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 * $FreeBSD$ 62 */ 63 64 #ifndef _SCHED_H_ 65 #define _SCHED_H_ 66 67 #ifdef _KERNEL 68 /* 69 * General scheduling info. 70 * 71 * sched_load: 72 * Total runnable non-ithread threads in the system. 73 * 74 * sched_runnable: 75 * Runnable threads for this processor. 76 */ 77 int sched_load(void); 78 int sched_rr_interval(void); 79 int sched_runnable(void); 80 81 /* 82 * Proc related scheduling hooks. 83 */ 84 void sched_exit(struct proc *p, struct thread *childtd); 85 void sched_fork(struct thread *td, struct thread *childtd); 86 void sched_fork_exit(struct thread *td); 87 void sched_class(struct thread *td, int class); 88 void sched_nice(struct proc *p, int nice); 89 90 /* 91 * Threads are switched in and out, block on resources, have temporary 92 * priorities inherited from their procs, and use up cpu time. 93 */ 94 void sched_ap_entry(void); 95 void sched_exit_thread(struct thread *td, struct thread *child); 96 u_int sched_estcpu(struct thread *td); 97 void sched_fork_thread(struct thread *td, struct thread *child); 98 void sched_ithread_prio(struct thread *td, u_char prio); 99 void sched_lend_prio(struct thread *td, u_char prio); 100 void sched_lend_user_prio(struct thread *td, u_char pri); 101 void sched_lend_user_prio_cond(struct thread *td, u_char pri); 102 fixpt_t sched_pctcpu(struct thread *td); 103 void sched_prio(struct thread *td, u_char prio); 104 void sched_sleep(struct thread *td, int prio); 105 void sched_switch(struct thread *td, int flags); 106 void sched_throw(struct thread *td); 107 void sched_unlend_prio(struct thread *td, u_char prio); 108 void sched_user_prio(struct thread *td, u_char prio); 109 void sched_userret_slowpath(struct thread *td); 110 #ifdef RACCT 111 #ifdef SCHED_4BSD 112 fixpt_t sched_pctcpu_delta(struct thread *td); 113 #endif 114 #endif 115 116 static inline void 117 sched_userret(struct thread *td) 118 { 119 120 /* 121 * XXX we cheat slightly on the locking here to avoid locking in 122 * the usual case. Setting td_priority here is essentially an 123 * incomplete workaround for not setting it properly elsewhere. 124 * Now that some interrupt handlers are threads, not setting it 125 * properly elsewhere can clobber it in the window between setting 126 * it here and returning to user mode, so don't waste time setting 127 * it perfectly here. 128 */ 129 KASSERT((td->td_flags & TDF_BORROWING) == 0, 130 ("thread with borrowed priority returning to userland")); 131 if (__predict_false(td->td_priority != td->td_user_pri)) 132 sched_userret_slowpath(td); 133 } 134 135 /* 136 * Threads are moved on and off of run queues 137 */ 138 void sched_add(struct thread *td, int flags); 139 struct thread *sched_choose(void); 140 void sched_clock(struct thread *td, int cnt); 141 void sched_idletd(void *); 142 void sched_preempt(struct thread *td); 143 void sched_relinquish(struct thread *td); 144 void sched_rem(struct thread *td); 145 void sched_wakeup(struct thread *td, int srqflags); 146 147 /* 148 * Binding makes cpu affinity permanent while pinning is used to temporarily 149 * hold a thread on a particular CPU. 150 */ 151 void sched_bind(struct thread *td, int cpu); 152 static __inline void sched_pin(void); 153 void sched_unbind(struct thread *td); 154 static __inline void sched_unpin(void); 155 int sched_is_bound(struct thread *td); 156 void sched_affinity(struct thread *td); 157 158 /* 159 * These procedures tell the process data structure allocation code how 160 * many bytes to actually allocate. 