1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 /* 27 * Copyright 2018 Joyent, Inc. 28 */ 29 30 #include "lint.h" 31 #include "thr_uberdata.h" 32 33 /* 34 * pthread_once related data 35 * This structure is exported as pthread_once_t in pthread.h. 36 * We export only the size of this structure. so check 37 * pthread_once_t in pthread.h before making a change here. 38 */ 39 typedef struct __once { 40 mutex_t mlock; 41 union { 42 uint32_t pad32_flag[2]; 43 uint64_t pad64_flag; 44 } oflag; 45 } __once_t; 46 47 #define once_flag oflag.pad32_flag[1] 48 49 static int 50 _thr_setinherit(pthread_t tid, int inherit) 51 { 52 ulwp_t *ulwp; 53 int error = 0; 54 55 if ((ulwp = find_lwp(tid)) == NULL) { 56 error = ESRCH; 57 } else { 58 ulwp->ul_ptinherit = inherit; 59 ulwp_unlock(ulwp, curthread->ul_uberdata); 60 } 61 62 return (error); 63 } 64 65 static int 66 _thr_setparam(pthread_t tid, int policy, int prio) 67 { 68 ulwp_t *ulwp; 69 id_t cid; 70 int error = 0; 71 72 if ((ulwp = find_lwp(tid)) == NULL) { 73 error = ESRCH; 74 } else { 75 if (policy == ulwp->ul_policy && 76 (policy == SCHED_FIFO || policy == SCHED_RR) && 77 ulwp->ul_epri != 0) { 78 /* 79 * Don't change the ceiling priority, 80 * just the base priority. 81 */ 82 if (prio > ulwp->ul_epri) 83 error = EPERM; 84 else 85 ulwp->ul_pri = prio; 86 } else if ((cid = setparam(P_LWPID, tid, policy, prio)) == -1) { 87 error = errno; 88 } else { 89 if (policy == SCHED_FIFO || policy == SCHED_RR) 90 ulwp->ul_rtclassid = cid; 91 ulwp->ul_cid = cid; 92 ulwp->ul_pri = prio; 93 membar_producer(); 94 ulwp->ul_policy = policy; 95 } 96 ulwp_unlock(ulwp, curthread->ul_uberdata); 97 } 98 return (error); 99 } 100 101 /* 102 * pthread_create: creates a thread in the current process. 103 * calls common _thrp_create() after copying the attributes. 104 */ 105 #pragma weak _pthread_create = pthread_create 106 int 107 pthread_create(pthread_t *thread, const pthread_attr_t *attr, 108 void * (*start_routine)(void *), void *arg) 109 { 110 ulwp_t *self = curthread; 111 const thrattr_t *ap = attr? attr->__pthread_attrp : def_thrattr(); 112 const pcclass_t *pccp; 113 long flag; 114 pthread_t tid; 115 int error; 116 117 update_sched(self); 118 119 if (ap == NULL) 120 return (EINVAL); 121 122 /* validate explicit scheduling attributes */ 123 if (ap->inherit == PTHREAD_EXPLICIT_SCHED && 124 (ap->policy == SCHED_SYS || 125 (pccp = get_info_by_policy(ap->policy)) == NULL || 126 ap->prio < pccp->pcc_primin || ap->prio > pccp->pcc_primax)) 127 return (EINVAL); 128 129 flag = ap->scope | ap->detachstate | ap->daemonstate | THR_SUSPENDED; 130 error = _thrp_create(ap->stkaddr, ap->stksize, start_routine, arg, 131 flag, &tid, ap->guardsize, ap->name); 132 if (error == 0) { 133 /* 134 * Record the original inheritence value for 135 * pthread_getattr_np(). We should always be able to find the 136 * thread. 137 */ 138 (void) _thr_setinherit(tid, ap->inherit); 139 140 if (ap->inherit == PTHREAD_EXPLICIT_SCHED && 141 (ap->policy != self->ul_policy || 142 ap->prio != (self->ul_epri ? self->ul_epri : 143 self->ul_pri))) { 144 /* 145 * The SUSv3 specification requires pthread_create() 146 * to fail with EPERM if it cannot set the scheduling 147 * policy and parameters on the new thread. 148 */ 149 error = _thr_setparam(tid, ap->policy, ap->prio); 150 } 151 152 if (error) { 153 /* 154 * We couldn't determine this error before 155 * actually creating the thread. To recover, 156 * mark the thread detached and cancel it. 157 * It is as though it was never created. 