prio(td, base_pri);
|
|
} else
|
|
sched_lend_prio(td, prio);
|
|
}
|
|
|
|
void
|
|
sched_prio(struct thread *td, u_char prio)
|
|
{
|
|
u_char oldprio;
|
|
|
|
/* First, update the base priority. */
|
|
td->td_base_pri = prio;
|
|
|
|
/*
|
|
* If the thread is borrowing another thread's priority, don't ever
|
|
* lower the priority.
|
|
*/
|
|
if (td->td_flags & TDF_BORROWING && td->td_priority < prio)
|
|
return;
|
|
|
|
/* Change the real priority. */
|
|
oldprio = td->td_priority;
|
|
sched_priority(td, prio);
|
|
|
|
/*
|
|
* If the thread is on a turnstile, then let the turnstile update
|
|
* its state.
|
|
*/
|
|
if (TD_ON_LOCK(td) && oldprio != prio)
|
|
turnstile_adjust(td, oldprio);
|
|
}
|
|
|
|
void
|
|
sched_user_prio(struct thread *td, u_char prio)
|
|
{
|
|
u_char oldprio;
|
|
|
|
td->td_base_user_pri = prio;
|
|
if (td->td_flags & TDF_UBORROWING && td->td_user_pri <= prio)
|
|
return;
|
|
oldprio = td->td_user_pri;
|
|
td->td_user_pri = prio;
|
|
|
|
if (TD_ON_UPILOCK(td) && oldprio != prio)
|
|
umtx_pi_adjust(td, oldprio);
|
|
}
|
|
|
|
void
|
|
sched_lend_user_prio(struct thread *td, u_char prio)
|
|
{
|
|
u_char oldprio;
|
|
|
|
td->td_flags |= TDF_UBORROWING;
|
|
|
|
oldprio = td->td_user_pri;
|
|
td->td_user_pri = prio;
|
|
|
|
if (TD_ON_UPILOCK(td) && oldprio != prio)
|
|
umtx_pi_adjust(td, oldprio);
|
|
}
|
|
|
|
void
|
|
sched_unlend_user_prio(struct thread *td, u_char prio)
|
|
{
|
|
u_char base_pri;
|
|
|
|
base_pri = td->td_base_user_pri;
|
|
if (prio >= base_pri) {
|
|
td->td_flags &= ~TDF_UBORROWING;
|
|
sched_user_prio(td, base_pri);
|
|
} else
|
|
sched_lend_user_prio(td, prio);
|
|
}
|
|
|
|
void
|
|
sched_sleep(struct thread *td)
|
|
{
|
|
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
td->td_slptime = 0;
|
|
}
|
|
|
|
void
|
|
sched_switch(struct thread *td, struct thread *newtd, int flags)
|
|
{
|
|
struct td_sched *ts;
|
|
struct proc *p;
|
|
|
|
ts = td->td_sched;
|
|
p = td->td_proc;
|
|
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
/*
|
|
* Switch to the sched lock to fix things up and pick
|
|
* a new thread.
|
|
*/
|
|
if (td->td_lock != &sched_lock) {
|
|
mtx_lock_spin(&sched_lock);
|
|
thread_unlock(td);
|
|
}
|
|
|
|
if ((p->p_flag & P_NOLOAD) == 0)
|
|
sched_load_rem();
|
|
|
|
if (newtd)
|
|
newtd->td_flags |= (td->td_flags & TDF_NEEDRESCHED);
|
|
|
|
td->td_lastcpu = td->td_oncpu;
|
|
td->td_flags &= ~TDF_NEEDRESCHED;
|
|
td->td_owepreempt = 0;
|
|
td->td_oncpu = NOCPU;
|
|
/*
|
|
* At the last moment, if this thread is still marked RUNNING,
|
|
* then put it back on the run queue as it has not been suspended
|
|
* or stopped or any thing else similar. We never put the idle
|
|
* threads on the run queue, however.
|
|
*/
|
|
if (td->td_flags & TDF_IDLETD) {
|
|
TD_SET_CAN_RUN(td);
|
|
#ifdef SMP
|
|
idle_cpus_mask &= ~PCPU_GET(cpumask);
|
|
#endif
|
|
} else {
|
|
if (TD_IS_RUNNING(td)) {
|
|
/* Put us back on the run queue. */
|
|
sched_add(td, (flags & SW_PREEMPT) ?
