linuxthreads/attr.c

   1 /* Linuxthreads - a simple clone()-based implementation of Posix        */
   2 /* threads for Linux.                                                   */
   3 /* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr)              */
   4 /*                                                                      */
   5 /* This program is free software; you can redistribute it and/or        */
   6 /* modify it under the terms of the GNU Library General Public License  */
   7 /* as published by the Free Software Foundation; either version 2       */
   8 /* of the License, or (at your option) any later version.               */
   9 /*                                                                      */
  10 /* This program is distributed in the hope that it will be useful,      */
  11 /* but WITHOUT ANY WARRANTY; without even the implied warranty of       */
  12 /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        */
  13 /* GNU Library General Public License for more details.                 */
  14
  15 /* Handling of thread attributes */
  16
  17 #include <errno.h>
  18 #include <string.h>
  19 #include <unistd.h>
  20 #include <sys/param.h>
  21 #include "pthread.h"
  22 #include "internals.h"
  23
  24 int __pthread_attr_init_2_1(pthread_attr_t *attr)
  25 {
  26   size_t ps = __getpagesize ();
  27
  28   attr->detachstate = PTHREAD_CREATE_JOINABLE;
  29   attr->schedpolicy = SCHED_OTHER;
  30   attr->schedparam.sched_priority = 0;
  31   attr->inheritsched = PTHREAD_EXPLICIT_SCHED;
  32   attr->scope = PTHREAD_SCOPE_SYSTEM;
  33   attr->guardsize = ps;
  34   attr->stackaddr = NULL;
  35   attr->stackaddr_set = 0;
  36   attr->stacksize = STACK_SIZE - ps;
  37   return 0;
  38 }
  39 #if defined HAVE_ELF && defined PIC && defined DO_VERSIONING
  40 default_symbol_version (__pthread_attr_init_2_1, pthread_attr_init, GLIBC_2.1);
  41
  42 int __pthread_attr_init_2_0(pthread_attr_t *attr)
  43 {
  44   attr->detachstate = PTHREAD_CREATE_JOINABLE;
  45   attr->schedpolicy = SCHED_OTHER;
  46   attr->schedparam.sched_priority = 0;
  47   attr->inheritsched = PTHREAD_EXPLICIT_SCHED;
  48   attr->scope = PTHREAD_SCOPE_SYSTEM;
  49   return 0;
  50 }
  51 symbol_version (__pthread_attr_init_2_0, pthread_attr_init, GLIBC_2.0);
  52 #else
  53 strong_alias (__pthread_attr_init_2_1, pthread_attr_init)
  54 #endif
  55
  56 int pthread_attr_destroy(pthread_attr_t *attr)
  57 {
  58   return 0;
  59 }
  60
  61 int pthread_attr_setdetachstate(pthread_attr_t *attr, int detachstate)
  62 {
  63   if (detachstate < PTHREAD_CREATE_JOINABLE ||
  64       detachstate > PTHREAD_CREATE_DETACHED)
  65     return EINVAL;
  66   attr->detachstate = detachstate;
  67   return 0;
  68 }
  69
  70 int pthread_attr_getdetachstate(const pthread_attr_t *attr, int *detachstate)
  71 {
  72   *detachstate = attr->detachstate;
  73   return 0;
  74 }
  75
  76 int pthread_attr_setschedparam(pthread_attr_t *attr,
  77                                const struct sched_param *param)
  78 {
  79   int max_prio = __sched_get_priority_max(attr->schedpolicy);
  80   int min_prio = __sched_get_priority_min(attr->schedpolicy);
  81
  82   if (param->sched_priority < min_prio || param->sched_priority > max_prio)
  83     return EINVAL;
  84   memcpy (&attr->schedparam, param, sizeof (struct sched_param));
  85   return 0;
  86 }
  87
  88 int pthread_attr_getschedparam(const pthread_attr_t *attr,
  89                                struct sched_param *param)
