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aix.c (7199B)


      1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
      2 /* This Source Code Form is subject to the terms of the Mozilla Public
      3 * License, v. 2.0. If a copy of the MPL was not distributed with this
      4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      5 
      6 #include "primpl.h"
      7 
      8 #ifdef AIX_HAVE_ATOMIC_OP_H
      9 #  include <sys/atomic_op.h>
     10 
     11 PRInt32 _AIX_AtomicSet(PRInt32* val, PRInt32 newval) {
     12  PRIntn oldval;
     13  boolean_t stored;
     14  oldval = fetch_and_add((atomic_p)val, 0);
     15  do {
     16    stored = compare_and_swap((atomic_p)val, &oldval, newval);
     17  } while (!stored);
     18  return oldval;
     19 } /* _AIX_AtomicSet */
     20 #endif /* AIX_HAVE_ATOMIC_OP_H */
     21 
     22 #if defined(AIX_TIMERS)
     23 
     24 #  include <sys/time.h>
     25 
     26 static PRUint32 _aix_baseline_epoch;
     27 
     28 static void _MD_AixIntervalInit(void) {
     29  timebasestruct_t real_time;
     30  read_real_time(&real_time, TIMEBASE_SZ);
     31  (void)time_base_to_time(&real_time, TIMEBASE_SZ);
     32  _aix_baseline_epoch = real_time.tb_high;
     33 } /* _MD_AixIntervalInit */
     34 
     35 PRIntervalTime _MD_AixGetInterval(void) {
     36  PRIntn rv;
     37  PRUint64 temp;
     38  timebasestruct_t real_time;
     39  read_real_time(&real_time, TIMEBASE_SZ);
     40  (void)time_base_to_time(&real_time, TIMEBASE_SZ);
     41  /* tb_high is in seconds, tb_low in 10(-9)seconds */
     42  temp = 1000000000ULL * (PRUint64)(real_time.tb_high - _aix_baseline_epoch);
     43  temp += (PRUint64)real_time.tb_low; /* everything's 10(-9) seconds */
     44  temp >>= 16;                        /* now it's something way different */
     45  return (PRIntervalTime)temp;
     46 } /* _MD_AixGetInterval */
     47 
     48 PRIntervalTime _MD_AixIntervalPerSec(void) {
     49  return 1000000000ULL >> 16; /* that's 15258, I think */
     50 } /* _MD_AixIntervalPerSec */
     51 
     52 #endif /* defined(AIX_TIMERS) */
     53 
     54 #if !defined(PTHREADS_USER)
     55 
     56 #  if defined(_PR_PTHREADS)
     57 
     58 /*
     59 * AIX 4.3 has sched_yield().  AIX 4.2 has pthread_yield().
     60 * So we look up the appropriate function pointer at run time.