|
|
SRQ_OURSELF|SRQ_YIELDING|SRQ_PREEMPTED :
|
|
SRQ_OURSELF|SRQ_YIELDING);
|
|
}
|
|
}
|
|
if (newtd) {
|
|
/*
|
|
* The thread we are about to run needs to be counted
|
|
* as if it had been added to the run queue and selected.
|
|
* It came from:
|
|
* * A preemption
|
|
* * An upcall
|
|
* * A followon
|
|
*/
|
|
KASSERT((newtd->td_inhibitors == 0),
|
|
("trying to run inhibited thread"));
|
|
newtd->td_sched->ts_flags |= TSF_DIDRUN;
|
|
TD_SET_RUNNING(newtd);
|
|
if ((newtd->td_proc->p_flag & P_NOLOAD) == 0)
|
|
sched_load_add();
|
|
} else {
|
|
newtd = choosethread();
|
|
}
|
|
MPASS(newtd->td_lock == &sched_lock);
|
|
|
|
if (td != newtd) {
|
|
#ifdef HWPMC_HOOKS
|
|
if (PMC_PROC_IS_USING_PMCS(td->td_proc))
|
|
PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT);
|
|
#endif
|
|
|
|
/* I feel sleepy */
|
|
cpu_switch(td, newtd, td->td_lock);
|
|
/*
|
|
* Where am I? What year is it?
|
|
* We are in the same thread that went to sleep above,
|
|
* but any amount of time may have passed. All out context
|
|
* will still be available as will local variables.
|
|
* PCPU values however may have changed as we may have
|
|
* changed CPU so don't trust cached values of them.
|
|
* New threads will go to fork_exit() instead of here
|
|
* so if you change things here you may need to change
|
|
* things there too.
|
|
* If the thread above was exiting it will never wake
|
|
* up again here, so either it has saved everything it
|
|
* needed to, or the thread_wait() or wait() will
|
|
* need to reap it.
|
|
*/
|
|
#ifdef HWPMC_HOOKS
|
|
if (PMC_PROC_IS_USING_PMCS(td->td_proc))
|
|
PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN);
|
|
#endif
|
|
}
|
|
|
|
#ifdef SMP
|
|
if (td->td_flags & TDF_IDLETD)
|
|
idle_cpus_mask |= PCPU_GET(cpumask);
|
|
#endif
|
|
sched_lock.mtx_lock = (uintptr_t)td;
|
|
td->td_oncpu = PCPU_GET(cpuid);
|
|
MPASS(td->td_lock == &sched_lock);
|
|
}
|
|
|
|
void
|
|
sched_wakeup(struct thread *td)
|
|
{
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
if (td->td_slptime > 1) {
|
|
updatepri(td);
|
|
resetpriority(td);
|
|
}
|
|
td->td_slptime = 0;
|
|
sched_add(td, SRQ_BORING);
|
|
}
|
|
|
|
#ifdef SMP
|
|
/* enable HTT_2 if you have a 2-way HTT cpu.*/
|
|
static int
|
|
forward_wakeup(int cpunum)
|
|
{
|
|
cpumask_t map, me, dontuse;
|
|
cpumask_t map2;
|
|
struct pcpu *pc;
|
|
cpumask_t id, map3;
|
|
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
|
|
CTR0(KTR_RUNQ, "forward_wakeup()");
|
|
|
|
if ((!forward_wakeup_enabled) ||
|
|
(forward_wakeup_use_mask == 0 && forward_wakeup_use_loop == 0))
|
|
return (0);
|
|
if (!smp_started || cold || panicstr)
|
|
return (0);
|
|
|
|
forward_wakeups_requested++;
|
|
|
|
/*
|
|
* check the idle mask we received against what we calculated before
|
|
* in the old version.
|
|
*/
|
|
me = PCPU_GET(cpumask);
|
|
/*
|
|
* don't bother if we should be doing it ourself..
