threads.c revision 1.15.2.2
1 1.15.2.2 yamt /* $NetBSD: threads.c,v 1.15.2.2 2014/05/22 11:41:15 yamt Exp $ */ 2 1.1 pooka 3 1.1 pooka /* 4 1.1 pooka * Copyright (c) 2007-2009 Antti Kantee. All Rights Reserved. 5 1.1 pooka * 6 1.1 pooka * Development of this software was supported by 7 1.1 pooka * The Finnish Cultural Foundation. 8 1.1 pooka * 9 1.1 pooka * Redistribution and use in source and binary forms, with or without 10 1.1 pooka * modification, are permitted provided that the following conditions 11 1.1 pooka * are met: 12 1.1 pooka * 1. Redistributions of source code must retain the above copyright 13 1.1 pooka * notice, this list of conditions and the following disclaimer. 14 1.1 pooka * 2. Redistributions in binary form must reproduce the above copyright 15 1.1 pooka * notice, this list of conditions and the following disclaimer in the 16 1.1 pooka * documentation and/or other materials provided with the distribution. 17 1.1 pooka * 18 1.1 pooka * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 19 1.1 pooka * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 20 1.1 pooka * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 21 1.1 pooka * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 1.1 pooka * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 1.1 pooka * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 24 1.1 pooka * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 1.1 pooka * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 1.1 pooka * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 1.1 pooka * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 1.1 pooka * SUCH DAMAGE. 29 1.1 pooka */ 30 1.1 pooka 31 1.1 pooka #include <sys/cdefs.h> 32 1.15.2.2 yamt __KERNEL_RCSID(0, "$NetBSD: threads.c,v 1.15.2.2 2014/05/22 11:41:15 yamt Exp $"); 33 1.1 pooka 34 1.1 pooka #include <sys/param.h> 35 1.10 pooka #include <sys/atomic.h> 36 1.1 pooka #include <sys/kmem.h> 37 1.1 pooka #include <sys/kthread.h> 38 1.11 pooka #include <sys/malloc.h> 39 1.1 pooka #include <sys/systm.h> 40 1.15.2.2 yamt #include <sys/queue.h> 41 1.1 pooka 42 1.1 pooka #include <rump/rumpuser.h> 43 1.1 pooka 44 1.1 pooka #include "rump_private.h" 45 1.1 pooka 46 1.15.2.2 yamt struct thrdesc { 47 1.1 pooka void (*f)(void *); 48 1.1 pooka void *arg; 49 1.15.2.2 yamt struct lwp *newlwp; 50 1.15.2.2 yamt int runnable; 51 1.15.2.2 yamt 52 1.15.2.2 yamt TAILQ_ENTRY(thrdesc) entries; 53 1.1 pooka }; 54 1.1 pooka 55 1.15.2.2 yamt static bool threads_are_go; 56 1.15.2.2 yamt static struct rumpuser_mtx *thrmtx; 57 1.15.2.2 yamt static struct rumpuser_cv *thrcv; 58 1.15.2.2 yamt static