1: /* Copyright (C) 2003, 2004, 2006, 2007 Free Software Foundation, Inc.
    2:    This file is part of the GNU C Library.
    3:    Contributed by Martin Schwidefsky <schwidefsky@de.ibm.com>, 2003.
    4: 
    5:    The GNU C Library is free software; you can redistribute it and/or
    6:    modify it under the terms of the GNU Lesser General Public
    7:    License as published by the Free Software Foundation; either
    8:    version 2.1 of the License, or (at your option) any later version.
    9: 
   10:    The GNU C Library 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 GNU
   13:    Lesser General Public License for more details.
   14: 
   15:    You should have received a copy of the GNU Lesser General Public
   16:    License along with the GNU C Library; if not, write to the Free
   17:    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   18:    02111-1307 USA.  */
   19: 
   20: #include <endian.h>
   21: #include <errno.h>
   22: #include <sysdep.h>
   23: #include <lowlevellock.h>
   24: #include <pthread.h>
   25: #include <pthreadP.h>
   26: 
   27: #include <shlib-compat.h>
   28: #include <kernel-features.h>
   29: 
   30: 
   31: int
   32: __pthread_cond_broadcast (cond)
   33:      pthread_cond_t *cond;
   34: {
   35:   int pshared = (cond->__data.__mutex == (void *) ~0l)
   36:                 ? LLL_SHARED : LLL_PRIVATE;
   37:   /* Make sure we are alone.  */
   38:   lll_lock (cond->__data.__lock, pshared);
   39: 
   40:   /* Are there any waiters to be woken?  */
   41:   if (cond->__data.__total_seq > cond->__data.__wakeup_seq)
   42:     {
   43:       /* Yes.  Mark them all as woken.  */
   44:       cond->__data.__wakeup_seq = cond->__data.__total_seq;
   45:       cond->__data.__woken_seq = cond->__data.__total_seq;
   46:       cond->__data.__futex = (unsigned int) cond->__data.__total_seq * 2;
   47:       int futex_val = cond->__data.__futex;
   48:       /* Signal that a broadcast happened.  */
   49:       ++cond->__data.__broadcast_seq;
   50: 
   51:       /* We are done.  */
   52:       lll_unlock (cond->__data.__lock, pshared);
   53: 
   54:       /* Do not use requeue for pshared condvars.  */
   55:       if (cond->__data.__mutex == (void *) ~0l)
   56:         goto wake_all;
   57: 
   58:       /* Wake everybody.  */
   59:       pthread_mutex_t *mut = (pthread_mutex_t *) cond->__data.__mutex;
   60: 
   61:       /* XXX: Kernel so far doesn't support requeue to PI futex.  */
   62:       /* XXX: Kernel so far can only requeue to the same type of futex,
   63:          in this case private (we don't requeue for pshared condvars).  */
   64:       if (__builtin_expect (mut->__data.__kind
   65:                             & (PTHREAD_MUTEX_PRIO_INHERIT_NP
   66:                                | PTHREAD_MUTEX_PSHARED_BIT), 0))
   67:         goto wake_all;
   68: 
   69:       /* lll_futex_requeue returns 0 for success and non-zero
   70:          for errors.  */
   71:       if (__builtin_expect (lll_futex_requeue (&cond->__data.__futex, 1,
   72:                                                INT_MAX, &mut->__data.__lock,
   73:                                                futex_val, LLL_PRIVATE), 0))
   74:         {
   75:           /* The requeue functionality is not available.  */
   76:         wake_all:
   77:           lll_futex_wake (&cond->__data.__futex, INT_MAX, pshared);
   78:         }
   79: 
   80:       /* That's all.  */
   81:       return 0;
   82:     }
   83: 
   84:   /* We are done.  */
   85:   lll_unlock (cond->__data.__lock, pshared);
   86: 
   87:   return 0;
   88: }
   89: 
   90: versioned_symbol (libpthread, __pthread_cond_broadcast, pthread_cond_broadcast,
   91:                   GLIBC_2_3_2);