|
|
*/
|
|
if ((me & idle_cpus_mask) && (cpunum == NOCPU || me == (1 << cpunum)))
|
|
return (0);
|
|
|
|
dontuse = me | stopped_cpus | hlt_cpus_mask;
|
|
map3 = 0;
|
|
if (forward_wakeup_use_loop) {
|
|
SLIST_FOREACH(pc, &cpuhead, pc_allcpu) {
|
|
id = pc->pc_cpumask;
|
|
if ( (id & dontuse) == 0 &&
|
|
pc->pc_curthread == pc->pc_idlethread) {
|
|
map3 |= id;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (forward_wakeup_use_mask) {
|
|
map = 0;
|
|
map = idle_cpus_mask & ~dontuse;
|
|
|
|
/* If they are both on, compare and use loop if different */
|
|
if (forward_wakeup_use_loop) {
|
|
if (map != map3) {
|
|
printf("map (%02X) != map3 (%02X)\n",
|
|
map, map3);
|
|
map = map3;
|
|
}
|
|
}
|
|
} else {
|
|
map = map3;
|
|
}
|
|
/* If we only allow a specific CPU, then mask off all the others */
|
|
if (cpunum != NOCPU) {
|
|
KASSERT((cpunum <= mp_maxcpus),("forward_wakeup: bad cpunum."));
|
|
map &= (1 << cpunum);
|
|
} else {
|
|
/* Try choose an idle die. */
|
|
if (forward_wakeup_use_htt) {
|
|
map2 = (map & (map >> 1)) & 0x5555;
|
|
if (map2) {
|
|
map = map2;
|
|
}
|
|
}
|
|
|
|
/* set only one bit */
|
|
if (forward_wakeup_use_single) {
|
|
map = map & ((~map) + 1);
|
|
}
|
|
}
|
|
if (map) {
|
|
forward_wakeups_delivered++;
|
|
ipi_selected(map, IPI_AST);
|
|
return (1);
|
|
}
|
|
if (cpunum == NOCPU)
|
|
printf("forward_wakeup: Idle processor not found\n");
|
|
return (0);
|
|
}
|
|
#endif
|
|
|
|
#ifdef SMP
|
|
static void kick_other_cpu(int pri,int cpuid);
|
|
|
|
static void
|
|
kick_other_cpu(int pri,int cpuid)
|
|
{
|
|
struct pcpu * pcpu = pcpu_find(cpuid);
|
|
int cpri = pcpu->pc_curthread->td_priority;
|
|
|
|
if (idle_cpus_mask & pcpu->pc_cpumask) {
|
|
forward_wakeups_delivered++;
|
|
ipi_selected(pcpu->pc_cpumask, IPI_AST);
|
|
return;
|
|
}
|
|
|
|
if (pri >= cpri)
|
|
return;
|
|
|
|
#if defined(IPI_PREEMPTION) && defined(PREEMPTION)
|
|
#if !defined(FULL_PREEMPTION)
|
|
if (pri <= PRI_MAX_ITHD)
|
|
#endif /* ! FULL_PREEMPTION */
|
|
{
|
|
ipi_selected(pcpu->pc_cpumask, IPI_PREEMPT);
|
|
return;
|
|
}
|
|
#endif /* defined(IPI_PREEMPTION) && defined(PREEMPTION) */
|
|
|
|
pcpu->pc_curthread->td_flags |= TDF_NEEDRESCHED;
|
|
ipi_selected( pcpu->pc_cpumask , IPI_AST);
|
|
return;
|
|
}
|
|
#endif /* SMP */
|
|
|
|
void
|
|
sched_add(struct thread *td, int flags)
|
|
#ifdef SMP
|
|
{
|
|
struct td_sched *ts;
|
|
int forwarded = 0;
|
|
int cpu;
|
|
int single_cpu = 0;
|
|
|
|
ts = td->td_sched;
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
KASSERT((td->td_inhibitors == 0),
|
|
("sched_add: trying to run inhibited thread"));
|
|
KASSERT((TD_CAN_RUN(td) || TD_IS_RUNNING(td)),
|
|
("sched_add: bad thread state"));
|
|
KASSERT(td->td_proc->p_sflag & PS_INMEM,
|
|
("sched_add: process swapped out"));
|
|
CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)",
|
|
td, td->td_proc->p_comm, td->td_priority, curthread,
|
|
curthread->td_proc->p_comm);
|
|
/*
|
|
* Now that the thread is moving to the run-queue, set the lock
|
|
* to the scheduler's lock.