161 */ 162 int sched_sizeof_proc(void); 163 int sched_sizeof_thread(void); 164 165 /* 166 * This routine provides a consistent thread name for use with KTR graphing 167 * functions. 168 */ 169 char *sched_tdname(struct thread *td); 170 #ifdef KTR 171 void sched_clear_tdname(struct thread *td); 172 #endif 173 174 static __inline void 175 sched_pin(void) 176 { 177 curthread->td_pinned++; 178 atomic_interrupt_fence(); 179 } 180 181 static __inline void 182 sched_unpin(void) 183 { 184 atomic_interrupt_fence(); 185 curthread->td_pinned--; 186 } 187 188 /* sched_add arguments (formerly setrunqueue) */ 189 #define SRQ_BORING 0x0000 /* No special circumstances. */ 190 #define SRQ_YIELDING 0x0001 /* We are yielding (from mi_switch). */ 191 #define SRQ_OURSELF 0x0002 /* It is ourself (from mi_switch). */ 192 #define SRQ_INTR 0x0004 /* It is probably urgent. */ 193 #define SRQ_PREEMPTED 0x0008 /* has been preempted.. be kind */ 194 #define SRQ_BORROWING 0x0010 /* Priority updated due to prio_lend */ 195 #define SRQ_HOLD 0x0020 /* Return holding original td lock */ 196 #define SRQ_HOLDTD 0x0040 /* Return holding td lock */ 197 198 /* Scheduler stats. */ 199 #ifdef SCHED_STATS 200 DPCPU_DECLARE(long, sched_switch_stats[SWT_COUNT]); 201 202 #define SCHED_STAT_DEFINE_VAR(name, ptr, descr) \ 203 static void name ## _add_proc(void *dummy __unused) \ 204 { \ 205 \ 206 SYSCTL_ADD_PROC(NULL, \ 207 SYSCTL_STATIC_CHILDREN(_kern_sched_stats), OID_AUTO, \ 208 #name, CTLTYPE_LONG|CTLFLAG_RD|CTLFLAG_MPSAFE, \ 209 ptr, 0, sysctl_dpcpu_long, "LU", descr); \ 210 } \ 211 SYSINIT(name, SI_SUB_LAST, SI_ORDER_MIDDLE, name ## _add_proc, NULL); 212 213 #define SCHED_STAT_DEFINE(name, descr) \ 214 DPCPU_DEFINE(unsigned long, name); \ 215 SCHED_STAT_DEFINE_VAR(name, &DPCPU_NAME(name), descr) 216 /* 217 * Sched stats are always incremented in critical sections so no atomic 218 * is necesssary to increment them. 219 */ 220 #define SCHED_STAT_INC(var) DPCPU_GET(var)++; 221 #else 222 #define SCHED_STAT_DEFINE_VAR(name, descr, ptr) 223 #define SCHED_STAT_DEFINE(name, descr) 224 #define SCHED_STAT_INC(var) (void)0 225 #endif 226 227 /* 228 * Fixup scheduler state for proc0 and thread0 229 */ 230 void schedinit(void); 231 232 /* 233 * Fixup scheduler state for secondary APs 234 */ 235 void schedinit_ap(void); 236 #endif /* _KERNEL */ 237 238 /* POSIX 1003.1b Process Scheduling */ 239 240 /* 241 * POSIX scheduling policies 242 */ 243 #define SCHED_FIFO 1 244 #define SCHED_OTHER 2 245 #define SCHED_RR 3 246 247 struct sched_param { 248 int sched_priority; 249 }; 250 251 /* 252 * POSIX scheduling declarations for userland. 253 */ 254 #ifndef _KERNEL 255 #include <sys/cdefs.h> 256 #include <sys/_timespec.h> 257 #include <sys/_types.h> 258 259 #ifndef _PID_T_DECLARED 260 typedef __pid_t pid_t; 261 #define _PID_T_DECLARED 262 #endif 263 264 __BEGIN_DECLS 265 int sched_get_priority_max(int); 266 int sched_get_priority_min(int); 267 int sched_getparam(pid_t, struct sched_param *); 268 int sched_getscheduler(pid_t); 269 int sched_rr_get_interval(pid_t, struct timespec *); 270 int sched_setparam(pid_t, const struct sched_param *); 271 int sched_setscheduler(pid_t, int, const struct sched_param *); 272 int sched_yield(void); 273 __END_DECLS 274 275 #endif 276 #endif /* !_SCHED_H_ */ 277