     61 */
     62 
     63 #    include <dlfcn.h>
     64 
     65 int (*_PT_aix_yield_fcn)() = NULL;
     66 int _pr_aix_send_file_use_disabled = 0;
     67 
     68 void _MD_EarlyInit(void) {
     69  void* main_app_handle;
     70  char* evp;
     71 
     72  main_app_handle = dlopen(NULL, RTLD_NOW);
     73  PR_ASSERT(NULL != main_app_handle);
     74 
     75  _PT_aix_yield_fcn = (int (*)())dlsym(main_app_handle, "sched_yield");
     76  if (!_PT_aix_yield_fcn) {
     77    _PT_aix_yield_fcn = (int (*)())dlsym(main_app_handle, "pthread_yield");
     78    PR_ASSERT(NULL != _PT_aix_yield_fcn);
     79  }
     80  dlclose(main_app_handle);
     81 
     82  if (evp = getenv("NSPR_AIX_SEND_FILE_USE_DISABLED")) {
     83    if (1 == atoi(evp)) {
     84      _pr_aix_send_file_use_disabled = 1;
     85    }
     86  }
     87 
     88 #    if defined(AIX_TIMERS)
     89  _MD_AixIntervalInit();
     90 #    endif
     91 }
     92 
     93 #  else /* _PR_PTHREADS */
     94 
     95 void _MD_EarlyInit(void) {
     96 #    if defined(AIX_TIMERS)
     97  _MD_AixIntervalInit();
     98 #    endif
     99 }
    100 
    101 #  endif /* _PR_PTHREADS */
    102 
    103 PRWord* _MD_HomeGCRegisters(PRThread* t, int isCurrent, int* np) {
    104 #  ifndef _PR_PTHREADS
    105  if (isCurrent) {
    106    (void)setjmp(CONTEXT(t));
    107  }
    108  *np = sizeof(CONTEXT(t)) / sizeof(PRWord);
    109  return (PRWord*)CONTEXT(t);
    110 #  else
    111  *np = 0;
    112  return NULL;
    113 #  endif
    114 }
    115 
    116 #  ifndef _PR_PTHREADS
    117 PR_IMPLEMENT(void)
    118 _MD_SET_PRIORITY(_MDThread* thread, PRUintn newPri) { return; }
    119 
    120 PR_IMPLEMENT(PRStatus)
    121 _MD_InitializeThread(PRThread* thread) { return PR_SUCCESS; }
    122 
    123 PR_IMPLEMENT(PRStatus)
    124 _MD_WAIT(PRThread* thread, PRIntervalTime ticks) {
    125  PR_ASSERT(!(thread->flags & _PR_GLOBAL_SCOPE));
    126  _PR_MD_SWITCH_CONTEXT(thread);
    127  return PR_SUCCESS;
    128 }
    129 
    130 PR_IMPLEMENT(PRStatus)
    131 _MD_WAKEUP_WAITER(PRThread* thread) {
    132  if (thread) {
    133    PR_ASSERT(!(thread->flags & _PR_GLOBAL_SCOPE));
    134  }
    135  return PR_SUCCESS;
    136 }
    137 
    138 /* These functions should not be called for AIX */
    139 PR_IMPLEMENT(void)
    140 _MD_YIELD(void) { PR_NOT_REACHED("_MD_YIELD should not be called for AIX."); }
    141 
    142 PR_IMPLEMENT(PRStatus)
    143 _MD_CREATE_THREAD(PRThread* thread, void (*start)(void*),
    144                  PRThreadPriority priority, PRThreadScope scope,
    145                  PRThreadState state, PRUint32 stackSize) {
    146  PR_NOT_REACHED("_MD_CREATE_THREAD should not be called for AIX.");
    147 }
    148 #  endif /* _PR_PTHREADS */
    149 #endif   /* PTHREADS_USER */
    150 
    151 /*
    152 * NSPR 2.0 overrides the system select() and poll() functions.
    153 * On AIX 4.2, we use dlopen("/unix", RTLD_NOW) and dlsym() to get
    154 * at the original system select() and poll() functions.