|
|
*/
|
|
if (td->td_lock != &sched_lock) {
|
|
mtx_lock_spin(&sched_lock);
|
|
thread_lock_set(td, &sched_lock);
|
|
}
|
|
TD_SET_RUNQ(td);
|
|
|
|
if (td->td_pinned != 0) {
|
|
cpu = td->td_lastcpu;
|
|
ts->ts_runq = &runq_pcpu[cpu];
|
|
single_cpu = 1;
|
|
CTR3(KTR_RUNQ,
|
|
"sched_add: Put td_sched:%p(td:%p) on cpu%d runq", ts, td, cpu);
|
|
} else if ((ts)->ts_flags & TSF_BOUND) {
|
|
/* Find CPU from bound runq */
|
|
KASSERT(SKE_RUNQ_PCPU(ts),("sched_add: bound td_sched not on cpu runq"));
|
|
cpu = ts->ts_runq - &runq_pcpu[0];
|
|
single_cpu = 1;
|
|
CTR3(KTR_RUNQ,
|
|
"sched_add: Put td_sched:%p(td:%p) on cpu%d runq", ts, td, cpu);
|
|
} else {
|
|
CTR2(KTR_RUNQ,
|
|
"sched_add: adding td_sched:%p (td:%p) to gbl runq", ts, td);
|
|
cpu = NOCPU;
|
|
ts->ts_runq = &runq;
|
|
}
|
|
|
|
if (single_cpu && (cpu != PCPU_GET(cpuid))) {
|
|
kick_other_cpu(td->td_priority,cpu);
|
|
} else {
|
|
|
|
if (!single_cpu) {
|
|
cpumask_t me = PCPU_GET(cpumask);
|
|
int idle = idle_cpus_mask & me;
|
|
|
|
if (!idle && ((flags & SRQ_INTR) == 0) &&
|
|
(idle_cpus_mask & ~(hlt_cpus_mask | me)))
|
|
forwarded = forward_wakeup(cpu);
|
|
}
|
|
|
|
if (!forwarded) {
|
|
if ((flags & SRQ_YIELDING) == 0 && maybe_preempt(td))
|
|
return;
|
|
else
|
|
maybe_resched(td);
|
|
}
|
|
}
|
|
|
|
if ((td->td_proc->p_flag & P_NOLOAD) == 0)
|
|
sched_load_add();
|
|
runq_add(ts->ts_runq, ts, flags);
|
|
}
|
|
#else /* SMP */
|
|
{
|
|
struct td_sched *ts;
|
|
ts = td->td_sched;
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
KASSERT((td->td_inhibitors == 0),
|
|
("sched_add: trying to run inhibited thread"));
|
|
KASSERT((TD_CAN_RUN(td) || TD_IS_RUNNING(td)),
|
|
("sched_add: bad thread state"));
|
|
KASSERT(td->td_proc->p_sflag & PS_INMEM,
|
|
("sched_add: process swapped out"));
|
|
CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)",
|
|
td, td->td_proc->p_comm, td->td_priority, curthread,
|
|
curthread->td_proc->p_comm);
|
|
/*
|
|
* Now that the thread is moving to the run-queue, set the lock
|
|
* to the scheduler's lock.
|
|
*/
|
|
if (td->td_lock != &sched_lock) {
|
|
mtx_lock_spin(&sched_lock);
|
|
thread_lock_set(td, &sched_lock);
|
|
}
|
|
TD_SET_RUNQ(td);
|
|
CTR2(KTR_RUNQ, "sched_add: adding td_sched:%p (td:%p) to runq", ts, td);
|
|
ts->ts_runq = &runq;
|
|
|
|
/*
|
|
* If we are yielding (on the way out anyhow)
|
|
* or the thread being saved is US,
|
|
* then don't try be smart about preemption
|
|
* or kicking off another CPU
|
|
* as it won't help and may hinder.
|
|
* In the YIEDLING case, we are about to run whoever is
|
|
* being put in the queue anyhow, and in the
|
|
* OURSELF case, we are puting ourself on the run queue
|
|
* which also only happens when we are about to yield.
