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 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include "lint.h" 30 #include "thr_uberdata.h" 31 32 /* 33 * pthread_once related data 34 * This structure is exported as pthread_once_t in pthread.h. 35 * We export only the size of this structure. so check 36 * pthread_once_t in pthread.h before making a change here. 37 */ 38 typedef struct __once { 39 mutex_t mlock; 40 union { 41 uint32_t pad32_flag[2]; 42 uint64_t pad64_flag; 43 } oflag; 44 } __once_t; 45 46 #define once_flag oflag.pad32_flag[1] 47 48 static int 49 _thr_setparam(pthread_t tid, int policy, int prio) 50 { 51 ulwp_t *ulwp; 52 id_t cid; 53 int error = 0; 54 55 if ((ulwp = find_lwp(tid)) == NULL) { 56 error = ESRCH; 57 } else { 58 if (policy == ulwp->ul_policy && 59 (policy == SCHED_FIFO || policy == SCHED_RR) && 60 ulwp->ul_cid == ulwp->ul_rtclassid && 61 ulwp->ul_epri != 0) { 62 /* 63 * Don't change the ceiling priority, 64 * just the base priority. 65 */ 66 if (prio > ulwp->ul_epri) 67 error = EPERM; 68 else 69 ulwp->ul_pri = prio; 70 } else if ((cid = setparam(P_LWPID, tid, policy, prio)) == -1) { 71 error = errno; 72 } else { 73 ulwp->ul_cid = cid; 74 ulwp->ul_pri = prio; 75 _membar_producer(); 76 ulwp->ul_policy = policy; 77 } 78 ulwp_unlock(ulwp, curthread->ul_uberdata); 79 } 80 return (error); 81 } 82 83 /* 84 * pthread_create: creates a thread in the current process. 85 * calls common _thrp_create() after copying the attributes. 86 */ 87 #pragma weak pthread_create = _pthread_create 88 int 89 _pthread_create(pthread_t *thread, const pthread_attr_t *attr, 90 void * (*start_routine)(void *), void *arg) 91 { 92 ulwp_t *self = curthread; 93 const thrattr_t *ap = attr? attr->__pthread_attrp : def_thrattr(); 94 const pcclass_t *pccp; 95 long flag; 96 pthread_t tid; 97 int error; 98 99 update_sched(self); 100 101 if (ap == NULL) 102 return (EINVAL); 103 104 /* validate explicit scheduling attributes */ 105 if (ap->inherit == PTHREAD_EXPLICIT_SCHED && 106 (ap->policy == SCHED_SYS || 107 (pccp = get_info_by_policy(ap->policy)) == NULL || 108 ap->prio < pccp->pcc_primin || ap->prio > pccp->pcc_primax)) 109 return (EINVAL); 110 111 flag = ap->scope | ap->detachstate | ap->daemonstate | THR_SUSPENDED; 112 error = _thrp_create(ap->stkaddr, ap->stksize, start_routine, arg, 113 flag, &tid, ap->guardsize); 114 if (error == 0) { 115 if (ap->inherit == PTHREAD_EXPLICIT_SCHED && 116 (ap->policy != self->ul_policy || 117 ap->prio != (self->ul_epri? self->ul_epri : self->ul_pri))) 118 /* 119 * The SUSv3 specification requires pthread_create() 120 * to fail with EPERM if it cannot set the scheduling 121 * policy and parameters on the new thread. 122 */ 123 error = _thr_setparam(tid, ap->policy, ap->prio); 124 if (error) { 125 /* 126 * We couldn't determine this error before 127 * actually creating the thread. To recover, 128 * mark the thread detached and cancel it. 129 * It is as though it was never created. 