    155 */
    156 
    157 #if !defined(AIX_RENAME_SELECT)
    158 
    159 #  include <sys/select.h>
    160 #  include <sys/poll.h>
    161 #  include <dlfcn.h>
    162 
    163 static int (*aix_select_fcn)() = NULL;
    164 static int (*aix_poll_fcn)() = NULL;
    165 
    166 int _MD_SELECT(int width, fd_set* r, fd_set* w, fd_set* e, struct timeval* t) {
    167  int rv;
    168 
    169  if (!aix_select_fcn) {
    170    void* aix_handle;
    171 
    172    aix_handle = dlopen("/unix", RTLD_NOW);
    173    if (!aix_handle) {
    174      PR_SetError(PR_UNKNOWN_ERROR, 0);
    175      return -1;
    176    }
    177    aix_select_fcn = (int (*)())dlsym(aix_handle, "select");
    178    dlclose(aix_handle);
    179    if (!aix_select_fcn) {
    180      PR_SetError(PR_UNKNOWN_ERROR, 0);
    181      return -1;
    182    }
    183  }
    184  rv = (*aix_select_fcn)(width, r, w, e, t);
    185  return rv;
    186 }
    187 
    188 int _MD_POLL(void* listptr, unsigned long nfds, long timeout) {
    189  int rv;
    190 
    191  if (!aix_poll_fcn) {
    192    void* aix_handle;
    193 
    194    aix_handle = dlopen("/unix", RTLD_NOW);
    195    if (!aix_handle) {
    196      PR_SetError(PR_UNKNOWN_ERROR, 0);
    197      return -1;
    198    }
    199    aix_poll_fcn = (int (*)())dlsym(aix_handle, "poll");
    200    dlclose(aix_handle);
    201    if (!aix_poll_fcn) {
    202      PR_SetError(PR_UNKNOWN_ERROR, 0);
    203      return -1;
    204    }
    205  }
    206  rv = (*aix_poll_fcn)(listptr, nfds, timeout);
    207  return rv;
    208 }
    209 
    210 #else
    211 
    212 /*
    213 * In AIX versions prior to 4.2, we use the two-step rename/link trick.
    214 * The binary must contain at least one "poll" symbol for linker's rename
    215 * to work.  So we must have this dummy function that references poll().
    216 */
    217 #  include <sys/poll.h>
    218 void _pr_aix_dummy() { poll(0, 0, 0); }
    219 
    220 #endif /* !defined(AIX_RENAME_SELECT) */
    221 
    222 #ifdef _PR_HAVE_ATOMIC_CAS
    223 
    224 #  include "pratom.h"
    225 
    226 #  define _PR_AIX_ATOMIC_LOCK -1
    227 
    228 PR_IMPLEMENT(void)
    229 PR_StackPush(PRStack* stack, PRStackElem* stack_elem) {
    230  PRStackElem* addr;
    231  boolean_t locked = TRUE;
    232 
    233  /* Is it safe to cast a pointer to an int? */
    234  PR_ASSERT(sizeof(int) == sizeof(PRStackElem*));
    235  do {
    236    while ((addr = stack->prstk_head.prstk_elem_next) ==
    237           (PRStackElem*)_PR_AIX_ATOMIC_LOCK);
    238    locked = _check_lock((atomic_p)&stack->prstk_head.prstk_elem_next,
    239                         (int)addr, _PR_AIX_ATOMIC_LOCK);
    240  } while (locked == TRUE);
    241  stack_elem->prstk_elem_next = addr;
    242  _clear_lock((atomic_p)&stack->prstk_head.prstk_elem_next, (int)stack_elem);
    243  return;
    244 }
    245 
    246 PR_IMPLEMENT(PRStackElem*)
    247 PR_StackPop(PRStack* stack) {
    248  PRStackElem* element;
    249  boolean_t locked = TRUE;
    250 
    251  /* Is it safe to cast a pointer to an int? */
    252  PR_ASSERT(sizeof(int) == sizeof(PRStackElem*));
    253  do {
    254    while ((element = stack->prstk_head.prstk_elem_next) ==
    255           (PRStackElem*)_PR_AIX_ATOMIC_LOCK);
    256    locked = _check_lock((atomic_p)&stack->prstk_head.prstk_elem_next,
    257                         (int)element, _PR_AIX_ATOMIC_LOCK);
    258  } while (locked == TRUE);
    259 
    260  if (element == NULL) {
    261    _clear_lock((atomic_p)&stack->prstk_head.prstk_elem_next, NULL);
    262  } else {
    263    _clear_lock((atomic_p)&stack->prstk_head.prstk_elem_next,
    264                (int)element->prstk_elem_next);
    265  }
    266  return element;
    267 }
    268 
    269 #endif /* _PR_HAVE_ATOMIC_CAS */