|
|
*/
|
|
if((flags & SRQ_YIELDING) == 0) {
|
|
if (maybe_preempt(td))
|
|
return;
|
|
}
|
|
if ((td->td_proc->p_flag & P_NOLOAD) == 0)
|
|
sched_load_add();
|
|
runq_add(ts->ts_runq, ts, flags);
|
|
maybe_resched(td);
|
|
}
|
|
#endif /* SMP */
|
|
|
|
void
|
|
sched_rem(struct thread *td)
|
|
{
|
|
struct td_sched *ts;
|
|
|
|
ts = td->td_sched;
|
|
KASSERT(td->td_proc->p_sflag & PS_INMEM,
|
|
("sched_rem: process swapped out"));
|
|
KASSERT(TD_ON_RUNQ(td),
|
|
("sched_rem: thread not on run queue"));
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
CTR5(KTR_SCHED, "sched_rem: %p(%s) prio %d by %p(%s)",
|
|
td, td->td_proc->p_comm, td->td_priority, curthread,
|
|
curthread->td_proc->p_comm);
|
|
|
|
if ((td->td_proc->p_flag & P_NOLOAD) == 0)
|
|
sched_load_rem();
|
|
runq_remove(ts->ts_runq, ts);
|
|
TD_SET_CAN_RUN(td);
|
|
}
|
|
|
|
/*
|
|
* Select threads to run.
|
|
* Notice that the running threads still consume a slot.
|
|
*/
|
|
struct thread *
|
|
sched_choose(void)
|
|
{
|
|
struct td_sched *ts;
|
|
struct runq *rq;
|
|
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
#ifdef SMP
|
|
struct td_sched *kecpu;
|
|
|
|
rq = &runq;
|
|
ts = runq_choose(&runq);
|
|
kecpu = runq_choose(&runq_pcpu[PCPU_GET(cpuid)]);
|
|
|
|
if (ts == NULL ||
|
|
(kecpu != NULL &&
|
|
kecpu->ts_thread->td_priority < ts->ts_thread->td_priority)) {
|
|
CTR2(KTR_RUNQ, "choosing td_sched %p from pcpu runq %d", kecpu,
|
|
PCPU_GET(cpuid));
|
|
ts = kecpu;
|
|
rq = &runq_pcpu[PCPU_GET(cpuid)];
|
|
} else {
|
|
CTR1(KTR_RUNQ, "choosing td_sched %p from main runq", ts);
|
|
}
|
|
|
|
#else
|
|
rq = &runq;
|
|
ts = runq_choose(&runq);
|
|
#endif
|
|
|
|
if (ts) {
|
|
runq_remove(rq, ts);
|
|
ts->ts_flags |= TSF_DIDRUN;
|
|
|
|
KASSERT(ts->ts_thread->td_proc->p_sflag & PS_INMEM,
|
|
("sched_choose: process swapped out"));
|
|
return (ts->ts_thread);
|
|
}
|
|
return (PCPU_GET(idlethread));
|
|
}
|
|
|
|
void
|
|
sched_userret(struct thread *td)
|
|
{
|
|
/*
|
|
* XXX we cheat slightly on the locking here to avoid locking in
|
|
* the usual case. Setting td_priority here is essentially an
|
|
* incomplete workaround for not setting it properly elsewhere.
|
|
* Now that some interrupt handlers are threads, not setting it
|
|
* properly elsewhere can clobber it in the window between setting
|
|
* it here and returning to user mode, so don't waste time setting
|
|
* it perfectly here.