TAILQ_HEAD(, thrdesc) newthr; 59 1.15.2.2 yamt 60 1.1 pooka static void * 61 1.1 pooka threadbouncer(void *arg) 62 1.1 pooka { 63 1.15.2.2 yamt struct thrdesc *td = arg; 64 1.15.2.2 yamt struct lwp *l = td->newlwp; 65 1.1 pooka void (*f)(void *); 66 1.1 pooka void *thrarg; 67 1.1 pooka 68 1.15.2.2 yamt f = td->f; 69 1.15.2.2 yamt thrarg = td->arg; 70 1.15.2.2 yamt 71 1.15.2.2 yamt /* don't allow threads to run before all CPUs have fully attached */ 72 1.15.2.2 yamt if (!threads_are_go) { 73 1.15.2.2 yamt rumpuser_mutex_enter_nowrap(thrmtx); 74 1.15.2.2 yamt while (!threads_are_go) { 75 1.15.2.2 yamt rumpuser_cv_wait_nowrap(thrcv, thrmtx); 76 1.15.2.2 yamt } 77 1.15.2.2 yamt rumpuser_mutex_exit(thrmtx); 78 1.15.2.2 yamt } 79 1.2 pooka 80 1.3 pooka /* schedule ourselves */ 81 1.15.2.2 yamt rump_lwproc_curlwp_set(l); 82 1.1 pooka rump_schedule(); 83 1.1 pooka 84 1.11 pooka /* free dance struct */ 85 1.15.2.2 yamt kmem_intr_free(td, sizeof(*td)); 86 1.11 pooka 87 1.1 pooka if ((curlwp->l_pflag & LP_MPSAFE) == 0) 88 1.1 pooka KERNEL_LOCK(1, NULL); 89 1.1 pooka 90 1.1 pooka f(thrarg); 91 1.1 pooka 92 1.1 pooka panic("unreachable, should kthread_exit()"); 93 1.1 pooka } 94 1.1 pooka 95 1.15.2.2 yamt void 96 1.15.2.2 yamt rump_thread_init(void) 97 1.15.2.2 yamt { 98 1.15.2.2 yamt 99 1.15.2.2 yamt rumpuser_mutex_init(&thrmtx, RUMPUSER_MTX_SPIN); 100 1.15.2.2 yamt rumpuser_cv_init(&thrcv); 101 1.15.2.2 yamt TAILQ_INIT(&newthr); 102 1.15.2.2 yamt } 103 1.15.2.2 yamt 104 1.15.2.2 yamt void 105 1.15.2.2 yamt rump_thread_allow(struct lwp *l) 106 1.15.2.2 yamt { 107 1.15.2.2 yamt struct thrdesc *td; 108 1.15.2.2 yamt 109 1.15.2.2 yamt rumpuser_mutex_enter(thrmtx); 110 1.15.2.2 yamt if (l == NULL) { 111 1.15.2.2 yamt threads_are_go = true; 112 1.15.2.2 yamt } else { 113 1.15.2.2 yamt TAILQ_FOREACH(td, &newthr, entries) { 114 1.15.2.2 yamt if (td->newlwp == l) { 115 1.15.2.2 yamt td->runnable = 1; 116 1.15.2.2 yamt break; 117 1.15.2.2 yamt } 118 1.15.2.2 yamt } 119 1.15.2.2 yamt } 120 1.15.2.2 yamt rumpuser_cv_broadcast(thrcv); 121 1.15.2.2 yamt rumpuser_mutex_exit(thrmtx); 122 1.15.2.2 yamt } 123 1.15.2.2 yamt 124 1.15.2.1 yamt static struct { 125 1.15.2.1 yamt const char *t_name; 126 1.15.2.1 yamt bool t_ncmp; 127 1.15.2.1 yamt } nothreads[] = { 128 1.15.2.1 yamt { "vrele", false }, 129 1.15.2.1 yamt { "vdrain", false }, 130 1.15.2.1 yamt { "cachegc", false }, 131 1.15.2.1 yamt { "nfssilly", false }, 132 1.15.2.1 yamt { "unpgc", false }, 133 1.15.2.1 yamt { "pmf", true }, 134 1.15.2.1 yamt { "xcall", true }, 135 1.15.2.1 yamt }; 136 1.15.2.1 yamt 137 1.1 pooka int 138 1.1 pooka kthread_create(pri_t pri, int flags, struct cpu_info *ci, 139 1.1 pooka void (*func)(void *), void *arg, lwp_t **newlp, const char *fmt, ...) 