1/*- 2 * SPDX-License-Identifier: (BSD-4-Clause AND BSD-2-Clause) 3 * 4 * Copyright (c) 1996, 1997 5 * HD Associates, Inc. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by HD Associates, Inc 18 * and Jukka Antero Ukkonen. 19 * 4. Neither the name of the author nor the names of any co-contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY HD ASSOCIATES AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL HD ASSOCIATES OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36/*- 37 * Copyright (c) 2002-2008, Jeffrey Roberson <jeff@freebsd.org> 38 * All rights reserved. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice unmodified, this list of conditions, and the following 45 * disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 50 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 51 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 52 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 53 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 54 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 55 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 56 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 57 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 58 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 59 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 60 */ 61 62#ifndef _SCHED_H_ 63#define _SCHED_H_ 64 65#ifdef _KERNEL 66/* 67 * General scheduling info. 68 * 69 * sched_load: 70 * Total runnable non-ithread threads in the system. 71 * 72 * sched_runnable: 73 * Runnable threads for this processor. 74 */ 75int sched_load(void); 76int sched_rr_interval(void); 77int sched_runnable(void); 78 79/* 80 * Proc related scheduling hooks. 81 */ 82void sched_exit(struct proc *p, struct thread *childtd); 83void sched_fork(struct thread *td, struct thread *childtd); 84void sched_fork_exit(struct thread *td); 85void sched_class(struct thread *td, int class); 86void sched_nice(struct proc *p, int nice); 87 88/* 89 * Threads are switched in and out, block on resources, have temporary 90 * priorities inherited from their procs, and use up cpu time. 91 */ 92void sched_ap_entry(void); 93void sched_exit_thread(struct thread *td, struct thread *child); 94u_int sched_estcpu(struct thread *td); 95void sched_fork_thread(struct thread *td, struct thread *child); 96void sched_ithread_prio(struct thread *td, u_char prio); 97void sched_lend_prio(struct thread *td, u_char prio); 98void sched_lend_user_prio(struct thread *td, u_char pri); 99void sched_lend_user_prio_cond(struct thread *td, u_char pri); 100fixpt_t sched_pctcpu(struct thread *td); 101void sched_prio(struct thread *td, u_char prio); 102void sched_sleep(struct thread *td, int prio); 103void sched_switch(struct thread *td, int flags); 104void sched_throw(struct thread *td); 105void sched_unlend_prio(struct thread *td, u_char prio); 106void sched_user_prio(struct thread *td, u_char prio); 107void sched_userret_slowpath(struct thread *td); 108#ifdef RACCT 109#ifdef SCHED_4BSD 110fixpt_t sched_pctcpu_delta(struct thread *td); 111#endif 112#endif 113 114static inline void 115sched_userret(struct thread *td) 116{ 117 118 /* 119 * XXX we cheat slightly on the locking here to avoid locking in 120 * the usual case. Setting td_priority here is essentially an 121 * incomplete workaround for not setting it properly elsewhere. 122 * Now that some interrupt handlers are threads, not setting it 123 * properly elsewhere can clobber it in the window between setting 124 * it here and returning to user mode, so don't waste time setting 125 * it perfectly here. 126 */ 127 KASSERT((td->td_flags & TDF_BORROWING) == 0, 128 ("thread with borrowed priority returning to userland")); 129 if (__predict_false(td->td_priority != td->td_user_pri)) 130 sched_userret_slowpath(td); 131} 132 133/* 134 * Threads are moved on and off of run queues 135 */ 136void sched_add(struct thread *td, int flags); 137struct thread *sched_choose(void); 138void