158 */ 159 ulwp_t *ulwp = find_lwp(tid); 160 if (ulwp->ul_detached == 0) { 161 ulwp->ul_detached = 1; 162 ulwp->ul_usropts |= THR_DETACHED; 163 (void) __lwp_detach(tid); 164 } 165 ulwp->ul_cancel_pending = 2; /* cancelled on creation */ 166 ulwp->ul_cancel_disabled = 0; 167 ulwp_unlock(ulwp, self->ul_uberdata); 168 } else if (thread) { 169 *thread = tid; 170 } 171 (void) thr_continue(tid); 172 } 173 174 /* posix version expects EAGAIN for lack of memory */ 175 if (error == ENOMEM) 176 error = EAGAIN; 177 return (error); 178 } 179 180 /* 181 * pthread_once: calls given function only once. 182 * it synchronizes via mutex in pthread_once_t structure 183 */ 184 int 185 pthread_once(pthread_once_t *once_control, void (*init_routine)(void)) 186 { 187 __once_t *once = (__once_t *)once_control; 188 189 if (once == NULL || init_routine == NULL) 190 return (EINVAL); 191 192 if (once->once_flag == PTHREAD_ONCE_NOTDONE) { 193 (void) mutex_lock(&once->mlock); 194 if (once->once_flag == PTHREAD_ONCE_NOTDONE) { 195 pthread_cleanup_push(mutex_unlock, &once->mlock); 196 (*init_routine)(); 197 pthread_cleanup_pop(0); 198 membar_producer(); 199 once->once_flag = PTHREAD_ONCE_DONE; 200 } 201 (void) mutex_unlock(&once->mlock); 202 } 203 membar_consumer(); 204 205 return (0); 206 } 207 208 /* 209 * pthread_equal: equates two thread ids. 210 */ 211 int 212 pthread_equal(pthread_t t1, pthread_t t2) 213 { 214 return (t1 == t2); 215 } 216 217 /* 218 * pthread_getschedparam: get the thread's sched parameters. 219 */ 220 #pragma weak _pthread_getschedparam = pthread_getschedparam 221 int 222 pthread_getschedparam(pthread_t tid, int *policy, struct sched_param *param) 223 { 224 ulwp_t *ulwp; 225 id_t cid; 226 int error = 0; 227 228 if ((ulwp = find_lwp(tid)) == NULL) { 229 error = ESRCH; 230 } else { 231 cid = getparam(P_LWPID, ulwp->ul_lwpid, policy, param); 232 if (cid == -1) { 233 error = errno; 234 } else if (*policy == ulwp->ul_policy && cid == ulwp->ul_cid && 235 (*policy == SCHED_FIFO || *policy == SCHED_RR)) { 236 /* 237 * Return the defined priority, not the effective 238 * priority from priority ceiling mutexes. 239 */ 240 param->sched_priority = ulwp->ul_pri; 241 } else { 242 if (*policy == SCHED_FIFO || *policy == SCHED_RR) 243 ulwp->ul_rtclassid = cid; 244 ulwp->ul_cid = cid; 245 ulwp->ul_pri = param->sched_priority; 246 membar_producer(); 247 ulwp->ul_policy = *policy; 248 } 249 ulwp_unlock(ulwp, curthread->ul_uberdata); 250 } 251 252 return (error); 253 } 254 255 #pragma weak _thr_getprio = thr_getprio 256 int 257 thr_getprio(thread_t tid, int *priority) 258 { 259 struct sched_param param; 260 int policy; 261 int error; 262 263 if ((error = pthread_getschedparam(tid, &policy, ¶m)) == 0) 264 *priority = param.sched_priority; 265 return (error); 266 } 267 268 /* 269 * pthread_setschedparam: sets the sched parameters for a thread. 270 */ 271 int 272 pthread_setschedparam(pthread_t tid, 273 int policy, const struct sched_param *param) 274 { 275 return (_thr_setparam(tid, policy, param->sched_priority)); 276 } 277 278 #pragma weak pthread_setschedprio = thr_setprio 279 int 280 thr_setprio(thread_t tid, int prio) 281 { 282 struct sched_param param; 283 int policy; 284 int error; 285 286 /* 287 * pthread_getschedparam() has the side-effect of setting 288 * the target thread's ul_policy, ul_pri and ul_cid correctly. 289 */ 290 if ((error = pthread_getschedparam(tid, &policy, ¶m)) != 0) 291 return (error); 292 if (param.sched_priority == prio) /* no change */ 293 return (0); 294 return (_thr_setparam(tid, policy, prio)); 295 } 296