140 1.1 pooka { 141 1.1 pooka char thrstore[MAXCOMLEN]; 142 1.1 pooka const char *thrname = NULL; 143 1.1 pooka va_list ap; 144 1.15.2.2 yamt struct thrdesc *td; 145 1.1 pooka struct lwp *l; 146 1.1 pooka int rv; 147 1.1 pooka 148 1.1 pooka thrstore[0] = '\0'; 149 1.1 pooka if (fmt) { 150 1.1 pooka va_start(ap, fmt); 151 1.1 pooka vsnprintf(thrstore, sizeof(thrstore), fmt, ap); 152 1.1 pooka va_end(ap); 153 1.1 pooka thrname = thrstore; 154 1.1 pooka } 155 1.1 pooka 156 1.1 pooka /* 157 1.1 pooka * We don't want a module unload thread. 158 1.1 pooka * (XXX: yes, this is a kludge too, and the kernel should 159 1.1 pooka * have a more flexible method for configuring which threads 160 1.1 pooka * we want). 161 1.1 pooka */ 162 1.1 pooka if (strcmp(thrstore, "modunload") == 0) { 163 1.1 pooka return 0; 164 1.1 pooka } 165 1.1 pooka 166 1.1 pooka if (!rump_threads) { 167 1.15.2.1 yamt bool matched; 168 1.15.2.1 yamt int i; 169 1.15.2.1 yamt 170 1.15.2.1 yamt /* do we want to fake it? */ 171 1.15.2.1 yamt for (i = 0; i < __arraycount(nothreads); i++) { 172 1.15.2.1 yamt if (nothreads[i].t_ncmp) { 173 1.15.2.1 yamt matched = strncmp(thrstore, nothreads[i].t_name, 174 1.15.2.1 yamt strlen(nothreads[i].t_name)) == 0; 175 1.15.2.1 yamt } else { 176 1.15.2.1 yamt matched = strcmp(thrstore, 177 1.15.2.1 yamt nothreads[i].t_name) == 0; 178 1.15.2.1 yamt } 179 1.15.2.1 yamt if (matched) { 180 1.15.2.1 yamt aprint_error("rump kernel threads not enabled, " 181 1.15.2.1 yamt "%s not functional\n", nothreads[i].t_name); 182 1.15.2.1 yamt return 0; 183 1.15.2.1 yamt } 184 1.15.2.1 yamt } 185 1.15.2.1 yamt panic("threads not available"); 186 1.1 pooka } 187 1.1 pooka KASSERT(fmt != NULL); 188 1.1 pooka 189 1.15.2.2 yamt /* 190 1.15.2.2 yamt * Allocate with intr-safe allocator, give that we may be 191 1.15.2.2 yamt * creating interrupt threads. 192 1.15.2.2 yamt */ 193 1.15.2.2 yamt td = kmem_intr_alloc(sizeof(*td), KM_SLEEP); 194 1.15.2.2 yamt td->f = func; 195 1.15.2.2 yamt td->arg = arg; 196 1.15.2.2 yamt td->newlwp = l = rump__lwproc_alloclwp(&proc0); 197 1.9 pooka l->l_flag |= LW_SYSTEM; 198 1.1 pooka if (flags & KTHREAD_MPSAFE) 199 1.1 pooka l->l_pflag |= LP_MPSAFE; 200 1.2 pooka if (flags & KTHREAD_INTR) 201 1.2 pooka l->l_pflag |= LP_INTR; 202 1.4 pooka if (ci) { 203 1.4 pooka l->l_pflag |= LP_BOUND; 204 1.9 pooka l->l_target_cpu = ci; 205 1.4 pooka } 206 1.8 pooka if (thrname) { 207 1.8 pooka l->l_name = kmem_alloc(MAXCOMLEN, KM_SLEEP); 208 1.8 pooka strlcpy(l->l_name, thrname, MAXCOMLEN); 209 1.8 pooka } 