1  /* Change priority ceiling setting in pthread_mutexattr_t.
       2     Copyright (C) 2006-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       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, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <errno.h>
      20  #include <pthreadP.h>
      21  #include <atomic.h>
      22  #include <shlib-compat.h>
      23  
      24  int
      25  __pthread_mutexattr_setprioceiling (pthread_mutexattr_t *attr, int prioceiling)
      26  {
      27    /* See __init_sched_fifo_prio.  */
      28    if (atomic_load_relaxed (&__sched_fifo_min_prio) == -1
      29        || atomic_load_relaxed (&__sched_fifo_max_prio) == -1)
      30      __init_sched_fifo_prio ();
      31  
      32    if (__glibc_unlikely (prioceiling
      33  			< atomic_load_relaxed (&__sched_fifo_min_prio))
      34        || __glibc_unlikely (prioceiling
      35  			   > atomic_load_relaxed (&__sched_fifo_max_prio))
      36        || __glibc_unlikely ((prioceiling
      37  			    & (PTHREAD_MUTEXATTR_PRIO_CEILING_MASK
      38  			       >> PTHREAD_MUTEXATTR_PRIO_CEILING_SHIFT))
      39  			   != prioceiling))
      40      return EINVAL;
      41  
      42    struct pthread_mutexattr *iattr = (struct pthread_mutexattr *) attr;
      43  
      44    iattr->mutexkind = ((iattr->mutexkind & ~PTHREAD_MUTEXATTR_PRIO_CEILING_MASK)
      45  		      | (prioceiling << PTHREAD_MUTEXATTR_PRIO_CEILING_SHIFT));
      46  
      47    return 0;
      48  }
      49  versioned_symbol (libc, __pthread_mutexattr_setprioceiling,
      50  		  pthread_mutexattr_setprioceiling, GLIBC_2_34);
      51  
      52  #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_4, GLIBC_2_34)
      53  compat_symbol (libpthread, __pthread_mutexattr_setprioceiling,
      54                 pthread_mutexattr_setprioceiling, GLIBC_2_4);
      55  #endif