  90 {
  91   memcpy (param, &attr->schedparam, sizeof (struct sched_param));
  92   return 0;
  93 }
  94
  95 int pthread_attr_setschedpolicy(pthread_attr_t *attr, int policy)
  96 {
  97   if (policy != SCHED_OTHER && policy != SCHED_FIFO && policy != SCHED_RR)
  98     return EINVAL;
  99   if (policy != SCHED_OTHER && geteuid() != 0)
 100     return ENOTSUP;
 101   attr->schedpolicy = policy;
 102   return 0;
 103 }
 104
 105 int pthread_attr_getschedpolicy(const pthread_attr_t *attr, int *policy)
 106 {
 107   *policy = attr->schedpolicy;
 108   return 0;
 109 }
 110
 111 int pthread_attr_setinheritsched(pthread_attr_t *attr, int inherit)
 112 {
 113   if (inherit != PTHREAD_INHERIT_SCHED && inherit != PTHREAD_EXPLICIT_SCHED)
 114     return EINVAL;
 115   attr->inheritsched = inherit;
 116   return 0;
 117 }
 118
 119 int pthread_attr_getinheritsched(const pthread_attr_t *attr, int *inherit)
 120 {
 121   *inherit = attr->inheritsched;
 122   return 0;
 123 }
 124
 125 int pthread_attr_setscope(pthread_attr_t *attr, int scope)
 126 {
 127   switch (scope) {
 128   case PTHREAD_SCOPE_SYSTEM:
 129     attr->scope = scope;
 130     return 0;
 131   case PTHREAD_SCOPE_PROCESS:
 132     return ENOTSUP;
 133   default:
 134     return EINVAL;
 135   }
 136 }
 137
 138 int pthread_attr_getscope(const pthread_attr_t *attr, int *scope)
 139 {
 140   *scope = attr->scope;
 141   return 0;
 142 }
 143
 144 int __pthread_attr_setguardsize(pthread_attr_t *attr, size_t guardsize)
 145 {
 146   size_t ps = __getpagesize ();
 147
 148   /* First round up the guard size.  */
 149   guardsize = roundup (guardsize, ps);
 150
 151   /* The current implementation of LinuxThreads allocates 2MB stack space
 152      for each thread.  So the maximum guardsize is 2MB - pagesize.  */
 153   if (guardsize >= STACK_SIZE - ps)
 154     return EINVAL;
 155
 156   attr->guardsize = guardsize;
 157
 158   return 0;
 159 }
 160 weak_alias (__pthread_attr_setguardsize, pthread_attr_setguardsize)
 161
 162 int __pthread_attr_getguardsize(const pthread_attr_t *attr, size_t *guardsize)
 163 {
 164   *guardsize = attr->guardsize;
 165   return 0;
 166 }
 167 weak_alias (__pthread_attr_getguardsize, pthread_attr_getguardsize)
 168
 169 int __pthread_attr_setstackaddr(pthread_attr_t *attr, void *stackaddr)
 170 {
 171   attr->stackaddr = stackaddr;
 172   attr->stackaddr_set = 1;
 173   return 0;
 174 }
 175 weak_alias (__pthread_attr_setstackaddr, pthread_attr_setstackaddr)
 176
 177 int __pthread_attr_getstackaddr(const pthread_attr_t *attr, void **stackaddr)
 178 {
 179   /* XXX This function has a stupid definition.  The standard specifies
 180      no error value but what is if no stack address was set?  We simply
 181      return the value we have in the member.  */
 182   *stackaddr = attr->stackaddr;
 183   return 0;
 184 }
 185 weak_alias (__pthread_attr_getstackaddr, pthread_attr_getstackaddr)
 186
 187 int __pthread_attr_setstacksize(pthread_attr_t *attr, size_t stacksize)
 188 {
 189   /* We don't accept value smaller than PTHREAD_STACK_MIN.  */
 190   if (stacksize < PTHREAD_STACK_MIN)
 191     return EINVAL;
 192
 193   attr->stacksize = stacksize;
 194   return 0;
 195 }
 196 weak_alias (__pthread_attr_setstacksize, pthread_attr_setstacksize)
 197
 198 int __pthread_attr_getstacksize(const pthread_attr_t *attr, size_t *stacksize)
 199 {
 200   *stacksize = attr->stacksize;
 201   return 0;
 202 }
 203 weak_alias (__pthread_attr_getstacksize, pthread_attr_getstacksize)