210 1.8 pooka 211 1.15.2.2 yamt rv = rumpuser_thread_create(threadbouncer, td, thrname, 212 1.15.2.2 yamt (flags & KTHREAD_MUSTJOIN) == KTHREAD_MUSTJOIN, 213 1.15.2.2 yamt pri, ci ? ci->ci_index : -1, &l->l_ctxlink); 214 1.1 pooka if (rv) 215 1.15.2.2 yamt return rv; /* XXX */ 216 1.1 pooka 217 1.10 pooka if (newlp) { 218 1.1 pooka *newlp = l; 219 1.10 pooka } else { 220 1.15 rmind KASSERT((flags & KTHREAD_MUSTJOIN) == 0); 221 1.10 pooka } 222 1.10 pooka 223 1.1 pooka return 0; 224 1.1 pooka } 225 1.1 pooka 226 1.1 pooka void 227 1.1 pooka kthread_exit(int ecode) 228 1.1 pooka { 229 1.1 pooka 230 1.1 pooka if ((curlwp->l_pflag & LP_MPSAFE) == 0) 231 1.6 pooka KERNEL_UNLOCK_LAST(NULL); 232 1.12 pooka rump_lwproc_releaselwp(); 233 1.10 pooka /* unschedule includes membar */ 234 1.1 pooka rump_unschedule(); 235 1.1 pooka rumpuser_thread_exit(); 236 1.1 pooka } 237 1.10 pooka 238 1.10 pooka int 239 1.10 pooka kthread_join(struct lwp *l) 240 1.10 pooka { 241 1.10 pooka int rv; 242 1.10 pooka 243 1.10 pooka KASSERT(l->l_ctxlink != NULL); 244 1.10 pooka rv = rumpuser_thread_join(l->l_ctxlink); 245 1.10 pooka membar_consumer(); 246 1.10 pooka 247 1.10 pooka return rv; 248 1.10 pooka } 249 1.15.2.2 yamt 250 1.15.2.2 yamt /* 251 1.15.2.2 yamt * Create a non-kernel thread that is scheduled by a rump kernel hypercall. 252 1.15.2.2 yamt * 253 1.15.2.2 yamt * Sounds strange and out-of-place? yup yup yup. the original motivation 254 1.15.2.2 yamt * for this was aio. This is a very infrequent code path in rump kernels. 255 1.15.2.2 yamt * XXX: threads created with lwp_create() are eternal for local clients. 256 1.15.2.2 yamt * however, they are correctly reaped for remote clients with process exit. 257 1.15.2.2 yamt */ 258 1.15.2.2 yamt static void * 259 1.15.2.2 yamt lwpbouncer(void *arg) 260 1.15.2.2 yamt { 261 1.15.2.2 yamt struct thrdesc *td = arg; 262 1.15.2.2 yamt struct lwp *l = td->newlwp; 263 1.15.2.2 yamt void (*f)(void *); 264 1.15.2.2 yamt void *thrarg; 265 1.15.2.2 yamt int run; 266 1.15.2.2 yamt 267 1.15.2.2 yamt f = td->f; 268 1.15.2.2 yamt thrarg = td->arg; 269 1.15.2.2 yamt 270 1.15.2.2 yamt /* do not run until we've been enqueued */ 271 1.15.2.2 yamt rumpuser_mutex_enter_nowrap(thrmtx); 272 1.15.2.2 yamt while ((run = td->runnable) == 0) { 273 1.15.2.2 yamt rumpuser_cv_wait_nowrap(thrcv, thrmtx); 274 1.15.2.2 yamt } 275 1.15.2.2 yamt rumpuser_mutex_exit(thrmtx); 276 1.15.2.2 yamt 277 1.15.2.2 yamt /* schedule ourselves */ 278 1.15.2.2 yamt rump_lwproc_curlwp_set(l); 279 1.15.2.2 yamt rump_schedule(); 280 1.15.2.2 yamt kmem_free(td, sizeof(*td)); 281 1.15.2.2 yamt 282 1.15.2.2 yamt /* should we