kern_thr.c revision 134886
1/* 2 * Copyright (c) 2003, Jeffrey Roberson <jeff@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/sys/kern/kern_thr.c 134886 2004-09-07 06:33:39Z julian $"); 29 30#include <sys/param.h> 31#include <sys/kernel.h> 32#include <sys/lock.h> 33#include <sys/mutex.h> 34#include <sys/proc.h> 35#include <sys/resourcevar.h> 36#include <sys/sched.h> 37#include <sys/sysctl.h> 38#include <sys/smp.h> 39#include <sys/sysent.h> 40#include <sys/systm.h> 41#include <sys/sysproto.h> 42#include <sys/signalvar.h> 43#include <sys/ucontext.h> 44#include <sys/thr.h> 45 46#include <machine/frame.h> 47 48extern int max_threads_per_proc; 49extern int max_groups_per_proc; 50 51SYSCTL_DECL(_kern_threads); 52static int thr_scope_sys = 0; 53SYSCTL_INT(_kern_threads, OID_AUTO, thr_scope_sys, CTLFLAG_RW, 54 &thr_scope_sys, 0, "sys or proc scope scheduling"); 55 56static int thr_concurency = 0; 57SYSCTL_INT(_kern_threads, OID_AUTO, thr_concurrency, CTLFLAG_RW, 58 &thr_concurrency, 0, "a concurrency value if not default"); 59 60/* 61 * Back end support functions. 62 */ 63 64#define RANGEOF(type, start, end) (offsetof(type, end) - offsetof(type, start)) 65 66/* 67 * System call interface. 68 */ 69int 70thr_create(struct thread *td, struct thr_create_args *uap) 71 /* ucontext_t *ctx, long *id, int flags */ 72{ 73 struct thread *newtd; 74 ucontext_t ctx; 75 long id; 76 int error; 77 struct ksegrp *kg, *newkg; 78 struct proc *p; 79 80 p = td->td_proc; 81 kg = td->td_ksegrp; 82 if ((error = copyin(uap->ctx, &ctx, sizeof(ctx)))) 83 return (error); 84 85 /* Have race condition but it is cheap */ 86 if ((p->p_numksegrps >= max_groups_per_proc) || 87 (p->p_numthreads >= max_threads_per_proc)) { 88 return (EPROCLIM); 89 } 90 /* Initialize our td and new ksegrp.. */ 91 newtd = thread_alloc(); 92 if (thr_scope_sys) 93 newkg = ksegrp_alloc(); 94 else 95 newkg = kg; 96 /* 97 * Try the copyout as soon as we allocate the td so we don't have to 98 * tear things down in a failure case below. 99 */ 100 id = newtd->td_tid; 101 if ((error = copyout(&id, uap->id, sizeof(long)))) { 102 if (thr_scope_sys) 103 ksegrp_free(newkg); 104 thread_free(newtd); 105 return (error); 106 } 107 108 bzero(&newtd->td_startzero, 109 (unsigned) RANGEOF(struct thread, td_startzero, td_endzero)); 110 bcopy(&td->td_startcopy, &newtd->td_startcopy, 111 (unsigned) RANGEOF(struct thread, td_startcopy, td_endcopy)); 112 113 if (thr_scope_sys) { 114 bzero(&newkg->kg_startzero, 115 (unsigned)RANGEOF(struct ksegrp, kg_startzero, kg_endzero)); 116 bcopy(&kg->kg_startcopy, &newkg->kg_startcopy, 117 (unsigned)RANGEOF(struct ksegrp, kg_startcopy, kg_endcopy)); 118 } 119 120 newtd->td_proc = td->td_proc; 121 newtd->td_ucred = crhold(td->td_ucred); 122 123 /* Set up our machine context. */ 124 cpu_set_upcall(newtd, td); 125 error = set_mcontext(newtd, &ctx.uc_mcontext); 126 if (error != 0) { 127 if (thr_scope_sys) 128 ksegrp_free(newkg); 129 thread_free(newtd); 130 crfree(td->td_ucred); 131 goto out; 132 } 133 134 /* Link the thread and kse into the ksegrp and make it runnable. */ 135 PROC_LOCK(td->td_proc); 136 if (thr_scope_sys) { 137 sched_init_concurrency(newkg); 138 } else { 139 if ((td->td_proc->p_flag & P_HADTHREADS) == 0) { 140 sched_set_concurrency(kg, 141 thr_concurrency ? thr_concurrency : (2*mp_ncpus)); 142 } 143 } 144 145 td->td_proc->p_flag |= P_HADTHREADS; 146 newtd->td_sigmask = td->td_sigmask; 147 mtx_lock_spin(&sched_lock); 148 if (thr_scope_sys) 149 ksegrp_link(newkg, p); 150 thread_link(newtd, newkg); 151 mtx_unlock_spin(&sched_lock); 152 PROC_UNLOCK(p); 153 154 /* let the scheduler know about these things. */ 155 mtx_lock_spin(&sched_lock); 156 if (thr_scope_sys) 157 sched_fork_ksegrp(td, newkg); 158 sched_fork_thread(td, newtd); 159 160 TD_SET_CAN_RUN(newtd); 161 if ((uap->flags & THR_SUSPENDED) == 0) 162 setrunqueue(newtd, SRQ_BORING); 163 164 mtx_unlock_spin(&sched_lock); 165 166out: 167 return (error); 168} 169 170int 171thr_self(struct thread *td, struct thr_self_args *uap) 172 /* long *id */ 173{ 174 long id; 175 int error; 176 177 id = td->td_tid; 178 if ((error = copyout(&id, uap->id, sizeof(long)))) 179 return (error); 180 181 return (0); 182} 183 184int 185thr_exit(struct thread *td, struct thr_exit_args *uap) 186 /* NULL */ 187{ 188 struct proc *p; 189 190 p = td->td_proc; 191 192 PROC_LOCK(p); 193 mtx_lock_spin(&sched_lock); 194 195 /* 196 * Shutting down last thread in the proc. This will actually 197 * call exit() in the trampoline when it returns. 198 */ 199 if (p->p_numthreads != 1) { 200 thread_exit(); 201 /* NOTREACHED */ 202 } 203 mtx_unlock_spin(&sched_lock); 204 PROC_UNLOCK(p); 205 return (0); 206} 207 208int 209thr_kill(struct thread *td, struct thr_kill_args *uap) 210 /* long id, int sig */ 211{ 212 struct thread *ttd; 213 struct proc *p; 214 int error; 215 216 p = td->td_proc; 217 error = 0; 218 PROC_LOCK(p); 219 FOREACH_THREAD_IN_PROC(p, ttd) { 220 if (ttd->td_tid == uap->id) 221 break; 222 } 223 if (ttd == NULL) { 224 error = ESRCH; 225 goto out; 226 } 227 if (uap->sig == 0) 228 goto out; 229 if (!_SIG_VALID(uap->sig)) { 230 error = EINVAL; 231 goto out; 232 } 233 tdsignal(ttd, uap->sig, SIGTARGET_TD); 234out: 235 PROC_UNLOCK(p); 236 return (error); 237} 238 239int 240thr_suspend(struct thread *td, struct thr_suspend_args *uap) 241 /* const struct timespec *timeout */ 242{ 243 struct timespec ts; 244 struct timeval tv; 245 int error; 246 int hz; 247 248 hz = 0; 249 error = 0; 250 if (uap->timeout != NULL) { 251 error = copyin((const void *)uap->timeout, (void *)&ts, 252 sizeof(struct timespec)); 253 if (error != 0) 254 return (error); 255 if (ts.tv_nsec < 0 || ts.tv_nsec > 1000000000) 256 return (EINVAL); 257 if (ts.tv_sec == 0 && ts.tv_nsec == 0) 258 return (ETIMEDOUT); 259 TIMESPEC_TO_TIMEVAL(&tv, &ts); 260 hz = tvtohz(&tv); 261 } 262 PROC_LOCK(td->td_proc); 263 if ((td->td_flags & TDF_THRWAKEUP) == 0) 264 error = msleep((void *)td, &td->td_proc->p_mtx, 265 td->td_priority | PCATCH, "lthr", hz); 266 mtx_lock_spin(&sched_lock); 267 td->td_flags &= ~TDF_THRWAKEUP; 268 mtx_unlock_spin(&sched_lock); 269 PROC_UNLOCK(td->td_proc); 270 return (error == EWOULDBLOCK ? ETIMEDOUT : error); 271} 272 273int 274thr_wake(struct thread *td, struct thr_wake_args *uap) 275 /* long id */ 276{ 277 struct thread *ttd; 278 279 PROC_LOCK(td->td_proc); 280 FOREACH_THREAD_IN_PROC(td->td_proc, ttd) { 281 if (ttd->td_tid == uap->id) 282 break; 283 } 284 if (ttd == NULL) { 285 PROC_UNLOCK(td->td_proc); 286 return (ESRCH); 287 } 288 mtx_lock_spin(&sched_lock); 289 ttd->td_flags |= TDF_THRWAKEUP; 290 mtx_unlock_spin(&sched_lock); 291 wakeup_one((void *)ttd); 292 PROC_UNLOCK(td->td_proc); 293 return (0); 294} 295