|
|
*/
|
|
KASSERT((td->td_flags & TDF_BORROWING) == 0,
|
|
("thread with borrowed priority returning to userland"));
|
|
if (td->td_priority != td->td_user_pri) {
|
|
thread_lock(td);
|
|
td->td_priority = td->td_user_pri;
|
|
td->td_base_pri = td->td_user_pri;
|
|
thread_unlock(td);
|
|
}
|
|
}
|
|
|
|
void
|
|
sched_bind(struct thread *td, int cpu)
|
|
{
|
|
struct td_sched *ts;
|
|
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
KASSERT(TD_IS_RUNNING(td),
|
|
("sched_bind: cannot bind non-running thread"));
|
|
|
|
ts = td->td_sched;
|
|
|
|
ts->ts_flags |= TSF_BOUND;
|
|
#ifdef SMP
|
|
ts->ts_runq = &runq_pcpu[cpu];
|
|
if (PCPU_GET(cpuid) == cpu)
|
|
return;
|
|
|
|
mi_switch(SW_VOL, NULL);
|
|
#endif
|
|
}
|
|
|
|
void
|
|
sched_unbind(struct thread* td)
|
|
{
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
td->td_sched->ts_flags &= ~TSF_BOUND;
|
|
}
|
|
|
|
int
|
|
sched_is_bound(struct thread *td)
|
|
{
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
return (td->td_sched->ts_flags & TSF_BOUND);
|
|
}
|
|
|
|
void
|
|
sched_relinquish(struct thread *td)
|
|
{
|
|
thread_lock(td);
|
|
if (td->td_pri_class == PRI_TIMESHARE)
|
|
sched_prio(td, PRI_MAX_TIMESHARE);
|
|
SCHED_STAT_INC(switch_relinquish);
|
|
mi_switch(SW_VOL, NULL);
|
|
thread_unlock(td);
|
|
}
|
|
|
|
int
|
|
sched_load(void)
|
|
{
|
|
return (sched_tdcnt);
|
|
}
|
|
|
|
int
|
|
sched_sizeof_proc(void)
|
|
{
|
|
return (sizeof(struct proc));
|
|
}
|
|
|
|
int
|
|
sched_sizeof_thread(void)
|
|
{
|
|
return (sizeof(struct thread) + sizeof(struct td_sched));
|
|
}
|
|
|
|
fixpt_t
|
|
sched_pctcpu(struct thread *td)
|
|
{
|
|
struct td_sched *ts;
|
|
|
|
ts = td->td_sched;
|
|
return (ts->ts_pctcpu);
|
|
}
|
|
|
|
void
|
|
sched_tick(void)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* The actual idle process.
|
|
*/
|
|
void
|
|
sched_idletd(void *dummy)
|
|
{
|
|
struct proc *p;
|
|
struct thread *td;
|
|
|
|
td = curthread;
|
|
p = td->td_proc;
|
|
for (;;) {
|
|
mtx_assert(&Giant, MA_NOTOWNED);
|
|
|
|
while (sched_runnable() == 0)
|
|
cpu_idle();
|
|
|
|
mtx_lock_spin(&sched_lock);
|
|
mi_switch(SW_VOL, NULL);
|
|
mtx_unlock_spin(&sched_lock);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* A CPU is entering for the first time or a thread is exiting.
|
|
*/
|
|
void
|
|
sched_throw(struct thread *td)
|
|
{
|
|
/*
|
|
* Correct spinlock nesting. The idle thread context that we are
|
|
* borrowing was created so that it would start out with a single
|
|
* spin lock (sched_lock) held in fork_trampoline(). Since we've
|
|
* explicitly acquired locks in this function, the nesting count
|
|
* is now 2 rather than 1. Since we are nested, calling
|
|
* spinlock_exit() will simply adjust the counts without allowing
|
|
* spin lock using code to interrupt us.
|
|
*/
|
|
if (td == NULL) {
|
|
mtx_lock_spin(&sched_lock);
|
|
spinlock_exit();
|
|
} else {
|
|
MPASS(td->td_lock == &sched_lock);
|
|
}
|
|
mtx_assert(&sched_lock, MA_OWNED);
|
|
KASSERT(curthread->td_md.md_spinlock_count == 1, ("invalid count"));
|
|
PCPU_SET(switchtime, cpu_ticks());
|
|
PCPU_SET(switchticks, ticks);
|
|
cpu_throw(td, choosethread()); /* doesn't return */
|
|
}
|
|
|
|
void
|
|
sched_fork_exit(struct thread *td)
|
|
{
|
|
|
|
/*
|
|
* Finish setting up thread glue so that it begins execution in a
|
|
* non-nested critical section with sched_lock held but not recursed.
|
|
*/
|
|
td->td_oncpu = PCPU_GET(cpuid);
|
|
sched_lock.mtx_lock = (uintptr_t)td;
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED | MA_NOTRECURSED);
|
|
}
|
|
|
|
#define KERN_SWITCH_INCLUDE 1
|
|
#include "kern/kern_switch.c"
|