130 */ 131 ulwp_t *ulwp = find_lwp(tid); 132 if (ulwp->ul_detached == 0) { 133 ulwp->ul_detached = 1; 134 ulwp->ul_usropts |= THR_DETACHED; 135 (void) __lwp_detach(tid); 136 } 137 ulwp->ul_cancel_pending = 2; /* cancelled on creation */ 138 ulwp->ul_cancel_disabled = 0; 139 ulwp_unlock(ulwp, self->ul_uberdata); 140 } else if (thread) { 141 *thread = tid; 142 } 143 (void) _thr_continue(tid); 144 } 145 146 /* posix version expects EAGAIN for lack of memory */ 147 if (error == ENOMEM) 148 error = EAGAIN; 149 return (error); 150 } 151 152 /* 153 * pthread_once: calls given function only once. 154 * it synchronizes via mutex in pthread_once_t structure 155 */ 156 #pragma weak pthread_once = _pthread_once 157 int 158 _pthread_once(pthread_once_t *once_control, void (*init_routine)(void)) 159 { 160 __once_t *once = (__once_t *)once_control; 161 162 if (once == NULL || init_routine == NULL) 163 return (EINVAL); 164 165 if (once->once_flag == PTHREAD_ONCE_NOTDONE) { 166 (void) _private_mutex_lock(&once->mlock); 167 if (once->once_flag == PTHREAD_ONCE_NOTDONE) { 168 pthread_cleanup_push(_private_mutex_unlock, 169 &once->mlock); 170 (*init_routine)(); 171 pthread_cleanup_pop(0); 172 _membar_producer(); 173 once->once_flag = PTHREAD_ONCE_DONE; 174 } 175 (void) _private_mutex_unlock(&once->mlock); 176 } 177 _membar_consumer(); 178 179 return (0); 180 } 181 182 /* 183 * pthread_equal: equates two thread ids. 184 */ 185 #pragma weak pthread_equal = _pthread_equal 186 int 187 _pthread_equal(pthread_t t1, pthread_t t2) 188 { 189 return (t1 == t2); 190 } 191 192 /* 193 * pthread_getschedparam: get the thread's sched parameters. 194 */ 195 #pragma weak pthread_getschedparam = _pthread_getschedparam 196 int 197 _pthread_getschedparam(pthread_t tid, int *policy, struct sched_param *param) 198 { 199 ulwp_t *ulwp; 200 id_t cid; 201 int error = 0; 202 203 if ((ulwp = find_lwp(tid)) == NULL) { 204 error = ESRCH; 205 } else { 206 cid = getparam(P_LWPID, ulwp->ul_lwpid, policy, param); 207 if (cid == -1) { 208 error = errno; 209 } else if (*policy == ulwp->ul_policy && cid == ulwp->ul_cid && 210 (*policy == SCHED_FIFO || *policy == SCHED_RR)) { 211 /* 212 * Return the defined priority, not the effective 213 * priority from priority ceiling mutexes. 214 */ 215 param->sched_priority = ulwp->ul_pri; 216 } else { 217 ulwp->ul_cid = cid; 218 ulwp->ul_pri = param->sched_priority; 219 _membar_producer(); 220 ulwp->ul_policy = *policy; 221 } 222 ulwp_unlock(ulwp, curthread->ul_uberdata); 223 } 224 225 return (error); 226 } 227 228 #pragma weak thr_getprio = _thr_getprio 229 int 230 _thr_getprio(thread_t tid, int *priority) 231 { 232 struct sched_param param; 233 int policy; 234 int error; 235 236 if ((error = _pthread_getschedparam(tid, &policy, ¶m)) == 0) 237 *priority = param.sched_priority; 238 return (error); 239 } 240 241 /* 242 * pthread_setschedparam: sets the sched parameters for a thread. 243 */ 244 #pragma weak pthread_setschedparam = _pthread_setschedparam 245 int 246 _pthread_setschedparam(pthread_t tid, 247 int policy, const struct sched_param *param) 248 { 249 return (_thr_setparam(tid, policy, param->sched_priority)); 250 } 251 252 #pragma weak thr_setprio = _thr_setprio 253 #pragma weak pthread_setschedprio = _thr_setprio 254 #pragma weak _pthread_setschedprio = _thr_setprio 255 int 256 _thr_setprio(thread_t tid, int prio) 257 { 258 struct sched_param param; 259 int policy; 260 int error; 261 262 /* 263 * _pthread_getschedparam() has the side-effect of setting 264 * the target thread's ul_policy, ul_pri and ul_cid correctly. 265 */ 266 if ((error = _pthread_getschedparam(tid, &policy, ¶m)) != 0) 267 return (error); 268 if (param.sched_priority == prio) /* no change */ 269 return (0); 270 return (_thr_setparam(tid, policy, prio)); 271 } 272