sched_clock(struct thread *td, int cnt); 139void sched_idletd(void *); 140void sched_preempt(struct thread *td); 141void sched_relinquish(struct thread *td); 142void sched_rem(struct thread *td); 143void sched_wakeup(struct thread *td, int srqflags); 144 145/* 146 * Binding makes cpu affinity permanent while pinning is used to temporarily 147 * hold a thread on a particular CPU. 148 */ 149void sched_bind(struct thread *td, int cpu); 150static __inline void sched_pin(void); 151void sched_unbind(struct thread *td); 152static __inline void sched_unpin(void); 153int sched_is_bound(struct thread *td); 154void sched_affinity(struct thread *td); 155 156/* 157 * These procedures tell the process data structure allocation code how 158 * many bytes to actually allocate. 159 */ 160int sched_sizeof_proc(void); 161int sched_sizeof_thread(void); 162 163/* 164 * This routine provides a consistent thread name for use with KTR graphing 165 * functions. 166 */ 167char *sched_tdname(struct thread *td); 168#ifdef KTR 169void sched_clear_tdname(struct thread *td); 170#endif 171 172static __inline void 173sched_pin(void) 174{ 175 curthread->td_pinned++; 176 atomic_interrupt_fence(); 177} 178 179static __inline void 180sched_unpin(void) 181{ 182 atomic_interrupt_fence(); 183 curthread->td_pinned--; 184} 185 186/* sched_add arguments (formerly setrunqueue) */ 187#define SRQ_BORING 0x0000 /* No special circumstances. */ 188#define SRQ_YIELDING 0x0001 /* We are yielding (from mi_switch). */ 189#define SRQ_OURSELF 0x0002 /* It is ourself (from mi_switch). */ 190#define SRQ_INTR 0x0004 /* It is probably urgent. */ 191#define SRQ_PREEMPTED 0x0008 /* has been preempted.. be kind */ 192#define SRQ_BORROWING 0x0010 /* Priority updated due to prio_lend */ 193#define SRQ_HOLD 0x0020 /* Return holding original td lock */ 194#define SRQ_HOLDTD 0x0040 /* Return holding td lock */ 195 196/* Scheduler stats. */ 197#ifdef SCHED_STATS 198DPCPU_DECLARE(long, sched_switch_stats[SWT_COUNT]); 199 200#define SCHED_STAT_DEFINE_VAR(name, ptr, descr) \ 201static void name ## _add_proc(void *dummy __unused) \ 202{ \ 203 \ 204 SYSCTL_ADD_PROC(NULL, \ 205 SYSCTL_STATIC_CHILDREN(_kern_sched_stats), OID_AUTO, \ 206 #name, CTLTYPE_LONG|CTLFLAG_RD|CTLFLAG_MPSAFE, \ 207 ptr, 0, sysctl_dpcpu_long, "LU", descr); \ 208} \ 209SYSINIT(name, SI_SUB_LAST, SI_ORDER_MIDDLE, name ## _add_proc, NULL); 210 211#define SCHED_STAT_DEFINE(name, descr) \ 212 DPCPU_DEFINE(unsigned long, name); \ 213 SCHED_STAT_DEFINE_VAR(name, &DPCPU_NAME(name), descr) 214/* 215 * Sched stats are always incremented in critical sections so no atomic 216 * is necessary to increment them. 217 */ 218#define SCHED_STAT_INC(var) DPCPU_GET(var)++; 219#else 220#define SCHED_STAT_DEFINE_VAR(name, descr, ptr) 221#define SCHED_STAT_DEFINE(name, descr) 222#define SCHED_STAT_INC(var) (void)0 223#endif 224 225/* 226 * Fixup scheduler state for proc0 and thread0 227 */ 228void schedinit(void); 229 230/* 231 * Fixup scheduler state for secondary APs 232 */ 233void schedinit_ap(void); 234#endif /* _KERNEL */ 235 236/* POSIX 1003.1b Process Scheduling */ 237 238/* 239 * POSIX scheduling policies 240 */ 241#define SCHED_FIFO 1 242#define SCHED_OTHER 2 243#define SCHED_RR 3 244 245struct sched_param { 246 int sched_priority; 247}; 248 249/* 250 * POSIX scheduling declarations for userland. 251 */ 252#ifndef _KERNEL 253#include <sys/cdefs.h> 254#include <sys/_timespec.h> 255#include <sys/_types.h> 256 257#ifndef _PID_T_DECLARED 258typedef __pid_t pid_t; 259#define _PID_T_DECLARED 260#endif 261 262__BEGIN_DECLS 263int sched_get_priority_max(int); 264int sched_get_priority_min(int); 265int sched_getparam(pid_t, struct sched_param *); 266int sched_getscheduler(pid_t); 267int sched_rr_get_interval(pid_t, struct timespec *); 268int sched_setparam(pid_t, const struct sched_param *); 269int sched_setscheduler(pid_t, int, const struct sched_param *); 270int sched_yield(void); 271__END_DECLS 272 273#endif 274#endif /* !_SCHED_H_ */ 275