just die instead? */ 283 1.15.2.2 yamt if (run == -1) { 284 1.15.2.2 yamt rump_lwproc_releaselwp(); 285 1.15.2.2 yamt lwp_userret(l); 286 1.15.2.2 yamt panic("lwpbouncer reached unreachable"); 287 1.15.2.2 yamt } 288 1.15.2.2 yamt 289 1.15.2.2 yamt /* run, and don't come back! */ 290 1.15.2.2 yamt f(thrarg); 291 1.15.2.2 yamt panic("lwp return from worker not supported"); 292 1.15.2.2 yamt } 293 1.15.2.2 yamt 294 1.15.2.2 yamt int 295 1.15.2.2 yamt lwp_create(struct lwp *l1, struct proc *p2, vaddr_t uaddr, int flags, 296 1.15.2.2 yamt void *stack, size_t stacksize, void (*func)(void *), void *arg, 297 1.15.2.2 yamt struct lwp **newlwpp, int sclass) 298 1.15.2.2 yamt { 299 1.15.2.2 yamt struct thrdesc *td; 300 1.15.2.2 yamt struct lwp *l; 301 1.15.2.2 yamt int rv; 302 1.15.2.2 yamt 303 1.15.2.2 yamt if (flags) 304 1.15.2.2 yamt panic("lwp_create: flags not supported by this implementation"); 305 1.15.2.2 yamt td = kmem_alloc(sizeof(*td), KM_SLEEP); 306 1.15.2.2 yamt td->f = func; 307 1.15.2.2 yamt td->arg = arg; 308 1.15.2.2 yamt td->runnable = 0; 309 1.15.2.2 yamt td->newlwp = l = rump__lwproc_alloclwp(p2); 310 1.15.2.2 yamt 311 1.15.2.2 yamt rumpuser_mutex_enter_nowrap(thrmtx); 312 1.15.2.2 yamt TAILQ_INSERT_TAIL(&newthr, td, entries); 313 1.15.2.2 yamt rumpuser_mutex_exit(thrmtx); 314 1.15.2.2 yamt 315 1.15.2.2 yamt rv = rumpuser_thread_create(lwpbouncer, td, p2->p_comm, 0, 316 1.15.2.2 yamt PRI_USER, -1, NULL); 317 1.15.2.2 yamt if (rv) 318 1.15.2.2 yamt panic("rumpuser_thread_create failed"); /* XXX */ 319 1.15.2.2 yamt 320 1.15.2.2 yamt *newlwpp = l; 321 1.15.2.2 yamt return 0; 322 1.15.2.2 yamt } 323 1.15.2.2 yamt 324 1.15.2.2 yamt void 325 1.15.2.2 yamt lwp_exit(struct lwp *l) 326 1.15.2.2 yamt { 327 1.15.2.2 yamt struct thrdesc *td; 328 1.15.2.2 yamt 329 1.15.2.2 yamt rumpuser_mutex_enter_nowrap(thrmtx); 330 1.15.2.2 yamt TAILQ_FOREACH(td, &newthr, entries) { 331 1.15.2.2 yamt if (td->newlwp == l) { 332 1.15.2.2 yamt td->runnable = -1; 333 1.15.2.2 yamt break; 334 1.15.2.2 yamt } 335 1.15.2.2 yamt } 336 1.15.2.2 yamt rumpuser_mutex_exit(thrmtx); 337 1.15.2.2 yamt 338 1.15.2.2 yamt if (td == NULL) 339 1.15.2.2 yamt panic("lwp_exit: could not find %p\n", l); 340 1.15.2.2 yamt } 341 1.15.2.2 yamt 342 1.15.2.2 yamt void 343 1.15.2.2 yamt lwp_userret(struct lwp *l) 344 1.15.2.2 yamt { 345 1.15.2.2 yamt 346 1.15.2.2 yamt if ((l->l_flag & LW_RUMP_QEXIT) == 0) 347 1.15.2.2 yamt return; 348 1.15.2.2 yamt 349 1.15.2.2 yamt /* ok, so we should die */ 350 1.15.2.2 yamt rump_unschedule(); 351 1.15.2.2 yamt rumpuser_thread_exit(); 352 1.15.2.2 yamt } 353
Indexes created Tue Sep 30 07:10:03 GMT 2025